In a recent paper in the Journal of American College of Cardiology, a group of investigators led by McKenna WJ describes the clinical and genetic profile of 42 patients with predominant left ventricular involvement in arrhythmogenic cardiomyopathy which they call “left dominant arrhythmogenic cardiomyopathy” (LDAC). LDAC manifests clinically with inverted T waves in the lateral and/or inferior leads and ventricular arrhythmias of right bundle branch block morphology suggestive of left ventricular origin. LDAC is differentiated from other forms of non-ischemic cardiomyopathy by the propensity to ventricular arrhythmias out of proportion to left ventricular dysfunction. The ECG changes in these patients are often dissmissed as benign, in the absence of coronary artery disease. Five of the seven mutations detected occurred within the gene encoding desmoplakin, possibly indicating that desmosomal mutations are more likely to involve the left ventricle.

Patients also had echocardiographic features of left ventricular non compaction and a few of these patients also had desmosomal gene mutations, possibly indicating a link between left ventricular non compaction and LDAC.