Prognostic value of atrial strain measured by CMR in hypertrophic cardiomyopathy

Abstract Introduction and Objectives Hypertrophic cardiomyopathy (HCM) increases the risk of major adverse cardiovascular events (MACE). However, current predictive models are imperfect. Left atrial global longitudinal strain (LA-GLS), assessed by cardiac magnetic resonance (CMR), may enhance cardiovascular risk stratification. This study aimed to evaluate the prognostic value of CMR-derived LA-GLS in predicting MACE in a cohort of patients with HCM. Methods This was a retrospective, longitudinal, single-center study including 282 patients with HCM who underwent CMR. LA-GLS was assessed using feature-tracking. The primary endpoint (MACE) was a composite of ventricular arrhythmias (including sudden cardiac death, sustained and non-sustained ventricular tachycardia, and appropriate ICD discharge), heart failure (hospitalization, transplant, or ventricular assist device), and cardiovascular mortality. Results The mean age was 56.8 ± 17.3 years, and 42.9% were women. The maximum wall thickness (MWT) was 17.3 ± 4.3 mm, late gadolinium enhancement (LGE) was present in 140 patients (51.1%), and LA-GLS was 27.4 ± 14.4%. Genetic testing was positive in 96 patients (49.2%). During a median follow-up of 6.5 years (interquartile range: 3.4–8.5 years), 71 patients (25%) experienced MACE, including 4 sudden cardiac deaths, 12 poorly tolerated sustained ventricular tachycardias, 6 ICD discharges, 26 hospitalizations for heart failure, 2 transplants, 1 ventricular assist device, and 8 cardiovascular deaths. Table 1 shows the CMR variables according to the occurrence of MACE. In multivariate analysis, adjusted for MWT, indexed myocardial mass, and indexed left ventricular end-systolic volume, the variables independently associated with MACE were LVEF (HR 0.95, 95% CI 0.91–0.99, p = 0.046), LA-GLS below the median value (27.8%) (HR 1.83, 95% CI 1.07–3.14, p = 0.028; Figure 1A), and LGE >5% of total myocardial mass (HR 2.82, 95% CI 1.59–5.03, p < 0.001). This model demonstrated good predictive value, with an area under the curve of 0.72 (95% CI 0.65–0.79) (Figure 1B). Conclusions Atrial strain measured by CMR is associated with increased risk of cardiovascular events in HCM beyond established prognostic variables. Our CMR-based predictive model showed good discriminant value. Integrating atrial strain assessment into clinical practice may optimize patient management.