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Aims Myocardial oxygenation is impaired in hypertrophic cardiomyopathy (HCM) patients with left ventricular hypertrophy (LVH), and possibly also in HCM gene carriers without LVH. Whether these oxygenation changes are also associated with abnormalities in diastolic function or left ventricular (LV) strain are unknown. Methods and results We evaluated 60 subjects: 20 MYBPC3 gene positive patients with LVH (G+LVH+), 18 MYBPC3 gene positive without LVH (G+LVH−), 11 gene negative siblings (G−), and 11 normal controls (NC). All subjects underwent 2D transthoracic echocardiography and cardiovascular magnetic resonance imaging for assessment of ventricular volumes, mass, and myocardial oxygenation at rest and adenosine stress using the blood oxygen level dependent (BOLD) technique. Maximal septal thickness was 20 mm in the G+LVH+ group, vs. 9 mm for the G+LVH− group. As expected, the G+LVH+ group had a more blunted myocardial oxygenation response to stress when compared with the G+LVH− group (−5% ± 3% vs. 2% ± 4%, P Conclusion Myocardial deoxygenation during stress is observed in MYBPC3 HCM patients, even in the presence of normal LV diastolic function, LV global longitudinal strain, and LV wall thickness.

Background: Anthracycline (A) and trastuzumab (T) chemotherapy have well-recognized cardiac toxicity, potentially leading to significant morbidity and mortality. Our previous work in 46 prospectively enrolled breast cancer patients showed early left ventricular (LV) and right ventricular (RV) function decline at 1 and 3 months, but only persistent RV dysfunction at 12 months which correlated with myocardial oedema observed early (1 and 3 months) after administration of chemotherapy regimes. Method: To investigate late cardiac effects, the same cohort were re-imaged with advanced Cardiovascular Magnetic Resonance (CMR) imaging including T1 mapping 5 ± 1 year post chemotherapy. Results: Twenty-six out of 46 (50%) patients underwent follow-up imaging. A statistical but non-clinically significant decrease was observed in LV ejection fraction (EF) from baseline to 5 years (72.2 ± 6.6 to 65.4 ± 9.3, p < 0.005). Subjects with initial drop of LVEF by > 10% at 3 months (n = 5) or at 12 months (n = 3) did not demonstrate any difference in LV or RVEF at 5 years. No correlation was observed between myocardial oedema and LV or RVEF at 5 years. At 5 years, T1 values were within normal limits overall (935 ± 48 ms). One patients had significantly elevated ( > 1000 ms) T1 values with no correlation to LV or RVEF. No subjects demonstrated replacement myocardial fibrosis at 5 years. Conclusion: Using advanced CMR, contemporary chemotherapy regimes demonstrate minimal long-term cardiac toxicity. There is minimal diffuse and no replacement fibrosis as demonstrated by LGE, following chemotherapy. This study suggests limiting serial imaging in these patients at 12 months post chemotherapy. Refereed/Peer-reviewed

Background Coronary artery disease and left ventricular hypertrophy are prevalent in the chronic kidney disease ( CKD ) and renal transplant ( RT ) population. Advances in cardiovascular magnetic resonance ( CMR ) with blood oxygen level–dependent ( BOLD ) technique provides capability to assess myocardial oxygenation as a measure of ischemia. We hypothesized that the myocardial oxygenation response to stress would be impaired in CKD and RT patients. Methods and Results Fifty‐three subjects (23 subjects with CKD , 10 RT recipients, 10 hypertensive ( HT ) controls, and 10 normal controls without known coronary artery disease) underwent CMR scanning. All groups had cine and BOLD CMR at 3 T. The RT and HT groups also had late gadolinium CMR to assess infarction/replacement fibrosis. The CKD group underwent 2‐dimensional echocardiography strain to assess fibrosis. Myocardial oxygenation was measured at rest and under stress with adenosine (140 μg/kg per minute) using BOLD signal intensity. A total of 2898 myocardial segments (1200 segments in CKD patients, 552 segments in RT , 480 segments in HT , and 666 segments in normal controls) were compared using linear mixed modeling. Diabetes mellitus ( P =0.47) and hypertension ( P =0.57) were similar between CKD , RT , and HT groups. The mean BOLD signal intensity change was significantly lower in the CKD and RT groups compared to HT controls and normal controls (−0.89±10.63% in CKD versus 5.66±7.87% in RT versus 15.54±9.58% in HT controls versus 16.19±11.11% in normal controls, P BOLD signal intensity change was associated with estimated glomerular filtration rate (β=0.16, 95% CI =0.10 to 0.22, P CKD predialysis, RT , and HT groups. None of the CKD patients had impaired global longitudinal strain and none of the RT group had late gadolinium hyperenhancement. Conclusions Myocardial oxygenation response to stress is impaired in CKD patients and RT recipients without known coronary artery disease, and unlikely to be solely accounted for by the presence of diabetes mellitus, left ventricular hypertrophy, or myocardial scarring. The impaired myocardial oxygenation in CKD patients may be associated with declining renal function. Noncontrast BOLD CMR is a promising tool for detecting myocardial ischemia in the CKD population.

Purpose: Right ventricular (RV) systolic function as measured by right ventricular ejection fraction (RVEF) has long been recognized as an important predictor of outcome in heart failure patients. The echocardiographic measurement of RV volumes and RVEF is challenging, however, owing to the unique geometry of the right ventricle. Several nonvolumetric echocardiographic indices of RV function have demonstrated prognostic value in heart failure. Comparison studies of these techniques with each other using RVEF as a benchmark are limited, however. Furthermore, the contribution of these various elements of RV function to patient functional status is uncertain. We therefore aimed to: (1) Determine which nonvolumetric echocardiographic index correlates best with RVEF as determined by cardiac magnetic resonance (CMR) imaging (the accepted gold standard measure of RV systolic function) and (2) Ascertain which echocardiographic index best predicts functional capacity. Methods: Eighty-three subjects (66 with systolic heart failure and 17 healthy controls) underwent CMR, 2D echocardiography, and cardiopulmonary exercise testing for comparison of echocardiographic indices of RV function with CMR RVEF, 6-minute walk distance and VO 2 PEAK . Results: Speckle tracking strain RV strain exhibited the closest association with CMR RV ejection fraction. Indices of RV function demonstrated weak correlation with 6-minute walk distance, but basal RV strain rate by tissue velocity imaging had good correlation with VO 2 PEAK . Conclusion: Strain by speckle tracking echocardiography and strain rate by tissue velocity imaging may offer complementary information in the evaluation of RV contractility and its functional effects. Refereed/Peer-reviewed