Arrhythmias and left ventricular hypertrabeculation /noncompaction

Arrhythmias in left ventricular hypertrabeculation/noncompaction (LVHT) comprise sustained or non-sustained ventricular tachycardia (VT) (n=135), atrial fibrillation (AF) (n=96) AV block (n=55) and QT prolongation (n=47). The prevalence differs between children and adults. In children most frequent are WPW-syndrome (n=24), AV block (n=24), VT (n=17) and bradycardia (n=15). In adults most frequent arrhythmias are VT (n=118), AF (n=95), QT prolongation (n=42) and AV block (n=31). Some arrhythmias are more frequently reported in children than in adults like WPW-syndrome (24 vs. 17 patients), second-degree AV block (4 vs. 0 patients), bradycardia (15 vs. 3 patients) and ventricular fibrillation (VF) (9 vs. 5 patients). There are nearly no pediatric cases with AF (1 vs. 95 patients). In 120 patients implantable cardioverters/defibrillators have been implanted for primary or secondary prevention of sudden cardiac death. The pathomechanisms of arrhythmias in LVHT are largely unknown, especially if patients with LVHT and neuromuscular disorders are more prone to arrhythmias than patients without. There is a need to clarify risk factors for VT or VF because 19% of LVHT patients with VT or VF have a normal systolic function and demonstration of systolic dysfunction is no reliable risk marker. Data about long-term follow-up of LVHT patients with implanted cardioverters/defibrillators are necessary since the indication for prophylactic implantation is still unclear. AF in LVHT increases the embolic risk, thus it would be useful to know which LVHT patients who have sinusrhythm at baseline are prone to develop AF in order to start early with anticoagulant therapy.