Aims Patients with type 2 diabetes mellitus (T2DM) are known to have impaired resting myocardial energetics and impaired myocardial perfusion reserve, even in the absence of obstructive epicardial coronary artery disease (CAD). Whether or not the pre-existing energetic deficit is exacerbated by exercise, and whether the impaired myocardial perfusion causes deoxygenation and further energetic derangement during exercise stress, is uncertain.Methods and results Thirty-one T2DM patients, on oral antidiabetic therapies with a mean HBA1c of 7.4 ± 1.3%, and 17 matched controls underwent adenosine stress cardiovascular magnetic resonance for assessment of perfusion [myocardial perfusion reserve index (MPRI)] and oxygenation [blood-oxygen level-dependent (BOLD) signal intensity change (SIΔ)]. Cardiac phosphorus-MR spectroscopy was performed at rest and during leg exercise. Significant CAD (>50% coronary stenosis) was excluded in all patients by coronary computed tomographic angiography. Resting phosphocreatine to ATP (PCr/ATP) was reduced by 17% in patients , compared with controls (2.07 ± 0.35); during exercise, there was a further 12% reduction in PCr/ATP (P = 0.005) in T2DM patients, but no change in controls. Myocardial perfusion and oxygenation were decreased in T2DM . Exercise PCr/ATP correlated with MPRI  and BOLD SIΔ , but there were no correlations between rest PCr/ATP and MPRI or BOLD SIΔ.Conclusion The pre-existing energetic deficit in diabetic cardiomyopathy is exacerbated by exercise; stress PCr/ATP correlates with impaired perfusion and oxygenation. Our findings suggest that, in diabetes, coronary microvascular dysfunction exacerbates derangement of cardiac energetics under conditions of increased workload. Myocardial energy depletion in patients with diabetes is a multifactorial phenomenon, related to limitations in uptake and utilization of substrates,6 mitochondrial dysfunction,7 and impaired energy transfer from mitochondria to myofibrils.8 These metabolic changes, in combination with impaired myocardial perfusion, may decrease the ability of the diabetic heart to adapt to acute increases in workload. Further derangement of the energetic deficit on increased workload could potentially limit myocardial contractile reserve and exacerbate diastolic dysfunction and stimulate maladaptive pathways, eventually leading to heart failure.10Diabetes mellitus (DM) is associated with increased risk of congestive heart failure31P-MRS) allows non-invasive assessment of the myocardial phosphocreatine to ATP concentration ratio (PCr/ATP), which is a sensitive indicator of the myocardial energy status.11 Using 31P-MRS, we, and others, have shown that the diabetic heart is energetically compromised, with a decreased PCr/ATP, at rest.4 However, changes in cardiac metabolic reserve and energy metabolism in diabetic patients under conditions of increased workload have not been studied.Phosphorus-magnetic resonance spectroscopy  CMR or oxygenation-sensitive CMR has the ability to non-invasively assess myocardial tissue oxygenation during vasodilator stress, providing a more direct measure of microvascular dysfunction and ischaemia than perfusion.16 Oxygenation-sensitive CMR can non-invasively assess myocardial tissue oxygenation without the need for exogenous contrast by measuring BOLD signal intensity (SI) differences, which reflect deoxygenated haemoglobin concentration during adenosine stress.17 Although the technique has some limitations for widespread clinical use,18 the potential benefits of BOLD imaging were demonstrated in multiple clinical studies.21 Thus, CMR allows a comprehensive investigation of the interplay between metabolic and ischaemic changes in the diabetic heart.Cardiovascular magnetic resonance (CMR) during the first pass of an injected tracer permits assessment of myocardial perfusion reserve during pharmacological stress.The primary objective of this study was to assess whether the pre-existing cardiac energetic deficit is exacerbated by exercise in patients with type 2 diabetes mellitus (T2DM) as a measure of metabolic reserve. The second objective was to assess myocardial perfusion reserve and oxygenation during vasodilator stress and to examine their relationship with myocardial energy status in T2DM patients, who were free of significant epicardial coronary artery stenosis. We hypothesized that the intrinsic metabolic deficit and coronary microvascular dysfunction in diabetes, either alone or in combination, will reduce the ability of the diabetic myocardium to adapt to acute increases in workload and exacerbate the energetic derangement.22The study complies with the Declaration of Helsinki and was approved by the National Research Ethics Committee (REC Ref. 13/SW/0257), and informed written consent was obtained from each participant. Thirty-nine subjects with T2DM on oral antidiabetic therapies and 17 volunteers of similar age and body mass index (BMI) were recruited. T2DM was diagnosed according to the World Health Organization criteria.31P-MRS , transthoracic echocardiography, and fasting blood tests.Subjects were excluded if they had a history of cardiovascular disease, chest pain, tobacco smoking, uncontrolled hypertension [resting systolic blood pressure (BP) >140 mmHg and diastolic BP >90 mmHg], contraindications to MR imaging (MRI), ischaemic changes on 12-lead ECG, or renal impairment (estimated glomerular filtration rate below 30 mL/min). T2DM participants were excluded if they were taking insulin. Additionally, patients were screened for obstructive epicardial CAD  by coronary computed tomographic angiography (CCTA). Subjects with no evidence of significant epicardial CAD on CCTA underwent CMR, 23 Participants received beta-blockade (intravenous metoprolol) and sublingual GTN to achieve a heart rate of <65 b.p.m. A preliminary unenhanced scan was performed to assess coronary artery calcium score. During the CCTA acquisition, 80 mL of iodinated contrast  was injected followed by a 50 mL saline flush. Significant coronary artery disease (CAD) was defined as >50% luminal stenosis.CCTA scans were performed on a 64-slice CT scanner  in accordance with guidelines from the Society of Cardiovascular Computed Tomography.24 Strain imaging was performed using myocardial tagging sequence, as described previously.25CMR was performed on a 3 T system . All participants refrained from caffeine ingestion for 24 h and were scanned after fasting overnight. Cine imaging was performed using standard methods.26 For oxygenation-sensitive CMR, three ventricular short-axis (SA) slices  were acquired at rest. Adenosine (140 µg/kg/min) was then infused for at least 3 min, and the same three BOLD images were acquired during stress. Subsequently (4–5 min after commencing adenosine), a 0.03 mmol/kg bolus of gadolinium-based contrast  was injected, followed by 15 mL of normal saline at a rate of 6 mL/s for first-pass perfusion imaging. Adenosine was then discontinued and, after at least 20 min, another 0.03 mmol/kg bolus of gadolinium was given for post-adenosine rest perfusion imaging. Heart rates and BPs were recorded at baseline and at 1 min intervals during stress.Oxygenation-sensitive CMR and stress perfusion CMR were performed as described previously.27For late gadolinium enhancement (LGE) CMR, a top-up bolus of 0.09 mmol/kg of Gadoterate meglumine was administered immediately after rest perfusion imaging . LGE images were acquired as described previously.©  by manually tracing the endocardial and epicardial contours in end-diastolic and end-systolic images, as described previously.24Left ventricular (LV) volumes, ejection fraction, and mass were calculated using cmr4228Post-processing analysis of tagging images was performed using CIM-Tag software . The peak systolic circumferential strain, global longitudinal strain, and diastolic strain rate data were analysed from the mid-short axis and horizontal long-axis tagging images, as described previously.29 Briefly, myocardial SI was measured after tracing endocardial and epicardial contours. Mean SIs were calculated for resting and stress conditions by averaging signal measurements from images during adenosine resting and stress, respectively, and were corrected for variations in heart rate, as described previously.29The oxygenation-sensitive analysis technique has been described previously.30 in a blinded fashion by two operators (E.L. and A.L.).For analysis of myocardial perfusion, SI over time curves was generated by tracing endocardial and epicardial contours (cmr42) after correction for displacement during breathing. A region of interest was drawn in the LV blood pool to obtain an arterial input function. Similar to oxygenation analysis, the myocardium was divided into equiangular segments on the basis of the American Heart Association segmentation model. Post-adenosine rest and stress myocardial perfusion upslopes were calculated using a five-point linear fit model of SI vs. time and normalized to the LV blood pool upslope. Myocardial perfusion reserve index (MPRI) was derived for each of the 16 segments, defined as the ratio of stress to rest normalized myocardial perfusion upslopeFor LGE analysis, areas of contrast enhancement were visually scored as absent or present by consensus of two experienced operators (E.L. and M.M.). LGE was considered present only if myocardial enhancement was confirmed on both SA and matching long-axis locations.31P-MRS was performed to obtain the rest and exercise PCr/ATP from a voxel placed in the mid-ventricular septum, with the subjects lying prone with their heart over the centre of the 31P heart/liver coil in the iso-centre of the magnet, as described previously.32 Acquisition time was 9 min during rest and 9 min during leg exercise lying prone, with 2.5 kg weights attached to both ankles.31P-MRS post-processing analysis was performed as previously described.34The rate pressure product (RPP) was calculated using the product of the heart rate and systolic BP, providing a measure of cardiac work. The starting RPP was calculated during the baseline spectral acquisition. Subjects then initiated exercise with repeated and alternate knee flexion, aiming to double the baseline RPP, with feedback given throughout. When maintained at a steady level of exercise, reached after 1 min, the exercise scans were acquired. Haemodynamic measurements were taken and recorded every minute and the mean exercise RPP calculated. Subjects maintained a steady exercise level during the 9 min acquisition of spectra. The volunteers stopped exercising on completion of the exercise spectrum. t-test. The χ2 test or Fisher's exact test was used to compare discrete data as appropriate. Bivariate correlations were performed using Pearson's or Spearman's method, as appropriate. Comparisons between rest and exercise energetics in patients and controls were performed with the two-tailed paired t-test. A P-value less than 0.05 was considered significant. All statistical analyses were performed with IBM SPSS Statistics version 20 .All data are expressed as mean ± standard deviations, apart from diabetes duration which is expressed as median, and were checked for normality using the Kolmogorov–Smirnov test. Comparisons between the two groups were performed by Student's A priori sample size calculation was performed to detect a 13% drop in the PCr/ATP ratio in the T2DM cohort during stress. Based on pilot data (PCr/ATP rest 1.91 ± 0.25 and stress 1.65 ± 0.28) assuming two-tailed paired t-test analysis (α = 0.05 and β = 0.8), calculations suggested that 11 T2DM participants would be needed. A second a priori sample size calculation was also performed to detect a 10% difference in the PCr/ATP ratio in T2DM when compared with