In vivo right ventricular diastolic pressure–volume relationships were measured in anesthetized animals; diastolic force–length relationships in single enzymatically dissociated myocytes and myocardial creatine kinase levels by Western blot. We observed diastolic dysfunction in right ventricular failure indicated by significantly steeper diastolic pressure–volume relationships in vivo and diastolic force–length relationships in single myocytes. There was a significant reduction in creatine kinase protein expression in failing right ventricle. Dysfunction also manifested as a shorter diastolic sarcomere length in failing myocytes. This was associated with a Ca2 +-independent mechanism that was sensitive to cross-bridge cycling inhibition. In saponin-skinned failing myocytes, addition of exogenous creatine kinase significantly lengthened sarcomeres, while in intact healthy myocytes, inhibition of creatine kinase significantly shortened sarcomeres. Creatine kinase inhibition also changed the relatively flat contraction amplitude–stimulation frequency relationship of healthy myocytes into a steeply negative, failing phenotype. Decreased creatine kinase expression leads to diastolic dysfunction. We propose that this is via local reduction in ATP:ADP ratio and thus to Ca2 +-independent force production and diastolic sarcomere shortening. Creatine kinase inhibition also mimics a definitive characteristic of heart failure, the inability to respond to increased demand. Novel therapies for pulmonary artery hypertension are needed. Our data suggest that cardiac energetics would be a potential ventricular therapeutic target.Our objective was to investigate the role of creatine kinase in the contractile dysfunction of right ventricular failure caused by pulmonary artery hypertension. Pulmonary artery hypertension and right ventricular failure were induced in rats by monocrotaline and compared to saline-injected control animals.  •Rats with pulmonary artery hypertension had right heart diastolic dysfunction.•Failing myocytes had decreased levels of creatine kinase protein•In failing myocytes exogenous creatine kinase reversed dysfunction.•In healthy myocytes inhibition of creatine kinase mimicked dysfunction.•Decreased creatine kinase is linked to dysfunction in pulmonary artery hypertension. It has been demonstrated, in humans with left ventricular (LV) hypertrophy, that total CK activity is decreased The role of metabolic dysfunction in right ventricular (RV) failure caused by pulmonary artery hypertension (PAH) is less well studied than in left ventricular (LV) failure. Treatment of PAH is focused on the pulmonary vasculature, however, hypertension increases afterload on the RV and results in RV hypertrophy and failure. Right heart failure is the most common cause of death in patients with PAH 2For detailed methods see Supplementary data.2.1e.g.Male Wistar rats (200 g) received a single intraperitoneal injection of 60 mg/kg MCT to induce RV failure (FAIL) or an equivalent volume of saline as control (CON). Rats were killed upon showing external clinical signs of heart failure as previously reported e.g.. These w2.2In vivo hemodynamic measurements were made in mechanically ventilated rats, anesthetized with 1.5% isoflurane mixed with O2. The chest was opened and a Millar conductance catheter passed through the RV free wall into the RV cavity to simultaneously measure pressure and volume. Pressure–volume (PV) loops were recorded and the slope of the end-diastolic pressure–volume relationship (EDPVR) measured by occlusion of the ascending vena cava. In isolated hearts, collagen was assessed by picrosirius red staining of 10 μm thick cryosections cut through the ventricular short axis. Staining was measured by a blinded researcher using ImageJ .2.32 + ([Ca2 +]i) monitored using the ratiometric Ca2 + dye fura-2-AM  as previously described via external platinum electrodes at the desired frequency. Unless otherwise stated, experiments were carried out at 37 °C. The method of Hongo et al. 2 + sensitivity in intact myocytes.Single myocytes were isolated and intracellular Ca2 + buffer BAPTA-AM (100 μM) or BAPTA-AM plus the myosin ATP-ase and cross-bridge cycling inhibitor 2,3-butanedione monoxime . To inhibit all forms of CK, the irreversible agent 2, 4-dinitro-1-fluorobenzene  was added for 10 min. To test the role of CK in controlling resting SL, myocytes were permeabiliized with saponin (0.01 mg/ml) in an intracellular-like solution. Cells were incubated in this solution with or without exogenous muscle isoform CK-(MM) from bovine heart muscle (Sigma) at a concentration of 4.4 mg/ml  for 30 min before SL was measured at 20–23 °C.To investigate the control of resting SL, Tyrode solution was modified by inclusion of the intracellular Cain vivo EDPVR, was measured Mechanical manipulation of myocytes was performed with a MyoStretcher . Myocytes were attached to stiff glass fibers using MyoTak™ glue (IonOptix) 2.4Muscle CK protein (CK-M) levels from RV and LV tissue isolated from CON and FAIL animals were assessed by bicinchoninic acid assay and Western blotting with primary antibodies for CK-M ((MM-2) sc-69848, 1:500, Santa Cruz Biotech and anti-GAPDH, G9545, 1:100,000, Sigma). For mitochondrial-CK (CK-mito). the primary antibody was (sMt CK (c-18): sc15168 at 1:200 dilution, Santa Cruz) and secondary antibody Donkey anti-Goat HRP (Stratech 705-035-147) at 1:5000 dilution. Brain-CK (CK-B) was assessed with (CK-B (G-6): sc-374072 antibody, Santa Cruz). GAPDH was used as a loading control for protein normalization. Signals were quantified using Aida Image Analyzer (v4.22) and normalized to GAPDH.2.5Results are presented as mean ± SEM. P < 0.05 was considered significant. Unpaired t-tests, one-way or two-way repeated measures ANOVA with multiple testing corrections were used as appropriate. Numbers of rats, hearts and myocytes used in each experiment are given in the relevant table and figure legends.33.1Consistent with previous reports, there was a significant increase in the heart: body weight and lung: body weight ratio in FAIL animals. The increase in heart weight was principally due to a significant increase in the RV: LV weight, indicating RV hypertrophy .In vivo measurement of RV pressure and volume showed a significant increase in systolic pressure (see Suppl. Table 1). PV loops (PV loops A were usPV loops B suggestPV loops .3.2in vivo EDPVR) was significantly increased in RV FAIL myocytes , resting force normalized to XSA and % length change was still significantly greater in FAIL myocytes  indicating that larger XSA was not the sole cause of the steeper EDFLR in FAIL myocytes.The source of dysfunction might therefore originate within the myocytes. Indeed when single cardiac myocytes were attached to glass fibers and stretched A, B the myocytes C. For co2 +]i  SL increased and increased further upon additional exposure to the myosin ATP-ase inhibitor BDM (40 mM)  were compared to the Ca2 +-independent change in SL . The Ca2 +-independent change in SL was significantly greater in FAIL myocytes compared to both the Ca2 +-independent change in SL in CON and to the Ca2 +-dependent change in SL in FAIL (To investigate a possible Ca (40 mM) A. The Ca in FAIL B.3.4Expression of CK-M was significantly reduced in RV FAIL A but notIn the presence of 10 mM phosphocreatine, SL was significantly shorter in skinned RV FAIL myocytes than RV CON (as seen in intact cells). Exposure to 4.4 mg/ml exogenous CK caused no change in SL in CON cells but significantly increased SL in RV FAIL cells such that their SL was no longer significantly shorter than CON cells D. This eWhen intact cells were exposed to the CK inhibitor DNFB (20 μM) there was a significant shortening of SL in all cells A howeverA systolic characteristic of RV FAIL cells is a steeply negative contraction–stimulation frequency relationship compared to CON cells 44.1e.g.in vivo systolic dysfunction may become apparent.The increase in end systolic pressure in MCT-treated animals is evidence of PAH. The designation of our MCT-treated animals as heart failure is based on the appearance of previously validated external clinical signs 4.2Reduction of CK activity has been described in human diseased myocardium in vivo EDPVR in failing hearts but do not attribute this to increased fibrosis. At a similar stage of disease other MCT studies have not observed increase in fibrosis Previous work has shown that diastolic function was preserved in MCT-induced hypertrophy prior to failure  Investigation of the diastolic force-length relationship in single myocytes is a useful approach to isolate intracellular mechanisms from the influence of the extracellular matrix 4.32 +]i and myofilament Ca2 + sensitivity, however we saw no evidence of an increase in either of these parameters in failing myocytes. We do provide evidence that the reduction in diastolic SL in failing cells occurred predominantly through a Ca2 +-independent (BDM-sensitive) rather than a Ca2 +-dependent (BAPTA-sensitive) mechanism. Importantly, we show that reduced diastolic SL was improved by addition of exogenous CK in the presence of PCr, suggesting a requirement for functional CK rather than just its physical presence, and mimicked in healthy cells by pharmacological inhibition of CK. Regulation of SL or passive tension by increased ADP is well-documented 2 +-independent force production We observed significant reduction of the 2 major CK isoforms (CK-M and CK-mito) in RV FAIL hearts. Commonly described regulators of diastolic SL are diastolic [CaThe steeper contraction–frequency relationship in RV FAIL myocytes is a cellular manifestation of the inability of failing hearts to respond to increased demand (the characteristic that underpins the NYHA classification of heart failure). The observation that inhibition of CK in CON myocytes mimics the contraction-frequency relationship of RV FAIL myocytes supports a central role of metabolic dysfunction in this key characteristic of heart failure −/−, mitochondrial CK−/−−/−−/−−/− mice were reported to have smaller hearts and lower pressures Interestingly single isoform . Travel grants to EDF from the Physiological Society and the Boehringer Ingelheim Fonds.University of Leeds PhD scholarship to EDF; Emma and Leslie Reid PhD scholarship to DB; MH is an employee of IonOptix LLC.


