Abnormal ambulatory electrocardiographic findings in patients with the Marfan syndrome.

OBJECTIVES: The aim of this study was to assess the prevalence of cardiac dysrhythmias and abnormalities of conduction and repolarization in the Marfan-syndrome (MFS). SUBJECTS AND METHODS: Forty-five adult MFS patients (25 men) and healthy age and sex matched controls. A 24-h ambulatory electrocardiogram was recorded.
RESULTS: There was no difference in heart rates between the two groups. Two MFS patients had atrial fibrillation. The median number of premature atrial beats was 12/24 h in the MFS group vs. 6/24 h in the controls (P < 0.05), and the respective medians of premature ventricular beats were 17/24 h vs. 1/24 h (P < 0.001). Five patients but no healthy person had salvos of > or = 3 premature ventricular complexes (P < 0.05). Ventricular premature beats with R on T configuration were recorded in nine patients but in none of the control subjects (P < 0.05). Both PQ and QT intervals at heart rates of 60, 80 and 100 beats min-1 were longer in the MFS group compared with healthy persons (P < 0.005). Also ST segment depression was seen more often in the MFS group (17/43 vs. 6/45; P < 0.05). In patients with MFS, the findings at ambulatory electrocardiography showed no association with echocardiographically determined aortic root diameter, left atrial diameter or left ventricular diameters, wall thickness and systolic function. Nor did the electrocardiographic findings correlate with the presence of mitral or tricuspid valve prolapse.
CONCLUSIONS: Patients with MFS have a higher prevalence of cardiac dysrhythmias than healthy persons. Likewise they have prolonged atrio-ventricular conduction time and disturbed depolarization as suggested by longer QT intervals and more common ST segment depression.