Cardiac arrest and ventricular arrhythmia in adults with Ebstein anomaly and left ventricular non-compaction

Ebstein anomaly is a complex, congenital heart defect that is associated with a variety of cardiac abnormalities. Studies found a similar sarcomere gene mutation in patients with Ebstein anomaly (EA) and patients with isolated left ventricular non-compaction (LVNC).

We aimed to show the prevalence of LVNC and its potential relationship with severe cardiac events (VT - ventricular tachycardia, cardiac arrest) in adult patients with EA.

We conducted a retrospective search of our institutional database from 2010 to 2014 for patients with EA and reviewed patients' medical records (age, sex, clinical presentation, electrocardiographic, echocardiographic, and CMR - cardiac magnetic resonance features). We reviewed echocardiograms and CMR scans for concomitant morphological abnormalities (LVNC, PDA - patent ductus arteriosus, VSD - ventricular septal defect, ASD - atrial septal defect, mitral valve prolapse, BAV - bicuspid aortic valve, CoA - coarctation of aorta).

The studied group consisted of 84 consecutive patients (mean age 38±15 years, 50 women) with EA. We found four patients (4.8%) with LVNC, two of them had cardiac arrest, one had VT, and one was symptomless, but had QTc prolongation in Holter recordings. Concomitant abnormalities were VSD (4.8%), PDA (1.2%), CoA (1.2%), mitral valve prolapse (1.2%), and BAV (2.4%). The most common anomaly was ASD type II - 23 patients (27.3%) and WPW - Wolff-Parkinson-White's syndrome - 9 patients (10.7%).

Non-compaction is a notable abnormality in adult patients with EA and it may affect their prognosis. Although other concomitant lesions were more common, only patients with LVNC suffered from cardiac arrest or ventricular arrhythmia.