Theoretically, the byproducts of blood breakdown observed with IMH lead to decreased T1 and T2 (T2*). [1 and T2. [2-weighted spin-echo), undesired signal loss from T2* (weighted) images or the uncertainty introduced by contrast agent kinetics. Hypothesis: Combined T1 and T2 mapping can characterize reperfused MI without contrast agents.Reperfusion injury in acute myocardial infarction (MI) results in edema, necrosis, microvascular obstruction (MVO), and intramyocardial hemorrhage (IMH), the latter presents an interesting clinical target.  Cardiova2-mapping [1-mapping (MOLLI) [2W TSE (BB-T2-STIR) [2W images/T1/T2 maps as areas of hypointensity surrounded by hyperintense signal/T1/T2 representing edema. MVO was defined in EGE images as hypointense areas surrounded by enhanced MI. The co-localization of tissue types among techniques was examined.MI was induced in swine by 1 N=3) or 2 (N=3) hr balloon occlusion of the LAD after the first diagonal, with MRI 7-9 days post MI . Relaxometry: 3D respiratory navigator-gated T or 2 (N= (MOLLI) . ClinicaT2-STIR) ; early (T2-STIR) . IMH was1 and T2, and was spatially consistent with the hypoenhanced core in BB-T2-STIR and with MVO in EGE. Edema was observed in all animals (elevated T1and T2). , while within IMH T1 was lower (p = 0.001) and T2 the same (p = 0.28). (Fig. Planimetry showed that relative to remote myocardium, T1 or T2 can be used to separate tissues, combined T1 and T2 mapping may allow for more accurate detection of IMH in reperfusion injury, without variability from contrast kinetics, or BB-T2-STIR artifacts. [2 was superior in edema detection, while T1 performed better in IMH detection. Combined relaxometry may identify tissues with better specificity than individual and may help clarify the link between MVO and IMH. High-resolution relaxometry may be necessary to avoid partial volume.Though either Ttifacts.  Based onFunded in part by the American Heart Association - 11SDG5280025.


Adenosine stress magnetic resonance is highly accurate for the detection of myocardial perfusion abnormalities. Visual assessment of inducible wall motion abnormalities (IWMA) during adenosine has low sensitivity but high specificity since only high-grade perfusion defects are associated with detectable IWMAs. The novel technique Feature Tracking (FT) measures myocardial strain and gives detailed information about regional myocardial deformation. The aim of this study was to investigate FT for the detection of myocardial ischemia during adenosine stress.A total of 62 patients with suspected or known coronary artery disease (CAD) underwent adenosine stress CMR at 1.5 or 3T. Patients with evidence of myocardial scar iby late gadolinium enhancement (LGE), WMA at rest and impaired left ventricular function (LVEF) were excluded (n = 34). Short axis (SAX) cine views were acquired before and after 3 minutes of continuous adenosine infusion (0.14 mg/min/kg). Patients with abnormal stress perfusion were considered positive for myocardial ischemia (n = 15) and segments with perfusion defects were defined as ischemic (n = 61). Patients without perfusion defects and without known CAD were defined as normal and served as control . TomTec 2D Cardiac Performance Analysis software was used to derive quantitative assessment of circumferential strain (CS) and strain rate (SR) from the three SAX cine views at rest and under stress.There was no significant difference of CS at rest between normal and ischemic segments . Normal segments demonstrated a significant increase during stress for CS  as well as for SR . In ischemic segments no significant difference was observed for CS between rest and stress (-28.8 ± 9.6% vs. 31.9 ± 12.8%, p = 0.064; Figure Strain analysis with FT during adenosine stress demonstrated significant differences between normal and ischemic segments. Therefore it may be a valuable additional tool for the assessment of myocardial ischemia.No funding.


Several clinical trials and recent meta-analyses have demonstrated that administration of recombinant human granulocyte-colony stimulating factor (G-CSF) is safe and, only in patients with large acute myocardial infarction (AMI), is associated with an improvement in left ventricular ejection fraction. Moreover, the mobilization and engraftment of the bone marrow-derived cells may differ significantly among patients, interfering with the restoration of left ventricular function after treatment. Therefore, the clinical potential application of the G-CSF has not yet been fully elucidated.The RIGENERA 2.0 trial is a multicenter, phase II, placebo-controlled, randomized, open-label, with blinded evaluation of endpoints (PROBE) trial in which 120 patients with an acute ST-elevation myocardial infarction (STEMI) undergoing successful revascularization but with residual myocardial dysfunction will be enrolled. In cases where there is a left ventricular ejection fraction (LVEF) ≤45 % the patient will be electronically randomized (1:1 ratio) to receive either subcutaneous recombinant human G-CSF (group 1) or placebo (group 2) both added on top of optimal standard of care. Both groups will undergo myocardial contrast echocardiography with intravenous infusion of sulfur hexafluoride (MCE) whilst undergoing the echocardiogram.The primary efficacy endpoint is the evaluation of the LVEF at 6 months after AMI assessed by cardiac magnetic resonance. Secondary efficacy endpoints are the evaluation of LVEF at 6 months after AMI assessed by echocardiography, left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume (LVESV) assessed by cardiac magnetic resonance and echocardiography at 6 months, together with the incidence of major adverse clinical events (MACE) defined as death, myocardial infarction, sustained cardiac arrhythmias, cardiogenic shock, stroke and re-hospitalization due to heart failure at 1 year.The RIGENERA 2.0 trial will test whether G-CSF administration and MCE, through the enhancement of the bone marrow-derived cells homing in the myocardium, determines an improvement in regional and global contractile function, myocardial perfusion and infarct extension in patients with large AMI. The results of the present study are expected to envision routine clinical use of this safe, affordable and reproducible approach in patients with successful revascularization after AMI.NCT02502747 (29 June 2015); EudraCT: 2015-002189-21 (10 July 2015).ClinicalTrials.gov: The online version of this article (doi:10.1186/s13063-016-1172-0) contains supplementary material, which is available to authorized users. The long-term prognosis of patients suffering from acute myocardial infarction (AMI) has progressively improved since the introduction of reperfusion therapies and, in particular, of primary angioplasty . In the A major reason for the high morbidity and mortality is that the heart has an inadequate regenerative response to the myocardial necrosis following AMI; cell death from the ischemic damage can lead to progressive ventricular dilation and dysfunction . Numerous pre-clinical studies and small to intermediate size clinical trials have demonstrated beneficial effects of bone marrow-derived cells on top of state-of-the-art reperfusion treatment providing compelling evidence that bone marrow- derived cells do contribute to cardiac repair after acute myocardial injury, limiting infarct expansion and improving cardiac function, most likely via paracrine mechanisms –7.Considering that recovery of post-infarction left ventricular function is favorably correlated with bone marrow-derived stem cell mobilization induced by endogenous granulocyte-colony stimulating factor (G-CSF) , 9, therHowever, the clinical effects of G-CSF on patients with AMI have so far shown mixed results : G-CSF wp < 0.005) (unpublished data).In our study population, the long-term (10 years) follow-up data, recently collected, confirmed the safety of the protocol and, remarkably, patients treated with G-CSF showed a significant improvement of the quality of life assessed by New York Heart Association (NYHA) functional class, Seattle Heart Failure Model, Minnesota Living with Heart Failure Questionnaire  was designed to specifically test the efficacy of the combined effect of subcutaneous G-CSF and sulfur hexafluoride on post-infarction left ventricular function in patients with STEMI.The overall objectives of the RIGENERA 2.0 trial are to determine whether, in patients with large AMI undergoing primary or rescue angioplasty, the administration of subcutaneous Lenograstim  associated with myocardial contrast echocardiography and the intravenous infusion of sulfur hexafluoride  determines an improvement in regional and global contractile function, myocardial perfusion and infarct size and is associated to a better quality of life.LVEF at 6 months assessed by cardiac magnetic resonance and centrally reviewed.Specifically, the primary efficacy endpoint is:Left ventricular end-diastolic volume (LVEDV) assessed by cardiac magnetic resonance at 6 months and centrally reviewedLeft ventricular end-systolic volume (LVESV) assessed by cardiac magnetic resonance at 6 months and centrally reviewedLeft ventricular ejection fraction (LVEF) assessed by 2D echocardiography at 6 months and centrally reviewedLeft ventricular end-diastolic volume (LVEDV) assessed by 2D echocardiography at 6 months and centrally reviewedLeft ventricular end-systolic volume (LVESV) assessed by 2D echocardiography at 6 months and centrally reviewedIncidence of major adverse clinical events   trial. One hundred and twenty STEMI patients are planned to be enrolled in four Italian centers . Patients with an acute STEMI, as defined by the universal definition of AMI, undergoing acute revascularization  within 24 hours of symptom onset or thrombolysis within 12 hours followed by acute PCI within 24 hours of symptom onset) will be screened at investigational sites. Patients who have had acute PCI in institutions different from the investigational sites (recruiting centers) can also be included: interested patients may be referred for screening to any of the participating study sites within 3 to 4 days. Every patient will be informed in person and receive the patient information letter and informed consent form; as this trial has not yet begun the recruitment phase, no informed consent form has been provided to any patient; however, informed consent will be obtained from all participants.The study was approved by the ethical committee  and AIFA  in July 2015. The trial will be conducted in accordance with the Italian Medical Drug Law  and the Good Clinical Practice guidelines. The RIGENERA 2.0 trial is an investigator-initiated trial and funded by the Italian Ministry of Education and Research (PRIN 2010/2011/2010S7CET4).Informed consent and assessment of eligibility of patients with respect to inclusion and exclusion criteria will be done at the recruiting centers.Signed and dated informed consentMen and women of any ethnic origin aged 18 years or olderPatients with acute STEMI as defined by the universal definition of AMISuccessful acute reperfusion therapy  flow ≥2) within 24 hours of symptom onset or thrombolysis within 12 hours of symptom onset followed by successful PCI within 24 hours after thrombolysisLVEF ≤45 % with significant regional wall motion abnormality assessed by quantitative echocardiography 3 to 6 days after reperfusion therapyInclusion criteria are:Participation in another clinical trial within 30 days prior to randomizationPregnant or nursing women or women in childbearing age not able to exclude the possibility of a pregnancyMental condition rendering the patient unable to understand the nature, scope and possible consequences of the study or to follow the protocolNecessity to revascularize additional vessels, outside the target coronary artery, after investigational therapy/placebo administration Persistent cardiogenic shockKnown hematological and neoplastic diseasesSevere impaired renal function, i.e., eGFR <30 ml/min.Persistent fever or diarrhea not responsive to treatment within 4 weeks prior to screening or severe infectionUncontrolled hypertension (systolic >180 mmHg and diastolic >120 mmHg). Life expectancy of less than 2 years from any non-cardiac cause or neoplastic diseaseExclusion criteria are:After ensuring that a patient meets all other