title: [Effect of subclinical hypothyroidism treatment on selected cardiovascular parameters].
abstract: The impact of subclinical hypothyroidism (SH) on the cardiovascular system has not been well determined. Due to contradictory views on clinical consequences of SH there is no clear opinion on the indications for treatment of this disorder. The aim of study was to analyse the L-thyroxin therapy effect on normalization of cardiac irregularities in patients with SH observed in physical, electrocardiographic (at rest and 24-hour) and echocardiographic examinations.
  
  
  METHODS
  25 patients with SH and 25 in euthyreosis --C were included in the study, mean age +/- SD: SH- 43 +/- 17.4; C--51 +/- 17.2; NS. The frequency of irregularities in the physical, echocardiographic, electrocardiographic (at rest and 24-hour) examinations in both examined groups were compared. The effectiveness of a six-month treatment of SH as well as the impact of normalization of the TSH on results of the above tests were also analyzed.
  
  
  RESULTS
  It was observed that SH does not significantly affect results of the physical examination. However, normalization of the TSH decreased differences between the SH and C groups with regard to the frequency of irregularities in rest electrocardiographic examination (SH: 60% vs. C: 24%, p < 0.01). It also reduced the total number of irregularities observed in echocardiographic examination (p < 0.01). The changes included mainly an improvement of systolic and diastolic functions of the left ventricle. Moreover, less intensive supraventricular and ventricular arrhythmia in 24-hour electrocardiographic examination in some patients as well as an average positive correlation (R = 0.420, p < 0.05) between the number of irregularities in this examination and the TSH level were also observed.
  
  
  CONCLUSIONS
  Normalization of the TSH level after a six-month treatment period contributes to positive changes with regard to essential cardiac parameters in some patients.
authors.forename: Michał
authors.initials: M
authors.lastname: Krysicki
authors.forename: Ewa
authors.initials: E
authors.lastname: Slusarczyk
authors.forename: Bozena
authors.initials: B
authors.lastname: Popowicz
authors.forename: Joanna
authors.initials: J
authors.lastname: Jankiewicz-Wika
authors.forename: Mariusz
authors.initials: M
authors.lastname: Klencki
authors.forename: Dorota
authors.initials: D
authors.lastname: Słowińska-Klencka
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D004452:Echocardiography; D004562:Electrocardiography; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications* / Q000188:drug therapy*; D008875:Middle Aged; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000627:therapeutic use*; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*
chemical_list: D013972:Thyrotropin; D013974:Thyroxine