Integrated role of cardiac magnetic resonance and genetics in predicting left ventricular reverse remodelling in dilated and non-dilated cardiomyopathy

Aims: Left ventricular reverse remodelling (LVRR) is a prognostic marker in patients with dilated (DCM) and non-dilated left ventricular cardiomyopathy (NDLVC). The utility of combining late gadolinium enhancement (LGE) and genetic testing in predicting LVRR in DCM/NDLVC remains a knowledge gap. This study aimed to assess an integrated approach including LGE data and genetics to predict LVRR in DCM/NDLVC patients. Methods and results: This multicentre observational study included DCM/NDLVC patients with: (i) baseline echocardiographic left ventricular ejection fraction (LVEF) <50%; (ii) genetic testing; (iii) baseline cardiac magnetic resonance (CMR); (iv) 12-month follow-up echocardiographic data. LVRR was defined as LVEF increase ≥10% or LVEF ≥50% (if baseline LVEF <45%) at 12 months. Outcome measures were: (i) all-cause mortality, heart transplant, or left ventricular assist device implantation (D/HT/LVAD); (ii) sudden cardiac death or major ventricular arrhythmias (SCD/MVA). Arrhythmogenic genes studied were LMNA, DSP, FLNC, and RBM20. Among 1757 DCM/NDLVC with genetic data, 616 met eligibility (462 DCM, 154 NDLVC; age 51 ± 14 years, 34% female). LVRR occurred in 314 patients (51%): 251 (54%) in DCM and 63 (41%) in NDLVC (p = 0.004). Independent predictors of LVRR within 1 year included titin truncating variants, absence of arrhythmogenic genes, and absence of LGE ring-like pattern. In patients with LVEF <35%, only the presence of LGE ring-like pattern and arrhythmogenic genes remained independently related to a lower rate of LVRR and increased SCD/MVA risk. Conclusion: In a large genetically and CMR characterized DCM/NDLVC cohort, arrhythmogenic genotypes and LGE ring-like pattern were inversely related to LVRR, particularly in patients with LVEF <35%.