eligibility criteria, the investigators will perform the echocardiography, an electronic record of which will be kept and transferred to the central Echocardiography Core Laboratory following analysis. After local quantification of LVEF, randomization will be allowed for all patients with LVEF ≤45 %. As soon as possible after the enrollment the first cardiac magnetic resonance will be performed. At randomization, every patient will receive a number that will be used as the key identifier for the entire study period.Group 1: placebo on top of optimal standard of care   5 to 10 days after successful reperfusion of the culprit vessel of a large AMI, on top of optimal standard of care  , blood pressure, blood count and coagulation analyses will be monitored  the dose of G-CSF in 24 hours will be halved, and in the case of leukocytosis  completely stopped.After hospital discharge, all study patients will return to the clinical center for a follow-up visit after 30 days. Six months after randomization all the patients will undergo outpatient cardiac magnetic resonance and conventional echocardiography. At 1 year all patients will attend a final site visit at the clinical centers collecting any clinical event. However, all clinical endpoints will be reported as occurring throughout the follow-up. Major adverse cardio-cerebrovascular events  at 1 year will be adjudicated by a clinical event committee blinded to the patient treatment allocation. This will ensure a consistent and unbiased adjudication of events across all investigational sites.In the patients enrolled in the study, two different contrast-cardiac magnetic resonance examinations will be performed: the first as soon as possible after the enrollment, the second 6 months after the randomization. Moreover, the patients with severe renal disease will be excluded (glomerular filtration rate <30 ml/min). Cardiac magnetic resonance will be performed on a 1.5-T clinical scanner  using a phased-array cardiac receiver coil. Additionally, ECG-gated breath-hold cine imaging will be performed.Morphological and cine evaluation: to determine left ventricular function, using a segmented steady-state free-precession pulse sequence (TrueFISP) in multiple short-axis views every 8 mm by encompassing the left ventricle from base to apex. Typical in-plane resolution is 1.7 × 1.2 × 8 mm; slice thickness: 6 mm; gap: 2 mm. Long-axis view, comparable with standard echo images  will be acquiredMyocardial edema evaluation: presence and location of myocardial edema, including intramyocardial hemorrhage will be evaluated on T2-weighted images short-TI inversion-recovery fast spin echo pulse, on consecutive short-axis views. The typical parameters are reported: FOV: 380 to 400 mm; TR: 2 R-R intervals; TE: 100 ms; TI: 150 ms; matrix: 256 × 192; slice thickness: 8 mmPerfusion at rest evaluation: rest first-pass myocardial perfusion will be performed during administration of a gadolinium-based contrast agent  using single-shot saturation recovery gradient-echo pulse sequence, turbo-FLASH sequences. Three short-axis slices will be obtained per heartbeat, every 10 mm, covering the infarct area as seen during cine imaging Early enhancement evaluation: after gadolinium injection, the presence of microvascular damage will be evaluated by T1-weighted 3D inversion recovery gradient-echo sequences. The typical parameters are reported: TR: 4.5 ms; TE: 1.3 ms; flip angle: 158°; slice thickness: 8 mm; gap: 2 mm; matrix: 128 × 256; field of view: 350 mm; pixel size: 1.4 mm/1.4 mm. The images will be acquired on the same slice position used for cine images. The presence of an “early enhancement” will be performed after 2–5 minutes after contrast injectionDelayed enhancement evaluation: the presence of myocardial necrosis detected by delayed contrast deposition (“late gadolinium enhancement”) will be evaluated with the same sequences on point 4, but acquired 10–15 minutes after contrast injection. The inversion time will be individually adapted to suppress the remote myocardium signal The cardiac magnetic resonance protocol includes:Analysis of steady-state free-precision sequences: on all short-axis cine slices, the endocardial and epicardial borders will be outlined manually on end-diastolic and end-systolic images. LVEF, end-diastolic and end-systolic volumes, and left ventricular mass will be calculated from the short-axis viewsAnalysis of T2-weighted sequences: on T2-weighted images, infarct-related edema was considered present when the signal intensity of the myocardium was >2 standard deviations of the mean signal intensity of the controlateral remote region. The total amount of myocardial edema, representing area at risk, will be expressed as grams and as percentage related to total myocardial massEvaluation of Turbo-FLASH sequences: perfusion defects on “first pass” will be evaluated for each segment according with the 17-segments modelDelayed enhancement analysis: on delayed enhancement imaging, myocardial infarction will be considered present if the signal intensity of hyperenhanced myocardium is >5 standard deviations of the mean signal intensity of the remote region, and microvascular damage will be defined as a hypoenhanced region within infarcted myocardium. The total amount of myocardial necrosis will be expressed as grams and also as percentage related to total myocardial mass. Moreover, a score will be used to define the extent of necrosis for each segment according with 17-segments model: 1 = necrosis between 0 and 25 % of the entire segment; 2 = necrosis between 25 % and 50 % of the entire segment; 3 = necrosis between 50 % and 75 % of the entire segment; 4 = transmural necrosis extending > 75 % of the entire segment. Finally the amount of salvaged myocardium, expressed as the difference between area at risk on T2-weighted images and extent of delayed enhancement, will be defined.After acquisition protocol, the images will be analyzed off-line using a dedicated workstation with a dedicated post-processing software (Circle cvi42). The following parameters will be obtained for each of two CMR acquisitions:The echocardiographic evaluation will be performed in accordance with the recommendations of the American Society of Echocardiography. The following views should be evaluated during each echo evaluation: parasternal short-axis view, parasternal long-axis view, apical four-chamber view, apical two-chamber view, apical three-chamber view. Quantitative analyses include measurements of left ventricular dimensions: left ventricle end-diastolic/end systolic diameter, LVEDV, LVESD and LVEF, obtained according to Simpson’s rule.Myocardial contrast echocardiography will be performed in both groups immediately before the first dose of Lenograstim or placebo and on the morning of the last day of treatment. Myocardial contrast echocardiography will be carried out by using a new generation echo machine , equipped with a 3.5-MHz ultrasound probe and contrast pulse sequencing, which is a software for acquisition and analysis of contrast signal. Analysis of contrast signal relies on a continuous emission of ultrasound and a contemporary comparison between fundamental harmonics deriving from tissues and second harmonics reflected by microbubbles. When using this kind of imaging modality, the image will normally be totally dark prior to contrast administration, as the signal coming from the tissues is nullified and suppressed, whereas the microbubbles’ signal is amplified. A second generation ultrasound contrast agent SonoVue®  will be administered, according to the market authorization, by peripheral venous access and continuously injected by a dedicated infusion pump . Continuous infusion provides a constant bubble signal that is fundamental to assess myocardial perfusion. After the destruction of microbubbles by a high mechanical index pulse, myocardial perfusion will be visually assessed during their replenishment of the coronary circulation Images will be acquired as follows: real-time and triggered apical four-chamber view, real-time and triggered apical two-chamber view, real-time and triggered apical three-chamber view, real-time and triggered parasternal short-axis view.Each enrolled patient will remain in the study throughout the entire study duration, with a minimum follow-up of 1 year for each patient. A study patient’s participation may be terminated early for reasonable cause, such as the investigator’s medical decision. At any time the patient has the right to withdraw consent without a negative impact on their medical treatment. However, the investigators are encouraged to ask for the patient’s permission for further follow-up telephone contacts from those whose decision for discontinuation was based on the need for further outpatient visits. Patients will be enrolled during a recruitment phase of approximately 2 years. Since minimum study duration for one patient is 1 year, the overall study duration is approximately 3 years. The Data Monitoring Committee may terminate the study earlier based on safety concerns at any time, or based on the interim efficacy analysis. Competent authorities/ethics committees retain the right of premature termination of the study according to applicable regulations. At an individual study center, the study may be terminated early if the work performed is not compliant with Good Clinical Practice guidelines.The sample size was calculated on the basis of our previous experience, assuming a difference in LVEF of 5 % between the group treated with G-CSF and controls and a standard deviation of 7 %. In addition, considering the novelty of the study one interim analysis will be performed after the enrollment of 60 patients to check presence of a favorable effect of G-CSF + MCE on left ventricular function in comparison to placebo + MCE. Early termination will be possible at this stage if the experimental group show no increase in LVEF fraction in comparison to the control group. However, all patients recruited must complete a 1-year follow-up, even if the trial is stopped prematurely.t test, or a Wilcoxon rank-sum test if data show serious deviations from a normal distribution. Categorical data will be compared using a chi-square test or Fisher’s exact test, as appropriate. Ordinal data will be compared using a chi-square test for trend.All collected data will be summarized by treatment group. Continuous data will be reported by the number of available data points, mean, standard deviation, median and interquartile range. Categorical and ordinal data will be summarized by observed frequencies and percentages relative to the number of non-missing data. For continuous data, comparisons between treatment groups will be done using a two-sample p value is lower than 0.05.The primary endpoint of all-cause mortality will be the change in LVEF evaluated by cardiac magnetic resonance. Statistical significance will be claimed when the resulting Adverse events, related adverse events and severe adverse events will be summarized by body system and preferred term for the two treatment groups.In the last two decades, several clinical trials have investigated the effects of G-CSF therapy on cardiac repair: the results collected so far, however, indicate that G-CSF therapy is safe and may be associated with beneficial effects in patients with large AMI. However, the limited amount of evidence is inadequate to reach any definitive conclusions regarding the efficacy of G-CSF therapy.Therefore, larger randomized clinical trials, with appropriate power calculations, are needed in order to address the current uncertainties regarding this experimental therapeutic approach.The RIGENERA 2.0 trial, presented here, will test the combined efficacy of G-CSF administration and MCE in improving the regional and global left ventricular contractile function and reducing infarct extension in patients with large AMI, through the homing enhancement of the bone marrow-derived cells within the myocardium. The results of the present study are expected to envision the routine clinical use of this safe, affordable and reproducible approach in AMI patients with left ventricular dysfunction after successful revascularization.The RIGENERA 2.0 trial received ethical committee approval  and AIFA  approval in July 2015 and has not yet begun patient recruitment.