normal. Assuming two-tailed independent t-test analysis (α = 0.05 and β = 0.8), pilot data  suggested that eight T2DM and eight normal subjects would be needed to detect an 18% difference in the PCr/ATP ratio at rest. These targets were achieved in our study.2) with T2DM, median diabetes duration 7 years [interquartile range (IQR): 1–8] and mean glycated haemoglobin level 7.4 ± 1.3%, and 17 controls  were studied.Of the 39 diabetic patients screened in the study, 8 were excluded . Thirty-one patients  was on statin therapy; hence, total and low-density lipoprotein (LDL) cholesterol levels were lower than those in controls.Demographic, clinical, biochemical, and echocardiographic data are shown in Table 2. There was no significant difference in LV ejection fraction between patients with T2DM and controls. Diabetes was associated with concentric LV remodelling , with reduced LV diastolic volumes (P < 0.001) and increased maximal wall thickness (P = 0.016). LV mass did not differ between the two groups. Mid-ventricular systolic circumferential strain and global longitudinal strain were impaired in patients with T2DM compared with controls, indicating subtle alteration of both circumferential and longitudinal LV contractile function, in line with a previous study.35CMR results for LV volumes and function are summarized in Table 3. Adenosine stress and exercise led to similar percentage increases in RPP.Rest, post-adenosine rest, physiological stress and pharmacological stress BP, and heart rate responses are summarized in P = 0.001), and there was a further 12% decrease in PCr/ATP with exercise . In contrast, there was no significant change in PCr/ATP in healthy controls with exercise. Figure 3 shows the representative rest and exercise 31P-MR spectra.Diabetes was associated with a 17% decrease in PCr/ATP at rest compared with controls . During vasodilator stress, patients with T2DM showed evidence of blunted oxygenation response [signal intensity change (SIΔ): T2DM 7.3 ± 7.8%], compared with controls . Figure 5 shows representative CMR images of oxygenation and perfusion.Mean MPRI in the T2DM group was 24% lower than that in controls . Impaired MPRI was associated with blunting of myocardial oxygenation during vasodilator stress . There was also a positive correlation between exercise PCr/ATP and oxygenation SIΔ , whereas there was no correlation between the rest PCr/ATP and oxygenation SIΔ. Systolic circumferential strain, which is a CMR marker that is known to represent LV contractile function, correlated with rest PCr/ATP  and exercise PCr/ATP .In line with a previous study,31P-MRS to study patients with T2DM free of significant obstructive epicardial CAD, we assessed the effects of diabetes on cardiac metabolic reserve and how metabolic reserve relates to both myocardial oxygenation and perfusion reserve. We demonstrated that during exercise, the pre-existing energetic deficit in patients with diabetes, as determined by PCr/ATP, is exacerbated. We confirm the previous finding of an impaired myocardial perfusion reserve in diabetes.36 We now also show that patients with diabetes not only have impaired perfusion, but also evidence of blunted myocardial oxygenation at stress. Finally, we demonstrate that although myocardial energy metabolism at rest does not correlate with coronary microvascular dysfunction and is primarily a result of an intrinsic metabolic deficit, during exercise microvascular dysfunction exacerbates the energetic deficit.Using CMR and 11 linked to contractile dysfunction,11 and is a well-recognized complication of diabetes.4 Here, we demonstrate exacerbation of this energetic deficit during exercise in stable patients with diabetes, indicating impaired cardiac metabolic reserve.Myocardial energetic compromise, indicated by decreased PCr/ATP, is a predictor of mortality,37 These mechanisms include increased contribution of carbohydrates to energy production glycogenolysis,38 increased glucose uptake and glycolysis,39 and increased rates of phosphotransferase reactions.40 The primary energy reserve compound in the heart is PCr, and the enzyme creatine kinase is thought to allow the transfer of the high-energy phosphate bond between ATP and PCr, through the phosphotransferase reactions, in order to diffuse energy from the mitochondria to the myofibrils as PCr.9 These changes require the metabolic machinery to be flexible when, in contrast, diabetes is associated with metabolic inflexibility. The further drop in PCr/ATP during exercise in our patients with diabetes can potentially be explained by metabolic inflexibility,41 insufficient oxygen delivery, in addition to an impaired oxidative metabolism in diabetes resulting in reduced ATP production.7The healthy myocardium has rapid response mechanisms to deal with acute changes in energy demand, providing a large metabolic reserve.The causal role of altered energetics in contractile dysfunction in diabetic hearts is controversial. In our study, we show a correlation between myocardial systolic strain and the rest and stress PCr/ATP, suggesting a link between the two; however, the causality of this relationship will need to be investigated in future studies.Given the fact that we have shown significant abnormalities in metabolic reserve, myocardial perfusion reserve, and myocardial oxygenation response to adenosine stress in a stable diabetes population, similar or amplified findings could potentially be expected in diabetic patients with more advanced cardiovascular disease. Future studies should confirm this.42 Coronary microvascular dysfunction in diabetes is a multifactorial phenomenon, related to changes in perivascular and interstitial fibrosis,43 reduced capillary density, and autonomic neuropathy.44 Myocardial hypoperfusion does not always reflect tissue ischaemia, as oxygen demand may vary in different pathophysiological states. Indeed, some degree of dissociation exists between flow and oxygenation in the setting of CAD and dilated cardiomyopathy.45Impaired myocardial perfusion, either due to coronary microvascular dysfunction or due to endothelial dysfunction in diabetes, results in a failure to increment myocardial blood flow during acute increases in cardiac workload.The interplay between myocardial perfusion and oxygenation in diabetes has previously not been explored. Our study shows that, in the context of well-controlled diabetes, myocardial perfusion reserve is impaired and oxygenation during vasodilator stress is blunted and that these changes correlate with each other. These findings support the concept that hypoperfusion as a result of microvascular dysfunction plays a role in the impaired ability to increase and/or maintain myocardial oxygenation during vasodilatory stress in diabetes.The endothelium has been recognized to be a major regulator of vascular tone and growth. Experimental and clinical studies have demonstrated the association between diabetes and endothelium-dependent relaxation impairment. Although in our study we assessed myocardial perfusion reserve to adenosine stress, this parameter is both endothelium- and non-endothelium-dependent, and an observational study such as ours cannot clearly identify the mechanisms responsible for the reduced coronary vasodilation response to adenosine.47 Subjecting our participants to a third stress protocol (in addition to leg exercise during the acquisition of 31P-MRS and adenosine stress for the assessment of MPRI and oxygenation SIΔ) was deemed too high a burden on study subjects as this would lead to significantly longer adenosine infusion times, higher risk of adverse event rates, and high drop-out rates. For the same reasons, we have not carried out invasive coronary angiography for the assessment of endothelium-dependent coronary vasodilatation and vascular smooth muscle cell responsiveness. Although the impaired myocardial perfusion reserve demonstrated is commonly attributed to microvascular disease, in the current study, we cannot mechanistically differentiate between endothelial dysfunction and impaired smooth muscle relaxation as potential causes for the observed changes in diabetes.This study is limited by a relatively small sample size, in line with its proof-of-principle nature, and further studies are needed to understand the complex interaction between metabolic reserve and other factors. The principal limitation of our study is the lack of repeated assessment of myocardial function during stress. However, previous studies have shown exaggerated diastolic and systolic dysfunction in response to stress in patients with diabetes.The leg flexion stress was submaximal during the 9 min of acute physical exercise, with an average RPP increase of 40–50% in patients and controls, likely representing the physical constraints of exercising in an MRI scanner. However, this moderate exercise reflects typical levels of exercise that patients with diabetes would perform in daily life. Although mean rest and exercise RPP were higher in diabetics, increases in RPP were similar in the two groups.CCTA was not performed in the normal volunteers to prevent unnecessary ionizing radiation exposure. Significant CAD was deemed to be unlikely in this normal cohort, and this is further supported by the fact that perfusion and oxygenation values were within the normal range.11 which have been linked to contractile dysfunction and are predictors of mortality.48 Moreover, these findings were detected in a subclinical setting of well-controlled and stable patients, and more profound alterations may be expected in overt diabetic cardiomyopathy.The current study provides important insights into the interplay of perfusion, oxygenation, and metabolic changes during stress in the diabetic heart. We have identified the presence of markers of poor prognosis such as myocardial energetic compromise and impaired perfusion reserve,49 may in the future become therapeutic targets for patients with diabetic cardiomyopathy.Our findings suggest that strategies aimed at improving metabolic reserve and myocardial oxygenation together, such as pharmacological activation of the hypoxia-inducible factor pathway, which increases angiogenesis and oxygen-carrying capacity and metabolically upregulates oxygen-independent ATP synthesis,Future proof-of-principle clinical studies may use stress myocardial PCr/ATP and the BOLD SIΔ to monitor the early energetic and vascular response of the heart to novel therapies, and it is possible that these methods may provide surrogate markers of long-term prognostic effects.The pre-existing energetic deficit in diabetic cardiomyopathy is further exacerbated during exercise. Although the myocardial PCr/ATP ratio at rest is not related to coronary microvascular dysfunction and is primarily a result of intrinsic metabolic dysfunction, during exercise, microvascular dysfunction appears to exacerbate the energetic deficit. Diabetes is associated with a reduction in perfusion reserve severe enough to lead to myocardial deoxygenation and further exacerbation of the energetic abnormalities during increased workload. These mechanisms may contribute to the pathophysiology of the cardiomyopathy process in diabetes.The study was supported by the Oxford Partnership Comprehensive Biomedical Research Centre with funding from the Department of Health's National Institute for Health Research Biomedical Research Centers. S.N. acknowledges support from the Oxford British Heart Foundation Center of Research Excellence. C.T.R. is supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (Grant no. 098436/Z/12/Z). Funding to pay the Open Access publication charges for this article was provided by Wellcome Trust (Grant Number 098436/Z/12/Z).Conflict of interest: none declared.


