Robert Hättasch

Shear-wave Amplitudes Measured with Cardiac MR Elastography for Diagnosis of Diastolic Dysfunction

PURPOSE To test whether shear-wave amplitudes (SWAs) in the myocardium measured with cardiac magnetic resonance (MR) elastography enable diagnosis of myocardial relaxation abnormalities in patients with diastolic dysfunction. MATERIALS AND METHODS Each subject gave written informed consent to participate in this institutional review board-approved prospective study. Electrocardiographically triggered SWA-based cardiac MR elastography with 24.13-Hz external vibration frequency was performed in 50 subjects grouped into asymptomatic young (n = 10, 18-39 years) and asymptomatic old (n = 10, 40-68 years) subjects and patients with echocardiographically proved mild, moderate, or severe diastolic dysfunction (n = 30, 44-73 years). SWA images were analyzed in the left ventricular (LV) region and were normalized against reference SWA of the thoracic wall. Analysis of variance with Bonferroni-corrected pairwise comparison and Pearson correlation were used for statistical evaluation. RESULTS Young and old control subjects had normalized mean LV SWA of 0.67 ± 0.04 (standard error of the mean) and 0.56 ± 0.04 (P = .18, F test), respectively. Compared with the control groups, patients with mild, moderate, and severe diastolic dysfunction displayed significantly reduced normalized mean LV SWA of 0.37 ± 0.04, 0.34 ± 0.04, and 0.29 ± 0.04 (P < .001, F test), respectively, which was inversely correlated to the severity of diastolic dysfunction (R = -0.61, P < .001). The best cutoff value to differentiate between asymptomatic volunteers and patients was 0.43, yielding an area under the receiver operating characteristic curve of 0.92, with 90% sensitivity and 89.7% specificity. CONCLUSION LV SWA measured with cardiac MR elastography provides image contrast sensitive to myocardial relaxation abnormalities and shows significantly lower values in patients with diastolic dysfunction.

Exercise-induced changes of left ventricular diastolic function in postmenopausal amateur marathon runners: assessment by echocardiography and cardiac biomarkers

Purpose Diastolic dysfunction is common among elderly women. Recently, concerns regarding marathon-induced myocardial damage were raised among young male runners. The goal of our study was to assess the impact of marathon running on systolic and diastolic ventricular function before and immediately after completing a marathon among postmenopausal well-trained amateur women. Methods A total of 89 female runners of the Berlin Marathon were included (35 postmenopausal and 54 premenopausal female controls) and examined before, immediately, and 2 weeks after the race by echocardiography (including tissue Doppler- and 2D strain speckle tracking) and underwent blood tests. Results After the marathon, there was a significant increase in E/E′ (postmenopausal 8.5 ± 2.3 vs. 10.9 ± 3.2 post race; control: 8.1 ± 1.8 vs. 9.9 ± 2.9 post race, p < 0.001) and a decrease in E/A in both groups (postmenopausal 1.3 ± 0.36 vs. 0.9 ± 0.21 post race; control 1.7 ± 0.6 vs. 1.1 ± 0.3; p < 0.001). In contrast, regardless of the hormonal status the atrial contraction increased significantly. Left and right ventricular systolic contractility, as assessed by speckle tracking and pulsed-wave tissue Doppler velocities, showed a significant increase in both groups. Of all runners, 55 (61.8%) experienced increases in troponin T and/or N-terminal-B-type natriuretic peptide after the race. All echocardiographic and laboratory parameters returned to normal within 2 weeks. Conclusions 2D strain analysis of the left and right ventricles showed an acute improvement of the systolic function after marathon running in pre- and postmenopausal well-trained women. There were no long lasting detrimental effects on the diastolic function.

Isovolumetric Elasticity Alteration in the Human Heart Detected by In Vivo Time-Harmonic Elastography

Time harmonic elastography (THE) has recently been introduced for measurement of the periodic alteration in myocardial shear modulus based on externally induced low-frequency acoustic vibrations produced by a loudspeaker. In this study, we propose further developments of cardiac THE toward a clinical modality including integration of the vibration source into the patient bed and automated parameter extraction from harmonic shear wave amplitudes, wall motion profiles and synchronized electrocardiographic records. This method has enabled us to evaluate the delay between wall motion and wave amplitude alteration for the measurement of isovolumetric times of elasticity alteration during contraction (τ(C)) and relaxation (τ(R)) in a group of 32 healthy volunteers. On average, the wave amplitudes changed between systole and diastole by a factor of 1.7 ± 0.3, with a τ(C) of 137 ± 61 ms and a τ(R) of 68 ± 73 ms, which agrees with results obtained with the more time-consuming and expensive cardiac magnetic resonance elastography. Furthermore, because of the high sampling rate, elasto-morphometric parameters such as transition times and the area of wave amplitude-cardiac motion cycles can be processed in an automated way for the future clinical detection of myocardial relaxation abnormalities.