The purpose of this work is to analyze differences in left ventricular torsion between volunteers and patients with non-ischemic cardiomyopathy based on tissue phase mapping (TPM) cardiovascular magnetic resonance (CMR).TPM was performed on 27 patients with non-ischemic cardiomyopathy and 14 normal volunteers. Patients underwent a standard CMR including late gadolinium enhancement (LGE) for the assessment of myocardial scar and ECG-gated cine CMR for global cardiac function. TPM was acquired in short-axis orientation at base, mid, and apex for all subjects. After evaluation by experienced observers, the patients were divided in subgroups according to the presence or absence of LGE (LGE+/LGE-), local wall motion abnormalities (WM+/WM-), and having a preserved (≥50 %) or reduced (<50 %) ejection fraction (EF+/EF-). TPM data was semi-automatically segmented and global LV torsion was computed for each cardiac time frame for endocardial and epicardial layers, and for the entire myocardium.p = 0.018), but also for patients with wall motion abnormalities . Global myocardial torsion showed a positive correlation  with EF. Moreover, endocardial torsion was significantly higher than epicardial torsion for EF+ subjects  and for volunteers . The difference in maximum torsion between endo- and epicardial layers was positively correlated with EF  and age  for all subjects.Maximum myocardial torsion was significantly lower for patients with reduced EF compared to controls (0.21 ± 0.15°/mm vs. 0.36 ± 0.11°/mm, TPM can be used to detect significant differences in LV torsion in patients with reduced EF and in the presence of local wall motion abnormalities. We were able to quantify torsion differences between the endocardium and epicardium, which vary between patient subgroups and are correlated to age and EF. Left ventricle (LV) torsion, the counter-rotation of basal versus apical regions, is known to play a crucial role in cardiac contraction and relaxation , 2. The Previous studies have attempted to quantify myocardial torsion using tissue Doppler imaging , or specPrevious studies have shown the potential of TPM to detect disturbed regional myocardial motion in patients with hypertrophy , cardiomMyocardial twist has also been previously studied using local shear, mainly based on tagged CMR . The locWe present a method to quantify the myocardial and transmural  torsion using TPM imaging followed by a semi-automatic processing pipeline in a study cohort of 27 patients with non-ischemic cardiomyopathy and 14 normal controls. Our goal was to test the hypothesis that TPM can by employed to detect significant differences in LV torsion in patients with reduced ejection fraction (EF) and wall motion abnormalities (WM) compared to patients with preserved EF and control subjects.n = 10 subjects with restrictive cardiomyopathy, n = 9 subjects with dilated cardiomyopathy, n = 3 subjects with hypertrophic cardiomyopathy, n = 3 subjects with inflammatory cardiomyopathy, and n = 2 subjects with non-classified cardiomyopathy. All study subjects were included in accordance with the Institutional Review Board (IRB) of Northwestern University protocol, which permitted retrospective chart review in patients. Volunteers were recruited under an IRB approved prospective protocol and informed consent was obtained from all participants.The study cohort included 27 patients  with non-ischemic cardiomyopathy (NICM) in normal sinus rhythm and 14 healthy control subjects , as described in Table net = 3.6 was employed, which permitted data acquisition during breath-holding. The breath-hold time was 25 heart beats per slice. In all control subjects, a repeat CMR exam (rescan) including TPM was performed two weeks later to assess scan-rescan reproducibility of TPM parameters.All patients underwent standard-of-care CMR using 1.5 T MR systems . The examination included late gadolinium enhancement (LGE) for the assessment of myocardial scar as well as ECG gated time-resolved (cine) CMR for the evaluation of global cardiac function. In addition, patients underwent 2D TPM at basal, mid-ventricular (mid), and apical locations. TPM consisted of a black-blood prepared cine phase-contrast sequence with three-directional velocity encoding of myocardial motion . Spatio-temporal imaging acceleration (k-t GRAPPA) with a net acceleration factor of RLGE and cardiac cine CMR were qualitatively evaluated by an experienced observer based on the AHA 16-segment model . LGE anax,vy,vy) over the temporal series. Pixels with SD(vx) < 5 mm/s, SD(vy) < 5 mm/s and SD(vz) < 5 mm/s were considered stationary. A linear fit was performed for each velocity component of the resulting stationary tissue, which was subtracted from the velocity field. To reduce the noise level, a low-pass 3x3 SD filter was applied.TPM data were analyzed using a customized software solution built using the MevisLab platform . Pre-proSemi-automatic myocardium segmentation was subsequently performed. Two manual epi- and endocardial contours were drawn for each slice in one time point in the middle of the cardiac temporal sequence during systole. The manual contours initialized an active contour model, using the in-plane projected velocity field as guiding forces Fig. -a. The cIn order to distinguish between endocardial and epicardial regions, the centerline of the myocardial mask was automatically extracted using a skeletonization approach based on topology-preserving morphological thinning by Selle et al. . The voxx,vy,vz) were transformed into a cylindrical coordinate system  where the base of the cylinder was parallel to the short-axis slice and the center was at the center of the myocardium mask. The resulting velocity components were thus radial vr (positive-contraction/negative-expansion), long-axis vz (positive-shortening/negative-lengthening), and rotational vϕ (positive-clockwise/negative-anticlockwise) as previously described in [To remove translational motion of the whole heart from the velocity fields, a correction based on subtraction of global translation velocities in X and Y directions from the local velocity components was performed based on a previously reported strategy . The thrribed in .R for every time point, in order to obtain the angular velocity:The average rotational velocity of each myocardial slice was divided by the average myocardium radius θt was computed by integrating the angular velocity over time for the base, mid, and apical slices. The myocardial torsion T between base and apex at time t during the cardiac cycle was defined as their relative rotation angle Δθt normalized by the distance h between the respective slices:h is assumed to be fixed, i.e. the long axis shortening of the LV was not taken into account. Out assumption is based on the fact that the position of the basal and apical imaging planes remains static during acquisition. In general, using Eq. As shown in Fig. Tmax during the cardiac cycle was quantified. We assumed that the maximum of the torsion curve for the global myocardium, as well as for epi- and endocardial regions would be reached during end-systole. Absolute and relative difference in magnitude between maximum endocardial and epicardial torsion were also calculated:Torsion was computed for the whole myocardium, as well as for the endocardial and epicardial regions, respectively. In addition, maximum torsion for the entire myocardium To compare the temporal evolution of LV torsion over time for different groups, torsion-time curves for volunteers and patients with reduced and preserved EF were resampled at 5 ms time steps and then averaged.To assess inter-observer variability, TPM torsion analysis was performed by two independent observers, blinded to all subject information. The reproducibility of the entire analysis was tested on the 14 volunteers, who were scanned a second time. The semi-automatic segmentation was performed by the same observer.p < 0.05 was considered significant. Inter-observer variability and scan-rescan reproducibility were analyzed using Bland-Altman plots and by calculating mean differences and limits of agreement (mean ± 1.96xSD of the differences).All continuous parameters are reported as mean ± standard deviation. Differences in parameters between subject groups were assessed using the standardized t-test  for normal distributions and Wilcoxon rank sum test otherwise . We compTPM data from all subjects was successfully processed with our method. The processing time per subject was 10–20 min, depending on heart rate and thus number of time cardiac frames.Our study cohort consisting of 27 patients and 14 volunteers is described in more detail in Table Tmax for the patients with reduced EF (EF-) compared to the EF+ group  and compared to the control group . Also, Tmaxwas significantly reduced for the group WM+ compared to WM- and the controls , as shown in Fig. Tmax was 0.23 ± 0.05°/mm, which amounts to only 63.8 % or the average maximum torsion of the control group. However, when comparing patients with and without late gadolinium enhancement we found no significant difference in maximum torsion.When comparing the subgroups EF+ and EF-, we found a significantly lower myocardial Tmax and EF  shown in Fig. Tmax and age , which was also present separately in the epicardial and endocardial bands , as shown in Fig. p = 0.4).We found a strong positive correlation between Tmax were significantly reduced for patients with reduced EF (EF-) when compared to patients with preserved EF (EF+) and controls . Similarly, patients with wall motion abnormalities WM+ had significantly lower transmural torsion difference ∆Tmax, compared to the controls and patients without wall motion abnormalities WM- , as shown in Fig. Tmax amounted to 0.08 ± 0.05°/mm, which is only 50 % of the average torsion difference for the control group.The difference between endocardial and epicardial torsion ∆Tmax  and ∆%Tmax . Additionally we observed a significant increase of ∆Tmax  with age, as shown in Fig. In Fig. Figure p = 0.004) and patients with preserved ejection fraction EF+ . Peak torsion was reached by the epi- and endocardial torsion curves concomitantly, i.e. we measured no statistically significant temporal delay. For this reason, when computing the difference between endo- and epicardial maximum torsion, we simply subtracted the absolute maxima of each curve, as previously defined in Eq. The torsion curves reach a maximum during the end-systolic phase when the LV was fully contracted. The average maximum endocardial torsion was significantly larger than the epicardial torsion for both volunteers  in patients with preserved ejection fraction . For exaMyocardial torsion can be computed between any pair of short-axis slices, taking into account their variable distance and radii. The base-mid torsion has generally higher values than the base-apex and mid-apex, especially for non-ischemic cardiomyopathy patients with preserved ejection fraction. However, the base vs. apex torsion parameter has the advantage of quantitatively describing the twisting motion of the entire left ventricle over time.Furthermore, our results showed that myocardial torsion was higher in the endocardial tissue layer compared to the epicardial tissue layer in subjects with normal heart function. This is in accordance with the observation