The Relationship between 24 Hour Total Heart Beats or Ventricular Arrhythmias and Cardiopulmonary Function in Patients with Duchenne's Muscular Dystrophy

摘要

To evaluate the relationship of 24 hour total heart beats (THB) or ventricular arrhythmias and cardiopulmonary function, 29 patients with Duchenne's muscular dystrophy (DMD) were studied using Holter electrocardiographic and echocardiographic recordings.The THB were 144, 428±12, 237 beats per 24 hours in the child group (8 to 15 years, n=12) and 136, 355±19, 991 beats per 24 hours in the adult group (16 to 25 years, n=17). The THB in the adult group significantly correlated well with %VC (r=-0.74), PaCO2 (r=0.67), PaO2 (r=-0.59) and the respiration rate (r=0.71), but not in the child group. In both groups, the echocardiographic parameters of the left ventricular size and function (left ventricular dimension, ejection fraction and D/S ratio) did not significantly correlate with the THB. Premature ventricular contractions (PVCs) were observed in 14 of the 29 patients (48.3%), and high risk PVCs (Lown's grade 3-4b) were observed in 11 of these 14 patients (78.6%). Echocardiographic parameters of the left ventricular function in the high risk PVC group were significantly deteriorated as compared with the low risk PVC group (Lown's grade 0-2) (p<0.02-P<0.001).We conclude that the THB in the adult group was mainly related to depressed pulmonary function, and the severity of the PVCs in both the adult and child groups was mainly related to the degree of left ventricular dysfunction.