As in rhabdomyomas, the ECG is impo

As in rhabdomyomas, the ECG is important in the evaluation of pediatric patients with cardiac fibromas. Baseline
studies show abnormalities consistent with extensive intramural involvement, including partial to complete bundle
branch block and delayed progression of the terminal R wave (118,120,122). The ECG may show QRS axis deviation,
atrial enlargement, or ventricular hypertrophy (31, 32, 33 and 34,116,120,122). Similar to rhabdomyomas, cardiac
fibromas invariably have ST-T wave abnormalities consistent with strain or ischemia (31, 32, 33, 34 and
35,120,122, 123, 124 and 125,127). These changes have been reported to revert to normal after successful surgery
(31,35). Life-threatening arrhythmias can be the primary mode of presentation (31,32,119,123). These arrhythmias
include complete atrioventricular block, ventricular tachycardia, and, rarely, supraventricular tachycardia. The
diagnosis of a cardiac fibroma often is not established until autopsy, with arrhythmia the presumed cause of death
(120). In a recent single institution review of 25 patients with fibromas, 16 (64%) had ventricular tachycardia; two
presented with ventricular fibrillation and cardiac arrest (101). Thirteen of sixteen had complete or partial tumor
resection and ventricular tachycardia was eliminated in all cases (101).