The proposed method is evaluated against gadolinium-enhanced 1H measurements in-vivo.A velocity-selective binomial excitation scheme for myocardial first-pass perfusion measurements with hyperpolarized 13C urea with the velocity-selective vs. conventional excitation, as well as standard 1H gadolinium-enhanced images. Signal-to-noise, contrast-to-noise (CNR) and homogeneity of semi-quantitative perfusion measures were compared between methods based on first-pass signal-intensity time curves extracted from a mid-ventricular slice. Diagnostic feasibility is demonstrated in a case of septal infarction.The proposed excitation with an echo-planar imaging readout was implemented on a clinical CMR system. Dynamic myocardial stress perfusion images were acquired in six healthy pigs after bolus injection of hyperpolarized 1H gadolinium data (9–15%). Overall image quality appears comparable between the velocity-selective hyperpolarized and gadolinium-enhanced imaging.Velocity-selective excitation provides over three-fold reduction in blood pool signal with a two-fold increase in myocardial CNR. Extracted first-pass perfusion curves reveal a significantly reduced variability of semi-quantitative first-pass perfusion measures (12–20%) for velocity-selective excitation compared to conventional excitation (28–93%), comparable to that of reference 13C first-pass perfusion CMR has been demonstrated in swine. Comparison with reference 1H gadolinium data revealed sufficient data quality and indicates the potential of hyperpolarized perfusion imaging for human applications.The feasibility of hyperpolarized The online version of this article (doi:10.1186/s12968-017-0364-4) contains supplementary material, which is available to authorized users. Cardiovascular Magnetic Resonance (CMR) perfusion imaging is widely used for the clinical assessment of myocardial ischemia and has proven its excellent diagnostic value . To incrConventional first-pass perfusion CMR  is basedDespite a long history of safe use of gadolinium contrast agents in patients with normal kidney function, linear gadolinium based contrast agents have recently come under scrutiny in the wake of reports of gadolinium accumulation after repeated administration of certain types of agents –12. To t13C–labeled molecules with >10′000-fold enhancement  pyruvate to measure cardiac metabolism in humans have been reported [Dissolution dynamic nuclear polarization (DNP) allows to produce solutions of highly polarized ancement  relativel models . Recentlreported .15N] glutamine with a particularly long T1 in-vivo [13C- labeled urea has been used to study perfusion in kidneys [Metabolically inert hyperpolarized substrates have been suggested as alternative contrast agents for perfusion measurements using DNP. HP001, a customized non-endogenous substrate has been shown to enable hyperpolarized perfusion assessment in rats . Endogen in-vivo . Most pr kidneys –26, live kidneys , 28 and  kidneys , 28 in r kidneys . Simulta kidneys .13C urea has recently been demonstrated in rodents [The feasibility of myocardial perfusion imaging using hyperpolarized  rodents . The par rodents . This ap13C urea.Dynamic metabolic imaging of hyperpolarized substrates in the heart typically relies on spectral-spatial excitation schemes, in which metabolites are excited depending on their chemical shift , 33. DowIn this work a velocity-selective tip-back excitation that mitigates polarization saturation inside the blood pool whilst retaining the suppression of blood pool signal is proposed. By integration of a bipolar velocity-encoding gradient into slice selection of a binomial excitation pulse, a velocity dependent phase shift in the blood pool signal is introduced, which can be utilized to preserve longitudinal magnetization in the blood pool. The method is validated using phantom measurements and the in-vivo applicability is demonstrated in swine. Myocardial signal-intensity time curves obtained with the proposed method are compared to conventional excitation and clinically used gadolinium enhanced perfusion CMR.φ of spins moving with velocity The accumulated phase WithAs phase encoding only occurs along the gradient direction When combined with a binomial 1–1 excitation separated by the bipolar gradient pair, motion induced phase accrual can be exploited to tip back the magnetization of spins moving along the gradient direction by adjusting the excitation phase of the second radio-frequency (RF) pulse.venc can be set to π by scaling amplitude G(t) and duration T of the bipolar gradients such that:Alternatively, the accumulated phase between excitations for a given velocity venc. Stationary spins inside the myocardium that do not accumulate motion-dependent phase effectively undergo two excitations, while the magnetization of moving spins inside the left ventricular blood pool is retained by tipping it back to the longitudinal axis by the second RF excitation. This excitation can be combined with any single-shot readout, such as echo-planar (EPI) or spiral imaging.This approach does not require adjustments of the excitation phase for the second RF pulse with the additional benefit of being relatively robust towards small deviations from the nominal velocity For through-plane motion, which is predominant for the left ventricular blood pool in short axis acquisitions, the bipolar gradients can be efficiently integrated into the slice selection scheme as illustrated in Fig. venc encodings as a function of through-plane velocity over the imaging slice is illustrated in Fig. venc encoding, the relative signal amplitude s in dependency of the through-plane velocity v can be determined as:The effective excitation pattern for various Mz in the blood pool can be estimated as:Conversely, the amount of preserved magnetization venc encodings, benefit from a wider stop band around the target velocities  to 8.4 ms (venc: 25 cm/s) on the clinical CMR system used in this study.As the phase evolution is symmetric, the sign of the velocity and encoding gradients can be neglected. For the encoding velocity, the magnetization will be fully restored, while deviations due to spatial flow variations or mis-setting of the encoding velocity will result in imperfect tip-back and residual signal according to Eqs. see Fig. , whilst see Fig. . This masee Fig. . The gap13C were acquired using a custom-made 4-channel transmit/receive coil array  while the 2-channel body coil was utilized to sample on the 1H frequency. Animals were placed in right recumbency inside the scanner bore to allow for optimal placement of the coil arrays. A peripheral pulse oximeter unit was used for cardiac synchronization.All measurements were performed on a clinical 3 T Ingenia wide-bore scanner  equipped with a gradient system delivering 30 mT/m maximum amplitude at 200 T/m/s slew rate. Data on 13C urea glycerol solution was prepared and doped with 18.5 mM AH111501 trityl radical. 1 mL samples were polarized for 4 h in a commercial 5 T SpinLab Polarizer  before dissolution using a buffer consisting of 30 mL 0.1% EDTA dissolved in water. Upon sample collection, the prepared solution was further diluted and cooled down with additional 4.5 mL of buffer at 0 °C to achieve body temperature for injection. 20 mL of the final 200 mM 13C urea solution were transferred to the scanner using an electromagnetic carrier device [A 6.4 M r device  built in1 relaxation times inside the 3 T magnet were measured for the neat solutions  and after dilution in porcine heparinized venous blood samples within 15 min after sampling. Two urea concentrations  were measured: 10% and 33%, with an observed T1 of 25 ± 2 s and 34 ± 0.5 s, respectively.Polarization levels were established in separate experiments and amounted to 48 ± 5% at time of dissolution and 29 ± 3% at time of injection. T1H imaging of a water tube embedded in a solid gel phantom. Water flow was adjusted to ~50 cm/s, which is in accordance with LV velocities typically observed in-vivo. A single 2D slice perpendicular to the direction of flow was acquired using a single-shot EPI readout. Signals inside the water tube as well as the stationary gel region were compared to simulations for the conventional single-pulse and the proposed tip-back excitation with varying venc encodings. All measurements were normalized to the water signal of the conventional excitation.The proposed excitation scheme was validated using 2, O2, isoflurane), pulse oximetry, temperature, direct arterial blood pressure, urine output, and arterial and venous blood gases were monitored continuously throughout the procedure. Hyperpolarized 13C urea and 1H gadolinium were administered through separate catheters in the femoral veins.Seven healthy female swine  were used for the experiments. All swine were premedicated, intubated and sheaths (5 F) were introduced into both femoral arteries and veins. 100 IU/kgBW Heparin was given intravenously and repeated every hour. General anesthesia was maintained with isoflurane (2% - 3%) by positive pressure ventilation with 100% oxygen. Heart rate and rhythm and variability (ECG), inspiratory and expiratory gases  at increasing infusion rates until the target heart rate of 120 bpm was reached. Upon reaching the target heart rate, infusion rates were kept constant during all imaging experiments. 