Isolated ventricular noncompaction mimicking arrhythmogenic right ventricular cardiomyopathy — A study of nine patients

Abstract

Isolated ventricular noncompaction is considered to predominantly affect the left ventricle. It is characterized by increased left ventricular wall thickness and deep intertrabecular recesses with to-and-fro blood flow that remains in continuity with the ventricular flow. Aim of the study was to present a group of patients with isolated noncompaction of both ventricles mimicking arrhythmogenic right ventricular cardiomyopathy (ARVC). Reported group consisted of 9 pts initially diagnosed with ARVC (mean age 37.9 y, 7 male), who underwent basic clinical evaluation. CMR was performed in 8 pts, cardiac catheterization in 2 pts and endomyocardial biopsy in 2 pts. Mean age at presentation of first symptoms was 23.5 y (5-44 y). Heart failure symptoms were observed in 4 pts, atrial fibrillation in 3 pts, ventricular tachycardia in 2 pts (polymorphic--in 2 pts) and syncope in 3 pts. Final diagnosis of noncompaction was established according to generally accepted criteria. Morphologic and/or functional changes in the right ventricle were seen in 9 pts (100%): enlargement and hypertrabeculation of the right ventricle in all pts, global hypokinesis in 4 pts, focal wall motion abnormalities and/or bulges typical for ARVC in 5 pts. Two pts had significant tricuspid regurgitation. Endomyocardial biopsy (2 pts) showed abnormal thick endocardium, interstitial fibrosis, myocardial damage and lymphocyte infiltration. 1) Noncompaction of ventricular myocardium should be considered during the evaluation of right ventricular cardiomyopathies with excessive trabeculation. 2) In problematic cases Task Force criteria for ARVC should be used to improve the accuracy of assessment.