effects of mitral valve prolapse on heart rate variability and the autonomic nervous system in children

Background: patients with mitral valve prolapse (mvp) may reveal symptoms of autonomic dysfunction and heart rate variability (hrv). we sought to explore the autonomic nervous system in children with mvp. methods: this cross-sectional study enrolled 60 children aged between 5 and 15 years with mvp and 60 age- and sexmatched healthy children as controls. two cardiologists performed electrocardiography and standard echocardiography. hrv parameters were explored via 24-hour rhythm 3-channel holter monitoring. the depolarization of ventricular and atrial parameters, comprising qt max and min, qtc intervals, qt dispersion, p maximum and minimum, and p-wave dispersion, was measured and compared. results: the mean age was 13.12±1.50 years in the mvp group (f/m: 34/26) and 13.20±1.81 years in the control group (f/m: 35/25). the maximum duration and p-wave dispersion in the mvp group were significantly different from the healthy children (p<0.001). the longest and shortest qt dispersion values and qtc values were significantly different between the 2 groups (p=0.004, p=0.043, p<0.001, and p<0.001, respectively). the hrv parameters were significantly different between the 2 groups, too. conclusion: decreased hrv and inhomogeneous depolarization showed that our children with mvp were prone to atrial and ventricular arrhythmias. furthermore, p-wave dispersion and qtc could be used as prognostic markers of cardiac autonomic dysfunction before it is diagnosed by 24-hour holter monitoring.