Electrical storm in hypertrophic cardiomyopathy: Cardiac magnetic resonance and sudden cardiac death risk stratification: a case report

Risk stratification for sudden cardiac death (SCD) is a key factor in the management of patients with hypertrophic cardiomyopathy (HCM). Cardiac magnetic resonance (CMR) has a unique role in the evaluation of HCM and offers superior diagnostic and prognostic information to assess the indication for a prophylactic implantable cardioverter-defibrillator (ICD).

A 39-year-old patient with non-obstructive HCM with a low ESC HCM Risk-SCD score underwent a CMR revealing a left ventricular apical aneurysm and extensive late gadolinium enhancement; a prophylactic ICD was thus implanted. A month later, the patient was admitted in refractory electrical storm with over 50 appropriate ICD shocks due to sustained ventricular tachycardia. Despite anti-arrhythmic therapy and mechanical ventilation, the evolution was unfavourable with haemodynamic instability; veno-arterial extracorporeal membrane oxygenation was implanted. The patient was submitted to CMR-guided epicardial VT catheter ablation with complications of LV thrombus and severe pericardial effusion.

This case details the complex risk stratification for SCD in patients with HCM, highlighting the important role of CMR in the integrated approach to risk stratification.