20 mL of hyperpolarized In one animal, acute myocardial infarction in the apical septum was induced by permanent distal ligation of the left anterior descending coronary artery (LAD). Corresponding data was not included in the main analysis of this study, but used as demonstration of sensitivity of the proposed excitation scheme to detect ischemic myocardium. After the procedure, all animals were euthanized in deep anesthesia by lethal injection of pentobarbital.13C measurement, 1H phase-contrast images were acquired using a 2D short-axis cine sequence under stress condition. Sequence parameters were: FOV = 250 × 220 mm2, slice thickness 8 mm, in-plane resolution 2.5 × 2.5 mm2, TR = 4.8 ms, TE = 2.8 ms, FA = 7°, cardiac phases = 35, venc = 100 cm/s. These short-axis cine images were used to determine through-plane velocities and trigger delays for subsequent 13C perfusion CMR.Prior to each 2, slice thickness 8 mm, in-plane resolution 1.9 × 1.9 mm2, TR = 2.7 ms, TE = 1.35 ms, FA = 45°, cardiac phases = 60.Anatomical reference 2D cine short-axis CMR was performed using a balanced steady-state free precession gradient echo sequence with the following parameters: FOV = 350 × 280 mm13C perfusion images were acquired with cardiac triggering starting seven heart beats after the start of injection to minimize bolus saturation in the RV blood pool. Ventilation was suspended for the first 45 s of imaging to avoid misregistration between individual time frames. The proposed 1–1 binomial tip-back excitation (FA: 2 × 30°) was compared to single-pulse excitation (FA: 60°) in each animal under maintained stress condition with two hyperpolarized bolus injections, separated by 10 min. Identical single-shot echo planar imaging readouts were employed in both cases with following parameters: FOV = 110 × 110 mm2, slice thickness 15 mm, in-plane resolution 3.0 × 3.0 mm2, TR = 1 heartbeat, partial Fourier factor 0.65, readout duration 32 ms. Effective echo times for the proposed excitation increased from TE = 10.2 ms  to TE = 13.3–14.2 ms in dependence of flow encoding as illustrated in Fig. venc) between 25 cm/s and 52 cm/s (mean ± std.: 38 ± 7 cm/s) for the velocity-selective excitation were used based on measured through-plane velocities.Dynamic series of 1H gadolinium contrast-enhanced perfusion CMR under stress was performed as a reference method in each animal. A dose of 0.1 mmol/kg gadolinium , followed by a 30 mL saline flush was injected at a rate of 4 mL/s using a power injector . Dynamic image series were acquired every heart beat using a saturation-recovery spoiled gradient echo sequence with parameters: FOV = 220 × 210 mm2, slice thickness 10 mm, in-plane resolution 3.0 × 3.0 mm2, TR = 1.9 ms, TE = 0.7 ms, FA = 15°, WET saturation [Conventional turation  delay = 2. 1H images were then rotated, aligned and cropped to the FOV of the 13C images. Nyquist-ghosts of the EPI readout were removed by first order phase correction maximizing signal intensity in a predefined region of interest (e.g. LV blood pool). 13C coil combination was implemented as root of weighted sum of squares [All in-vivo images were reconstructed from raw data using MRecon  and zero-filled to a common resolution of 1 × 1 mm squares .13C perfusion and 1H reference images. The myocardium was subsequently divided into six segments corresponding to the basal/mid-ventricular slices in the 16 segment AHA model [Left ventricular myocardium and LV blood pool were manually segmented on overlays of HA model .1H and 13C scans, respectively.Coil sensitivities were estimated and corrected by fitting a plane over the myocardial signal at a time frame prior to and after bolus passage for 13C urea signal intensities were calculated as mean values over each segment and the LV blood pool. Global magnitude offsets were corrected for by subtraction of mean noise levels of the last 10 time frames in the image series.Three-parameter gamma-variate functionss(t) for further data analysis of 13C urea data. 1H gadolinium time curves were fitted with fourth order polynomials respectively. Area under the curve (AUC), peak myocardial contrast-to-noise ratio (pCNR) and up-slope were extracted from the fitted curves as semi-quantitative perfusion measures for 13C urea and 1H contrast-enhanced scans [1H) or post (13C) bolus [were fitted to the signal time curves ed scans . Signal-C) bolus . CNR wasC) bolus .1H gadolinium based measurements. Analysis was restricted to first-pass signal contributions in all cases. Coefficients of variance (CoV) were calculated as standard deviation divided by mean values. A paired, two-sided Wilcoxon signed rank test was employed for statistical comparisons. A p-value <0.05 was considered significant.Absolute values and variability over the six myocardial segments were compared between conventional and the proposed tip-back excitation, as well as to venc encoding strength show good agreement with the predicted signal overall. Encoding with the nominal velocity (48 cm/s) yields a > 80% reduction in water signal. Residual signal is observed at the tube boundary, where velocities deviate from the nominal value. Encoding with approximately half the nominal velocity (25 cm/s), which results in an accumulated phase of 2π, recovers 78% of the signal as expected due to inflow effects, stronger T2* weighting of the prolonged excitation and finite sharpness of the velocity distribution.Figure Figure 13C urea conventional excitation, 13C urea velocity-selective excitation and 1H gadolinium based contrast agent is shown. During LV bolus peak at 2 s (second column), blood pool signal suppression is apparent for the velocity-selective in contrast to conventional excitation. Residual LV signal stems from low blood flow near the trabeculae. Myocardial bolus signal (4–6 s) is significantly enhanced for the proposed method, with a clear distinction of right and left ventricular myocardium.In Fig. 1H gadolinium (Gd), 13C velocity-selective (VS) and 13C conventional (C) measurements. Mean myocardial SNR averaged over each sector was 18.4 ± 1.5 (Gd), 25.7 ± 2.6 (VS) and 15.1 ± 2.5 (C), respectively.Figure For conventional excitation, blood pool spillover in the septal sectors 1 and 2, as well as the lateral sector 5 is observed. Myocardial peak signal appears at an unphysiologically early time point with respect to the LV peak bolus. Velocity-selective excitation yields uncontaminated myocardial response curves with good homogeneity over the six sectors. Myocardial peak signal is observed at the physiologically expected time point 2–3 s after the LV blood pool signal peak. Up-slope, timing and homogeneity are comparable with signal curves obtained from gadolinium-enhanced measurements.P = 0.03) higher for conventional excitation (47 ± 53%) compared to 1H gadolinium (12 ± 6%) and velocity-selective excitation (14 ± 4%). Upslope variability shows the largest inter-sequence discrepancy: 15 ± 5% (Gd), 20 ± 9% (VS), 93 ± 61% (C).Intramyocardial coefficients of variance of semi-quantitative perfusion measures over six animals are evaluated for six animals in Fig. P = 0.03) lower for velocity-selective excitation (149 ± 117) compared to conventional excitation (473 ± 125), as illustrated in Fig. Peak SNR of LV blood pool is significantly (1H gadolinium (19.2 ± 3.7 vs. 9.6 ± 3.9), and a significant (P = 0.03) increase compared to conventional excitation (9.5 ± 3.5).Absolute myocardial peak CNR values are shown in Fig. 13C velocity-selective and 1H gadolinium-enhanced images. Extracted myocardial perfusion curves confirm the perfusion defect in AHA sector 2 in both datasets. Increased LV signal spillover is detected for the urea measurement.In Fig. P < 0.05), as well as good discrimination of LV blood pool signal have been shown. Direct comparison with 1H gadolinium data indicates that the proposed method can produce sufficient data quality for diagnostic purposes in large subjects.In this study, the feasibility of hyperpolarized myocardial first-pass perfusion CMR using velocity-selective excitation was demonstrated. Significantly enhanced SNR and CNR compared to conventional excitation . Short axis acquisitions are therefore especially suited, as the encoding gradients can be partly integrated into slice selection gradients without echo time penalty. Nevertheless, the encoding gradients can be applied along directions other than the slice selection direction for applications where different slice orientations (e.g. long axis) are required. In addition to an echo time penalty from temporal gradient separation, this approach would also require an additional bipolar gradient along the slice selection direction to compensate for the phase accrual generated by the binomial excitation. The feasibility and efficacy of such an approach remain to be investigated.Related to our work, the use of flow sensitizing gradients for the suppression of LV blood pool signal has previously been proposed . In contAs an alternative to the single-shot EPI readout used in this work, spiral k-space trajectories may be employed , 42, 43.1 decay and flip angle. Absolute perfusion quantification using hyperpolarized 13C substrates has been demonstrated in cancer, brain and kidneys [Qualitative and semi-quantitative perfusion CMR, as covered by this work, is diagnostically valuable for the detection of local ischemia. To reduce operator dependence during analysis and to enable the detection of absolute changes in perfusion, myocardial blood flow (MBF) quantification is preferred . However kidneys , 28, 45.13C urea has been presented. Direct comparison with 1H gadolinium measurements showed very good agreement, indicating the potential of hyperpolarized 13C urea perfusion imaging for diagnostic purposes.A velocity-selective excitation scheme for first-pass myocardial perfusion measurements using hyperpolarized


