Arrythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and cathecholaminergic polymorphic ventricular tachycardia (CPVT): A phenotypic spectrum seen in same patient

- ARVD/C and CPVT, rare inheritable sudden cardiac death syndromes, result from mutation in different genes but recently, mutation in a common gene RYR2 has been associated with both disorder.
- It has even been suggested that CPVT and ARVD/C represent a phenotypic spectrum.
- Our patient is unique in expressing both the phenotypes of ARVD/C and CPVT in the absence of RYR2 gene mutation or other gene mutations known to cause CPVT and ARVD/C; possibly our patient has novel disease causing mutation that has yet been unidentified
- Our patient had sudden cardiac death and required an ICD regardless of the etiology as there was no reversible cause found. The discovery of CPVT gave more importance to beta-blocker up-titration and the addition of flecainide
- Hence, it is important to actively monitor the phenotype in patients with inheritable sudden cardiac death syndromes as it has an implication on their management and also in screening their relatives

ARVD/C and CPVT are rare inheritable sudden cardiac death syndromes predominantly expressed in younger individuals. ARVD/C is characterized by a progressive fibrofatty replacement of the myocardium that predisposes to ventricular tachycardia while CPVT is characterized by exercise induced bidirectional/polymorphic ventricular tachycardia (VT) and a structurally normal heart. A mutation in different genes causes these syndromes but recently, mutation in a common gene RYR2 has been associated with both disorders and it has been suggested that CPVT and ARVD/C represent a phenotypic spectrum. We present a case unique in expressing both these phenotypes.