A 74-year-old man presented with chest pain and dyspnoea at the cardiology outpatient clinic. His past medical history included an anterior myocardial infarction in 2008. In the coronary angiogram, a ‘halo image’ was seen right after the injection of the contrast agent, and it corresponded with the location of the left ventricular aneurysm. A calcified left ventricular aneurysm with mural thrombus was confirmed with cardiac MRI and a CT scan. A 74-year-old man presented with chest pain and dyspnoea at the cardiology outpatient clinic. His past medical history included an anterior myocardial infarction in 2008.His ECG revealed normal sinus rhythm with poor R-wave progression in the precordial leads. A transthoracic echocardiogram demonstrated a left ventricular aneurysm with a mural thrombus and ejection fraction of 25%. The chest X-ray showed a peculiar oval calcified image related to a left ventricle aneurysm . A nucleLeft ventriculography was not performed because of the possibility of elevated left ventricular end-diastolic pressure, which might have caused the development of acute pulmonary oedema. A calcified left ventricular aneurysm with a mural thrombus was confirmed with cardiac MRI and a CT scan , 4. The Left ventricular aneurysm (LVA) is a serious complication after acute myocardial infarction, and can lead to heart failure. Despite recent progress in revascularisation techniques, a large transmural myocardial infarction often results in the formation of a dyskinetic or akinetic LVA. This is followed by an enlarged ventricular cavity and abnormal ventricular shape that permits maximal conversion of tension generated by the myocardium into cavity pressure, and then congestive heart failure, arrhythmia and thrombogenesis.1Curvilinear calcification at the left ventricular apex strongly suggested the presence of an aneurysm. The distribution of this calcification coincided with the typical location of left ventricular aneurysms, which are usually located at the apex and often involve the anterior and lateral walls. Trauma, cardioversion, infection and endocardial fibrosis are rare causes of coarse, amorphous myocardial calcifications, which are distinct from the fine, curvilinear calcifications of a left ventricular aneurysm.2Similar previous case reports also demonstrated a calcified LVA using left ventriculography, chest X-ray, cardiac magnetic resonance imaging and computerised tomography.


Since a male-related higher cardiovascular morbidity and mortality in patients with Chagas’ heart disease has been reported, we aimed to investigate gender differences in myocardial damage assessed by cardiovascular magnetic resonance (CMR).r = 0.64, female r = 0.73, both P < 0.001), with males showing significantly greater myocardial fibrosis (P = 0.002) and lower LV ejection fraction (P < 0.001) than females. After adjustment for potential confounders, gender remained associated with myocardial dysfunction, and 53% of the effect was mediated by myocardial fibrosis (P for mediation = 0.004). Also, the transmural pattern was more prevalent among male patients  as well as the myocardial heterogeneity or gray zone .Retrospectively, 62 seropositive Chagas’ heart disease patients referred to CMR (1.5 T) and with low probability of having significant coronary artery disease were included in this analysis. Amongst both sexes, there was a strong negative correlation between LV ejection fraction and myocardial fibrosis (male We observed gender-related differences in myocardial damage assessed by CMR in patients with Chagas’ heart disease. As myocardial fibrosis and myocardial dysfunction are associated to cardiovascular outcomes, our findings might help to understand the poorer prognosis observed in males in Chagas’ disease. Trypanosoma cruzi (T. cruzi) and has recently become a global health concern [Considered a neglected tropical disease, Chagas’ disease is caused by a protozoan parasite,  concern , due to  concern , 3. In L concern .Patients with Chagas’ heart disease have a poorer prognosis in comparison to other cardiomyopathies and, in particular, male gender has been associated to a higher mortality rates . The reaCardiovascular magnetic resonance (CMR) is able to assess the extent of the myocardial fibrosis (MF), which correlates to LV ejection fraction (LVEF) and is a marker of disease severity in Chagas’ heart disease , 7. We sFrom 2 previous studies , 8, 62 aCMR was performed with a 1.5 T GE CV/i CMR System (Wakeusha Wisconsin). Ventricular function, volumes and mass were obtained from at least 10 short-axis ventricular slices, imaged with a steady state free precession pulse sequence, covering the entire left ventricle. Late gadolinium enhancement (LGE) images were acquired 10–20min after an intravenous bolus of 0.2 mmol/kg of gadolinium-based contrast, with an inversion-prepared gradient echo-sequence. The sequence parameters for cine/LGE imaging were, respectively: repetition time 3.9/7.1 ms, echo time 1.7/3.1 ms, flip angle 45°/20°, cardiac phases 20/1, views per segment 8/16 to 32, matrix 256 × 128/256 × 192, slice thickness 8/8 mm, gap between slices 2/2 mm and field of view 32 to 38/32 to 38 cm, inversion time none/150 to 250 ms, receiver bandwidth 125/31.25 kHz, number of excitations 1/1, acquisition every heart beat/every-other heart beat.All CMR images were analyzed with the CVI42 software  by a trained observer. End-systolic, end-diastolic LV volumes, LV mass and LV ejection fraction were measured by standard methods . For quaChi-squared or Fisher-exact tests and two-sample t-tests or Wilcoxon rank sum test for categorical or continuous data, respectively, were performed for comparing baseline characteristics across gender groups. The correlation between MF and LVEF was performed by Spearman’s test.We assumed that MF lies on the causal pathway between gender and myocardial dysfunction in Chagas’ disease, as a mediator variable and we tested the following mediation assumptions : gender P-value < 0.05 was considered as statistically significant and all reported P-values were two-tailed.All statistical analyses were performed with Stata 13.0  and a P = 0.55) as well as relative low prevalence of CAD risk factors. Although higher in males, both gender groups had low mean high-risk CAD score . Moreover, 35 of our patients (56%) had either an invasive or coronary computed tomographic (CT) angiography during their follow-up and none of them had obstructive CAD.Patient characteristics are shown in Table P = 0.04). Additionally, LV and RV remodeling was more pronounced in male than female patients, with males presenting significantly higher LV/RV dilation, LV mass and lower LV/RV ejection fraction than females.Heart failure symptoms were significantly more frequent and severe among male patients  (Table P = 0.004) and apical segments   (Table Most of patients had MF (77%) and MF was similarly frequent in male and female patients , non-ischemic patterns were frequently and concomitantly observed (mean > 3 types of LGE patterns). Only 30% patients had subendocardial and/or transmural patterns and did not undergo any angiography during follow-up. Interestingly, these potentially ischemic patterns were also found in 24.6% of LV segments (n = 138/560) of those patients who had angiography , subepicardial  and midwall patterns    and this relationship was comparably strong among males  and females , with no indication of an effect modification by gender   was negatively correlated with LVEF (P = 0.02) when MF was added as predictor in the model. In the mediation analysis . In a multivariate model to adjust for CAD risk factors, gender remained associated with myocardial dysfunction  and 30% lower mean LVEF (95% CI 18–43%) compared to female , as well as higher extent of the gray zones. Interestingly, the transmural pattern has been identified as independent predictor to ventricular tachycardia (4.1-fold greater) in Chagas’ heart disease [Furthermore, the presence, size and heterogeneity of MF assessed by CMR have been described as independent predictors for death in ischemic and non-ischemic cardiomyopathies –31. Besi disease . A highe disease .There are several limitations in this study. First, although ventricular remodeling and MF have been linked to worse clinical prognosis, this study was not designed to investigate cardiac outcomes. Secondly, as this was a cross-sectional study in Chagas’ disease, the time of disease onset remained undetermined, and duration of exposure could influence myocardial damage. However, children aged <5 years are most likely to be infected in domiciliary vector transmission  , 34, andOur study demonstrated for first time gender-specific differences in myocardial damage in Chagas’ heart disease by CMR. Male gender was associated with a higher amount of myocardial fibrosis and worse ventricular remodeling. The relationship of these findings with clinical outcomes in Chagas’ heart disease warrants further investigation.


We sought to determine whether information from a readily available standard 12-lead electrocardiogram (ECG) could be utilized to estimate infarct size, extent of transmural infarction, and extent of nonviable myocardium on CMR.Myocardial infarction (Qw), fragmented QRS (fQRS), and T wave inversion (TWI)]. Contiguous Qw (cQw MI) and TWI (cTWI) required involvement of two leads in a coronary distribution. Qw, fQRS, and TWI in individual leads were also examined. CMR infarct mass as a percentage total left ventricular (LV) mass (Infarct%) and LV ejection fraction (LVEF) were planimetered from late gadolinium enhanced (LGE) and cine short axis stacks, respectively. LGE images were also scored visually on a 17-segment model for the total number of segments with MI that were transmural at any point  and the total number of segments that were >50% infarcted (Nonviable Segments).Patients with a clinical history of MI enrolled in the DETERMINE and PREDETERMINE Trial and Registry  were included. Patients with left bundle branch block were excluded. ECG's were analyzed for candidate ECGs markers, which may signify the presence and extent of MI [Q waves Of the 550 patients  included in the analysis, 332(60%) had cQw MI, 216(39%) had fQRS, 235(43%) had cTWI, and 101(18%) had none of these ECG markers. Patients without any ECG markers had an infarct size of 9.0 ± 6.4% as compared to 14.0 ± 7.7%, 18.7 ± 9.2%, and 20.3 ± 9.7% for those with one (n = 179), two (n = 206), or all three (n= 64) ECG markers (p < 0.001). By multivariate linear regression, the presence of cQwMI, fQRS, and cTWI were independently associated with an increase in MI% by 6.3%, 2.4%, and 3.5%, (p≤0.001). On per lead analysis, multivariate linear regression demonstrated a significant continuous relationship between MI% and the number of leads affected by Qw, fQRS, and TWI. MI% was 7.8% when all leads were free of ECG markers and increased by 1.7%, 0.7%, and 0.8% for each lead affected by Qw, fQRS, and TWI (p≤0.001). The number of transmural segments and the number of nonviable segments was significantly higher in patients with cQW MI, fQRS, and cTWI than those without these ECG markers (see Figure Qw, fQRS, and TWI on ECG are independently associated with an increase in MI% measured by CMR in patients with a history of MI. Patients with these ECG markers also have a greater extent of transmural MI and nonviable myocardium, which increases with each additional marker seen on ECG. ECG estimates of MI size and extent may be useful to guide further risk stratification for sudden cardiac death.