Although increased oxidative stress is a major component of diabetic hypertensive cardiomyopathy, research into the effects of antioxidants on cardiac remodeling remains scarce. The actions of antioxidant apocynin include inhibiting reactive oxygen species (ROS) generation by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and ROS scavenging. We evaluated the effects of apocynin on cardiac remodeling in spontaneously hypertensive rats (SHR) with diabetes mellitus (DM).Male SHR were divided into four groups: control ; SHR treated with apocynin ; diabetic SHR ; and SHR-DM treated with apocynin , for eight weeks. DM was induced by streptozotocin . Statistical analyzes: ANOVA and Tukey or Mann–Whitney.Echocardiogram in diabetic groups showed higher left ventricular and left atrium diameters indexed for body weight, and higher isovolumetric relaxation time than normoglycemic rats; systolic function did not differ between groups. Isolated papillary muscle showed impaired contractile and relaxation function in diabetic groups. Developed tension was lower in SHR-APO than SHR. Myocardial hydroxyproline concentration was higher in SHR-DM than SHR, interstitial collagen fraction was higher in SHR-DM-APO than SHR-APO, and type III collagen protein expression was lower in SHR-DM and SHR-DM-APO than their controls. Type I collagen and lysyl oxidase expression did not differ between groups. Apocynin did not change collagen tissue. Myocardial lipid hydroperoxide concentration was higher in SHR-DM than SHR and SHR-DM-APO. Glutathione peroxidase activity was lower and catalase higher in SHR-DM than SHR. Apocynin attenuated antioxidant enzyme activity changes in SHR-DM-APO. Advanced glycation end-products and NADPH oxidase activity did not differ between groups.Apocynin reduces oxidative stress independently of NADPH oxidase activity and does not change ventricular or myocardial function in spontaneously hypertensive rats with diabetes mellitus. The apocynin-induced myocardial functional impairment in SHR shows that apocynin actions need to be clarified during sustained chronic pressure overload. Systemic arterial hypertension and diabetes mellitus (DM) represent two important risk factors for cardiovascular disease, the leading cause of morbidity and mortality in the world , 2. The One of the major components of diabetic hypertensive cardiomyopathy is an increase in oxidative stress , 12, 13.Picrorhiza kurroa  × 1.04. LV function was assessed by the following parameters: midwall fractional shortening (MFS), tissue Doppler imaging (TDI) of mitral annulus systolic velocity (S’), myocardial performance index (Tei index), early and late diastolic mitral inflow velocities (E and A waves), E/A ratio, isovolumetric relaxation time (IVRT), TDI of early mitral annulus diastolic velocity (E’), and E/E’ ratio. Tissue Doppler variables (S’ and E’) were measured at the septal and lateral walls, and average values presented [Echocardiographic evaluation was performed before diabetes induction and at the end of the experimental period. We used a commercially available echocardiograph  equipped with a 5–11.5 MHz multifrequency probe, as previously described –41. Ratsresented .2 and 5 % CO2 (pH 7.38). The composition of the Krebs–Henseleit solution in mM was as follows: 118.5 NaCl, 4.69 KCl, 1.25 CaCl2, 1.16 MgSO4, 1.18 KH2PO4, 5.50 glucose, and 25.88 NaHCO3. The spring clips were attached to a Kyowa model 120T-20B force transducer and a lever system, which allowed for muscle length adjustment. Preparations were stimulated 12 times/min at a voltage 10 % above threshold.At the end of the experimental period, myocardial contractile performance was evaluated in isolated LV papillary muscle preparation as previously described , 44. Ratmax) was determined. A 15 min period of stable isometric contraction was imposed prior to the experimental period. One isometric contraction was then recorded for later analysis.After a 60 min period, during which the preparations were permitted to shorten while carrying light loads, muscles were loaded to contract isometrically and stretched to the apices of their length-tension curves. After a 5 min period, during which preparations performed isotonic contractions, muscles were again placed under isometric conditions, and the apex of the length-tension curve  addition to the nutrient solution [The following parameters were measured from the isometric contraction: peak developed tension (DT), resting tension (RT), time to peak tension (TPT), maximum tension development rate (+dT/dt), and maximum tension decline rate (−dT/dt). To evaluate myocardial contractile reserve, papillary muscle mechanical performance was evaluated after the following positive inotropic stimulation: 30 s post-rest contraction, extracellular Casolution . PapillaTransverse LV sections were fixed in 10 % buffered formalin and embedded in paraffin. Sections (5 µm thick) were stained with hematoxylin–eosin and collagen-specific stain picrosirius red (Sirius red F3BA in aqueous saturated picric acid) . In at lHydroxyproline concentration was measured in LV to estimate myocardial collagen content . Tissue Protein expression of type I  and type III collagen  and lysil oxidase  was analyzed by Western blot as previously described , 51. Samg for 15 min at 4 °C. The supernatant was assayed for total protein, lipid hydroperoxide, and anti-oxidant enzyme activity [2O2 over 60 s, at 240 nm. Enzyme activity was analyzed at 25 °C using a microplate reader system . All reagents were purchased from Sigma .Frozen left ventricle myocardium (∼200 mg) was homogenized in phosphate buffer (0.1 M) pH 7.4 and centrifuged at 12,000activity . Lipid hParaffin-embedded myocardial tissue was cut, mounted on slides for immunohistochemical analysis, and deparaffinized with EDTA for antigen retrieval , 54. Blog for 3 min, at 4 °C. The supernatant was transferred to another microtube and centrifuged at 18,000g for 10 min at 4 °C. The supernatant was then centrifuged at 100,000g for 45 min, at 4 °C. The supernatant was discarded and the pellet resuspended in 100 µL of lysis buffer [g for 10 min at 4 °C. The supernatant was analyzed by HPLC and the fluorescent DHE-derived products were quantified, as previously described [NADPH oxidase activity was evaluated in membrane-enriched cellular fraction by quantifying dihydroethidium (DHE) oxidation-derived fluorescent compounds, 2-hydroxyethidium (EOH) and ethidium, by HPLC according to a previously described method , 56. Carescribed , 56.Results are expressed as mean and standard deviation or median and 25th and 75th percentiles according to normal or non-normal distribution, respectively. Variables were compared by two-factor ANOVA followed by the Tukey test for normal distribution data or the Dunn test for non-normal distribution data. All rats were subjected to functional studies as their parameters usually present an elevated variability. In papillary muscle preparations, some animals were discarded due to technical problems. For all morphological and molecular analyzes, samples were randomly chosen. Statistical significance was accepted at p < 0.05.Initial and final body weight, heart rate, systolic blood pressure, and blood glucose are shown in Table At the beginning of the protocol, all echocardiographic variables were similar between groups (data not shown). Echocardiographic structural data assessed at the end of the protocol Table  showed hData from LV papillary muscle function at basal condition are shown in Table Myocyte diameter did not differ between groups Table . RegardiOxidative stress parameters are shown in Fig. In this study we evaluated the influence of anti-oxidant apocynin on cardiac remodeling in spontaneously hypertensive rats with type 1 diabetes mellitusSHR has extensively been used to evaluate long-term pressure overload-induced cardiac remodeling . At 1 moDiabetes was caused by streptozotocin, which has been widely used to induce type 1 diabetes mellitus in rodents –61. RatsIn this study, diabetic cardiomyopathy was characterized by left chambers dilation, LV mass increase, and diastolic dysfunction in SHR. Myocardial functional changes in SHR-DM included impaired systolic and diastolic function, characterized by a decreased maximum tension development rate and maximum tension decline rate and increased time to peak tension at basal contraction and after all positive inotropic stimulation. Similar structural and functional cardiac alterations have been described in normotensive and hypertensive diabetic rats , 69–71. As potential mechanisms involved in cardiac dilation and dysfunction, we observed that SHR-DM had increased oxidative stress, characterized by higher myocardial lipid hydroperoxide concentration, with altered activity of anti-oxidant enzymes glutathione peroxidase and catalase. SHR-DM also present higher myocardial fibrosis, as shown by the increased myocardial hydroxyproline concentration. Hydroxyproline is the main component of the collagen molecule and can only be found at small concentrations in a limited number of other proteins. Evaluation of myocardial fibrosis through hydroxyproline is considered more precise than histological analyses . MechaniApocynin administration did not change cardiac structures or function in control SHR. However, in papillary muscles, apocynin reduced developed tension at basal conditions and in post-rest contraction in SHR-APO compared to SHR. Despite lower glutathione peroxidase activity in SHR-APO, oxidative stress did not differ between SHR-APO and SHR. We can therefore conclude that apocynin impaired myocardial function independently of changes in oxidative stress. This result was unexpected as apocynin displayed beneficial effects in different experimental models of cardiac injury. In rodents with pressure overload induced by abdominal aorta banding  or angioIn diabetic SHR, apocynin reduced oxidative stress, evaluated by the myocardial lipid hydroperoxide concentration, and preserved anti-oxidant enzyme activity in SHR-DM-APO compared to SHR-DM. Despite the lower oxidative stress, LV and myocardial function was not changed by apocynin, except for a lower post-rest contraction −dT/dt in SHR-DM-APO than SHR-DM. Myocardial fibrosis did not differ from SHR-DM.Picrorhiza kurroa, and has been evaluated in experimental studies as an anti-oxidant agent [Apocynin can be isolated and purified from several plant species such as nt agent –84. It hnt agent , 82, 85.nt agent , 87 whicnt agent . Thus, ant agent . Apocynint agent . In vivont agent  and incrnt agent . AdditioIn conclusion, apocynin reduces oxidative stress through unrelated NADPH oxidase activity mechanisms and does not change ventricular or myocardial function in spontaneously hypertensive rats with type 1 diabetes. The apocynin-induced myocardial functional impairment in spontaneously hypertensive rats without diabetes shows that apocynin action during sustained chronic pressure overload needs to be clarified.


