Detection of dysrhythmia in pediatric patients with mitral valve prolapse.

The association of dysrhythmias with mitral valve prolapse in pediatric patients was investigated by graded treadmill exercise testing and 24-hour ambulatory ECG monitoring. Twenty-six unselected patients with a clinical diagnosis of mitral valve prolapse confirmed by echocardiography or angiocardiography or both were studied. On 24-hour ambulatory ECG monitoring, six patients (23%) had potentially serious ventricular dysrhythmias. Five of these patients also manifested ventricular dysrhythmias on treadmill exercise testing. Neither standard ECG abnormalities nor clinical symptoms correlated with detected dysrhythmias. This study shows that potentially serious ventricular arrhythmias are common in pediatric patients with mitral valve prolapse and that ambulatory ECG monitoring and treadmill exercise testing are useful for detecting dysrhythmias.