The current method for a non-invasive assessment of diastolic dysfunction is complex with the use of algorithms of many different echocardiographic parameters. Total average diastolic longitudinal displacement (LD), determined by colour tissue Doppler imaging (TDI) via the measurement of LD during early diastole and atrial contraction, can potentially be used as a simple and reliable alternative.n = 45), LV hypertrophy (n = 49), left ventricular (LV) dilation (n = 30), and mitral regurgitation (n = 33). Intra and interobserver variability of diastolic LD measures was tested in 125 patients.In 206 patients, using GE Healthcare Vivid E7 and 9 and Echopac BT11 software, we determined both diastolic LD, measured in the septal and lateral walls in the apical 4-chamber view by TDI, and the degree of diastolic dysfunction, based on current guidelines. Of these 206 patients, 157 had cardiac anomalies that could potentially affect diastolic LD such as severe systolic heart failure . Patients with LV hypertrophy had preserved total average diastolic LD despite being classified as having diastolic dysfunction. Reproducibility of LD measures was acceptable.A linear relationship between total average diastolic LD and the degree of diastolic dysfunction was found. A total average diastolic LD of 10 mm was found to be a consistent threshold for the general discrimination of patients with or without diastolic dysfunction. Using linear regression, total average diastolic LD was estimated to fall by 2.4 mm for every increase in graded severity of diastolic dysfunction  contains supplementary material, which is available to authorized users. There is no simple means of reliably diagnosing left ventricular (LV) diastolic dysfunction: The current method for a non-invasive assessment of diastolic function requires the use of algorithms primarily based on a pulsed Doppler measurement of early mitral inflow velocity (E) and a colour tissue Doppler imaging (TDI) assessment of early mitral annular velocity (e’), thereby giving an indirect assessment of LV filling pressures (E/e’), as determined by the Bernouili principle and Laplace law . Other pEven though it is agreed that no single current echocardiographic measure is sufficient for a diagnosis of LV diastolic dysfunction, the use of algorithms of many different echocardiographic parameters is also problematic as a situation of “one size fits all” arises. Additionally, the fundamental use of velocity based parameters in these algorithms is deficient as the use of velocities as a determinant of diastolic function only takes one snapshot of imaging into consideration, thereby making an accurate depiction of severity difficult to obtain, especially in patients with atrial fibrillation. Lastly, the echocardiographic parameters used in these algorithms are only estimates of LV filling pressures and are subject to limitations of the imaging technique, such as angle dependency, sample volume, and tethering artifacts as well as to shortcomings inherent to derivation of pressures from inflow or re-extension signals .Furthermore, the reliability, feasibility, and practical utility of the individual markers of diastolic dysfunction have been questioned and concordance has been shown to be poor , 4. WithOur group has previously shown that a combined assessment of both early and late diastolic velocities by colour TDI is a strong prognostic marker of acute myocardial infarction, heart failure, and cardiovascular death in the general population . This inThe aims of this study are to investigate: 1) The potential of colour TDI determined total diastolic LD in the determination of diastolic function in the healthy and dysfunctional heart, 2) The ability of total diastolic LD to predict adverse outcomes, 3) To assess reproducibility of total diastolic LD.The Department of Cardiology, Herlev and Gentofte Hospital, University of Copenhagen performs routine echocardiograms according to a standardised protocol and these echocardiograms are stored on a local server.A total of 486 consecutive patients were retrieved from the echocardiogram database. To obtain a representation of structural heart disease , the echocardiograms were analysed in accordance with the following criteria:No cardiac abnormalities: Eyeball LVEF >50 % and normal cardiac dimensions.Severe systolic heart failure: Eyeball LVEF <30 %.2 for women and ≥131 g/m2 for men.LV hypertrophy: LV mass/body surface area ≥113 g/m2 for women and ≥3.7 cm/m2 for men.LV dilation: LV internal dimension at end-diastole/body surface area ≥3.8 cm/mMitral regurgitation: ≥grade 2.Inclusion criteria:Overlapping diseases of the above mentioned, for example, mitral regurgitation in a patient with LV hypertrophy. Exceptions: patients with a dilated LV, hypertrophic LV, or mitral regurgitation may have had a LVEF under 30 %.Incomplete examinations.Bundle branch block.Atrial fibrillation.Unsuitability for colour TDI, i.e. indistinguishable E- and A-wave.Exclusion criteria:n = 45), LV hypertrophy (n = 49), LV dilation (n = 30), and mitral regurgitation (n = 33). Diastolic function was assessed and participants were graded as having a normal relaxation (n = 76), abnormal relaxation (n = 75), pseudonormal relaxation (n = 44), or restrictive filling pattern (n = 11).A total of 89 patients fulfilled inclusion criteria for “no cardiac abnormalities”; 138 patients fulfilled inclusion criteria for “severe systolic heart failure”; 117 patients fulfilled criteria for “LV hypertrophy”; 75 patients fulfilled inclusion criteria for “LV dilation”; and 67 patients fulfilled criteria for “mitral regurgitation”. After application of exclusion criteria, the final study population consisted of 206 patients, 49 of whom were classified as having normal cardiac dimensions and function. The 157 remaining patients all had heart anomalies that could potentially affect diastolic LD such as severe systolic heart failure  and all images were stored digitally on a central server. All participants were examined with conventional two-dimensional echocardiography, m-mode, pulsed-wave TDI, colour TDI and two-dimensional strain imaging. All the echocardiographic analyses in the present study were performed de novo and offline  using Echopac BT11 software .LV end-diastolic dimensions , LV internal dimension (LVID), and LV posterior wall thickness (PWT)) and LA diameter were obtained from the parasternal long-axis view at the mitral valve leaflet tips. Pulsed wave Doppler was used to record mitral inflow between the tips of the mitral leaflets. LVEF was obtained using modified Simpson’s biplane method in the 4-chamber and 2-chamber view . LA voluColour TDI loops were obtained in the apical 4-chamber view. Peak longitudinal systolic velocities (s’) as well as early diastolic (e’) and late diastolic (a’) velocities were measured in the septal and lateral wall using a 5 mm circular sample volume placed in the left ventricular myocardial just proximal to the mitral annular level. Total average systolic and diastolic LD was determined by calculating the area under the curve, using tissue tracking software, of the systolic, early and late diastolic waves, respectively, and averaging septal and lateral findings Fig. . PotentiPulsed wave TDI tracings, used to measure peak myocardial velocities, were obtained with the range gate placed at the septal and lateral mitral annular segments in the 4-chamber view. The average of septal and lateral e’ by pulsed wave TDI was used to calculate E/e’.Mitral annular plane systolic excursion (MAPSE) was determined in the septal and lateral walls in the apical four-chamber view in all participants. This was done by placing the M-mode cursor in the septal and lateral borders in the mitral annular plane. In doing so, an image of either septal or lateral mitral annular displacement was obtained. MAPSE was measured from the lowest to the highest point of contraction, excluding post-systolic contractions, i.e. measurements were obtained between aortic valve opening and aortic valve closure.Using 2-dimensional speckle tracking derived strain imaging, the left ventricular myocardial wall was traced in the 4-chamber view with the basal septal and lateral segments starting at the mitral annular level. By the tracking of speckles from frame-to-frame, myocardial deformation was assessed. The average of regional measurements in a 6-segment model from the apical 4-chamber view was used as an estimate of longitudinal displacement (LD), longitudinal strain (LS) and longitudinal strain rate (LSR). Regional basal longitudinal displacement, strain, and strain rate was calculated as the average of the basal septal and lateral segments in the apical 4-chamber view.TDI and strain measurements are reported as absolute values.Patients were graded as having either normal diastolic function or abnormal diastolic function grade 1–3 according to current EAE/ASE recommendations .Data on mortality (primary endpoint) was obtained using the unique personal identification number in the Central Office of Civil Registration and the Danish National Board of Health’s National Patient Registry.t-test and χ2-test, respectively. Pearsons correlation was used to determine any associations between the degree of diastolic dysfunction and total average diastolic LD as well as between total average diastolic LD and individual parameters used in the assessment of diastolic and systolic function. Using logistic regressions, odds ratios for unadjusted and adjusted models were calculated to establish the association between peak velocities and diastolic LD and the primary endpoint (death). Interactions with the subgroup type were tested for. Bland-Altman analysis was used to evaluate intraobserver and interobserver variability and was expressed as mean difference ± 1.96 standard deviation (SD) and as coefficient of variation (CV) [P-values <0.05 in two-sided tests were considered statistically significant.All statistical analyses were done using SPSS version 20 . In Table ion (CV) . P-valueMain characteristics of the study population are presented in Table p-value <0.001. Using linear regression, total average diastolic LD was estimated to fall by 2.4 mm for every increase in graded severity of diastolic dysfunction . A similar relationship was found when investigating total average diastolic velocity (e’ + a’) and degree of diastolic function , although a cutoff of 12 cm/s is appropriate here  = 10.7 ± 1.5 mm). Systolic function of individuals with severe systolic heart failure, normal diastolic function, and a diastolic LD <10 mm was also reduced, but to a greater degree .Figure Generally, median values of mean diastolic LD fell with increasing severity of diastolic dysfunction for all subgroups except for the control group and patients with LV hypertrophy, who both had a preserved total average diastolic LD ≥10 mm despite being categorised as having an abnormal relaxation pattern. Median values of all participants classified as having either a pseudonormal or restrictive filling pattern had a total average diastolic LD <10 mm. Table 2).A further analysis of controls with grade 1 diastolic dysfunction and a diastolic LD ≥10 mm revealed that the sole reason for these individuals being classified as having grade 1 diastolic dysfunction was a lateral e’ <10 cm/s or septal e’ <8 cm/s and not enlarged atriums .Table Figure By examining the colour combinations of subjects in Fig. −1, TT-s’ = 9.2 ± 1.8 mm and s’ = 4.8 ± 1.0 cm/s compared to LS = −13.9 ± 3.9 %, LSR = −1.05 ± 0.32 s−1, TT-s’ = 11.9 ± 2.2 mm and s’ = 6.3 ± 1.4 cm/s.Regarding subjects with a LVEF >50 % and a diastolic LD <10 mm, it can be seen that almost all subjects have some degree of diastolic dysfunction. A comparison of longitudinal systolic function of these subjects, i.e. patients with LVEF >50 % and diastolic LD <10 mm (n = 32), compared to subjects with LVEF >50 % and diastolic LD >10 mm (n = 88) revealed that systolic function was reduced in this group: LS = −12.3 ± 4.1 %, LSR = −0.86 ± 0.33 s−1, TT-s’ = 10.8 ± 1.5 mm and s’ = 5.3 ± 1.2 cm/s. An analysis of the comorbidities of these patients revealed that they all suffered from ischemic heart disease.An examination of systolic function of the 4 individuals with a LVEF <50 % and a diastolic LD >10 mm revealed a LS of −11.5 ± 7.1 %, LSR = −0.78 ± 0.17 sPearsons correlation was used to determine the association of average diastolic LD with a variety of other echocardiographic parameters Table . With reFigure There were 33 events (death) during 2.6 ± 1.2 years follow-up. Odds ratios were calculated to determine the predictive capabilities of total diastolic LD in comparison to diastolic colour TDI velocities with regards to all-cause mortality: per unit decrease, risk of death increased in a similar pattern for e’ + a’ and TT-e’ + TT-a’  can have a preserved diastolic function as, with regards to conventional understanding, a reduced systolic function should result in a reduced diastolic function and vice versa. A closer inspection of these patients revealed that the individuals with a diastolic LD >10 mm had reduced markers of systolic function, though greater than individuals with a diastolic LD <10 mm.) reveals broad E-waves and tall, narrow A-waves. For subjects with LV hypertrophy and grade 1 and 2 diastolic dysfunction , systolic LD (TT-s’), M-mode derived MAPSE and 2D strain derived LD Table . This fiDespite acceptable correlations between total average diastolic LD and measurements of systolic heart function Table , it can Average systolic LD was found to slightly underestimate total average diastolic LD by approximately 0.6 mm Fig. . Even thFurthermore, as is shown in Table Reproducibility of displacement measurements of E- and A-waves was reasonable, taking into consideration that this is the first time that diastolic LD by colour TDI has been validated, and was fairly equal in the determination of both intra and interobserver variability. Limits of agreement were fairly wide and the largest variability was seen in the determination of displacement of the lateral A-wave.An analysis of death as an endpoint, using odds ratios and ROC curve analyses, showed that risk of death per unit decrease in both average diastolic LD (TT-e’ + TT-a’) and average peak diastolic velocities (e’ + a’) was similar, even after adjustment for covariates.Total average diastolic LD has the potential to revolutionise the way in which we look at diastolic function. It looks at the entire diastolic process, therefore, making it a promising and sensitive marker of diastolic function. Furthermore, it has the potential to be used in a clinical setting as a quick and effective determinant of patients with and without diastolic dysfunction.A variety of limitations in this study have to be addressed:Firstly, the validity of total average diastolic LD was measured against determinants from current guidelines for the non-invasive determination of diastolic dysfunction as the golden standard. Future research with the use of invasive diastolic measurements is, therefore, required.Secondly, only the septal and lateral wall in the 4-chamber view was assessed. A truer  depiction of global longitudinal diastolic performance would be obtained if the anterior, inferior, posterior and anteroseptal mitral annular sites were included.Thirdly, all-cause mortality was the only primary endpoint evaluated in this study. An assessment of more endpoints, including cardiovascular death, may show the prognostic value of total average diastolic LD to be even higher.Total average diastolic LD is a promising alternative to current algorithm-based evaluations. It has a linear relationship with the degree of diastolic dysfunction assessed by current guidelines and a 10 mm threshold in total average diastolic LD can potentially be used independently to evaluate patients with and without diastolic dysfunction in a variety of different heart conditions with reasonable intra and interobserver reproducibility.


