Implantable cardioverter-defibrillator implantation should be considered in high-risk patients with apical hypertrophic cardiomyopathy as the same manner with the septal type

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: Apical hypertrophic cardiomyopathy (HCM) is considered to have a benign prognosis in terms of cardiovascular mortality. Sudden cardiac arrest and ventricular fibrillation (VF) in patients with apical HCM is rarely reported. METHODS: Between July 2001 and May 2021, 96 HCM patients who had undergone implantable cardioverter-defibrillator (ICD) implantation from three tertiary hospitals were reviewed. We evaluated the prevalence of aborted sudden cardiac death and/or documented VF in apical HCM and known risk markers for sudden cardiac death in those populations. RESULT: Fifteen patients (15.6%) were apical HCM in total population. Among apical HCM, seven patients (40.0%) presented with aborted sudden cardiac death or documented VF, therefore received ICD implantation for the secondary prevention. All seven patients had at least one risk marker suggested either 2020 ACC/AHA guideline or 2014 ESC guideline. One patient had three risk factors and two patients had two risk factors and four patients had one risk factor. Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR), personal history of unexplained syncope and non-sustained ventricular tachycardia (VT) were the common risk factors. CONCLUSIONS: Clinical outcomes in patients with apical HCM are not always as benign as previously thought. ICD implantation should be considered in high-risk patients with apical HCM as the same manner with the septal type of HCM according to the current guideline recommendations.