CONGRESS ABSTRACT

Background Dilated cardiomyopathy is a heterogeneous disease with multiple etiologies and variable clinical expression. Among inherited forms, specific genetic variants are considered high risk due to their association with increased mortality, heart failure progression, and ventricular arrhythmias. However, limited data are available in patients with advanced heart failure, and the hemodynamic expression of different genotypes remains poorly defined. Objectives To investigate hemodynamic characteristics and prognostic implications of different genetic variants in patients with dilated cardiomyopathy and advanced heart failure. Methods We conducted a single-center retrospective observational study including patients with advanced heart failure due to non-ischemic dilated cardiomyopathy referred for advanced therapy screening. Only patients undergoing genetic testing were included. Ischemic heart disease and end-stage valvular, hypertrophic, infiltrative, and congenital cardiomyopathies were excluded. Clinical, laboratory, echocardiographic, and invasive hemodynamic data obtained by right heart catheterization were collected. The primary endpoint was a composite of death, arrhythmic storm, or urgent heart transplantation. Results Twenty-nine patients were enrolled; 13 had a high-risk genotype (HRG+) and 16 a non–high-risk genotype (HRG−). Mean age was 47±12 years and 41% were female; 28% carried an LMNA mutation. HRG+ patients showed lower TAPSE (14.5±3.7 vs 17.5±3.5 mm, p=0.032). At right heart catheterization, HRG+ patients had lower pulmonary vascular resistance (1.99±0.75 vs 2.94±1.06 Wood units, p=0.009) and a trend toward higher pulmonary arterial compliance (3.83±1.98 vs 2.73±0.82 mL/mmHg, p=0.079). PAPi values were lower in HRG+ patients without reaching statistical significance. High-risk genotypes were associated with worse outcomes for the primary endpoint (46.0% vs 19.1%, p=0.018). Conclusions In patients with dilated cardiomyopathy and advanced heart failure, high-risk genotypes were associated with poorer prognosis. Echocardiography and right heart catheterization suggest impaired right ventricular function as a potential pathophysiological mechanism. Larger prospective studies are needed.