The prevalence of end-stage heart failure (HF) is on the increase, however, the availability of donor hearts remains limited. Left ventricular assist devices (LVADs) are increasingly being used for treating patients with end-stage HF. LVADs are not only used as a bridge to transplantation but also as a destination therapy. HeartMate II, a new-generation, continuous-flow LVAD (cf-LVAD), is currently an established treatment option for patients with HF. Technological progress and increasing implantation of cf-LVADs have significantly improved survival in patients with end-stage HF. Here we report a case of a patient with end-stage HF who was successfully supported using cf-LVAD implantation with adjuvant tricuspid valve repair in a general district hospital. HeartMate II is a new-generation, continuous-flow left ventricular assist device  used as a bridge to transplantation (BTT) and as a destination therapy (DT) in patients with end-stage heart failure (HF).The use of implantable mechanical circulatory support devices, such as cf-LVAD, has increased in recent years.2, had suffered from advanced HF following dilated cardiomyopathy, and had been waiting for a heart transplant for four years. In addition, he had diabetes mellitus requiring insulin control. On examination, he exhibited bilateral grade IV pitting oedema of the lower limbs with bilateral pleural effusion and ascites.A 39-year-old man was admitted to our hospital because of deteriorating heart function despite maximal medical treatment. He had a body surface area of 1.88 mLaboratory tests showed a total bilirubin level of 6.2 mg/dl, aspartate aminotransferase level of 109 U/l, and blood creatinine level of 1.8 mg/dl. Echocardiography revealed a left ventricular (LV) diastolic diameter of 67 mm, LV systolic diameter of 58 mm, and ejection fraction of 19% with severe tricuspid regurgitation (TR).2, respectively. This facilitated optimising the use of dobutamine and dopamine to decrease the right ventricular (RV) afterload while maintaining ventricular contractility. An intra-aortic balloon pump was inserted at the same time because the urine output had decreased. Furosemide was continuously administered to obtain an adequate urine output and to decrease central venous pressure to < 24 mmHg. Right ventricular failure (RVF) is common after cf-LVAD implantation and is a leading cause of morbidity and death after cf-LVAD implantation.A pulmonary artery catheter was inserted to measure pulmonary artery systolic pressure, pulmonary capillary wedge pressure, central venous pressure and cardiac index, which were found to be 34, 50 and 36 mmHg, and 0.5 l/min/mFive days after admission, tricuspid valve repair was performed using the de Vega annuloplasty procedure under anaesthesia. HeartMate II was implanted under cardiopulmonary bypass. The alignment of the mitral valve and inflow cannula was checked using transoesophageal echocardiography.Initial pump flow was at 6 000 rpm, and we gently needlepunctured the cf-LVAD outflow tract to assist in de-airing the intracardiac air bubbles. The needle and clamp were removed, cardiopulmonary bypass was terminated, and the pump speed was increased from 6 000 to 9 200 rpm; the pump flow was 4.5 l/m, pulse index was 5.7, pump power was 5.5 W, and mean blood pressure was 60 mmHg. Protamine was administered slowly. The intra-aortic balloon pump was removed, and an open repair of the left femoral artery was performed. Dobutamine and dopamine maintained the RV contractility and decreased the RV afterload.The patient’s condition stabilised, and he was transferred to the intensive care unit. The endotracheal tube was removed the next day. More than 12 hours following cf-LVAD implantation, when the chest tube drainage decreased to ≤ 50 ml/h and the coagulation profile returned to normal levels, an intravenous heparin infusion was started to maintain activated partial thromboplastin time between 50 and 70 s. Aspirin (100 mg) was administered once daily after extubation, and warfarin was administered to maintain the international normalised ratio (INR) between 2.0 and 3.0. Heparin infusion was continued until the INR target range was attained. He was discharged one month after the operation and was categorised as New York Heart Association functional class II.The prevalence of end-stage HF is on the increase, however, the availability of donor hearts remains limited. Therefore, the number of patients requiring long-term support with cf-LVAD implantation has increased. HeartMate II is a new-generation cf-LVAD used as BTT and DT in patients with end-stage HF.3The waiting time for cardiac transplant recipients has increased, and so has BTT by using the support device in clinical settings. We occasionally encounter patients who require unexpected long-term device support. In addition to being a life-saving treatment, cf-LVADs currently also provide long-term survival with favourable quality of life for patients with severe HF. Consequently, long-term cf-LVAD implantation has become a valuable alternative to cardiac transplantation for treating end-stage HF.Studies have reported that post-transplant survival at one, two, five and 10 years is approximately 90, 80, 70 and 50%, respectively.4Prolonged post-transplant survival in patients receiving BTT can reduce the need for cardiac transplantation as a first-line replacement therapy. However, it is too premature to draw conclusions about survival comparisons because of the lack of head-to-head comparative data. Furthermore, considering the frequent readmissions in this population, patient survival, quality of life, and healthcare costs should be considered before drawing conclusions.1Despite this progress, cf-LVAD implantation is still associated with a risk of complications, which challenges patient selection and adversely impacts on outcomes. The incidence of RVF in this population ranges from 10 to 50% and is a risk factor for peri-operative and postoperative mortality and morbidity in patients undergoing cf-LVAD implantation.5Moreover, some reports have suggested that cf-LVAD implantation in patients with pre-operative hepatic failure entails considerable mortality.2 cf-LVAD recipients who develop postoperative RVF have poor outcomes, including increased incidences of multi-organ failure, postoperative haemorrhage, pulmonary complications, thromboembolic events, and migration of intracardiac air to the coronary arteries, causing transient myocardial ischaemia.In a previous study, 33.4% of patients experienced RVF postoperatively and 10–15% required RV support.5The prediction and treatment of RVF are crucial to improve survival after cf-LVAD implantation. The ratio of central venous pressure to pulmonary capillary wedge pressure and secondary pulmonary hypertension is a critical predictor of RVF after cf-LVAD implantation; RVF significantly reduces survival after cf-LVAD implantation.Furthermore, secondary TR is common among patients with RVF who undergo cf-LVAD implantation. Although the repair of TR in combination with cf-LVAD implantation is not an established approach, recent reports have suggested that concomitant tricuspid valve repair may reduce postoperative RVF.HeartMate II may transiently worsen the right ventricular function in the initial post-implant period because of a higher cardiac output resulting in increased venous return and right ventricular preload.Survival rates have increased because major adverse events, such as stroke, bleeding and infection, have decreased. The occurrence of thrombosis ranges from annualised rates of 2–4% and that of haemolysis ranges from 2–3%.Some reports have evaluated heparin antibodies, aspirin resistance and baseline platelet function where possible.The management of bleeding is indivisibly linked to the risk of thromboembolic events, and anticoagulation and antiplatelet therapies seem to be the only methods for carefully managing complication and individual risks. Further understanding of the mechanisms underlying bleeding and novel strategies, such as new anticoagulant drugs, are expected to play crucial roles in the long-term management of cf-LVAD therapy.1Cardiac arrhythmia, such as ventricular arrhythmia, is also a common issue in the early and late periods after cf-LVAD implantation. Although such arrhythmias may not be lethal in the presence of cf-LVAD, it could put patients at a risk of RVF.1End-organ function was restored one month after the initiation of support.1The implantation of cf-LVAD, either as BTT or DT, remains a critical treatment option for selected patients with end-stage HF.