Regional myocardial scarring in adults following Tetralogy of Fallot (TOF) repair is associated with adverse clinical outcomes. This is the largest study to date assessing native T1 times as a marker for diffuse myocardial fibrosis in children after TOF repair. The aim of the study was to describe native T1 times patients post-TOF repair and to evaluate its relationship to clinical status and surgical factors.Mid-ventricular native T1 times using a modified look-locker inversion recovery (MOLLI) sequence were obtained in 80 consecutive children post-TOF repair, aged 13.1 ± 2.8 years, during routine cardiac magnetic resonance imaging (CMR). CMR results were compared to 28 controls and associations between native T1 times and echocardiographic, surgical and exercise factors were studied.Patients and controls were similar in age and gender distribution. Expectedly, TOF patients had significantly increased indexed right ventricular end-diastolic and end-systolic volumes and, as has been reported, significantly reduced right and left ventricular ejection fractions on CMR compared to controls. Increased right mid-ventricular native T1 times were found in cases compared to controls . There were no significant differences in the left mid-ventricular native T1 times between patients and controls. Primary repair bypass and cross-clamp times correlated with native T1 times of the left ventricular myocardium (r = 0.30 for bypass and 0.32 for cross clamp times), interventricular septum (r = 0.34 and 0.32 respectively), left ventricular free wall (r = 0.31 and 0.47 respectively) and right ventricle (r = 0.29 for cross clamp time). Weak negative correlations were observed between right ventricular native T1 times and right ventricular outflow tract gradient by echocardiography (r= -0.28), indexed left end-diastolic volume and stroke volume on CMR (r= -0.26 and -0.28 respectively). There was no correlation between native T1 times and the age or weight at primary repair, type of repair, QRS duration or peak predicted oxygen consumption or workload.Children following TOF repair have evidence of diffuse right ventricular myocardial fibrosis as demonstrated by higher mid-ventricular native T1 times compared to controls. Global left ventricular native T1 times are associated with longer aortic bypass and cross-clamp times at the time of primary repair. Clinical correlations with exercise capacity were not observed.


Right ventricular dysfunction (RVD) and enlargement (RVE) are increasingly associated with poor outcomes however their prevalence among patients with heart failure and those at risk has not been well characterized.or RVEDV/LVEDV exceeding mean plus 2 standard deviations of healthy gender matched controls. The prevalence of RV abnormalities and pattern of ventricular remodeling was compared among patient subgroups.Healthy controls and patients with heart failure related structural heart disease underwent a standard cardiac magnetic resonance examination. Right and left ventricular ejection fraction (EF) and end diastolic volumes (EDV) were traced from cine imaging. RVD was defined as RVEF less than mean minus 2 standard deviations of healthy gender matched controls. RVE was defined as either indexed RVEDV 2 for women and 71 ± 12 mL/m2 for men, p <0.05, and mean RVEDV/LVEDV was 0.94 ± 0.12 for women and 0.98 ± 0.14 for men, p = 0.19. Among patients, RVD was detected in 47%, RVE in 38% and either RV abnormality in 61%. RV abnormalities were common in all patient subgroups, ranging from 31% in hypertensive heart disease to 100% in right sided valvular heart disease.89 healthy controls, age 57 ± 10 years, and 502 patients, age 56 ± 16 years, were included. Among controls, RVEF was 61 ± 6% for women and 60 ± 5.6% for men, p = 0.5, indexed RVEDV was 63 ± 11 mL/mRV dysfunction and/or enlargement are prevalent among patients with heart failure related structural heart disease. Routine assessment is therefore recommended in 3-D cardiac imaging.


Cardiogenic shock is an acute emergency, which is classically managed by medical support with inotropes or vasopressors and frequently requires invasive ventilation. However, both catecholamines and ventilation are associated with a worse prognosis, and many patients deteriorate despite all efforts. Mechanical circulatory support is increasingly considered to allow for recovery or to bridge until making a decision or definite treatment. Of all devices, extracorporeal membrane oxygenation (ECMO) is the most widely used. Here we review features and strategical considerations for the use of ECMO in cardiogenic shock and cardiac arrest. Cardiogenic shock and cardiac arrest are life-threatening emergencies with a high mortality rate despite numerous efforts in diagnosis and therapy. For a long time medical therapy – at the forefront with catecholamines, vasodilators and others – and mechanical ventilation, if necessary, were the standard of care for cardiogenic shock. Oxygen supply and perfusion are critically reduced during shock and arrest, and both are physical processes that are in principle amenable to (temporary) extracorporeal mechanical support. Early pioneering work to prove this principle was performed in animals as early as 1937 , 3. WithIn the following, we review ECMO support in the context of cardiogenic shock and refractory cardiac arrest, with a special focus on technical aspects of veno-arterial ECMO. Of note, the following statements are primarily true for percutaneous ECMO with femoral cannulation and may not necessarily be directly transferable to central or upper-body cannulation.Cardiogenic shock is the main cause of early mortality in patients with acute myocardial infarction . Other cOut-of-hospital cardiac arrest (OHCA) occurs with an estimated incidence of 500,000 per year in Europe , 11, witThe majority of patients after OHCA develop post-cardiac arrest syndrome , 23 in aAs outlined, cardiogenic shock and cardiac arrest share many pathophysiological features and evoke many similar responses. Thus, it was not surprising but very important to prove that the prognosis of both conditions is equally adverse: In a recent study of 250 consecutive patients from Denmark, 130 were admitted to a tertiary center with cardiogenic shock, while 118 had OHCA. Interestingly, both groups had the same dismal outcome with 60% 1‑week mortality . This unFor many years catecholamines have been used for stabilization of patients with cardiogenic shock. Inotropes such as dobutamine are given with the intention to increase cardiac output by their positive inotropic and chronotropic function. In contrast, vasopressors such as norepinephrine are administered for increasing blood pressure by vasoconstriction and indirect effects such as increased preload. Epinephrine shares features of both drug classes. However, inotropic drugs increase myocardial oxygen consumption, heart rate, arrhythmogenicity, and inflammation in the already diseased heart . Beta1-aTherefore, it is increasingly being discussed to initiate mechanical circulatory support as a powerful tool for bridging earlier and more frequently, in order to improve the prognosis of patients with severe cardiogenic shock or refractory arrest . HoweverSeveral modes and devices of mechanical support are currently available , of whicThe intra-aortic balloon pump (IABP) consists of a catheter-mounted balloon that inflates during diastole and deflates during systole in the descending thoracic aorta. By this, coronary perfusion should be enhanced during diastole, while afterload should be decreased during systole when the left ventricle (LV) ejects. Notwithstanding the attractive pathophysiological principle, augmentation by IABP depends on LV output, and the potential of support decreases with lower LV output. Several studies have demonstrated that IABP support is not favorable in infarct-related cardiogenic shock , 34. TheThe TandemHeart® consists of a pump and two cannulas, of which one is inserted via venous access and transseptal approach into the left atrium (LA), and the other one via arterial access into the femoral artery. By this, the TandemHeart® introduces a right-to-left shunt, reduces LV preload by LA drainage, but increases afterload by retrograde flow support toward the aorta. The TandemHeart® is not widely used in Europe and requires experienced transseptal cannula placement, which is assumed to harbor considerable risk in the acute situation.Transaortic microaxial pumps  are introduced via arterial access through the aorta across the aortic valve into the LV. These devices directly unload the LV, transport the drained volume inside of the pump toward the aorta and eject into the aortic root. This elegant approach, which follows the physiological blood flow direction, is comprehensively described in the same issue of this journal . However, microaxial pumps do not offer gas exchange or temperature control.Probably, the most often used form of mechanical circulatory support today is ECMO. Originating from cardiac surgery and initially developed for temporary lung replacement, ECMO support is now broadly established for cardiorespiratory support . Notwithbridge-to-recovery approach. In the case of acute decompensated chronic heart failure, the potential for recovery may be limited, which sometimes results in a bridge-to-destination approach. In resuscitated patients, a bridge-to-decision strategy is usually required, as further therapies such as LVAD surgery, ICD implantation etc. are postponed until awakening of the patient allows for estimating neurological recovery and eligibility.In general, mechanical support can be used with different strategies Table . In patiECMO is a modified form of cardiopulmonary bypass , and hasIn contrast, veno-arterial (VA) ECMO drains blood from the right atrium and returns to the arterial system, typically to the iliac arteries toward the aorta Fig. . By thisA great advantage of VA-ECMO is that cannulation may be performed nearly everywhere, as the system and all parts are transportable. Thus, an unstable patient can receive ECMO support in the emergency room, on the ward, in the catheterization laboratory, the operating theater, or even in the field , 39. In VA-ECMO establishes a massive right-to-left shunt by draining venous blood and returning it to the iliac artery. This flow support, which can reach 7 l/min with large cannulas and contemporary rotors, results in a significant increase in blood pressure as long as there is enough vascular resistance (pressure = flow × resistance). The massive venous drainage effectively reduces preload and thus leads to venous decongestion. Arterial reinfusion to the systemic circulation strongly enhances perfusion of end organs and is therefore attractive during severe cardiorespiratory failure or resuscitation. Of note, at the same time retrograde flow support increases LV afterload (see next section).Notwithstanding the fast set-up of the system and the efficient hemodynamic support, VA-ECMO has contraindications and harbors a significant risk of complications Table . Most coECMO support is an invasive procedure with profound changes of body oxygenation and circulation, and inherently associated with potentially severe complications , 44. AmoThe retrograde ECMO output meets the antegrade LV output at a zone called the “watershed” , 45, 46.As outlined, circulation and oxygenation are overall subject to profound changes during VA-ECMO. Therefore multiple parameters have to be monitored in a patient on VA-ECMO at the same time  are sufficient to achieve decongestion. However, in many patients with lung failure on VA-ECMO support, the problem results from an ARDS-like condition, which cannot be or should not be effectively solved by aggressive ventilation or decongestion. In these patients an elegant and very effective treatment is upgrading the ECMO circuit to a triple-cannulated ECMO, with one venous-draining, one arterial-supplying, and one venous-supplying cannula  can be achieved by different methods. One way is venting through the atrial septum, either by atrioseptostomy , 61 or pThe frequency of the combined use of ECMO and Impella® varies greatly between centers. Of note, it is unclear to date which patients have a benefit of additional Impella® support in parallel to VA-ECMO. There are two published studies reporting combined support , 66. TheDespite the broad use of ECMO in experienced centers, data from larger studies are limited. Most studies are retrospective series or registry studies. Some years ago, IABP was used in many countries almost routinely for patients with severe cardiogenic shock, but later on randomized studies demonstrated the noneffectiveness of routine IABP support . With thFrom clinical experience, ECMO initiation is rather easy and fast, and ECMO is a very effective tool for enhancing and ensuring systemic circulation and provide gas exchange. As such, it should be primarily considered in patients with severe acute cardiorespiratory failure (the “crash and burn” patient). In addition, some specific indications exist, such as decompensated pulmonary arterial hypertension and pulmonary embolism. Table Assessment of ECMO in Acute Myocardial Infarction with Non-reversible Cardiogenic Shock to Halt Organ Failure and Reduce Mortality), which is currently investigating the use of ECMO in cardiogenic shock during myocardial infarction. In this context, an interesting tool that is already mentioned in current heart failure guidelines [From a pathophysiological perspective, VA-ECMO should be favored for bridge-to-destination or bridge-to-transplantation, when recovery is not the primary goal and LVAD or transplantation will follow. VA-ECMO is also favorable for bridge-to-surgery, especially for embolectomy. In resuscitated patients VA-ECMO is the commonly used device for bridge-to-decision. By contrast, VA-ECMO may not be the ideal support form for isolated LV dysfunction with potential for recovery , since afterload increases and recovery may be hampered . Of noteidelines  is the “idelines . Anotheridelines .Table Mechanical support is increasingly used in cardiogenic shock to minimize or avoid catecholamines and to facilitate regeneration of the diseased heart. Refractory cardiac arrest is an emerging indication for mechanical support, and recently more centers have developed ECPR programs. Cardiogenic shock and arrest share many pathophysiological features, and in this context VA-ECMO is a powerful extracorporeal life support system, as long as it is initiated early. VA-ECMO use requires a dedicated bridging strategy, such as bridge-to-recovery, bridge-to-decision, or bridge-to-destination, and complications need to be anticipated. Retrograde flow support increases LV afterload and may result in LV distension, which can be prevented and resolved by LV venting or active LV unloading. Prospective controlled studies are needed to develop specific protocols for defined clinical conditions, in order to find the optimal mechanical support strategy in a given situation.


