Abstract
Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is a rare inherited cardiomyopathy marked by fibrofatty replacement of right ventricular (RV) myocardium, leading to electrical instability and increased risk for ventricular arrhythmias and sudden cardiac death (SCD). ARVC is typically inherited in an autosomal dominant pattern and often involves mutations in desmosomal proteins such as plakophilin-2 (PKP2). Clinical presentation can vary from asymptomatic to life-threatening arrhythmias, particularly among young athletes. This case emphasizes the importance of early detection and intervention in patients with ARVC. A 21-year-old previously healthy male presented with recurrent exertional syncope. Initial ECG demonstrated sinus rhythm with T-wave inversions in leads V1-V3. Coronary CT angiography and resting echocardiography were normal. However, the stress electrocardiogram revealed frequent premature ventricular complexes (PVCs) with a left bundle branch block morphology. Ambulatory event monitoring detected over 500 monomorphic PVCs in a 24-hour period. Cardiac MRI demonstrated mildly reduced RVEF (39%) with regional dyskinesia, meeting major diagnostic criteria per the 2010 Task Force Criteria for ARVC. Genetic testing confirmed a heterozygous pathogenic mutation (c.1689-1G>C) in the PKP2 gene. The patient was started on beta-blockers and underwent implantation of a single-chamber implantable cardioverter defibrillator (ICD) due to elevated arrhythmic risk. Post-implantation, the ICD successfully terminated three episodes of ventricular tachycardia, highlighting its life-saving role. This case underscores the necessity for a high index of suspicion when evaluating young patients with unexplained syncope or arrhythmias. Diagnosis of ARVC requires integration of clinical, electrocardiographic, imaging, and genetic data. Early diagnosis and prompt management, including activity modification, pharmacologic therapy, and ICD implantation, are critical to mitigating the risk of SCD. Genetic testing and vigilant follow-up remain essential components in the care of ARVC patients.