In sepsis, tachycardia may indicate low preload, adrenergic stimulation, or both. Adrenergic overstimulation is associated with septic cardiomyopathy. We sought to determine whether tachycardia was associated with left ventricular longitudinal strain, a measure of cardiac dysfunction. We hypothesized an association would primarily exist in patients with high preload.E/e′). We assessed correlation between strain and heart rate in patients with low preload (E/e′ < 8), intermediate preload (E/e′ 8–14), and high preload (E/e′ > 14), adjusting for disease severity and vasopressor dependence.We prospectively observed septic patients admitted to three study ICUs, who underwent early transthoracic echocardiography. We measured longitudinal strain using speckle tracking echocardiography and estimated preload status with an echocardiographic surrogate (p = 0.001). After adjusting for vasopressor dependence, disease severity, and cardiac preload, we observed an association between heart rate and longitudinal strain . This association persisted among patients with high preload  and in patients with shock , but was absent in patients with low or intermediate preload and those not in shock.We studied 452 patients, of whom 298 had both measurable strain and preload. Abnormal strain (defined as >−17%) was present in 54%. Patients with abnormal strain had higher heart rates  contains supplementary material, which is available to authorized users. Sepsis is a common and often lethal state of extreme disruption of homeostasis in the face of severe infection , 2. AdmiCatecholamines are a key mediator of baroreflex function, by which the autonomic nervous system optimizes cardiac output and blood pressure through adjustments in heart rate, contractility, and vascular tone. Early in sepsis, tachycardia may merely reflect appropriate baroreflex activity . In septHistorically, cardiac function in sepsis has been assessed primarily by left ventricular ejection fraction (LVEF). However, LVEF is highly load dependent and therefore less reliable in assessment of cardiac function in states of low preload or low afterload –21. In tGiven the improved ability to detect septic cardiomyopathy provided by the development of LV strain imaging techniques, we have a new opportunity to investigate the relationship between hyperadrenergic states in sepsis and septic cardiomyopathy. We hypothesized that in septic patients with adequate or increased preload, tachycardia would be associated with worse ventricular strain, suggesting the possibility that hyperadrenergism, manifested by increased heart rate in the absence of low preload, is associated with septic cardiomyopathy, while tachycardia in low-preload states would not be associated with impaired LV strain.Study Design: This prospective, observational study was conducted at three intensive care units (ICUs) at two study hospitals, Intermountain Medical Center and Beth Israel Deaconess Medical Center. In these ICUs, transthoracic echocardiography (TTE) is routinely performed on patients with sepsis or septic shock at the time of ICU admission. The protocol was approved by the Intermountain Healthcare Institutional Review Board with a waiver of informed consent and by the Beth Israel Deaconess Medical Center Institutional Review Board with oral informed consent.We screened patients between October 2012 and November 2015 admitted with severe sepsis or septic shock defined by the then-current 1992 American College of Chest Physicians/Society of Critical Care Medicine consensus criteria , and opeWe calculated Acute Physiology and Chronic Health Evaluation, 2nd version (APACHE II)  and SequE/e′) to assess left ventricular preload [E/e′ < 8, a high-preload state as >14, and an intermediate-preload state as 8–14 [Transthoracic echocardiograms (TTEs) were performed by a cardiac sonographer or a physician echocardiographer, using a Philips iE-33 or CX-50 . Patients were excluded if their TTE occurred more than 24 h after ICU admission or if the image quality was so poor as to be uninterpretable. All echo readers were blinded to clinical outcomes, and all final interpretations were performed by Level II echocardiographers who are testamurs of the National Board of Echocardiography Adult Comprehensive Exam. Longitudinal strain was measured independently from preload assessment, to avoid possible bias. We used the Image-Arena platform  to perform semiautomated speckle tracking for left ventricular longitudinal strain. We selected standard apical four-chamber views for strain analysis. All strain analyses were performed by advanced cardiac sonographers or physicians who had already performed >100 h of speckle tracking analysis. We selected the best available single cardiac cycle with regard to image quality and measured longitudinal strain of the endocardium. We rejected images due to poor image quality if we could not track two or more adjacent segments in the apical four-chamber view. We defined abnormal strain as greater than −17% (higher numbers are worse) in accordance with previously published literature describing patients with septic shock , 46. Bec preload , 47, 48. as 8–14 , 50. In  as 8–14 .E/e′), and admission APACHE II. To better understand the relevance of preload in this analysis, we secondarily fit separate regression models (controlling for vasopressor infusion rate and APACHE II) for patients with low preload, intermediate preload, or high preload.Our prespecified primary analysis was a linear regression of LV longitudinal strain on heart rate, while controlling for vasopressor infusion rate, preload , and whether they met criteria for abnormal strain (>−17%). Low-, intermediate-, and high-preload patients were analyzed using Kruskal–Wallis tests for comparisons of central tendencies, while Wilcoxon rank sum tests were used to compare patients with and without shock, as well as those with and without abnormal strain. Fisher’s exact tests were used to compare proportions for all three analyses. Statistical analyses were performed using the R Statistical Package, version 3.0.2 .E/e′ , but no difference in heart rate . Fifty-four percent of the patients in the primary analysis had abnormal strain, and 36% had high preload (E/e′ > 14). Patients with abnormal strain had higher heart rates . We noted no difference between patients with shock and without shock in regard to heart rate , ejection fraction , or strain . Patients in shock had a lower E/e′  than those without shock .Our study population comprised 452 patients, of whom 392 (87%) had adequate echocardiographic image quality to measure longitudinal strain and 338 (75%) had a measureable /e′ Fig. . Seventyp = 0.08). Patients with low preload had lower stroke volume, and patients with higher preload received less fluid  or intermediate preload (p = 0.19). In an exploratory analysis, we evaluated the expected negative correlation between ejection fraction and strain . We observed an association between ejection fraction and heart rate in patients with high preload  that was absent in patients with low preload (p = 0.80) or intermediate preload (p = 0.87). We observed a similar association between strain and heart rate among patients with shock  that was absent in non-shock patients . We found no difference in hospital mortality or in cardiovascular-, hepatic-, or coagulation-failure-free days between patients with normal strain versus patients with abnormal strain  decreased ejection fraction or stroke volume (which can occur with either high or low ejection fraction) , (b) newOur proportion of patients with septic cardiomyopathy compares similarly to other published cohorts , 46, 60.E/e′ is an imperfect surrogate for left ventricular preload or hypovolemia [E/e′. Our regression models included age as a component of APACHE II score, and a sensitivity analysis including age as a separate covariate demonstrated age was not significantly associated with strain. Among critically ill patients, particularly an elevated E/e′ may be difficult to interpret. An increased E/e′ might reflect impaired myocardial diastolic function but could also result from hypervolemia with normal myocardial diastolic function. In addition, while E/e′ > 14 accurately identifies patients with high cardiac preload, E/e′ < 14 may be difficult to interpret [E/e′ is associated with lower filling pressures, a low E/e′ does not necessarily indicate hypovolemia. This large zone of uninterpretable values for E/e′ underlies the rejection of E/e′ as the sole measure of diastolic function in the ASE 2016 definitions, although use of the septal E/e′ as a sole measure of diastolic function has been studied in the critically ill [E/e′ rather than the average of septal and lateral E/e′ due to image availability and based on previously published data suggesting adequate accuracy [E/e′ more difficult to compare to values published using the average of septal and lateral.We acknowledge that ovolemia . Age, minterpret . While aally ill . In addiaccuracy . This maAlternative measures of assessing cardiac preload are available, although many have limitations, and there is no clinically available gold standard. In the contemporary ICU, it is exceedingly uncommon to place pulmonary artery catheters in septic patients to assess preload. Dynamic parameters such as pulse pressure variation, aortic velocity variation, or vena cava variation depend on passive mechanical ventilation, which is also uncommon in contemporary ICUs . The resE/e′, shock index, and central venous pressure. A composite of these measurements may outperform a single surrogate measurement [Future scientific inquiry in this field may benefit from a composite of several available surrogates of cardiac preload, including dynamic parameters, passive leg raise, surement . PerhapsOur study differs from other echocardiographic studies of septic patients in that the echoes were performed very early in the course of sepsis. Several other studies of septic patients performed echocardiography much later, around 24–48 h after the sepsis onset , 65–67. and high preload supports this model and is the main contribution of this study.The observed association between tachycardia and LV systolic dysfunction can be explained by multiple mechanisms. In low-preload states, tachycardia may be a compensatory response to reduced cardiac preload to maintain cardiac output . HoweverIt is possible that profound vasoplegia and its treatment with vasoactive medications might be driving septic myocardial dysfunction , 74, altOne notable feature of tachycardia in sepsis is that the observed myocardial dysfunction may arise from a perturbation in the force–frequency and frequency-dependent acceleration of relaxation (FDAR) mechanisms, whereby tachycardia my worsen contractility due to decreased reuptake of calcium in the sarcoplasmic reticulum . This meE/e′ may be more representative of ventricular elastance than ventricular volumes per se. However, E/e′ has been demonstrated to correlate well with left ventricular end-diastolic pressures and can be easily obtained in most patients with interpretable echo images [E/e′ components of the echo separately. The inclusion of both patients receiving and not receiving mechanical ventilation and vasopressor infusions also increases the generalizability of the study.While marked by a large sample size and echocardiography performed during the early phase of sepsis most relevant to therapeutic interventions, our study nevertheless has limitations. Our definition of cardiac preload on the basis of LV diastolic filling patterns is an imperfect surrogate for left ventricular end-diastolic volume. o images , 47, 48.o images , althougo images –40, haveo images . Althougo images , 68. We o images . Importao images , 46, 60.Tachycardia is associated with impaired LV strain, a sensitive marker of cardiomyopathy, in septic patients with high cardiac preload.


