Background:
ARVC is a rare inherited disorder usually affecting the right ventricle,
characterized by fibro-fatty tissue substitution of healthy ventricular
myocardium. It often predisposes young patients to ventricular
tachycardia, heart failure, and sudden cardiac death. However, due to
multiple disease variants, it can involve both ventricles or
predominantly the left ventricle with atypical manifestations. Recent
post-mortem studies of patients with Arrhythmogenic Cardiomyopathy (ACM)
suggest left ventricular involvement in up to 87% of
patients.1 Abnormal ECG findings and ventricular
arrhythmias may often precede abnormal imaging or structural findings.
To date fifteen genes have been identified to cause ARVC with a subset
encoding for desmosomal proteins including Plakoglobin
(JUP). 2 Phenotypic expression is highly variable, but
some evidence suggests young athletic males tend to have a more
malignant disease course in part due to their level of hormonal and or
physical activity, which in turn contributes a greater degree of
mechanical cardiac stress.3
We present a case of a 21-year-old male with a genetically proven family
history of ARVC who presented to the hospital with near syncope and
through extensive workup, had no evidence of ARVC on initial imaging
(echo and CMR). Subsequently, he was found to have multiple episodes of
ventricular ectopy and tachycardia. During his second hospitalization,
work-up demonstrated atypical, predominantly left ventricular
dysfunction on echocardiogram with evidence of new, leftventricular fibrosis on repeat CMR study. A third CMR scan showed
interval improvement in myocardial fibrosis once exercise was limited.