Galectin-3 increase in endurance athletes

Background Galectin-3 is a new and promising biomarker for heart failure and myocardial fibrosis. Although endurance exercise is a crucial element in cardiovascular disease prevention, the relationship between exercise and plasma levels of galectin-3 is still unknown. To date, the relationship between regular exercise and myocardial fibrosis is not fully understood. This study investigates the relationship between endurance exercise and plasma levels of galectin-3. Methods Twenty-one male, healthy non-elite marathon runners were examined before and within 1 hour after a strenuous run of 30 km after 4-day training abstinence. Examination included blood samples for galectin-3, echocardiography, and cardiac magnetic resonance imaging (CMR). In addition, to distinguish between cardiac or skeletal muscular origin of galectin-3, 27 C57Bl/6 J mice performing voluntary wheel running and 25 sedentary mice were analysed. Results Plasma galectin-3 in endurance athletes increased from baseline to post exercise (12.8 ± 3.4 ng/ml to 19.9 ± 3.9 ng/ml, p < 0.001) while the systolic left and right ventricular function remained unchanged. Interestingly, baseline plasma levels of galectin-3 were in normal range but higher than in healthy sedentary controls. However, in CMR there was no correlation between baseline galectin-3 levels and the detection of myocardial fibrosis. In animal studies, the relative level of mRNA for galectin-3 in active mice was significantly higher compared to sedentary mice. This increase was most pronounced in skeletal muscle (98.0% higher, p < 0.001) and not in the myocardium of the left ventricle (19.9% higher, p = 0.043). Conclusions Plasma galectin-3 is substantially elevated in endurance athletes after running but does not correlate with cardiac function, other biomarkers, or myocardial fibrosis. In mice, we demonstrate that galectin-3 increase during endurance exercise originates primarily from skeletal muscle.

Time-Resolved Analysis of Left Ventricular Shear Wave Amplitudes in Cardiac Elastography for the Diagnosis of Diastolic Dysfunction.

ObjectivesThe aim of this study was to investigate the diagnostic potential of changes in left ventricular (LV) shear wave amplitudes (SWAs) over the cardiac cycle measured by cardiac magnetic resonance elastography. Materials and MethodsElectrocardiography-triggered SWA-based cardiac magnetic resonance elastography with 24.13-Hz external vibration frequency was performed in asymptomatic young (n = 10) and old (n = 10) subjects and patients (n = 30) with echocardiographically proven mild, moderate, or severe diastolic dysfunction. The temporal delay between change in SWA and morphological change in the LV wall, that is, time of isovolumetric elasticity relaxation normalized against heart rate, was calculated for diastole (&tgr;R0). Diastolic levels of LV SWA were calculated and normalized against SWA in the chest wall (U0[dia]). Nonparametric testing was used for statistical evaluation. Accuracy of the parameters was investigated using receiver operating characteristic analysis against echocardiography. Interobserver and intraobserver variability for the temporal delay between change in SWA and morphological changes was tested according to Bland and Altman. ResultsYoung and old control subjects showed median (standard error of mean, interquartile range) &tgr;R0 of 99 (5, 93–103) and 82 (7, 66–95). In patients with diastolic dysfunction, &tgr;R0 was 131 (20, 107–171), 158 (14, 108–172), and 138 (14, 107–174) with statistically significant differences between old subjects and patients with diastolic dysfunction (P = 0.01). U0(dia) was 0.94 (0.05, 0.86–1.04) and 0.71 (0.06, 0.61–0.92) in young and old controls, respectively (P = 0.063). Compared with young subjects, patients with mild, moderate, and severe diastolic dysfunction displayed significantly reduced U0(dia) of 0.69 (0.06, 0.53–0.82), 0.56 (0.04, 0.46–0.64), and 0.48 (0.04, 0.43–0.61) (P < 0.001). &tgr;R0/U0(dia) cutoff values for prediction of diastolic dysfunction were 107/0.66, corresponding to the area under the receiver operating characteristic values of 0.84/0.87 with 74%/74% sensitivity and 85%/85% specificity. Interobserver and intraobserver variability ranged from −0.05 to 0.05 with 95% agreement. ConclusionsIn diastolic dysfunction, low-frequency SWAs show distinct changes in the normalized time of isovolumetric elasticity relaxation for the LV (&tgr;R0) and the diastolic level of SWA (U0[dia]). Both parameters have good diagnostic performance for diagnosis of diastolic dysfunction.

Normative reference data, determinants, and clinical implications of right atrial reservoir function in women assessed by 2D speckle-tracking echocardiography

We aim to determine normative reference data of phasic right atrial (RA) strain and to investigate determinants, possible clinical implications as well as feasibility and reproducibility of RA strain analysis.

Percutaneous biventricular Impella support in therapy-refractory cardiogenic shock

Introduction: Percutaneous mechanical circulatory support systems have increasingly been adopted as a bail out strategy in patients with cardiogenic shock. Since studies showed mostly mixed results, however, the use of support systems remains a case by case decision. Case: Here, we report on a case of therapy‐refractory cardiogenic shock due to acute myocardial infarction treated with percutaneous right and left ventricular assist devices (Impella RP and CP). Conclusion: Due to myocardial stunning, even patients with fulminant cardiogenic shock have the potential for full recovery. In the present case, we demonstrate the feasibility of biventricular Impella support in therapy‐refractory cardiogenic shock facilitating bridge to recovery.