title: Cardiac arrhythmias in adolescents with mitral valve prolapse and myxomatous degeneration of mitral valve leaflets.
abstract: BACKGROUND
  myxomatous degeneration (MD) of valve leaflets and other structures of the valve apparatus and the degree of its severity in particular is of great prognostic significance as this determines the risk of complications development as well as the prognosis. The aim of the paper was to assess heart rhythm and heart conduction disorders in adolescents with primary mitral valve prolapse (MVP) and myxomatous valve degeneration of various degrees.
  
  
  METHODS
  complete physical examination of 145 adolescents aged 12-16 with MVP was carried out. Patients were divided into four groups according to the degree of myxomatous degeneration (MD): group 1 - 29 patients without MD; group 2 - 43 patients with MD and 3-4 mm leaflets thickness; group 3 - patients with MD and 5-6 mm leaflets thickness; group 4 - patients with MD and 7-8 mm leaflets thickness. Our own methods used to determine the degree of MD are presented in the paper.
  
  
  RESULTS
  in general, significant increase in the total number of both ventricular and supraventricular arrhythmias was observed in all patients with myxomatous degeneration when compared with the group of patients with no MD. While in patients from group 2 the number of ventricular premature beats was 6.5 times higher than in group 1, it was 10 times higher in group 3 and 20 times higher in group 4. The same significant changes (p < 0.05) were seen in extrasystoles in Lown's grading (increase from grade I to grade IV), the episodes of ventricular tachycardia (VT) and their number, mean heart rate as well as maximal duration of ventricular tachycardia episodes.
  
  
  CONCLUSIONS
  thus, the presence of MD of mitral valve leaflets in MVP and its degree of severity in particular, were found to be the major risk factor in arrhythmia development.
authors.affiliation: Department Of Internal Therapy №1 Of Vinnitsa National Pirogov Memorial Medical University, Vinnitsa, Ukraine, e-mail: osovskayanatalia@gmail.com.
authors.forename: N Y
authors.initials: NY
authors.lastname: Osovska
authors.affiliation: Department Of Internal Therapy №1 Of Vinnitsa National Pirogov Memorial Medical University, Vinnitsa, Ukraine.
authors.forename: N V
authors.initials: NV
authors.lastname: Kuzminova
authors.affiliation: Department Of Clinical Pharmacology Of Kharkiv National Medical University, Kharkiv, Ukraine.
authors.forename: I I
authors.initials: II
authors.lastname: Knyazkova
mesh_terms: D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000209:etiology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000002:abnormalities*; D008945:Mitral Valve Prolapse / Q000150:complications*
keywords:  arrhythmias ;  hypersympathicotonia;  myxomatous degeneration of valve leaflet; mitral valve prolapse