Clinical Profile and Outcome of Idiopathic Restrictive Cardiomyopathy

Abstract

To the Editor: We read the article by Ammash et al1 with great interest. The authors retrospectively identified 94 patients with idiopathic restrictive cardiomyopathy on the basis of a triad of echocardiographic features, including biatrial enlargement, nondilated ventricles, and normal ventricular wall thickness, in the absence of conditions known to cause pericardial disease or restrictive cardiomyopathy. The validity of this definition, however, is debatable when 74% of the patients in the cohort were in atrial fibrillation. Although atrial fibrillation is often the consequence of atrial dilatation, not as well known is the fact that atrial fibrillation may itself induce the enlargement of both atria. Sanfilippo et al2 performed serial echocardiography a mean of 20.6 months apart in a …