Aims Hypokinetic nondilated cardiomyopathy (HNDC) is defined by left ventricular dysfunction without significant dilatation. The distinct features and prognosis of HNDC compared to classical dilated cardiomyopathy (DCM) are partially unexplored. We investigated the differences between HNDC and DCM cohorts from the multicentric Italian IN-HF registry. Methods All patients with a diagnosis of DCM enrolled in the registry between 2008 and 2023 were considered. HNDC was defined by a left ventricular end-diastolic diameter of less than 34 mm/m 2 in men and less than 31 mm/m 2 in women, or a left ventricular end-diastolic volume of 70 ml/m 2 or less in men and less than 60 ml/m 2 in women. The primary outcome was a composite of all-cause death and heart failure hospitalizations (HFHs). Results Of 1748 patients, 568 (32.5%) met the criteria for HNDC. HNDC patients were more likely to be male, with a higher prevalence of obesity and atrial fibrillation. HNDC also showed less advanced disease (less advanced New York Association class, higher left ventricular ejection fraction, lower prevalence of moderate-severe mitral regurgitation, and less atrial dilatation). After a median follow-up of 13 months, the primary outcome occurred less frequently in HNDC compared with DCM 12.5 vs. 17.1%; hazard ratio 0.762, 95% confidence interval (95% CI) 0.581–0.999; P = 0.049. However, the adjusted prognosis was similar between groups (hazard ratio 1.031, 95% CI 0.771–1.380; P = 0.834). Beta-blockers emerged as the most protective drug for HNDC (hazard ratio 0.462, 95% CI 0.258–0.826; P = 0.009). Conclusion HNDC appears as a distinct form of DCM with milder clinical presentation. However, the absence of LV dilation did not independently influence prognosis. Beta-blockers may offer the most consistent benefit in HNDC.
Manca et al. (Mon,) studied this question.