AUTONOMIC DYSFUNCTIONIN YOUNG ADULTS WITH THE MARFANOID HABITUSAND MITRAL VALVE PROLAPSE
Background: Dysfunction of autonomic nervous system (ANS) is frequently registered in patients with Inherited connective tissue disorders such as Marfan syndrome and mitral valve prolapse(MVP).But the autonomic control of heart rate of the persons with the marfanoidhabitus(MH) has not been studied yet.Our aim was to assess the heart rate variability(HRV) and the cardiovascular tests according to Ewing in young adults with MH.
Methods: We was studied 15young malewith MVP and31young male with MH (mean age 19.04±2.3).Control group was formed by13 age-matched healthy subjects. TheHolter monitoring with the calculation of HRV and the cardiovascular tests (the heart rate responses to the Valsalva maneuver, standing up(30:15ratio) and deep breathing; and the postural blood pressure change)according to Ewing were performed.
Results: HRV analysis showed a significant decrease of pNN50 and RMSSD in the MH group and MVP group vs. control group (21,6 vs. 55,2 and 42,5 vs. 63,3, accordingly, p>0,05). But these indices were lowest inthe MVP group (8,2 and 36,9, accordingly). Spectral analysis of HRV also showed significantly lower values in patients with MVP. Decreasingof these parameters in the MH group was not significant.Results of cardiovascular tests in the control group were normal. 30:15 ratio was abnormal in 51% persons with MVP and 38% persons with MH.Score of the battery of cardiovascular tests according to Ewingshowed a normal result in 45% persons with MH and 20% persons with MVP only. 20% of people with MVP revealed "definite involvement" and 60% - the "early involvement" on the parasympathetic part of the ANS.
Conclusion: Autonomic control of heart rate in MVP and MH people characterized by increasing ofsympathetic tone of ANS. 80% of MVP people and half of MH subjects have abnormal result one or more cardiovascular tests.