Multiple Myocardial Hamartomas Causing Ventricular Tachycardia in Young Children: Combined Surgical Modification and Medical Treatment

To describe two cases of incessant ventricular tachycardia caused by multiple myocardial hamartomas. Two infants, 13 and 14 months old, who had had multiple episodes of symptomatic tachycardia were referred to our institution. Incessant ventricular tachycardia was diagnosed. Initially, the patients received pharmacologic therapy. The recurrent tachycardia resulted in notable hemodynamic instability. No structural abnormalities were detected on the echocardiograms. In one patient, an electrophysiologic study revealed that the site of ventricular ectopic beats was in the anterolateral wall of the left ventricle, midway between the apex and the base. In the other patient, a preoperative electrophysiologic study was not undertaken because of the inability to obtain central venous access. Diffuse hamartomas were found throughout the ventricular myocardium in both patients. Surgical resection and cryoablation of the lesions in combination with medical therapy helped control the tachyarrhythmia. At 7 and 17 months postoperatively, the patients were in normal sinus rhythm and were receiving medication. In young children who have incessant ventricular tachycardia but no lesion evident on echocardiography, angiography, or other imaging modalities, a myocardial tumor should be suspected, and pharmacologic therapy should be instituted. If the medical regimen fails, surgical intervention should be undertaken, directed at areas localized by inspection and by preoperative and intraoperative electrophysiologic studies.