We reviewed the patients’ medical records and identified patients with abnormal ultrasonic cardiogram and/or electrocardiogram (ECG). A total of 1462 patients  were identified to be treated for congenital upper limb malformation. Among them, 172 (11.8%) had abnormal ultrasonic cardiogram and/or ECG. Abnormal heart structure were discovered in 121 patients and 51 patients had abnormal ECG. The most common type of abnormal heart structure was tricuspid regurgitation , while the most common abnormal ECG was wave patterns . This hospital-based study suggests that the rate of congenital heart disease is high in patients treated for congenital upper extremity malformation in China. Surgeons and anesthetists should be aware of the comorbidity and preoperational examination of congenital heart diseases is highly needed to avoid complications during operation.Heart–hand syndrome (HHS) is a clinically and genetically heterogeneous disorder characterized by the co-occurrence of a congenital cardiac disease and an upper limb malformation. This study revealed the clinical and epidemiological features of HHS in China. The study was based on patients with congenital upper limb malformation treated in Beijing Ji Shui Tan hospital from October 1 The most common type of HHS is Holt–Oram syndrome (HOS) with an estimated incidence of 1/100 0002. The prevalence of HHS is low in Western countries, and an estimation of HHS rate in China is lacking until now. Because the mandatory policy of pre-marital medical check-up has stopped in China recently, an increased number of patients with congenital upper extremity malformation was noted as a consequence of the changed policy. We thus might expect that more HHS cases could be diagnosed soon in China5. Most congenital upper extremity malformations need surgical treatment. When congenital upper extremity malformation coexists with congenital heart disease, the complications might be higher during anesthesia and operation. It is thus highly necessary to explore the prevalence of HHS in patients with upper extremity malformation and to examine the strength to which it correlates with different upper limb malformation. The aims of this hospital-based study are (1) to estimate the prevalence of HHS among patients with a congenital limb malformation, (2) to analyze the characteristics and the clinical features of HHS in China.Heart–hand syndrome (HHS) is a clinically and genetically heterogeneous disorder characterized by the co-occurrence of a congenital cardiac disease and a limb malformationThis study was approved by the Ethics Committee at Beijing Ji Shui Tan Hospital. All methods were carried out in accordance with relevant guidelines and regulations, and informed consent was obtained from all subjects.st, 2013 and October 1st, 2016 were included in this study. We reviewed the medical records and checked the results of ultrasonic cardiogram and electrocardiogram (ECG). Patients with abnormal ultrasonic cardiogram and/or abnormal ECG were identified and met the criteria of clinical HHS. The clinical diagnostic criteria of HHS are congenital limb malformation combined with abnormal results of ultrasonic cardiogram or/and electrocardiogram. We further stratified upper extremity malformation according to Swanson upper extremity malformation classification .The datasets generated during and/or analysed during the current study are not publicly available due to the including of privacy information but are available from the corresponding author on reasonable request.st, 2013 and October 1st, 2016. Among them, 172 (11.8%) patients had abnormal ultrasonic cardiogram and/or ECG, and met the clinical diagnostic criteria of HHS. The prevalence of HHS was not significantly different between male and female  patients with congenital upper extremity malformations were identified and treated in Hand Surgery Department of Beijing Ji Shui Tan Hospital between October 16. Type I (19.4%) and type II (11.5%) congenital upper limb malformations were more likely to present with congenital cardiac disease. Among them, 121 (8%) patients showed an abnormal heart structure as discovered by ultrasonic cardiogram and 51 (3%) patients had only abnormal result of ECG. Patients who had both abnormal ultrasonic cardiogram and abnormal ECG were classified in the group of heart structural abnormalities, and a total of 46 (3%) had both abnormal ultrasonic cardiogram and ECG. The most common type of abnormal heart structure was tricuspid regurgitation . The most common abnormal result of ECG was abnormal wave patterns . There was significant difference in terms of prevalence of congenital heart defect among different types of upper limb malformation (p = 0.01).In Table The distribution of various congenital cardiac diseases among different type of upper limb malformations is shown in Table In this hospital-based study in China, we reviewed the medical records of a total of 1462 patients with congenital upper extremity malformations, and found that around 12% of them presented with congenital heart disease, which met the clinical diagnosis criteria of HHS. The prevalence of HHS was largely similar irrespective of gender, and the side of congenital limb malformations. However, the rate of and the type of congenital heart diseases varied by different types of upper limb malformations.7 in 1924. It has been reported by many others subsequently9. Several types of HHS have been identified of which Holt-Oram Syndrome (HOS) is the best known, which was reported by Holt and Oram10 in 1960 based on a four-generation familial study. The results of a European epidemiological study showed that HOS is a very rare condition with an average prevalence of 0.7 per 100,000 births and a high regional variation 12.HHS is well documented since first noted by Kato12, a clinical diagnosis of HOS should include the presence of preaxial radial ray malformation of at least one upper limb along with a personal or family history of septation defects  and/or atrioventricular conduction disease. A genetic testing for TBX5, 22q11.2, microdeletion and Fanconi anaemia might be needed for final diagnosis11. However, it is unfortunately not possible in the current study to do genetic testing of patients with congenital upper limb malformation and to retrieve their family history of septation defects  and/or atrioventricular conduction disease, as all of these patients were already discharged from the hospital without possibility to contact them, which might explain part of the discrepancy for the relatively low rate of HOS in the current study as compared with the literatures. Most of them (73%) could not be classified according to current classification.No epidemiological study was done for HHS so far. HHS is a broad category of diseases. The classification of HHS is shown in Supplementary Table 13. For patients with HOS, 14 patients involved left upper limbs and 20 patients involved right upper limbs. Bilateral involvement of upper limbs was noted in 12 patients, accounted for 26% of all HOS, which was lower than previous reports13. The prevalence of bilateral involvement was reported in 84% of patients with HOS, suggesting possible etiological difference between Chinese and Western population. In addition, it should be noted that most patients with HOS could be firstly treated in cardiac centers and therefore get lost in our study as we recruited only patients with congenital upper limb malformations, which might be the reason for the different rate and type of various congenital heart diseases as compared to the literatures.There was signification difference in term of the prevalence of congenital heart disease comorbid with different types of congenital upper limb malformations. According to Swanson classification of congenital upper limb malformations, the type I (Failure of formation of parts) and type II (Failure of differentiation) malformations were more likely to comorbid with congenital heart disease with a prevalence of 19.4% and 11.5%, respectively. Clinical doctors should be aware of these two types of congenital upper limb malformations. Pre-operational examination of the cardiovascular systems should be performed to avoid the risk of complications during operation. Thumb malformations, including radial polydactyly, radial ray deficiency, and thumb aplasia, were the most common malformations involved for HHS, accounted for 69.2% (119/172) of all HHS. This finding was in agreement with previous reports13, ASD was the most common cardiovascular anomaly, presenting in 53% of HOS patients, and VSD was noted in 48% of HOS patients. The involvement of different abnormal heart structure in HHS or HOS suggests that possible etiological differences between Chinese and Western population. Despite similarities of the clinical presentations of various HHS, it remains unclear whether the hereditary of HHS arises from common or distinct genetic defects. It has been suggested that congenital heart diseases are caused by a limited number of shared genetic defects17. However, some previous reports found that HHS are genetically heterogeneous with the possibility of arising from distinct disease genes20. We speculated that genes underlying the development of various Chinese HHS might be different as the morphological and anatomic sites were inconsistent with previous reports. Further studies are highly needed to examine the underlying mechanisms and to explore whether the contribution of distinct disease genes was consistent in Chinese and Western population.The most common type of abnormal heart structure was tricuspid regurgitation , while the most common abnormal result of ECG was abnormal wave patterns . For HOS, the most common abnormal heart structure was atrial septal defect (ASD) and/or ventricular septal defect (VSD) (13/46 28%), which was lower than previous report. In the study reported by Lindley B wallA few limitations should be kept in mind when we interpret the current findings. First, all the patients were identified from one hand clinic center, which might not be representative of the Chinese population. The second limitation was that this study was a retrospective epidemiological study and some individual information, such as family history of HHS which might be important to study HHS, was not available in the current study.In summary, the comorbidity of congenital upper extremity malformations and congenital heart disease is relatively high in China, and the rate and type of various congenital heart disease differ as compared to previous reports, suggesting possible etiological difference between Chinese and Western population. Preoperational examination should cover the field of congenital heart disease to avoid complications during operation.Supplementary tables


