Clinical significance of QTc interval duration in diagnostics and drug control of permanent atrial fibrillation for development of proposals for increasing quality of its diagnostics and therapy was studied. Thesis is dedicated to determination of clinical significance of QTc interval duration in diagnostics and drug control of permanent atrial fibrillation. On the base of studying clinical-instrumental indexes (QTc duration, systolic and diastolic arterial pressure, heart rate, ventricle rate, left atrium size, left ventricle posterior wall thickness, left ventricle end-diastolic diameter, left ventricle end-sistolic diameter, left ventricle end-diastolic volume, left ventricle end-systolic volume, left ventricle stroke volume, left ventricle ejection fraction, heart failure functional class, heart failure stage, arterial hypertension stage, stable angina pectoris functional class) in patients with permanent atrial fibrillation before, after 2 weeks, 1, 6 months and 1 year after treatment with amiodarone, beta-blockers and its combination, it was revealed that beta-blockers treatment of patients with permanent atrial fibrillation provides reaching the strict ventricle rate control in 38% of patients with normal QTc and in 25% of patients with prolonged QTc, reaching lenient ventricle rate in 61% of patients with normal QTc and in 75% in patients with prolonged QTc, positively influencing on heart failure functional class, stable angina pectoris functional class, arterial hypertenstion stage and left ventricle hemodynamic indexes. It is defined that treatment with amiodarone of patients with permanent atrial fibrillation provides more effective than treatment with beta-blockers reaching of strict ventricle rate control in 41% patients with normal QTc and in 36% in patients with prolonged QTc, reaching lenient ventricle rate control in 59% patients with normal QTc and 64% patients with prolonged QTc, leading to decreasing of heart failure functional class, stable angina pectoris functional class and improvement of left ventricle hemodynamic indexes in both, normal and prolonged QTc. It is shown that in patients with permanent atrial fibrillation therapy with amiodarone and beta-blockers combination provides more effective than monotherapy with amiodarone and beta-blockers reaching of strict ventricle rate control in 78% patients with normal QTc and in 65% in patients with prolonged QTc, reaching lenient ventricle rate control in 22% patients with normal QTc and 35% patients with prolonged QTc, decreasing heart failure functional class, stable angina pectoris functional class, artrial hypertension stage, decreasing left atrium size with positive influence on left ventricle hemodynamic indexes independently on QTc duration class. It is shown, that prognostic significant criteria of ventricle rate control effectiveness in patients with normal QTc are systolic arterial pressure (F = 3,8), ventricle rate (F = 3,9), left atrium size (F = 3,2) and in patients with prolonged QTc - age (F = 4,4), diastolic arterial pressure (F = 3,1), QTc duration (F = 5,6), left ventricle ejection fraction (F = 3,1).