of a more dynamic motion pattern in the sub-endocardial fibers, which have a higher velocity than the epicardial during the cardiac cycle , 33. In Moreover, we examined the variation of absolute and relative difference between endo- and epicardial torsion for our patient subgroups. Our correlation analysis showed that the difference in dynamics between the endocardial and epicardial fiber clusters was significantly smaller for patients with reduced cardiac function. We observed a reduction in the maximum torsion difference between the endo- and epicardial layers, both in absolute and relative values, for progressively higher LV dysfunction. More specifically, the transmural difference in torsion was reduced close to zero for patients with ejection fraction smaller than 40 %.The difference in torsion between endo- and epicardial layers was also associated with age. As the myocardial microfibers continue to grow throughout an adult’s life, the helical architecture becomes more elaborate. Evidence of an increase in fiber twist due to this remodeling has also been reported with other methods. Omar et al.  reportedOur present study only included patients with reduced ejection fraction or wall motion abnormalities, without distinguishing between the causes for the dysfunction. As a first step, our goal was to test our method for quantifying myocardial torsion based on TPM and its capability to distinguish between patients with normal and abnormal cardiac function, as well as to explore the potential of quantifying the relation between endocardial and epicardial torsion within these groups. However, the heterogeneity of the patient cohort is a significant limitation of the work. In the future, we plan to conduct more targeted studies using more specifically selected patient groups.In our study cohort, we did not find a significant change of torsion in the presence of late gadolinium enhancement, though such findings were previously reported (using tagging on humans  and animOne drawback of the TPM CMR acquisition method used in this study is the relatively long breath-hold time required. Some of the patients in our cohort had signs of dyspnea, which can lead to incomplete breath holding during the acquisition and thus imperfect image quality. Nevertheless, all TPM data could successfully be analyzed to determine torsion and transmural torsion difference. Also, there is tradeoff between the temporal resolution that can be acquired and the required scan and breath-holding time. Overcoming such limitations and imaging myocardial velocities with a higher temporal resolution could better characterize the complex wall motion pattern.Another limitation is the relatively high sensitivity of our measurement to the myocardium segmentation. Especially in apical slices, the lack of contrast between blood pool and myocardium in the magnitude image combined with the low velocities in the phase images makes the myocardium segmentation very challenging, even as a manual task. As a consequence, we observed outliers in the Bland-Altman analysis, which led to a moderate overall reproducibility of our method. Furthermore, in case of the outliers, the slightly different orientations of the short-axis plane positioning between scan and rescan also accounts for the larger variations. Variability in the apex segmentation could also be a reason why the torsion parameters showed relatively high variability even among healthy subjects, but further investigation is required to establish the normal limits of these variations. Therefore we think that the myocardium segmentation used to analyze velocity images should be subjected to a higher standard of precision and results from automatic and semi-automatic segmentation method should be carefully monitored corrected for optimal results.As the thickening of the myocardium during systole is more substantial in the endocardial region compared to the epicardial, another limitation of the segmentation approach is always considering the centerline to separate between the epicardial and endocardial regions of the myocardium. In the future we will track the myocardium centerline with a similar approach which was used to propagate the manual myocardium contours from a single time point to the entire image series.TPM-based quantification of myocardial torsion was employed to derive information about changes in cardiac motion induced by non-ischemic cardiomyopathy. The maximum LV torsion could be used to detect significant differences between patients with preserved or reduced global cardiac function and was sensitive to wall-motion abnormalities, thus showing potential as a biomarker for cardiovascular disease. We have also gained new inside in the difference in torsion between the endocardial and epicardial layers and their relationship to global cardiac function. Further TPM studies are planned to investigate the variation of myocardial torsion with specific cardiovascular diseases, and the possibility of using torsion-related parameters to detect early onset or severity of cardiac diseases.


In patients with phaeochromocytoma, acute or chronic exposure to catecholamines may lead to cardiac pathology, including left ventricular (LV) hypertrophy, myocardial infarction, stress-induced cardiomyopathy and heart failure. The burden of myocardial involvement in this disease with systemic effects is unknown. In this prospective, multicentre study, we sought to describe the variety and incidence of cardiac abnormalities in patients diagnosed with phaeochromocytoma using multi-parametric cardiovascular magnetic resonance (CMR) imaging.We studied 50 patients diagnosed with phaeochromocytoma. Twenty patients  newly-diagnosed with confirmed phaeochromocytoma prospectively underwent CMR before and after curative surgical resection of the phaeochromocytoma (median follow-up 1 year). In addition, 30 patients  previously diagnosed with phaeochromocytoma who had curative surgery were also recruited for cardiac characterisation. Patients with known cardiac conditions were excluded. CMR included cine imaging for global and regional LV function, dark-blood T2-weighted imaging for oedema and late gadolinium enhancement imaging to detect the presence and patterns of any scarring.In patients with newly-diagnosed phaeochromocytoma, the mean LV ejection fraction was 67±10% (EF range 47-88%); of these patients, 20% (n=4/20) had mild global LV dysfunction (EF 47-56%). A significant proportion  demonstrated scarring, all with a non-ischaemic pattern, but these areas were small (<10% myocardium); no patient had evidence of myocardial infarction . One patient demonstrated global myocardial oedema with normal EF. All LV dysfunction or oedema were reversible and normalised at postoperative follow-up. In patients previously-diagnosed who already had had curative surgery, the mean LVEF was essentially normal (73±7%) with only one patient (3%) who had mild global LV dysfunction (EF=56%). Compared to the newly-diagnosed patients, a significantly smaller proportion of previously-diagnosed patients  demonstrated areas of scarring, which were also small in areas with a non-ischaemic pattern, except for one patient who suffered a small myocardial infarction.Subclinical cardiac abnormalities are frequent findings on CMR in patients newly-diagnosed with phaeochromocytoma, including mild LV dysfunction, myocardial oedema and small areas of non-ischaemic scarring, with the former two demonstrating normalization after surgical resection of the phaeochromocytoma. In patients who had previously undergone curative surgical resection of their phaeochromocytomas, the incidence of cardiac abnormalities is lower, predominantly consisting of small areas of non-ischaemic fibrosis.VMF and SKP acknowledge funding from the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre based at The Oxford University Hospitals NHS Trust and the University of Oxford.VMF received funding from the Alberta Innovates Health Solutions (AIHS) Clinical Fellowship and the University of Oxford Clarendon Fund Scholarship. SN acknowledges support from the British Heart Foundation Centre of Research Excellence, Oxford.


It is unclear if children after heart transplantation (HTX) are at risk for developing increased myocardial fibrosis. Diffuse myocardial fibrosis can be estimated by myocardial longitudinal relaxation (T1) times.Twenty cardiovascular magnetic resonance (CMR) studies in 17 patients after HTX  were analysed retrospectively and compared to CMR studies in nine healthy controls . Patients with clinically significant rejection were excluded. T1 measurements were performed at a single mid-ventricular short axis slice orientation before and > 10 minutes after the application of 0.2 mmol/kg gadopentetate dimeglumine (Gd) in the interventricular septum (IVS), LV lateral wall and the complete LV myocardium (Image). The tissue-blood partition coefficient was calculated as a function of the ratio of T1 change of myocardium as compared to blood.Pre-contrast T1 times before the application of Gd were significantly higher in HTX patients compared to controls , whereas the reduced post-contrast T1 times in the HTX patients showed a trend towards being shorter than in controls but failed to reach statistical significance. Tissue-blood partition coefficients were elevated in patients after HTX in the LV lateral wall  and the complete LV myocardium . The difference in the IVS failed to reach statistical significance .Diffuse fibrosis is present in children after HTX as evidenced by pre- and post-contrast myocardial T1 mapping. The technique may be suitable for the detection of early signs of adverse remodeling after HTX.This study was partly funded by the Labatt Family Heart Centre, Witchell Fellowship, and by Siemens.


Contrast enhanced SSFP (CE-SSFP) and T2-weighted triple inversion recovery imaging (T2w) have both been clinically validated for determining myocardium at risk (MaR) by cardiovascular magnetic resonance (CMR), using myocardial perfusion SPECT (MPS) as reference standard. Previously, MPS has been used to describe the coronary perfusion territories during myocardial ischemia. Compared to MPS, CMR offers superior image quality and logistical advantages. The aim of this study was to describe the coronary perfusion territories of LAD, RCA and LCx based on CMR data using CE-SSFP and T2w in patients after ST-elevation myocardial infarction.CE-SSFP and T2w data from the recently published international multi-center trials CHILL-MI and MITOCARE, was used to assess MaR. CE-SSFP images from 206/212 patients (6 excluded due to inability to detect MaR) and T2w images from 147/212 patients  were included. Late gadolinium enhancement (LGE) imaging was used to assess infarct size. Imaging was performed on systems from three different vendors  and data was analyzed by a core laboratory. Culprit vessel was determined using angiography.Average size of MaR was greater for LAD  than for both LCx  and RCA . A comparison of coronary perfusion territories between CMR and previously published MPS data is shown in The perfusion territories of the three main coronary arteries were described using CE-SSFP and T2w in patients with acute myocardial infarction and resemble previous territories by MPS, with expected overlap between RCA and LCx.


