Recurrent Ventricular Tachycardia in a Young Adult-Imaging and Genetic Evidence of DSP-Associated Arrhythmogenic Cardiomyopathy: A Case Report.

Abstract

Background: Ventricular tachycardia (VT) may represent the first manifestation of inherited cardiomyopathies, particularly in young patients without overt structural heart disease. Arrhythmogenic cardiomyopathy (ACM) is an inherited myocardial disorder characterized by ventricular arrhythmias, fibrofatty myocardial replacement, and an increased risk of sudden cardiac death. Pathogenic variants in the desmoplakin (DSP) gene have been increasingly associated with left-dominant or biventricular forms of ACM and inflammatory "hot phases" of myocardial injury.

Case presentation: We report the case of a 37-year-old male presenting with sustained monomorphic VT with right ventricular outflow tract morphology requiring synchronized electrical cardioversion. Electrocardiography in sinus rhythm demonstrated low-voltage limb leads and T-wave inversion in V1-V3. Echocardiography showed mildly reduced right ventricular function with dyskinesia of the RV free wall (TAPSE 17 mm, RV S ^' 10 cm/s). Cardiac magnetic resonance revealed mild RV dilation and subepicardial late gadolinium enhancement in the lateral left ventricular wall with mild pericardial involvement, consistent with an ACM-related inflammatory phenotype. An implantable cardioverter defibrillator was implanted for secondary prevention. Genetic testing identified a heterozygous pathogenic DSP frameshift variant (c.1009_1010dup; p.Leu338Serfs36∗), confirming the diagnosis of DSP-related ACM.

Conclusion: This case highlights the importance of integrating electrocardiography, multimodality imaging, and genetic testing in the evaluation of VT in young adults. Identification of a pathogenic DSP variant confirmed the diagnosis of ACM and has important implications for arrhythmic risk stratification and family screening.