Late gadolinium enhancement distribution patterns in non-ischemic dilated cardiomyopathy: Genotype-phenotype correlation.

AIMS Late gadolinium enhancement (LGE) is frequently found in patients with dilated cardiomyopathy (DCM), there is little information about its frequency and distribution pattern according to underlying genetic substrate. We sought to describe LGE patterns according to genotype and to analyze the risk of major ventricular arrhythmias (MVA) according to patterns. METHODS AND RESULTS Cardiac magnetic resonance findings and LGE distribution according to genetics was performed in a cohort of 600 DCM patients followed at 20 Spanish centers. After exclusion of individuals with multiple causative gene variants or with variants in infrequent DCM-causing genes, 577 patients (34% females, mean age 53.5 years, LVEF 36.9 ± 13.9%) conformed the final cohort. A causative genetic variant was identified in 219 (38%) patients and 147 (25.5%) had LGE. Significant differences were found comparing LGE patterns between genes (P < 0.001). LGE was absent or rare in patients with variants in TNNT2, RBM20 and MYH7 (0%, 5% and 20%, respectively). Patients with variants in DMD, DSP and FLNC showed predominance of LGE subepicardial pattern (50%, 41% and 18%, respectively) whereas patients with variants in TTN, BAG3, LMNA and MYBPC3 showed unspecific LGE patterns. Genetic yield differed according to LGE pattern. Patients with subepicardial, lineal midwall, transmural, right ventricular insertion points or with combination of LGE patterns showed increased risk of MVA compared with patients without LGE. CONCLUSION LGE patterns in DCM has a specific distribution according to the affected gene. Certain LGE patterns are associated with increased risk of MVA and with increased yield of genetic testing.This study has been funded by Instituto Salud Carlos III (ISCIII) through the projects ‘PI18/0004, PI19/01283, and PI20/0320’ (co-funded by the European Regional Development Fund/European Social Fund ‘A way to make Europe’/‘Investing in your future’). The Hospital Universitario Puerta de Hierro, the Hospital Universitario Vall Hebrón, the Hospital General Universitario Gregorio Marañón, and the Hospital Universitario Virgen de la Arrixaca are members of the European Reference Network for Rare, Low Prevalence, and Complex Diseases of the Heart (ERN GUARD-Heart). F.d.F. receives grant support from ISCIII (CM20/00101). R.B. receives funding from the Obra Social la Caixa Foundation. M.B. receives funding from ISCIII (PI19/01283). The CNIC is supported by the ISCIII, Ministerio de Ciencia e Innovación of the Spanish Government (MCIN), and Pro CNIC Foundation.S

Three-Dimensional Morphology of the Left Ventricular Outflow Tract: Impact on Grading Aortic Stenosis Severity.

BACKGROUND: Left ventricular outflow tract (LVOT) measurement is a critical step in the quantification of aortic valve area. The assumption of a circular morphology of the LVOT may induce some errors. The aim of this study was to assess the three-dimensional (3D) morphology of the LVOT and its impact on grading aortic stenosis severity. METHODS: Fifty-eight patients with aortic stenosis were studied retrospectively. LVOT dimensions were measured using 3D transesophageal echocardiography at three levels: at the hinge points (HP) of the aortic valve and at 4 and 8 mm proximal to the annular plane. Results were compared with standard two-dimensional echocardiographic measurements. RESULTS: Three-dimensional transesophageal echocardiography showed a funnel shape that was more circular at the HP and more elliptical at 4 and 8 mm proximal to the annular plane (circularity index = 0.92 vs 0.83 vs 0.76, P < .001). Cross-sectional area was smaller at the HP and larger at 4 and 8 mm from the annular plane (3.6 vs 3.9 vs 4.1 cm2, P = .001). The best correlation between two-dimensional and 3D transesophageal echocardiographic dimensions was at the HP (intraclass correlation coefficient = 0.75; 95% CI, 0.59-0.86). When the HP approach was selected, there was a reduction in the percentage of patients with low flow (from 41% to 29%). CONCLUSIONS: A large portion of patients with aortic stenosis have funnel-shaped and elliptical LVOTs, a morphology that is more pronounced in the region farther from the annular plane. Two-dimensional LVOT measurement closer to the annular plane has the best correlation with 3D measurements. Measurement of the LVOT closer to the annular plane should be encouraged to reduce measurement errors

Combination of late gadolinium enhancement and genotype improves prediction of prognosis in non-ischaemic dilated cardiomyopathy

Aims: Genotype and left ventricular scar on cardiac magnetic resonance (CMR) are increasingly recognized as risk markers for adverse outcomes in non-ischaemic dilated cardiomyopathy (DCM). We investigated the combined influence of genotype and late gadolinium enhancement (LGE) in assessing prognosis in a large cohort of patients with DCM. Methods and results: Outcomes of 600 patients with DCM (53.3 ± 14.1 years, 66% male) who underwent clinical CMR and genetic testing were retrospectively analysed. The primary endpoints were end-stage heart failure (ESHF) and malignant ventricular arrhythmias (MVA). During a median follow-up of 2.7 years (interquartile range 1.3–4.9), 24 (4.00%) and 48 (8.00%) patients had ESHF and MVA, respectively. In total, 242 (40.3%) patients had pathogenic/likely pathogenic variants (positive genotype) and 151 (25.2%) had LGE. In survival analysis, positive LGE was associated with MVA and ESHF (both, p < 0.001) while positive genotype was associated with ESHF (p = 0.034) but not with MVA (p = 0.102). Classification of patients according to genotype (G+/G−) and LGE presence (L+/L−) revealed progressively increasing events across L−/G−, L−/G+, L+/G− and L+/G+ groups and resulted in optimized MVA and ESHF prediction (p < 0.001 and p = 0.001, respectively). Hazard ratios for MVA and ESHF in patients with either L+ or G+ compared with those with L−/G− were 4.71 (95% confidence interval: 2.11–10.50, p < 0.001) and 7.92 (95% confidence interval: 1.86–33.78, p < 0.001), respectively. Conclusion: Classification of patients with DCM according to genotype and LGE improves MVA and ESHF prediction. Scar assessment with CMR and genotyping should be considered to select patients for primary prevention implantable cardioverter-defibrillator placementThis work was supported by grants from the Instituto de Salud Carlos III (ISCIII) (PI18/0004, PI19/01283, PI20/0320). (Co-funded by European Regional Development Fund/European Social Fund ‘A way to make Europe’/‘Investing in your future’). The Hospital Universitario Puerta de Hierro Majadahonda, the Hospital Clinic, the Hospital Vall d’Hebron, the Hospital General Universitario Gregorio Marañón and the Hospital Universitario Virgen de la Arrixaca are members of the European Reference Network for rare, low-prevalence, and complex diseases of the heart (ERN GUARD-Heart). The CNIC is supported by the ISCIII, MCIN, the Pro-CNIC Foundation, and the Severo Ochoa Centers of Excellence program (CEX2020-001041-S). Conflict of interest: none declare