We hypothesized that longitudinal pulmonary arterial deformation during the cardiac cycle reflects pulmonary arterial capacitance. To examine this hypothesis, we assessed whether tissue Doppler-derived pulmonary annular motion could serve as a novel way to evaluate pulmonary arterial capacitance in pediatric patients with ventricular septal defect (VSD).n = 35) and age-matched healthy children . Pulmonary artery capacitance was calculated by two methods. Systolic pulmonary arterial capacitance (sPAC) was expressed as the stroke volume/pulmonary arterial pulse pressure. Diastolic pulmonary arterial capacitance (dPAC) was determined according to a two-element windkessel model of the pulmonary arterial diastolic pressure profile.In this prospective study, pulmonary annular velocity was measured in children  with a preoperative VSD  and diastolic e’ and a’ waves in all participants. The peak velocities of s1′, s2′, and e’ were significantly lower in the VSD group than in the Control group. On multiple regression analysis, sPAC was an independent variable affecting the peak velocities of the s1′, s2′, and e’ waves . The dPAC affected the s1′ wave peak velocity (β = 0.34). The time durations of the s1′ and e’ waves were independently determined by the sPAC (β = 0.49 and 0.27).Pulmonary annular motion velocity evaluated using tissue Doppler is a promising method of assessing pulmonary arterial capacitance in children with VSD.The online version of this article (doi:10.1186/s12947-016-0081-4) contains supplementary material, which is available to authorized users. Pulmonary vascular hemodynamic assessment has traditionally evaluated pulmonary vascular resistance (PVR) –3. HowevWe have previously reported that the pulmonary annular motion velocity waveform obtained using tissue Doppler imaging (TDI) reflects right ventricular outflow tract (RVOT) performance . In the The aim of this study, therefore, was to determine whether tissue Doppler-derived pulmonary annular motion velocity can be used as a noninvasive assessment of PA capacitance in children with ventricular septal defect (VSD).The prospective study group comprised consecutive 35 pediatric patients with a preoperative VSD . These patients were scheduled for surgical closure. Twenty-three age-matched healthy children without electrocardiographic or echocardiographic abnormalities  were also enrolled. The patients underwent cardiac catheterization within 3 days of assessment by echocardiography. Data collected between December 2012 and December 2015 were analyzed. All protocols were approved by the Institutional Review Board of the Tokushima University Hospital and conformed to the ethical guidelines of the Declaration of Helsinki (1975). The parents of all subjects provided their written, informed consent for their children to participate in the study.Standard and pulsed Doppler tissue echocardiography proceeded using a Preirus digital ultrasound system  equipped with 1–5 and 3–7 MHz sector transducers. All Doppler data were acquired from patients in the left lateral decubitus position during shallow respiration or end-expiratory apnea. Pulmonary annular motion velocity was measured using TDI in the long-axis view of the RVOT and PA. Guided by the two-dimensional images, a sample volume with a fixed length of 5.0 mm was placed on the pulmonary annulus of the RV free wall side, as indicated by the yellow arrow . FiguresIn addition to pulsed TDI, participants were assessed by conventional, two-dimensional, M-mode, pulsed, continuous, and color Doppler echocardiography. The left ventricular ejection fraction (LVEF) was calculated from apical two-chamber and four-chamber images using the biplane Simpson’s technique. All parameters were measured over three cardiac cycles and then averaged.2. PVR was calculated using the standard formula; that is, PVR was calculated as the mean PAP minus PA wedge pressure/pulmonary blood flow .All VSD patients underwent cardiac catheterization within 3 days of echocardiography. Catheterization and angiography using an Integris Allura 9 Biplane  proceeded using 4–6 Fr catheters. All patients were intubated and examined by biplane anteroposterior and lateral projection angiography. Ventricular volume was assessed by means of ventriculography and calculated using Simpson’s rule by quantitative CAW2000 cardiac analysis software . During cardiac catheterization, the main PA pressure was measured using a high-fidelity manometer-tipped 0.014-inch pressure wire  to compare with pulmonary annular motion velocity Fig. . Pulmona2) [2) was calculated from PVR and the PA time constant (tau) , which can be determined from measures of pulse pressure and stroke volume indexed to BSA. The sPAC was expressed as the stroke volume/pulse pressure  –8. Furth2) –12. Prevau) Fig. .U-test or Student’s t-test, as appropriate. Linear regression analyses were performed for correlations between the pulmonary annular motion velocity and hemodynamic parameters, and Pearson’s or Spearman’s correlation coefficients were calculated, as appropriate. Variables with p < 0.10 on univariate analysis were “candidates” for a backwards stepwise  multivariate analysis, and those with p < 0.05 were “retained” in the model. Multiple regression analysis was used to identify hemodynamic variables affecting the pulmonary annular motion waveform. All statistical data were calculated using Prism version 6.0  and JMP 11  installed on a desktop computer. A value of p < 0.05 was considered significant. Intra-observer and inter-observer reproducibilities of TDI measurements were assessed using Bland-Altman analysis in a blinded manner. Data were recorded and assessed at 5-minute intervals by observers 1 and 2 from 20 randomly selected participants . For intra-observer variability, data were analyzed twice, 8 weeks apart. Inter-observer variability was assessed by analyzing data from two separate observers blinded to each other’s results.All data are expressed as means ± standard deviation (S.D.) or as medians with the 5th–95th percentiles. Statistical significance was determined using the Mann-Whitney No subjects were excluded from the subsequent analyses due to suboptimal recording from poor echocardiographic imaging. Accordingly, the study group included 23 healthy children  and 35 VSD patients . Table 2, p < 0.0001). There was a significant correlation between these parameters .Figure p = 0.0070; 3.4 ± 0.7 vs. 4.1 ± 1.1 cm/s, p = 0.0107; 8.8 ± 2.3 vs. 13.0 ± 2.7 cm/s, p < 0.0001, respectively). The s1′ duration, s2′ duration, e’ duration, and a’ duration were significantly shorter in the VSD group , whereas isovolumic contraction time (ICT) and isovolumic relaxation time (IRT) were not significantly different between the two groups.Pulmonary annular motion was compared between the Control and VSD groups Fig. . The pear = 0.58, p = 0.0002). The s2′ and e’ velocity also showed significant correlations with the sPAC . ICT and IRT measured using TDI and the time duration of each wave were also assessed in terms of their correlations with the sPAC. The sPAC had significant correlations with s1′ and e’ and a’ wave duration , whereas there were no significant correlations with ICT, IRT, and s2′ wave duration. Figure r = 0.60, p = 0.0002; r = 0.46, p = 0.0051; r = 0.55, p = 0.0006; respectively). In regard to the timing issue, the e’ wave duration was significantly correlated with the dPAC .Next, the relationships between the parameters obtained from TDI-derived pulmonary and tricuspid annular motion and right heart performance were examined in the VSD group. Table p = 0.0131; β = 0.62, p <0.0001; β = 0.35, p = 0.0314; β = 0.49, p = 0.0029; and β = 0.27, p = 0.0488, respectively). The dPAC affected the s1′ wave peak velocity . The other right heart performance parameters, including RVEDP, RVSP, and Qp/Qs, also had an impact on pulmonary annular motion. Importantly, although RVEF had been assumed to determine pulmonary annular motion, no significant relationship was demonstrated with pulmonary annular motion in the VSD group.Next, multiple regression analysis for predictors of the pulmonary annular motion waveform was performed Table . The anan = 10; Control group, n = 10). Table The inter- and intra-observer reproducibilities of the TDI analysis of pulmonary annular motion were determined from Bland-Altman analysis of 20 randomly selected participants (VSD group, The present results showed that the pulmonary annular motion waveform is mainly determined by PA capacitance. Assessment of pulmonary annular motion is useful for estimating PA capacitance in children with VSD. Pulmonary annular TDI was found to be a simple, rapid, reproducible, and highly distinctive method for evaluating PA capacitance.Recent reports demonstrated that PA capacitance has great impact on the prognosis in various cardiac diseases –8. PatieTo the best of our knowledge, this is the first application of pulmonary annular motion velocity obtained by TDI as a tool for PA capacitance assessment. We postulated that the PA longitudinal deformation reflects stroke volume, and that the pulmonary annular motion waveform shows PA capacitance.In the present study, PA capacitance was represented by two parameters: sPAC and dPAC. There was a significant correlation between the two parameters, although sPAC was significantly higher than dPAC. The significant difference between the two parameters was assumed to be caused by the time phase difference during the cardiac cycle. The sPAC is the arterial capacitance from end-diastole to systole, whereas the dPAC is the capacitance from end-systole to diastole.The peak velocities of the pulmonary annular s1′, s2′, e’, and a’ waves were significantly lower in the VSD group than in the Control group (Fig. The present data demonstrated that pulmonary annular motion parameters can be used to represent PA capacitance. On multiple regression analysis, PA capacitance independently affected the pulmonary annular motion waveform and parameters. Importantly, RVEF was not an independent variable that determined pulmonary annular motion. This is likely due to the fact that PA stroke volume is not correlated with RVEF because VSD shunt flow is directly expelled to the PA during systole in the VSD group. The present data indicate that pulmonary annular motion is determined not by RV contraction, but by PA deformation in children with VSD. Nevertheless, the present study demonstrated the significant negative correlation between the pulmonary annular s1′ wave and RVEDP