Arrhythmogenic right ventricular cardiomyopathy with evidence of biventricular involvement

Abstract

The case: A 37-year-old man was admitted to our hospital with recurrent palpitations. Arrhythmogenic right ventricular cardiomyopathy had been diagnosed 10 years before admission and had been treated with sotalol. Physical examination revealed a blood pressure of 160/98 mm Hg and a heart rate of 150 beats/min, but no other abnormalities. An electrocardiogram showed ventricular tachycardia ( Fig. 1) that, after an intravenous infusion of procainamide, converted to sinus rhythm with epsilon waves and T-wave inversions in the precordial leads (Fig. 2). An echocardiogram showed that the right side of the heart was dilated in the absence of intracardiac shunts and that there was impaired left ventricular function with regional wall-motion abnormalities. Cardiac catheterization, performed to exclude coronary artery disease, showed normal coronary arteries. The patient was referred for cardiac magnetic resonance imaging.Spin echo images showed a thinned right ventricular free wall and focal hyperintensity suggestive of fatty infiltration at the level of the apex and right ventricular free wall (Fig. 3). Typical focal dyskinetic bulging in the free wall of the right ventricle was seen on cine imaging (Fig. 4, D and E). The left ventricle also showed regional wall thinning with wall-motion abnormalities in the inferoposterolateral region and moderate impairment of global left ventricular function (Fig. 4, A and B). Late gadolinium-enhanced images showed various areas of hyperenhancement in the inferoposterolateral region, septum and right ventricular free wall (Fig. 4, C and F). See videos online at www.cmaj.ca/cgi/content/full /176/13/1819/DC1.The combination of ventricular tachycardia of right ventricular origin, epsilon waves on the electrocardiogram, right ventricular aneurysms and the findings of cardiovascular magnetic resonance imaging in the left ventricle in the absence of coronary artery disease were diagnostic of arrhythmogenic right ventricular cardiomyopathy with biventricular involvement. The patient had symptoms of ventricular arrhythmia despite adequate sotalol therapy; thus, catheter ablation was considered but was unsuccessful because of multiple foci. Despite a lack of evidence in the literature, the patient was given amiodarone therapy. He showed a favourable response and was still free of symptoms on follow-up 3 years later.Arrhythmogenic right ventricular cardiomyopathy is a disease of the right ventricle of the heart with a genetic basis. It is characterized by myocardial atrophy and fibrofatty replacement, and ventricular arrhythmias. dominant trait with incomplete penetrance, although recessive forms have been described. 4 The prevalence in the general population is about 1 in 5000, and it is an important cause of sudden cardiac death in young adults. 5,6 This pathological diagnosis is difficult to establish in clinical practice; thus, an expert consensus group has proposed criteria to allow confirmation of the diagnosis (Box 1).3 Genetic analysis, although in its infancy for this disease, may b...