However, some of these therapies may reduce edema, leading to an underestimation of the AAR by T2-CMR. Here, we investigated arterial spin labeling (ASL) perfusion CMR as a novel approach to quantify the AAR following AMI. Adult B6sv129-mice were subjected to in vivo left coronary artery ligation for 30 minutes followed by 72 hours reperfusion. T2-mapping was used to quantify the edema-based AAR (% of left ventricle) following ischemic preconditioning (IPC) or cyclosporin-A (CsA) treatment. In control animals, the AAR by T2-mapping corresponded to that delineated by histology. As expected, both IPC and CsA reduced MI size. However, IPC, but not CsA, also reduced myocardial edema leading to an underestimation of the AAR by T2-mapping. In contrast, regions of reduced myocardial perfusion delineated by cardiac ASL were able to delineate the AAR when compared to both T2-mapping and histology in control animals, and were not affected by either IPC or CsA. Therefore, ASL perfusion CMR may be an alternative method for quantifying the AAR following AMI, which unlike T2-mapping, is not affected by IPC.T Myocardial salvage, which controls for the variability in area-at-risk (AAR) between patients, is a more sensitive measure of cardioprotective efficacy than MI size alone, but it requires the quantification of the AAR in AMI patients4. In this regard, T2-weighted cardiovascular magnetic resonance (CMR) of the heart has been shown to retrospectively quantify the AAR in clinical cardioprotection studies8. This technique is based on the ability of T2-weighted CMR to detect the myocardial edema that results from acute ischemia-reperfusion injury (IRI)9. The area of myocardial edema delineated by T2-weighted CMR has been shown to correspond to the AAR quantified by classical histological staining methods in animal AMI models13, and the AAR measured by coronary angiography jeopardy scores14, myocardial single-photon emission computed tomography (SPECT) imaging15 and positron emission tomography using 18F-fluorodeoxyglucose16.Novel therapies are still needed to reduce myocardial infarct (MI) size and prevent the onset of heart failure in patients presenting with an acute myocardial infarction (AMI)2-CMR for quantifying the AAR, the validity of this CMR technique for quantifying the AAR has been questioned17. Furthermore, recent clinical studies have found that, in addition to limiting MI size, some cardioprotective interventions (such as ischemic postconditioning18 and remote ischemic conditioning8) may actually reduce the extent of myocardial edema leading to underestimation of the AAR measured by T2-CMR, thereby obviating the use of this technique for measuring myocardial salvage in these settings. Therefore, a more robust method for quantifying the AAR, which is not affected by the cardioprotective intervention under investigation, is required.Despite the promising application of Tin vivo assessment of MI pathology using CMR. Late-gadolinium enhancement (LGE), T2 mapping and arterial spin labeling (ASL) perfusion mapping CMR were assessed in the presence of two well-known cardioprotective therapies that have consistently been shown to reduce MI size in the pre-clinical setting, namely ischemic preconditioning (IPC) and cyclosporin-A (CsA). We aimed to investigate the accuracy of ASL perfusion CMR mapping against T2-mapping CMR and histology for delineating the AAR following interventions by IPC and CsA.In the current study, we perform a multi-parameter ex vivo histological staining was used to validate the IRI model and efficacy of cardioprotective interventions used in this study.Initial comparison of AAR and MI size quantified by ex vivo histological staining  determined by The short axis stacks of cine images were analyzed to measure left ventricular mass, end-systolic volume, end-diastolic volume, stroke volume, ejection fraction and cardiac output Fig. . The lef2 mapping, ASL perfusion mapping (1 SD threshold) and T1 mapping are provided in Supp. Table 2, perfusion and T1 values.MR images and histological staining from an example data set are shown in Fig. in vivo and ex vivo images of transverse myocardial slices.Previously validated LGE and histological staining were compared between LGE of mouse hearts subjected to control IRI revealed clearly defined regions of signal enhancement within the left ventricle Fig. . Quantifin vivo quantification of MI size. There was no significant difference between MI size quantified by in vivo LGE and ex vivo TTC staining for animals treated with IPC  was qualified as the putative AAR by comparison with ex vivo stained myocardial slices. Quantification of the putative AAR by T2-mapping (AAR as a fraction of LV area: AAR/LV%) in mice subjected to control IRI showed good agreement between T2-mapping and histological staining . Bland-Altman analysis provided a small bias of 4.0% . Bland-Altman analysis provided a bias of −9.1% . Bland-Altman analysis demonstrated a bias of 4.0%, which is equivalent to control and vehicle groups  was qualified as the putative AAR for this study. Perfusion deficits were compared with histological analysis of 6 ex vivo stained myocardial slices.ASL perfusion maps of mouse hearts subjected to control IRI revealed clearly defined regions of decreased perfusion within the left ventricle Fig. . This suQuantification of the putative IS/LV% by ASL perfusion mapping in mice subjected to control IRI using the 2 SD threshold showed good agreement between ASL perfusion mapping and histological staining  or 2 SD threshold (putative IS), there was no significant difference in the mean perfusion value in areas deemed ‘normal’ or ‘reduced’ perfusion threshold  The cardioprotective intervention, IPC, but not CsA, reduced the extent of myocardial edema on T2 maps, leading to an underestimate of the AAR in IPC-treated hearts; (3) ASL perfusion mapping performed 3 days following an acute MI showed reduced perfusion outside the MI zone and could also accurately quantify the AAR in the murine heart in the absence of a cardioprotective intervention; and (4) Unlike T2-mapping, the AAR measured by ASL perfusion mapping was not affected by either IPC or CsA, suggesting that ASL perfusion mapping may be a more robust method for the in vivo quantification of the AAR in cardioprotection studies.The major findings of the current study are as follows: (1) T3.The reliable and accurate measurement of the AAR is required to assess myocardial salvage in clinical studies investigating novel cardioprotective interventions in acute MI patients. The current ‘gold-standard’ for achieving this is by myocardial SPECT imaging but this technique has a number of disadvantages including a substantial ionizing radiation exposure, requires round the clock access to a radioactive isotope and it suffers with poor resolution2-mapping has emerged as a technique for retrospectively quantifying the AAR in acute MI patients19. This has been validated against AAR measured by classical histological methods in animal AMI models13, and in patients it has been compared to AAR determined by angiography jeopardy scores14 and myocardial SPECT imaging15. However, T2-mapping is an indirect method for delineating the AAR, which relies on the detection of myocardial edema within the AAR. Although it is known that myocardial edema develops in response to acute IRI, the underlying pathophysiology and its time-course in the reperfused heart remain unclear9. Furthermore, recent clinical studies have demonstrated that certain cardioprotective interventions may reduce the extent of myocardial edema delineated by T2-mapping resulting in an underestimate of the AAR by this method. Thuny et al.18 found that in those STEMI patients randomized to receive ischemic postconditioning (IPost) , the extent of myocardial edema imaged by T2-mapping was reduced by 32%. Reductions in myocardial edema imaged by T2-weighted and T2-mapping have also been reported in clinical studies investigating the cardioprotective intervention remote ischemic conditioning (RIC) (cardioprotection induced by transient limb ischemia)8. In our study, we show for the first time that the cardioprotective intervention, IPC, reduced the extent of myocardial edema imaged by T2-mapping in a murine AMI model, consistent with the notion that ‘ischemic conditioning’ reduces myocardial edema as well as limiting MI size.In its place, T1 and T2-mapping provided a reasonably accurate quantification of AAR in the murine AMI model. This suggests that despite the cardioprotective effect of CsA in reducing MI size, it does not appear to affect the development of myocardial edema. This could perhaps be taken as evidence that these interventions exert differential protective effects against acute IRI. The potential differential effects of IPC and CsA on the extent of myocardial edema could provide support for the previous clinical studies which showed that the mechanical interventions, IPost and RIC, but not the pharmacological intervention metoprolol6 or exenatide7 reduced myocardial edema on T2-mapping. However, these early studies do not provide sufficient evidence of a mechanistic difference between these mechanical and pharmacological interventions for which extensive further studies are now required and are beyond the scope of this proof-of-concept study.Interestingly, CsA did not affect the area of myocardial edema and T2-mapping to delineate the AAR, we performed a multi-parametric CMR study to investigate in vivo quantification of the AAR in the reperfused heart. In addition to standard LGE and T2 mapping, this study examined the use of a contrast-free ASL perfusion mapping approach to evaluate tissue perfusion in reperfused mouse hearts. In humans, perfusion-based cardiac CMR has mainly examined the use of first-pass perfusion imaging where the perfusion of a contrast agent is used to identify areas of differential perfusion. The success of contrast perfusion methods in the mouse heart has been limited by the spatial and temporal resolution due to its small size and rapid heart rate. The multi-slice ASL sequence used in this study has been extensively optimized for in vivo imaging of the mouse myocardium21. The studies undertaken in here represent the first application of a cardiac ASL sequence for the multi-slice assessment of acute MI.Given the problems associated with using T22 used single slice ASL for myocardial perfusion assessment following an IRI model with 1 hour of occlusion and visually compared perfusion deficit to area of infarction (IS). Using a single slice acquisition, a “normal perfusion” region is not available for calibration, therefore it is not possible to assess the percentage of tissue exhibiting deficit to determine if this is AAR or infarct region. In our study, quantification of the area of myocardium exhibiting decreased myocardial perfusion (according to a 1 standard deviation threshold) displayed good agreement with the AAR calculated by histological staining for all groups. Quantification of IS from ASL perfusion mapping (according to a 2 standard deviation threshold) was also possible, but was subject to substantially increased variability within groups. The T1 maps used to generate ASL perfusion measurements also showed underestimation of AAR in the IPC group, indicating that putative AAR measured by ASL perfusion mapping is not simply mirroring T1 measurements of edema. Potentially confounding factors such as partial volume, resolution limits and T1 and T2 contributions to ASL signal will be investigated in more detail in future studies. This study provides the first suggestion that multi-slice ASL perfusion mapping may provide a means to determine myocardial AAR in reperfused hearts.ASL perfusion maps of the reperfused myocardium showed spatially distinct regions of reduced tissue perfusion. Given that the total area of perfusion deficit was always larger than the area of infarction, it is unlikely that the measurement here reflects decreased perfusion within the infarcted area only, although perfusion is further reduced in infarcted tissue. One previous studyThe reduced perfusion within the AAR is not expected to correspond to unsuccessful reperfusion of the LAD coronary artery in this model but most likely represent some impairment of microvascular perfusion within the capillary bed of these hearts. The biological basis of the perfusion deficit identified within the myocardial AAR has not been investigated here and is beyond the scope of this proof-of-concept study. It is worth noting that the ASL perfusion mapping generated more variability than other metrics in the IPC group. This study showed that neither IPC nor CsA significantly affected the quantification of AAR by ASL perfusion mapping, thereby showing promise as a more robust CMR technique for delineating the AAR. Further studies are required to compare these perfusion measurements with SPECT or microsphere perfusion measurements and validate these findings in IRI models.Interestingly, we found that there was no significant effects of the cardioprotective