Respiratory sinus arrhythmia (RSA), i.e. heart rate (HR) variations
during inspiration and expiration, is considered as a noninvasive
index of cardiac vagal control. Mitral valve prolapse (MVP) could
be associated with increased cardiovascular risk; however, the
studies are rare particularly at adolescent age. Therefore, we
aimed to study cardiac vagal control indexed by RSA in adolescent
patients suffering from MVP using short-term heart rate variability
(HRV) analysis. We examined 12 adolescents (girls) with MVP (age
15.9±0.5 years) and 12 age and gender matched controls. Resting
ECG was continuously recorded during 5 minutes. Evaluated HRV
indices were RR interval (ms), rMSSD (ms), pNN50 (%), log HF
(ms2
), peak HF (Hz) and respiratory rate (breaths/min). RR interval
was significantly shortened in MVP group compared to controls
(p=0.004). HRV parameters-rMSSD, pNN50 and log HF were
significantly lower in MVP compared to controls (p=0.017,
p=0.014, p= 0.015 respectively). Our study revealed reduced RSA
magnitude indicating impaired cardiac vagal control in MVP already
at adolescent age that could be crucial for early diagnosis of
cardiovascular risk in MVP.