Background LGE by CMR is a predictor of adverse cardiovascular outcomes in non-ischemic cardiomyopathy (NICM) patients. However, these findings are limited by single center studies, small sample sizes, and low event rates. We performed a meta-analysis to evaluate the prognostic role of late-gadolinium enhancement by cardiac magnetic resonance (LGE-CMR) imaging in NICM patients. Methods and Results PubMed, Cochrane CENTRAL and EMBASE were searched for studies looking at the prognostic value of LGE-CMR in NICM patients. The primary end-points included all-cause mortality, heart failure hospitalization (HFH), and a composite end point of sudden cardiac death (SCD) or aborted SCD. Pooling of odds ratios (OR) was performed using a random-effect model and annualized event rates (AER) were assessed. Data was included from 9 studies with a total of 1,488 patients and a mean follow-up of 30 months. Patients had a mean age of 52 years, 67% were male and the average LVEF was 37% on CMR. LGE was present in 38% of patients. Patients with LGE had increased overall mortality (OR 3.27, p<0.00001), HFH (OR 2.91, p=0.02), and SCD/aborted SCD (OR 5.32, p<0.00001) when compared with those without LGE. The AERs for mortality were 4.7% for LGE+ subjects vs. 1.7% for LGE- subjects (p=0.01), 5.03% vs. 1.8% for HFH (p=0.002), and 6.0% vs. 1.2% for SCD/aborted SCD (p<0.001). Conclusions LGE in NICM patients is associated with increased risk of all-cause mortality, HFH, and SCD. Detection of LGE by CMR has excellent prognostic characteristics and may help guide risk stratification and management in NICM patients.

Objectives To assess the relationship between extracellular volume (ECV), native T1, and systolic strain in hypertensive patients with left ventricular hypertrophy (HTN LVH), hypertensive patients without LVH (HTN Non-LVH) and normotensive controls. Background Diffuse myocardial fibrosis in HTN LVH patients, as reflected by increased ECV and native T1, may be an underlying mechanism contributing to increased cardiovascular risk when compared to HTN Non-LVH subjects and controls. Furthermore increased diffuse fibrosis in HTN LVH subjects may be associated with reduced peak systolic and early diastolic strain rate when compared to the other two groups. Methods T1 mapping was performed in 20 HTN LVH (55±11 years), 23 HTN Non-LVH (61±12) and 22 control (54±7) subjects on a Siemens 1.5T Avanto using a previously validated MOLLI pulse sequence. T1 was measured pre-contrast and 10, 15 and 20 minutes following injection of 0.15 mmol/kg Gd-DTPA, and the mean ECV and native T1 were determined for each subject. Measurement of circumferential strain parameters were performed using cine displacement encoding with stimulated echoes (DENSE). Results HTN LVH subjects had higher native T1 when compared to controls (p < 0.05). HTN LVH subjects had higher ECV when compared to HTN Non-LVH subjects and controls (p < 0.05). Peak systolic circumferential strain and early diastolic strain rate were reduced in HTN LVH subjects when compared to HTN Non-LVH subjects and controls (p < 0.05). Increased levels of ECV and Native T1 were associated with reduced peak systolic and early diastolic circumferential strain rate across all subjects. Conclusions HTN LVH patients had higher ECV, longer native T1 and associated reduction in peak systolic circumferential strain and early diastolic strain rate when compared to HTN Non-LVH and control subjects. Measurement of ECV and native T1 provide a non-invasive assessment of diffuse fibrosis in hypertensive heart disease.

Objectives Using cardiac magnetic resonance (CMR), we sought to evaluate the relative influences of mechanical, electrical, and scar properties at the left ventricular (LV) lead position (LVLP) on CRT response and clinical events. Background CMR cine displacement encoding with stimulated echoes (DENSE) provides high quality strain for overall dyssynchrony (circumferential uniformity ratio estimate [CURE, 0–1]) and timing of onset of circumferential contraction at the LVLP. CMR DENSE, late gadolinium enhancement, and electrical timing together could improve upon other imaging modalities for evaluating the optimal LVLP. Methods Patients had complete CMR studies and echocardiography before CRT. CRT response was defined as a 15% reduction in LV end-systolic volume. Electrical activation was assessed as the time from QRS-onset-to-LVLP-electrogram (QLV). Patients were then followed for clinical events. Results In 75 patients, multivariable logistic modeling accurately identified the 40 (53%) of patients with CRT response (AUC=0.95 [p<0.0001]) based on CURE (OR 2.59/0.1 decrease), delayed circumferential contraction onset at LVLP (OR 6.55), absent LVLP scar (OR 14.9), and QLV (OR 1.31/10 ms increase). The 33% of patients with CURE<0.70, absence of LVLP scar, and delayed LVLP contraction onset had a 100% response rate, whereas those with CURE≥0.70 had a 0% CRT response rate and a 12-fold increased risk of death, and the remaining patients had a mixed response profile. Conclusions Mechanical, electrical, and scar properties at the LVLP together with CMR mechanical dyssynchrony are strongly associated with echocardiographic CRT response and clinical events after CRT. Modeling these findings holds promise for improving CRT outcomes.

BackgroundPreliminary semi-quantitative cardiovascular magnetic resonance (CMR) perfusion studies have demonstrated reduced myocardial perfusion reserve (MPR) in patients with angina and risk factors for microvascular disease (MVD), however fully quantitative CMR has not been studied. The purpose of this study is to evaluate whether fully quantitative CMR identifies reduced MPR in this population, and to investigate the relationship between epicardial atherosclerosis, left ventricular hypertrophy (LVH), extracellular volume (ECV), and perfusion.MethodsForty-six patients with typical angina and risk factors for MVD (females, or males with diabetes or metabolic syndrome) who had no obstructive coronary artery disease by coronary angiography and 20 healthy control subjects underwent regadenoson stress CMR perfusion imaging using a dual-sequence quantitative spiral pulse sequence to quantify MPR. Subjects also underwent T1 mapping to quantify ECV, and computed tomographic (CT) coronary calcium scoring to assess atherosclerosis burden.ResultsIn patients with risk factors for MVD, both MPR (2.21 [1.95,2.69] vs. 2.93 [2.763.19], p < 0.001) and stress myocardial perfusion (2.65 ± 0.62 ml/min/g, vs. 3.17 ± 0.49 ml/min/g p < 0.002) were reduced as compared to controls. These differences remained after adjusting for age, left ventricular (LV) mass, body mass index (BMI), and gender. There were no differences in native T1 or ECV between subjects and controls.ConclusionsStress myocardial perfusion and MPR as measured by fully quantitative CMR perfusion imaging are reduced in subjects with risk factors for MVD with no obstructive CAD as compared to healthy controls. Neither myocardial hypertrophy nor fibrosis accounts for these differences.Electronic supplementary materialThe online version of this article (10.1186/s12968-018-0435-1) contains supplementary material, which is available to authorized users.