treatments IPC and CsA on cardiac volumes and function, although there was a small reduction in LV mass with CsA. There may have been no effects of IPC and CsA on cardiac volumes as this was assess at 3 days post-MI and this may have been too soon to have seen any beneficial effects on LV remodeling. The failure to observe any significant improvement in cardiac function with IPC and CsA may be explained, in part, by the variability in cardiac function, the effect of myocardial stunning (reversible cardiac dysfunction), and the relatively small sample sizes.ex vivo hearts) and different contractile states.It is possible that other cardioprotective interventions may affect the validity of AAR quantification by ASL perfusion mapping. It may be expected that if an intervention were to modify myocardial perfusion that this may in turn affect the calculation of AAR by ASL perfusion mapping, since this method is based on detection of a perfusion deficit. Indeed, nitrate treatment has been shown to improve myocardial perfusion in reperfused canine hearts. Interestingly, analysis of myocardial perfusion by ASL showed that CsA treatment significantly increased the rate of ‘normal’ perfusion in the non-AAR. Since an equivalent increase was not observed in IPC treated animals, it is unlikely that this corresponds to increased cardiac function in these animals. Although this remains an intriguing and unexplained effect of CsA, it did not influence the calculation of AAR by this method since the area of decreased perfusion was defined by a threshold approach based on this normal value. This study therefore suggests that ASL perfusion mapping may provide a valid method for AAR quantification even in the presence of cardioprotective interventions that increase myocardial perfusion. This should be investigated further in order to fully validate the use of this MR method for assessing myocardial salvage. In this study pixel-wise comparison between different CMR methods was not possible because of the differing cardiac phase used during imaging. Furthermore, slice-wise comparison with histological staining was not possible because of different slices thickness  and were conducted in accordance with the Animals (Scientific Procedures) Act 1986 published by the UK Home Office and the Guide for the Care and Use of Laboratory Animals published by the US National Institutes of Health 1996. B6/SV129 male mice were purchased from Harlan Laboratories, UK and were aged 10–14 weeks at the time of surgery. All laboratory reagents were purchased from Sigma, UK unless otherwise stated.in vivo experimentation was exactly carried out as previously described24. Briefly, Mice were anesthetized by inhalation of isoflurane  vaporized in oxygen (1.5–1.8% isoflurane in 1.5 L/minute oxygen). Body temperature was maintained at 36.5 ± 0.5 °C. Animals were artificially ventilated  and open-chest surgery performed to induce IRI. Myocardial ischemia was induced by ligation of the left anterior descending (LAD) coronary artery using an 8–0 non-absorbable polypropylene suture  and a custom-made snare system. Myocardial reperfusion was induced by release of the occluding snare. Short lengths of the ligating suture were left in situ for subsequent ex vivo histological staining to delineate the AAR by Evans blue staining.The established Mice were recovered and analgesia was provided by buprenorphine  0.1 mg/kg intramuscular administered 30 minutes prior to the completion of surgery and at 6 and 24 hours post-surgery.Mice were randomized to control or intervention groups for each study. Treatment protocols are summarized in Supp. Figure IPC study. control mice (n = 6) underwent 15 minutes stabilization, 30 minutes ischemia and 72 hours reperfusion  and CsA treated (n = 9) mice underwent 15 minutes stabilization, 30 minutes ischemia and 72 hours reperfusion . Real-time monitoring was performed of respiration , ECG  and body temperature . Body temperature was maintained at 36.5 ± 0.5 °C. CMR was undertaken using a 9.4 T horizontal bore scanner  fitted with 1000 mT/m gradient inserts  running VNMRJ software (version 2.3 A). Volume resonator quadrature radiofrequency (RF) coils  were used for RF transmission and signal reception.Respiration gating was achieved using respiratory bellows (described above) to trigger image acquisition immediately following exhalation. Cardiac gating was achieved by detection of the integrated ECG trace to allow triggering of image acquisition following detection of the ECG R-wave. Respiration and cardiac gating parameters are described for each CMR sequence protocol below.CMR image analysis was performed blinded and randomized using custom scripts . This consisted of myocardial segmentation, selection of normal region of interest (ROI) and threshold analysis, as described to follow.°, cine frames = 20, matrix size = 128 × 128, in-plane resolution = 200 µm, slice thickness = 1 mm, 10 short-axis slices). Endomycardial segmentation was performed using the freely available software Segment .Cine imaging was acquired in the short axis view using a stack of 10 slices to assess cardiac function  was administered via an intraperitoneal infusion line as a single bolus of 0.6 mmol/kg Gd-DTPA . Following a delay of 10 minutes to allow for enhancement by Gd within the area of infarction, a set of T1-weighted images was acquired. A Look-Locker-style gradient echo acquisition was used to determine the null point of healthy myocardium in one mid-ventricle slice  = 25.6 mm × 25.6 mm, slice thickness = 1 mm, flip angle = 10°, recovery delay = 1 s, acquisition time ~ 3 minutes). LGE images were acquired using the single inversion time point chosen with Look-Locker acquisition  .LGE CMR was conducted as described previously by Price 1-signal as a percentage of the total number of pixels.The area of infarction was determined using an automated delineation method constrained by the myocardial borders using Segment software . Infarct size was calculated as the number of pixels with gadolinium enhanced T2 mapping was performed using a cardiac and respiration gated spin-echo sequence, with sequence parameters as follows: TE =  ms, TR = RR-interval, matrix = 128 × 128, FOV = 25.6 mm × 25.6 mm, 7 short axis slices (one per cardiac cycle), slice thickness = 1 mm. A delay following the R-wave was introduced to ensure that the MR signal was measured at the same cardiac phase.T2-relaxation time were fit to the myocardial signal intensity on a pixel-wise basis for each slice using MATLAB scripts written in-house. Normal T2 map signal values were defined by selection of an ROI in the second from most basal slice, which is expected to be normal (corresponding to non-AAR) in this mouse model of IRI. Pixels with T2 values greater than 1 standard deviation above the ‘normal’ T2 were considered to have elevated T2 values26. The area of elevated T2-signal was calculated as a percentage of the total number of myocardial pixels .Exponential decay curves of T21. T1-relaxation was measured following slice-selective (control condition) and global (tagged condition) inversion RF pulses using a multi-slice segmented ECG-gated Look-Locker method. Scanning parameters were as follows: TE/TR(inv)/TR(RF) = 1.18 ms/13.5 s/3 ms, flip angle = 5°, FOV = 25.6 mm × 25.6 mm, matrix = 128 × 128, slice thickness = 1 mm, 6 slices total (3 slices/acquisition), number of points in recovery curve = 50. The inversion pulse was respiratory and cardiac gated, and the Look-Locker acquisition was only cardiac gated.Myocardial perfusion was quantified using a multi-slice flow alternating inversion recovery (FAIR) ASL sequence1-recovery curves following slice-selective and global inversion pulses, incorporating a blood pool input function (bpMBF quantification)19. This was performed on a pixel-by-pixel basis to generate ASL perfusion maps for each heart slice using MATLAB scripts written in-house. Normal perfusion values were defined for each heart by selection of a ROI in the second from most basal slice. Two thresholds were compared to assess perfusion deficit: pixels with perfusion values less than 1 standard deviation (1 SD) and 2 standard deviations (2 SD) below the ‘normal’ perfusion value for that heart. The area of reduced perfusion was calculated as a percentage of the total number of myocardial pixels  for each threshold.Multi-slice perfusion maps were calculated by comparison of T1 maps used for ASL perfusion quantification  were also analyzed for areas of increased T1 corresponding to edema. Again, normal T1 was defined by the ROI in the second from most basal slice and T1 values great than 1 standard deviation above normal were considered elevated T1.The Tex vivo histological staining using triphenyl-tetrazolium chloride (TTC) and Evans blue for determining MI size and AAR, respectively. Briefly, immediately following completion of CMR, mice were sacrificed by administration of ketamine 10 mg/ml , xylazine 2 mg/ml  and atropine 0.06 mg/ml  at 0.2 ml/10 g. Hearts were rapidly extracted and the aorta cannulated to allow retrograde perfusion. Residual blood was removed by perfusion of saline (pre-warmed to 37 °C). MI size was delineated by perfusion of TTC . The occluding ligature used to induce ischemia was securely re-occluded and Evans blue dye (1.5 ml 0.5% Evans blue in distilled water) perfused to delineate the AAR. Hearts were stored at −20 °C to facilitate manual slicing of 7 transverse slices of approximately 1 mm thickness from the apex to the base of the left ventricle. Myocardial slices were briefly incubated in 10% formalin at room temperature and imaged  in a custom-made acrylic block.In order to validate cardiac CMR measurements of infarct size and the AAR, hearts were subjected to Quantifications were performed on transverse slices of the left ventricle using ImageJ planimetry  and infarct size (IS) and AAR were expressed as a fraction of LV area (IS/LV% and AAR/LV%). Infarct size as fraction of AAR was also calculated (IS/AAR%).All statistical analysis was completed using GraphPad Prism® version 7.0 . Differences were considered significant where p < 0.05; p-values are provided alongside for statistical analysis.Percentage areas are reported for the left ventricle (LV) as mean ± standard deviation. Comparison of area quantifications between groups was by unpaired t-test where two groups were compared and by one-way ANOVA and Bonferroni test where more than two groups were compared. Comparison of area quantifications within groups was by paired t-tests. Bland-Altman plots were generated to compare histological and CMR parameters for individual animals. Biases from Bland-Altman analyses are reported.2 (ms) ASL perfusion (ml/g/min) and T1 (s) values were calculated for areas deemed ‘normal’ and ‘elevated’ or ‘reduced’ by threshold analysis. Mean values were compared for each study using one-way ANOVA and Bonferroni test where results are reported as multiplicity adjusted p-values.Mean TSupplementary information


T1-weighted variable-flip-angle 3D TSE has emerged as a promising intracranial vessel wall imaging technique. To increase spatial coverage and cerebrospinal fluid (CSF) attenuation, a whole-brain 0.5-mm-reoslution protocol based on an inversion-prepared 3D TSE sequence has recently been proposed at 3T. However, its 11-12-min scan time renders it clinically impractical. This work aimed to develop an expedited protocol and validate it on patients.Elliptical data sampling and prolonged echo train length (ETL) can be exploited to expedite the 3D TSE acquisition. However, this would reduce SNR and compromise vessel wall delineation. On the other hand, SNR is intimately related to the refocusing flip angles that are calculated for a prescribed signal evolution of a tissue with specific T1 and T2 values (denoted here as simulation T1 and T2). We hypothesized that an appropriate choice in the combination of ETL and simulation T2 may help achieve an efficient protocol.On a 3T system, the effects of simulation T2 and ETL on wall SNR, wall-CSF CNR, and white-gray matter CNR (indicative of T1 contrast weighting) were first explored on 9 healthy subjects. Simulation T2 varied  while ETL was held fixed at 36 (5 subjects) or 60 (3 subjects), and ETL varied  while simulation T2 was held fixed at 170 ms (1 subject). The range of potential protocols (i.e. combinations of ETL and simulation T2) was then narrowed. Specifically, ETL = 52 combined with a simulation T2 of 140, 170, and 200 ms were respectively tested on 7 healthy subjects. In addition, a combination of ETL = 36/T2 = 100 ms was used as a reference. An optimal imaging protocol was determined from the four scans and finally applied to a pilot study comprising 18 patients with various known arterial wall disease.Increasing simulation T2 boosted SNR and CNR Figure . As expeWhole-brain intracranial vessel wall evaluation at 3T is feasible within a clinically acceptable scan time - 8 min. A large-scale trial on using the technique for diagnosis of stroke etiology is underway to establish its clinical usefulness.