in the VSD group. Furthermore, RVSP and RVEDP affect the peak velocity of the e’ wave. It would be useful to investigate the relationship between pulmonary annular motion velocity and RV performance or RV overload. Further studies are necessary to determine the various factors affecting pulmonary annular motion.The sample cohort was relatively small, but TDI parameters were compared between patients and age-matched healthy individuals, and distinctive waveforms were found in the patient group. We postulated that PA expansion by the stroke volume and distensibility is similar in the radial and longitudinal directions. However, a directional difference might be present, which might generate systematic measurement error. The detailed characteristics of stiffness and elasticity in the PA radial and longitudinal directions should be elucidated in the future. Next, some degree of angulation between the Doppler beam and the true direction of longitudinal PA elasticity might exist. The long-axis view of the RVOT and PA was obtained, and the ultrasound beam was parallel to the direction of the pulmonary annular motions. We considered that this is the most appropriate cross-sectional view to observe the expansion and contraction of the PA.A significant correlation between the s1′ wave and RVEDP was found. Furthermore, RVSP and RVEDP had effects on the peak velocity of the e’ wave in the VSD group. These indicate that RV performance also affects pulmonary annular motion. It is necessary to note that PA capacitance is not the only factor determining pulmonary annular motion. From another point of view, it would be meaningful to investigate the relationship between pulmonary annular motion velocity and RV performance or RV overload. Further studies are needed to determine the utility of pulmonary annular motion.Lastly, although it was demonstrated that TDI-derived pulmonary annular motion parameters reflect PA capacitance, no attempt was made to determine the most useful parameter and derive the prediction formula to evaluate PA capacitance in the present study. The correlations found between pulmonary annular motion parameter and PA capacitance are relatively weak. Further studies of larger patient populations are needed to determine the most valuable parameter and the normal range of pulmonary annular motion for the evaluation of PA capacitance. Moreover, a further study with other disease populations would be necessary to establish the importance of the TDI-derived pulmonary annular motion waveform for the estimation of PA capacitance.Pulmonary annular TDI is a promising echocardiographic tool for evaluating PA capacitance in children with VSD. It can be a simple, rapid, reproducible, and highly distinctive method for evaluating PA capacitance.


Takotsubo syndrome (TS) is a transient form of left ventricular dysfunction associated with a distinctive contraction pattern in the absence of significant coronary artery disease triggered by stressful events. Several aspects of its clinical profile have been described but it still remains difficult to quickly establish the diagnosis at admission.Cardiovascular magnetic resonance (CMR) has achieved great improvements in the last years, which in turn has made this imaging technology more attractive in the diagnosis and evaluation of TS. With its superior tissue resolution and dynamic imaging capabilities, CMR is currently the most useful imaging technique in this setting.In this review, we propose to comprehensively define the role of CMR in the evaluation of patients with TS and to summarize a set of criteria suitable for diagnostic decision making in this clinical setting.The online version of this article (doi:10.1186/s12968-016-0279-5) contains supplementary material, which is available to authorized users. The defThe precise incidence of TS is unknown, but studies revealed a prevalence of 1–2 % of patients presenting with suspected acute coronary syndromes .The pathophysiological origin for this syndrome remains elusive and different etiologies are currently considered, with an excess of catecholamines precipitated by a situation of stress being of note. Activation of the sympathetic nervous system precipitates cardiac adrenergic stimulation and a subsequent change in contractility and electrophysiological status of the myocardium . SpecifiTS has generally been regarded as a relatively benign disease . HoweverAdvanced imaging modalities are becoming increasingly important in cardiovascular disease management, providing essential tools towards the diagnostic and prognostic work-up of patients with TS. Excluding significant coronary stenosis is part of its diagnostic algorithm. This evaluation is most often done invasively, as the patient usually presents with a clinical picture closely resembling that of acute myocardial infarction, but could be performed by coronary computed tomography angiography in selected cases.Cardiovascular magnetic resonance (CMR) has become a primary tool for non-invasive assessment of patients with TS Fig. , offerinIn this review we propose to explore the utility of CMR in the evaluation of patients with TS.During the recent decade, CMR has become the diagnostic tool of choice in tertiary care centers for patients with evidence of acute nonischemic myocardial injury. CMR has the unique ability to noninvasively demonstrate myocardial tissue injury through the presence of edema and/or delayed gadolinium contrast washout in myocardial extracellular matrix, providing distinctive insights into the pathogenesis and tissue pathology of several cardiac conditions.As experience and knowledge of TS has increased, the proposed Mayo diagnostic criteria for the syndrome have evolved . These cTable In a clinical setting for evaluation of TS, CMR appears as the one technique to provide a comprehensive assessment, including accurate and reproducible measurement of biventricular function and volumes, the possibility of serial evaluation, assessment of complications, myocardial perfusion and tissue characterization Table . CardiacSteady state free precession cines, phase contrast sequences, black-blood T2-W triple IR, first-pass perfusion, early gadolinium enhancement (EGE) and late gadolinium enhancement (LGE) sequences are the most widely used sequences in TS. Other CMR techniques such as T1 and T2 mapping techniques and feature/tissue tracking could be useful in the near future though at present limited to research purpose.A proposed standard CMR protocol in TS is depicted in Table takotsubo means ‘octopus pot’ in Japanese, as the LV assumes a similar shape. The ‘typical form’ presents with contraction abnormalities in the ventricular wall, equally affecting the anterior, inferior, and lateral walls, that extend beyond a single epicardial vascular territory. This ‘circumferential pattern’ can be considered a hallmark of TS [Cine sequences in CMR are a critical component in the diagnosis of TS and its variants. The word rk of TS . Anotherrk of TS , with mirk of TS . No diffrk of TS .Fig. 2TyAdditional file 1: Typical apical balloning in takotsubo syndrome. Cine CMR loops in 4- and 2-chamber view. (MOV 38365 kb)Additional file 2: Typical apical balloning in takotsubo syndrome. Cine CMR loop in short-axis all slices multiview. Upper panels-basal slices. Middle panels-middle slices. Lower panels-apical slices. According to the colour-scale, red represents the most positive radial strain and dark-blue represents the most negative radial strain. (MOV 3530 kb)Additional file 3: Mid-ventricular variant of takotsubo syndrome. Cine CMR loops in 4- and 2-chamber view. (MOV 21648 kb)These aspects can be associated with a systolic ventricular dysfunction, severe in some patients, producing clinical symptoms and signs of heart failure.Both basal hyperkinesis and mid-apical akinesis can produce a dynamic obstruction in the LV outflow tract associated or not with systolic anterior motion of the mitral leaflets and/or functional mitral valve regurgitation It is known that wall motion analysis with CMR has a pivotal role in clinical practice. At the present, image analysis is most commonly performed qualitatively. However, the diagnostic accuracy of qualitative assessment has been shown to be considerably operator dependant .Feature/tissue tracking CMR is a novel technique that allows quantification of motion and strain using standard steady-state free-precession cine sequences of routine ventricular morpho-functional protocol. So far, quantitative data on regional myocardial function in TS have been explored by echocardiography. Heggemann et al.  describeRegarding feature/tissue tracking CMR, further studies are undoubtedly needed to determine its role in both clinical and research environments  in 2-chamber view. (MOV 42270 kb)Additional file 6: 2-D radial strain analysis by multimodality tissue-tracking CMR  in short-axis all slices multiview). Upper panels-basal slices. Middle panels-middle slices. Lower panels-apical slices. According to the colour-scale, red represents the most positive radial strain and dark-blue represents the most negative radial strain. (MOV 55141 kb)Additional file 7: Cine CMR loop of 4-D radial strain analysis , depicting the typical apical balloning (blue) in a patient with takotsubo syndrome. (MOV 20707 kb)An important hallmark of inflammatory cell injury is the increased permeability of cellular membranes. Whereas initial membrane defects are of functional nature, leading to Na + influx and subsequent intracellular edema, a more severe injury allows for a net efflux of water and transmembranous leakage of larger molecules such as troponin, eventually leading to loss of cellular functions.Tissue T2 weighted (T2-W) imaging is a method that assesses magnetic image contrast, which is directly affected by the change in tissue water content, resulting in a high signal intensity of edematous tissue . Black-bIn TS one of the most characteristic finding is myocardial edema, a direct result of the injury process. It assumes a diffuse or transmural distribution in both apical and mid planes, a location that is not restricted to a particular vascular territory. Those areas of edema typically match the dysfunctional ventricular contraction area observed with cine CMR sequences, which are usually globally circumferential, but restricted to a portion of the LV, such as involving all segments of apical portion, or alternatively mid or basal portions Figs.  and 10.FThese features can be used to differentiate TS from acute myocardial infarction, in which edema usually has a coronary distribution on the LV wall.In acute myocarditis patients, T2-W triple IR