Guidelines advocate using B-type natriuretic peptides in the diagnostic work-up of suspected heart failure (HF). Their main role is to limit echocardiography rates by ruling out HF/LV dysfunction where peptide level is low. Recommended rule-out cut points vary between guidelines. The utility of B-type natriuretic peptides in the very old (85+) requires further investigation, with optimal cut points yet to be established. We examined NT-proBNP's utility, alone and in combination with history of myocardial infarction (MI), as a rule-out test for LV dysfunction in very old people with limiting dyspnoea.Design: Cross-sectional analysis.Setting: Population-based sample; North-East England.Participants: 155 people (aged 87-89) with limiting dyspnoea.Measures: Dyspnoea assessed by questionnaire. Domiciliary echocardiography performed; LV systolic/diastolic function graded. NT-proBNP measured (Roche Diagnostics). Receiver operating characteristic analyses examined NT-proBNP's diagnostic accuracy for LV dysfunction.AUC for LVEF less than or equal to 50% was poor , but good for LVEF less than or equal to 40% . At ESC cut point (125ng/l), few cases of systolic dysfunction were missed , but echocardiography (88%) and false positive rates (56-81 per 100 screened) were high. At NICE cut point (400ng/l), echocardiography (51%) and false positive rates (33-45) were lower; exclusionary performance was good for LVEF less than or equal to 40% , but poor for LVEF less than or equal to 50% . Incorporating isolated moderate/severe diastolic dysfunction into target condition increased the proportion of cases missed (lower NPV), whilst improving case detection. Incorporating MI history as an additional referral prompt slightly reduced the number of cases missed at expense of higher echocardiography and false positive rates.High echocardiography rates and poor exclusionary performance for mild degrees of systolic dysfunction and for diastolic dysfunction limit NT-proBNP's utility as a rule-out test for LV dysfunction in very old people with limiting dyspnoea. Incorporating MI history as an additional echocardiography prompt yields no overall benefit compared to using NT-proBNP level alone.The online version of this article (doi:10.1186/1471-2261-14-128) contains supplementary material, which is available to authorized users. The very old aged 85+), the most rapidly expanding age group worldwide,  comprise+, the moThe B-type natriuretic peptides, BNP and NT-proBNP, offer a less expensive and more accessible diagnostic test for HF and LV dysfunction. Clinical guidelines advocate their use in the diagnostic work-up of suspected HF to limit the number of potential cases requiring echocardiography, by ruling out the condition where natriuretic peptide level is low, although recommended rule-out cut points vary between guidelines , 8. A raWe previously reported high prevalence of LV systolic and diastolic dysfunction in the very old, most cases being both symptomatic and undiagnosed . We hereThe recruitment strategy for the Newcastle 85+ Study has been reported . In briei BT06 with i2 performance package; GE Healthcare, USA). A standardised protocol was followed, conforming to guidelines from the American and British Societies of Echocardiography [Echocardiography was conducted in the home setting (own or care home) by one experienced echocardiologist who interpreted all scans. M-mode, two dimensional (2-D) and Doppler echocardiography - including tissue Doppler measurement of LV long axis velocities - was performed using a portable instrument . The between-batch coefficient of variation is 1.5-3.5% from 122-4322ng/l, with an analytical range of 5-35000ng/l.The laboratory performing the NT-proBNP assay and the echocardiologist were blinded to the echocardiographic and NT-proBNP data respectively.Methods for additional data reported are detailed in the Supplementary Appendix . Written informed consent was obtained from participants; where people lacked capacity to consent, for example because of cognitive impairment, a formal written opinion was sought from a relative or carer.Stata Statistical Software: Release 12. College Station, TX: StataCorp LP.), with statistical significance at α = 0.05.NT-proBNP’s distribution was non-Gaussian, therefore group comparisons were conducted on log transformed data (using t-tests). Receiver Operating Characteristic (ROC) analyses were conducted to determine NT-proBNP’s discriminatory ability for four categories of LV dysfunction (target conditions): any grade of systolic dysfunction (LVEF≤50%); moderate/severe systolic dysfunction (LVEF≤40%); a composite of either any grade of systolic dysfunction or isolated moderate/severe diastolic dysfunction; and a composite of either moderate/severe systolic dysfunction or isolated moderate/severe diastolic dysfunction. Standard errors for the area under the ROC curve (AUC) were determined using the method outlined by DeLong et al. . NT-proBThe derivation of the analysed sample  is shown in Figure Whilst there was notable overlap in NT-proBNP distribution across six groups defined by LV function, all dysfunction groups had significantly higher NT-proBNP than the group with no systolic dysfunction and no diastolic dysfunction graded more severe than mild  0.49-0.65), whilst that for moderate/severe systolic dysfunction was good  Table . DefininTable We also examined test performance at two confirmatory or rule-in cut points  recommends that individuals with a previous MI should be referred directly for echocardiographic evaluation, without preliminary natriuretic peptide measurement; those without previous MI should be referred on the basis of natriuretic peptide level . We examWe report novel data on the utility of NT-proBNP, alone and in combination with MI history, as a rule-out test for LV systolic and diastolic dysfunction in very old people with limiting dyspnoea. The rule-out cut points recommended by the ESC (125ng/l)  and NICEThrough comparison with our data-derived cut points, it appears that the ESC cut point is generally an appropriate ‘stringent’ rule-out cut point (misses few cases) in the very old, whilst the NICE cut point is an appropriate ‘optimised’ rule-out cut point . However, whilst these may be the most appropriate cut points for this age group, their performance metrics limit their overall utility. Interestingly, the NICE cut point has been criticised as being too high, with lower age-specific optimised rule-out cut points recommended ;  our dataNT-proBNP’s limited diagnostic accuracy for LV dysfunction in the very old is likely to reflect the high prevalence of other cardiac and non-cardiac morbidities known to elevate natriuretic peptides,  compoundFew studies have examined the diagnostic accuracy of natriuretic peptides in older people,  with theStrengths of this study are its population-based sample, including the institutionalised and cognitively impaired, and its domiciliary echocardiographic approach incorporating assessment of both systolic and diastolic dysfunction. Hospital-based assessment of this age group is known to introduce selection bias . A limitHigh echocardiography rates and poor exclusionary performance for mild degrees of systolic dysfunction and for diastolic dysfunction limit NT-proBNP’s utility as a rule-out test for LV dysfunction in very old people with limiting dyspnoea. Therefore alternative strategies merit consideration. These might include other blood-based biomarkers, either singly or in combination panels, although a recent study in a care home population found the novel biomarkers copeptin, MR-proADM and MR-proANP to have little diagnostic utility in older people with significant co-morbidity . ClinicaSupplementary Appendix: supplementary methods and results.(DOCX 264 KB)Additional file 1:


We aim to deliver large appliances into the left ventricle through the right ventricle and across the interventricular septum. This transthoracic access route exploits immediate recoil of the septum, and lower transmyocardial pressure gradient across the right versus left ventricular free wall. The route may enhance safety and allow subxiphoid rather than intercostal traversal.The entire procedure was performed under real-time CMR guidance. An “active” CMR needle crossed the chest, right ventricular free wall, and then the interventricular septum to deliver a guidewire then used to deliver an 18Fr introducer. Afterwards, the right ventricular free wall was closed with a nitinol occluder. Immediate closure and late healing of the unrepaired septum and free wall were assessed by oximetry, angiography, CMR, and necropsy up to four weeks afterwards.The procedure was successful in 9 of 11 pigs. One failed because of refractory ventricular fibrillation upon needle entry, and the other because of inadequate guidewire support. In all ten attempts, the right ventricular free wall was closed without hemopericardium. There was neither immediate nor late shunt on oximetry, X-ray angiography, or CMR. The interventricular septal tract fibrosed completely. Transventricular trajectories planned on human CT scans suggest comparable intracavitary working space and less acute entry angles than a conventional atrial transseptal approach.Large closed-chest access ports can be introduced across the right ventricular free wall and interventricular septum into the left ventricle. The septum recoils immediately and heals completely without repair. A nitinol occluder immediately seals the right ventricular wall. The entry angle is more favorable to introduce, for example, prosthetic mitral valves than a conventional atrial transseptal approach. Implanting large appliances into the heart, such as investigational transcatheter mitral or aortic valves, will require large introducer sheaths. Transfemoral arterial access may be limited by vessel caliber or disease ; transvaWe have proposed closed-chest direct transthoracic closure of large access ports directly across the LV free wall using nitinol cardiac closure devices , and of These observations led us to propose an alternative closed-chest large-port access route intended (1) to allow entry across the mitral valve orifice; (2) to exploit the reduced leakage pressure gradient across the RV free wall to allow safe closure compared with leakage pressure across the LV free wall; (3) to test the immediate recoil and late healing of large unrepaired sheath ports across the interventricular septum; and (4) to allow a subxiphoid rather than intercostal route.We hypothesize that 18Fr sheaths can be introduced into beating LV in animals successively across the chest wall, RV free wall, and interventricular septum; that the interventricular septum closes immediately and thereafter fibroses completely; and that the large RV free wall hole can be closed with a nitinol closure device intended to seal atrial septal defect. We perform these procedures in swine using real-time CMR guidance to provide global imaging context of the transthoracic procedure.Animal procedures were approved by the institutional animal care and use committee according to contemporary NIH guidelines. The study was performed in 11 naïve Yorkshire pigs (49 ± 6 kg), after a period of technical development in separate animals. Anesthesia was induced with ketamine, midazolam and glycopyrrolate and maintained with inhaled isoflurane and mechanical ventilation. For survival experiments, percutaneous catheters (see below) were removed and animals provided a fentanyl patch and ketoprofen analgesia as needed.We customized an 18 G CMR-compatible nitinol needle to enhance its visibility during CMR . By addiGlidewire, Terumo Medical Corporation or Nitrex Guidewire, EV3 Inc.) were used to exchange sequentially for an 8Frx10cm short introducer sheath  and then a custom 18Fr introducer sheath. We customized a commercial introducer  to shorten the sheath from 30 to 15 cm, and we designed and printed a dilator lock to secure it to the sheath hub , shown in Figure After accessing the LV cavity, off-the-shelf stiff nitinol wires . We modified the delivery cable to incorporate a loopless antenna to enhance visibility during CMR [At the conclusion of procedures, the RV free wall entry site was closed using an off-the-shelf nitinol atrial septal occluder  is configured for interventional guidance as described previously [Interactive Front End, Siemens) connected to the CMR scanner provides a graphic user interface for interactive slice and scan control and low-latency reconstruction of real-time multislice CMR. The prototype is further customized with NHLBI features including interactive slice thickness, interactive projection mode, and interactive saturation magnetization preparation. In-lab LCD projectors display scanner control, real-time imaging, and instantaneous hemodynamics. Operators wear acoustic noise cancellation headsets and microphones to communicate all at once to team members in- and outside the laboratory .The CMR suite  CMR, as well as late gadolinium enhancement using gadopentetate-dimeglumine 0.2 mmol/kg. Typical real-time CMR parameters were: bSSFP; FOV, 350 mm; slice thickness, 6 mm; TR/TE, 2.88/1.44 ms; flip angle 40 degrees, matrix, 192×144, parallel imaging rate 2, temporal resolution 242 ms per slice. Images were constructed and projected on a screen inside the MR suite for the operators.ex-vivo CMR examined the transseptal tract scar. 3-dimensional T1-weighted spoiled gradient echo achieved 0.6 mm isotropic voxel resolution using TR/TE, 10.0/5.35 ms; 8 averages, 100-120slices per slab; flip angle, 20°; matrix, 320×320×144; FOV, 200 mm.High resolution Separate non-survival experiments were performed in 9 animals to explore initial techniques. Early failure modes included: inadequate skin incision to allow large-sheath entry; and inadequate guidewire support to deliver the 18Fr introducer sheath. Thereafter we performed prospective survival experiments on 11 additional animals reported here.At baseline, a subxiphoid pericardial drain was placed at baseline to instill fluid to separate the pericardial walls and allow appropriate positioning of the epicardial disc of the nitinol closure device  . PercutaCMR guided three key procedure steps. First, a transthoracic needle trajectory was selected. Considerations include avoiding interposed bony structures and intercostal spaces, minimal interposed lung, and a pathway from the RV free wall towards the interventricular septum that enters the mid-LV cavity without papillary muscle injury or entrapment. The trajectory was planned interactively using a finger on the chest surface, and images were stored as a roadmap for subsequent CMR slice prescription. It is important to note that while we are modeling a subxiphoid procedure for human use, the rotation of the porcine heart requires a right lateral transthoracic trajectory in these experiments.Glidewire, Terumo) delivered a large 18Fr introducer port modified as described above (Catheter Devices).Next the needle was advanced percutaneously during real-time CMR using two interleaved long-axis images for guidance. The shallow needle trajectory is ergonomically suitable for both animal and operator inside the CMR bore. LV cavity entry was confirmed with imaging and pressure measurements before a passive 0.035” × 150 cm nitinol guidewire  was used to place a small (8Fr × 10 cm) introducer sheath. Next an air-filled balloon wedge endhole catheter  was exchanged into the LV and manipulated into a pulmonary vein or the descending aorta to achieve safe guidewire purchase for the next step. Next a stiff 0.038” nitinol guidewire  disc to be deployed along the epicardial border.Follow-up was designed to detect early or late hemopericardium, iatrogenic myocardial dysfunction, and to characterize the extent of myocardial injury caused by the trans-ventricular access tract.After RV closure the animals were observed for two hours, before follow-up CMR and catheter angiographic and oximetric assessment.ex-vivo late gadolinium enhanced (3D T1-weighted) CMR. Necropsy and histopathology by a dedicated veterinary pathologist evaluated the presence of ventricular septal defect or scar.Late CMR follow-up was performed on day 4 and week 4, including cine CMR for function and pericardial effusion, and late gadolinium enhancement for interventricular septum inspection. Animals were euthanized after four weeks and the heart extracted for high resolution We assessed the anatomic feasibility of transthoracic interventricular septal access in humans using an anonymized and de-linked series of adults with suspected cardiovascular disease undergoing contrast-enhanced computed tomography  extending to the abdomen using ECG-gated breath-held acquisitions . These do not constitute human subject research under US 45CFR§46.102(f).LV mass, function, scar volume, and trajectory geometries were measured using a CMR workstation . Paired continuous parameters were compared using a Student t-test. Serial continuous parameters were tested using ANOVA. A p value < 0.05 was considered significant.After initial technique development in 9 animals, survival experiments were performed in 11 additional swine, and were successful in 9. One failed because of refractory ventricular fibrillation immediately after LV puncture. In the other, the large sheath failed to deliver because we had not yet learned to use deep guidewire support in the left atrium or aorta. This animal recovered uneventfully after RV port closure. The technique was modified in response to both .Figure No ventricular septal defect was evident immediately after port closure, either by oximetry Table , X-ray aAfter the 18Fr (7.3 mm sheath outer diameter) port was introduced across the RV into the LV, the RV free wall hole was closed under real-time CMR guidance using an Atrial Septal Occluder 6-8 mm , including among individual animals. No regional wall motion abnormality was detected.in-vivo revealed a low-volume interventricular septal scar along the sheath tract. This tract was better depicted using high-resolution ex-vivo CMR , and in the other, after defibrillation the procedure continued without incident.One animal had a large and two others small reactive (serous) pericardial effusion at 4 weeks, and one had a small right pleural effusion.There were no cases of hemopericardium after RV free wall closure. There was no evident ECG conduction delay in any animal. There was no evident pneumothorax or lung injury.Although these porcine experiments necessarily used a right lateral transthoracic trajectory, we examined the feasibility of a subxiphoid trajectory to the LV through the RV and interventricular septum in 21 patients  who underwent cardiac computed tomography with abdominal and thoracic coverage for cardiovascular disease. We measured geometry of theoretical trajectories using our novel subxiphoid-transventricular approach, and using “conventional” approach across the interatrial septum, comparing intracameral “working space” (distance) and catheter angulation Figure .The distance from the skin to the RV epicardium was 50 ± 12 mm. The distance from the RV epicardium to the LV endocardium through the interventricular septum was 45 ± 6 mm. Table We have demonstrated a new closed-chest transthoracic access procedure into the beating LV across the interventricular septum. This approach sequentially traverses the RV free wall and then the interventricular septum instead of the LV free wall. The cavity-to-pericardial (“leakage”) pressure gradient is lower for a RV free wall entry compared with LV free wall entry, and in this way our trajectory may enhance acute procedural safety of closed-chest direct cardiac access. Translated into patients, our approach would allow subxiphoid introduction of large appliances into the heart without surgery, for example transcatheter mitral valves having delivery systems 10 mm wide or more . In thisTo our surprise during the conception of this experiment, the 7.3 mm diameter iatrogenic ventricular septal defect recoiled acutely and then healed spontaneously and completely in every case. This is consistent with reports of spontaneous closure of traumatic ventricular septal defects, summarized by Dehgani and colleagues . This alPossible advantages of our approach compared with surgical or percutaneous transapical LV access include (1) subxiphoid access without intercostal injury and pain for transthoracic transapical access; (2) reduced cameral-pericardial pressure gradient contributing to bleeding across the access tract; (3) lower likelihood of major epicardial coronary artery injury from access across the RV free wall compared with the LV apex; (4) an extrapleural and subxiphoid trajectory reducing the risk of pulmonary injury and avoiding intercostal width and trajectory constraints. Possible disadvantages of our approach include (1) injury to the interventricular septum causing a persistent ventricular septal defect or conduction abnormality, even though we observed neither in this preclinical experience; (2) shorter intracavitary “working distance” to the mitral or aortic valves compared with transapical access, and angulated entry to the aortic valve; (3) possible interference with the endocardial closure device by RV mural trabeculation, a phenomenon we did not observe in this preclinical experience; and (4).pulmonary hypertension related valve disease might reduce the proposed benefit of lower pressure gradient across the RV free wall.There is little tolerance for risk in a transcatheter alternative to surgery. For this procedure, we have developed techniques to mitigate risk. First, a separate pericardial catheter drain is placed at the beginning of the procedure, intended to separate the pericardial walls by transient fluid installation. This drain can decompress the pericardium in an emergency. Second, an ancillary “buddy” guidewire may allow transcatheter rescue should the nitinol closure device accidentally be withdrawn through the right ventricular free wall. In our prior preclinical report of direct transthoracic repair of ventricular septal defect , inadverReal-time CMR provided superb guidance for trajectory planning, needle access, guidewire and sheath delivery, and the RV free wall closure. CMR has an advantage over X-ray or ultrasound guidance in providing soft-tissue images in any arbitrary orientation, independent of acoustic windows imposed by ribs or air. Most important, the large field of view provided by real-time CMR provides a global thoracic context of the procedure allowing the operator to avoid bystander tissue injury and monitor instantaneously for complications ,16.This work has noteworthy limitations. The procedure succeeded in only 9 of 11 animals. One failure is attributed to needle-induced ventricular fibrillation, which is common in swine. Another failure is attributed to immature catheter technique, from failure to obtain deep purchase of a rigid guidewire in order to deliver the cardiac sheath. Late complications were evident in one animal, manifest as serous (reactive) pericardial effusion without signs of tamponade. In clinical practice we would expect to leave a pericardial drainage catheter in place for one or more days in an attempt to prevent pericardial effusion. Real-time CMR remains investigational, although early human CMR catheterization procedures are being undertaken ,23.We have developed a novel non-surgical approach to introduce large structural implants into the LV. A subxiphoid introducer sheath is placed across the RV free wall and from there across the interventricular septum into the LV. The entry angle for mitral valve implants is less acute than a conventional atrial transseptal trajectory. The RV free wall hole is closed with a nitinol occluder device. Surprisingly, the interventricular septum hole closes immediately and completely, and afterwards heals as a small fibrous tract.ECG: Electrocardiogram; FOV: Field of view; CMR: Cardiovascular magnetic resonance; LV: Left ventricle; RV: Right ventricle; TE: Echo time; TR: Repetition time.NIH and Siemens Medical Systems have a collaborative research and development agreement for CMR.Kanishka Ratnayaka serves without compensation on a Siemens Pediatric Advisory Council. Michael Slack is compensated as physician proctor for St Jude Medical.MH designed and performed experiments, analyzed the data, and prepared and edited the manuscript. KR, AZF, MSH, IMB JRW, MYC, MCS, OK, WHS, VJW assisted in experiments and edited the manuscript. MAE performed necropsy and histopathology analysis. RJL designed experiments, analyzed the data, and prepared and edited the manuscript. All authors read and approved the final manuscript.


