Profile of Rhythm Disturbances and Predictive Factors of Sudden Death in Sarcomeric Hypertrophic Cardiomyopathy: A Retrospective Study of 30 Patients

Abstract

Introduction: Sarcomeric hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease. Its prognosis is primarily determined by the risk of ventricular arrhythmias and sudden cardiac death (SCD). This study aimed to describe the rhythm profile of patients with sarcomeric HCM, to identify clinical and paraclinical predictors of arrhythmias, and to assess the risk of SCD using the European Society of Cardiology (ESC) risk stratification score. Materials and Methods: This retrospective descriptive study included 30 patients with sarcomeric HCM followed in an electrophysiology department between July 2021 and December 2025. All included patients underwent a complete clinical examination, a surface electrocardiogram (ECG), a 24- to 48-hour Holter ECG recording, a transthoracic echocardiogram, and, for 20 of them, cardiac magnetic resonance (CMR) imaging. The 5-year risk of SCD was calculated using the ESC online risk score. Results: The mean age of the patients was 46 ± 29 years, with a male-to-female ratio of 2.7. Atrial fibrillation (AF) was the most frequent arrhythmia, affecting 20% of patients (16% of whom presented with a paroxysmal form). Premature ventricular contractions (PVCs) were observed in 90% of patients on Holter monitoring, while only one patient (3.3%) presented with non-sustained ventricular tachycardia (NSVT). Regarding the SCD risk score, 73% of patients were classified as low risk (<4%), 10% as intermediate risk (4–6%), and 17% as high risk (≥6%). Five patients underwent implantable cardioverter-defibrillator (ICD) implantation for primary prevention. Notably, no thromboembolic complications or deaths were recorded during the 4-year follow-up period. Conclusion: In our series, atrial fibrillation was the most frequent arrhythmia in patients with sarcomeric HCM. The ESC 2014 score proved to be an effective tool for stratifying the risk of SCD. ICD implantation in high-risk patients was well tolerated and may improve prognosis.