Hypertrophic cardiomyopathy (HCM) is a relatively common genetic cardiac disorder. The prevalence of HCM in the general population is estimated to be approximately 1 in 500 individuals, or 0.2 %, which translates to at least 600,000 affected individuals in the United States [[1], [2], [3], [4]]. Cardiac arrest (CA) is a significant concern due to the arrhythmogenic potential of HCM. The annual incidence of sudden cardiac death (SCD) in HCM patients is approximately 1 %, with higher rates observed in adolescents and young adults [5].

Implantable cardioverter defibrillators (ICD) have been shown to be highly effective in terminating life-threatening arrhythmias and improving survival in this population [6,7]. Placement of an ICD for primary prevention of SCD in HCM patients is recommended for adult patients with HCM who have one or more major risk factors for SCD [8], including a family history of SCD, massive left ventricular (LV) hypertrophy with a LV wall thickness of 30 mm or greater, unexplained syncope, LV apical aneurysm, and LV systolic dysfunction with an ejection fraction less than 50 % [8]. Minor risk factors for SCD in HCM patients include atrial fibrillation (AF), myocardial ischemia, left ventricular outflow tract obstruction, and high-risk genetic mutations [9,10]. While these minor risk factors are associated with an increased risk of SCD, they do not independently necessitate the placement of an ICD [9,10].

This study aims to investigate the association between electrocardiographic abnormalities and the risk of CA in patients hospitalized with HCM. By analyzing a large cohort of patients, we sought to identify the relationship of atrioventricular (AV) blocks, bundle branch blocks (BBB), supraventricular arrhythmias, and premature ventricular contractions (PVCs) to CA. Understanding these relationships may identify previously unrecognized risk factors for CA in HCM patients.