sequence shows high signal intensity often with a multifocal and heterogeneous distribution in regions with LGE, that could be transmural, but frequently with higher signal intensity on mid-wall or subepicardial myocardial layer.Another indicator of the inflammatory processes in TS is the slight association between edema and pericardial effusion  Figs. 11 and 12.Initial T2 hyperintensity reduces over the following weeks, whereas T2 hyperintensity of segments affected by myocardial infarct is maintained for more than 2 or 3 months after symptom onset , 22.To note, even though T2-W triple IR is normally used in CMR to detect edema, some authors have suggested the use of T2 mapping technique to diagnose it, which seems to be more insensitive to motion artifacts .Despite increasing evidence on the use of T2-W triple IR, it is a recognized motion and blood pool artifact prone sequence. Parametric mapping techniques, especially T2 mapping, are emerging as a more robust alternative for edema appreciation and quantification in diverse clinical scenarios. Future research exploring the role of T2 mapping in TS is required.In most cases, LV segments show no perfusion defects and findings on these techniques are usually normal in patients with TS. However, in some patients CMR first-pass perfusion studies may appear normal at basal segments but demonstrate subendocardial perfusion defects, especially more apically . AccordiEGE sequence, ideally performed within 2 min after contrast agent infusion, is optimal for identification of adherent endocardial thrombus on mid-apical segments with severe hypokinesis or akinesis. Thrombus is recognized as a low signal intensity (no gadolinium uptake), nearly black, that makes contrast with the intermediate signal of myocardium and blood pool, when de inversion time of the IR gradient echo sequence is set to 500–550 ms.In some cases, LV thrombus can be detected by cine CMR Fig. , althougLGE depends on differences in the volume of distribution of gadolinium in normal and pathologically altered myocardium  and seveIn general, LGE indicates the relative changes of the extracellular and intracellular volumes. Therefore, any changes to the interstitium, such as edema or fibrosis, increase the volume of distribution causing LGE . FurtherThe absence of LGE in TS patients as documented by CMR studies has been described in many cases and is a common diagnostic criterion in most CMR centers. However, several studies challenged this notion by reporting delayed hyperenhancement in TS patients , 29 Fig. Rolf etNotwithstanding with this, a pathophysiological explanation for LGE in TS has been investigated. It is known that the level of extracellular matrix proteins is elevated and the amount of collagen-1 and fibronectin is significantly raised in the phase of severe contractile impairment, followed by normalization in functional recovery phase . In the Differently, Sacha et al.  and Marép = 0,049) and longer time to normalize electro and echocardiographic changes. They also reported a positive correlation between the LGE area ratio  in the sub-acute phase (2–7 days after presentation) and the duration to normalization of both ECG  and echocardiogram .Some authors investigated the clinical implications of LGE (using different thresholds) in TS. Eitel et al.  showed nThe utility of LGE is undeniable in the setting of focal myocardial fibrosis and necrosis, where different signal intensity threshold methods are used to detect enhancement. However, when myocardial injury is subtler and there are no confidently recognizable reference regions of normal myocardium, fibrosis may go undetected on conventional LGE threshold methods. In contrast, T1 mapping sequences provide a different approach to tissue characterization, permitting the measure of the intrinsic relaxation times of myocardium pre and post gadolinium infusion, not dependent on relative signal intensities. Therefore, it has the potential to improve the sensitivity of CMR tissue characterization, especially when diffuse and subtle fibrosis is the possible mechanism, like in TS.An important issue that has recently been seen with the use of CMR and its cine sequences is a significant percentage of patients (up to one-third) with right ventricular involvement, which in turn was associated with longer hospitalization, worse markers of heart failure, particularly pleural effusion Fig.  and oldeCardiovascular complications associated to TS are listed in Table A complete clinical follow-up including CMR and/or echocardiography for confirmation of LV function recovery should be available 3–6 months after presentation . Since the underlying pathophysiology of TS is believed to be a form of myocardial stunning, recovery of normal systolic function is important to confidently make the diagnosis Fig. . DespiteAdditional file 8: Follow-up CMR of the Fig. Diagnosis of TS has important implications for clinical management at presentation and afterward. CMR provides incremental information and allows the detection of relevant functional and tissue changes useful for the diagnostic work up of TS. The combination of typical regional wall motion abnormalities and presence of reversible myocardial injury may be helpful in differentiation of TS from other etiologies in overlapping clinical presentations.


A long standing axiom in the field of teratology states that the teratogenic period, when most birth defects are produced, occurs during the third to eighth weeks of development post-fertilization. Any insults prior to this time are thought to result in a slowing of embryonic growth from which the conceptus recovers or death of the embryo followed by spontaneous abortion. However, new insights into embryonic development during the first two weeks, including formation of the anterior-posterior, dorsal-ventral, and left-right axes, suggests that signaling pathways regulating these processes are prime targets for genetic and toxic insults. Establishment of the left-right  axis is particularly sensitive to disruption at very early stages of development and these perturbations result in a wide variety of congenital malformations, especially heart defects. Thus, the time for teratogenic insults resulting in birth defects should be reset to include the first two weeks of development. According to the principles of teratology, as defined by a founding father of that science, James Wilson, embryos begin to be susceptible to a teratogenic insult, “toward the end of the germ layer stage [when] specific organ differentiation begins” . Thus, “Recent evidence challenges this basic tenet and demonstrates that establishment of the body axes, dorso-ventral (D-V), cranio-caudal , and left-right  is essential for normal development. It is generally agreed that the first axes to form are the A-P and D-V axes. At the latest these axes are specified in the peri-implantation period soon after the blastocyst forms at approximately days 4–5 of development ,3,4 and The role of laterality signaling in normal and abnormal development has been particularly well characterized and a variety of structural birth defects involving almost every tissue and organ system has been observed when establishment of the L-R axis is disrupted  8,9,10,,12,13. TPITX2, a “master gene” for left sided development [PITX2 results in laterality defects especially of the heart [Toxic insults and/or alterations of gene expression can interfere with any of these steps from the breaking of symmetry to organ development, thereby resulting in a congenital malformation. One of the key periods in the process of establishing L-R asymmetry occurs late in the second week and early in the third week of gestation at the primitive streak stage of development when gene expression patterns important for establishing the left side are occurring . At thiselopment ,16. Thathe heart ,18,19,20nodal on that side by signaling through the histone deacetylase binding partner Mad3, As a result, the concentration of nodal increases on the left side of the primitive node triggering the laterality pathway, on the left [Xenopus embryos [How nodal becomes restricted to the left is not clear, but evidence suggests that the neurotransmitter serotonin (5-HT) is a key signaling molecule. According to this theory, 5-HT accumulates on the right side of the embryo and represses expression of the left ,21,22,23 embryos .Exposure of embryos to teratogens during this early period of development also results in laterality defects, including heart malformations. For example, exposure of rat embryos at the primitive streak stage to X-irradiation resulted in some embryos with situs inversus and others with heterotaxy, and some of these had heart malformations . A similsitus solitus. Complete reversal of all organs, where organs are reversed in a mirror image arrangement, is called situs inversus. Discordant organ positioning with respect to symmetry, where one or more organs are abnormally positioned  or if isomerisms or inversions are present, is called situs ambiguus or heterotaxy. Individuals with situs inversus and situs ambiguus are considered to have “laterality” defects [Although a wide variety of birth defects can be observed in individuals with abnormal patterns of laterality, both animal and clinical studies indicate that the most commonly affected organ is the heart. Exactly when heart development is affected is not clear, but one critical period occurs late in the second and early in the third week at primitive streak stages when heart cells are being patterned ,27,28. N defects  and thes defects  and thei defects ,31,32. I defects ,11,12,31 defects ,33,34. I defects ,15,33.Thus, the most sensitive organ to be affected by abnormal L-R patterning is the heart. Virtually every type of heart defect can be observed where there is perturbation in L-R patterning signals, even in the absence of defects to other organs. Thus, l and d transpositions of the great arteries (TGAs), dextrocardia, ventricular inversions and isomerisms, atrial inversions and isomerisms, and many other congenital cardiac defects result from abnormal signaling in the laterality pathway . ,43. 42,4As more is learned about signaling that regulates axis patterning, it is becoming clearer that birth defects related to abnormalities in this signaling can probably be induced even earlier than the primitive streak stages described above. Evidence for this claim can be found in patients with midline abnormalities, including neural tube defects, cleft lip and palate, omphalocele, anal atresia, and stenosis, and caudal dysgenesis that occur when laterality signaling is disrupted ,15,31,41