Idiopathic inflammatory myopathies are heterogeneous systemic autoimmune diseases that are characterized by progressive muscle weakness and typical inflammatory infiltration in skeletal muscle. It is known that a cardiac involvement may occur; the frequency varies between 9% and 72%, mainly depending on patient selection and diagnostic procedures applied. Most common finding is a progressive (systolic) heart failure. Diagnosis may be difficult in patients that exhibit exercise limitation due to peripheral muscle weakness.It has been shown that cardiac magnetic resonance imaging (CMR) is reliably able to provide important information concerning cardiac function and inflammatory processes in a single exam. Therefore, objective of our prospective study was to assess and characterize myocardial involvement in patients with histological defined idiopathic inflammatory myopathies by a comprehensive CMR protocol.Fifty-three consecutive patients with histologically proven idiopathic inflammatory myopathy were enrolled into the study.All patients underwent CMR examination in a 1.5-T whole body scanner using a 32-channel phased-array cardiac surface coil. Volumetric and functional assessment was performed using 3D short-axis steady-state free precession sequences covering the entire left and right ventricle. Early myocardial enhancement was assessed before and shortly after the admission of gadolinium based contrast agent by T1-weighted fast spin-echo sequences. Inversion-recovery gradient-echo sequences were acquired for the evaluation of late gadolinium enhancement (LGE) 10-15 minutes after administration of 0.2 mmol/kg gadolinium based contrast agent .CMR images were analyzed by two experienced and blinded readers in consensus.Reduced left ventricular function (ejection fraction < 60%) was present in 9 (17%) patients. These patients exhibited significantly higher blood levels of CK-MB  than patients with preserved LVEF. Early myocardial enhancement  was more often present  as well as LGE patterns consistent with myocardial inflammation . LGE was most often observed in the inferior and lateral segments.The results of this study show that CMR is able to detect cardiac involvement in idiopathic inflammatory myopathies. Early diagnosis using CMR could result in early therapy of heart failure, leading to beneficial ventricular remodeling and thus improving quality of life and survival in these patients.


PAH) is a severe form of pulmonary hypertension in which right ventricular (RV) afterload is increased and death typically occurs due to decompensated RV hypertrophy and failure. Collagen accumulation has been implicated in pulmonary artery remodeling, but how it affects RV performance remains unclear. Here, we sought to identify the role of collagen turnover, defined as the balance between collagen synthesis and degradation, in RV structure and function in PAH. To do so, we exposed mutant (Col1a1R/R) mice, in which collagen type I degradation is impaired such that collagen turnover is reduced, and wild‐type (Col1a1+/+) littermates to 14 days of chronic hypoxia combined with SUGEN treatment (HySu) to recapitulate characteristics of clinical PAH. RV structure and function were measured by echocardiography, RV catheterization, and histology. Despite comparable increases in RV systolic pressure , the impaired collagen degradation in Col1a1R/R mice resulted in no RV collagen accumulation, limited RV hypertrophy, and maintained right ventricular‐pulmonary vascular coupling with HySu exposure. The preservation of cardiac function in the mutant mice indicates a beneficial role of limited collagen turnover via impaired degradation in RV remodeling in response to chronic pressure overload. Our results suggest novel treatments that reduce collagen turnover may offer a new therapeutic strategy for PAH patients.Pulmonary arterial hypertension ( Pulmonary arterial hypertension (PAH) is a severe pulmonary vascular disease in which increased right ventricular (RV) afterload leads to decompensated RV hypertrophy, failure, and ultimately death  mice results in a collagen type I triple helix that is resistant to collagenase‐based degradation  using a combination of chronic hypoxia and SUGEN, a vascular endothelial growth factor receptor inhibitor, which recapitulates characteristics of human PAH  and Col1a1R/R (n = 10) mice were exposed to a combination of chronic hypoxia and SUGEN (HySu) for 14 days as previously described  in a controlled chamber and given a weekly treatment of SUGEN  at the dose of 20 mg/kg  and Col1a1R/R (n = 13) controls were placed in room air. The University of Wisconsin‐Madison Institutional Animal Care and Use Committee approved all procedures.Eight‐week old male and female Col1a1Immediately before RV catheterization, transthoracic echocardiography was done to assess cardiac function as previously described , cardiac output (CO), effective arterial elastance (Ea), and total pulmonary vascular resistance (TPVR) , preload recruitable stroke work (PRSW), and the slope of dP/dtmax‐end diastolic volume (Ved) relationship . RV hypertrophy was determined using the RV free wall weight normalized by the LV free wall weight plus the septum weight (S)   and treatment (control/HySu). Tukey's Honestly Significance Difference method was utilized to control the type I error when conducting multiple comparisons. Model assumptions for analyses were validated by examining normal probability plots. Ees was calculated as the slope of the linear fit to the end‐systolic pressure and volume points with a Pearson correlation coefficient of greater than 0.9. A two‐sided P‐value less than 0.05 was considered statistically significant. All analyses were conducted using R‐software version 3.2.2 .Data are reported as mean ± standard error. Parameters were evaluated using a two‐way analysis of variance (ANOVA) for strain . Body weight and LV + S weight were lower in mice exposed to HySu treatment compared to controls, but TL was not affected by the collagen mutation or treatment  ratios Fig. A,B, and P/dtmax and dP/dtmin were higher and lower, respectively, with HySu treatment , and RV contractility quantified by Ees, dP/dtmax‐Ved, and PRSW was larger only in the Col1a1R/R mice . The combined increase in RV afterload and a lack of increase in RV contractility led to a decrease in the ventricular–vascular coupling efficiency Ees/Ea in the Col1a1+/+ mice, indicating RV dysfunction . In contrast, RV afterload (Ea) in the Col1a1R/R strain did not change while RV contractility increased such that Ees/Ea was maintained, demonstrating preserved RV function in the Col1a1R/R strain. These results indicate that impaired collagen turnover limited RV overload and prevented ventricular–vascular uncoupling in severe PAH.Right ventricular contractility and afterload were assessed to determine the cardiovascular effects of impaired collagen turnover in PAH. Interestingly, despite equivalent RVSP, R/R mice . The total mechanical energy from ventricular contraction (PVA) increased to a similar degree with HySu treatment in both strains  and did not change in HySu‐treated Col1a1R/R mice , it did limit the increase in steady RV afterload (TPVR), which likely contributed to attenuated RV dysfunction and maintained ventricular–vascular coupling. A summary schematic of our approach and findings (shaded boxes) regarding the impact of collagen turnover on RV structure‐function changes in response to pulmonary hypertension is provided in Figure +/+ mice by larger RV/TL  (Fulton index) and in HySu‐treated Col1a1/TL Fig. . However/TL Fig. . The RV/+/+ mice, accompanied by a pronounced increase in the collagen type I/type III ratio. RV fibrosis is generally understood to impair diastolic function, but its effect on systolic function is less clear and may depend on the stage of the disease  has been shown to cause an increase in RV contractility (Ees) such that ventricular–vascular coupling (Ees/Ea) is maintained , RV contractility increased to match it such that ventricular–vascular coupling was unchanged.Differences in effective arterial elastance between the strains contributed to the difference in ventricular–vascular coupling efficiencies with HySu treatment. In mild PAH, an increase in RV afterload  RV EW/PVA shows similar trends due to Ees and Ea compared to the previously reported LV EW/PVA and (2) reducing collagen turnover though collagenase‐resistance in the Col1a1 protects against impaired ventricular mechanical efficiency.Increased RV afterload leads to a larger demand for myocardial oxygen, which was assessed using cardiac energetic parameters. PVA, which is correlated with myocardial oxygen consumption, was increased to a similar extent in all HySu‐treated mice. While the total oxygen demand increase was similar between the two strains, the EW increase was significant only in mutant mice. In a canine model, LV EW/PVA was shown to increase with A more comprehensive and RV function‐independent measurement of the RV afterload can be done by measuring pulmonary vascular impedance ex vivo (Vanderpool and Chesler In prior studies, we have observed significant changes in pulmonary vascular and RV function with 10 or 15 days of chronic hypoxia or 14 days of chronic hypoxia plus SUGEN treatment (Kobs et al. In summary, our results show that limiting collagen turnover via inhibiting collagen degradation through use of the Col1a1 mouse attenuates the maladaptive changes in right ventricular‐pulmonary vascular coupling and prevents RV hypertrophy and fibrosis in PAH. Understanding the role of collagen turnover in RV hypertrophy and function may lead to targeted clinical treatments to prevent maladaptive RV structural and functional changes in PAH.No conflicts of interest, financial or otherwise, are declared by the authors.