COMBINED IMMUNOSUPPRESSIVE THERAPY IN PATIENTS WITH SEVERE CHRONIC MYOCARDITIS AND VENTRICULAR ARRHYTHMIAS

The aim of the research to assess the effectiveness of combined immunosuppressive therapy with azathioprine and methylprednisolone for correcting ventricular rhythm disturbances in patients with severe chronic myocarditis based on the results of a 6-month observation.Material and methods. The study involved 50 patients with severe chronic myocarditis lasting more than 6 months and an ejection fraction (EF) of the left ventricle <40% at the time of enrollment. The patients were divided into two groups: Group 1 included 26 individuals who showed no positive dynamics on the background of previous glucocorticoid (GC) therapy. These patients were prescribed azathioprine (Imuran) at a dose of 1 mg/kg of body weight for 6 months, in combination with methylprednisolone at a dose of 0.25 mg/kg per day for 3 months, with a weekly dose reduction of 1 mg until discontinuation after 6 months. Group 2 consisted of 24 patients who had not previously received glucocorticoids; they were prescribed methylprednisolone at a dose of 0.25 mg/kg per day for 3 months, with a dose reduction following the same scheme. Daily ECG monitoring, cardiac magnetic resonance imaging, and transthoracic echocardiography were conducted before the initiation of immunosuppressive therapy and after 6 months of treatment.Results. Before the initiation of immunosuppressive therapy, both groups of patients were comparable in baseline parameters of the structural and functional state of the heart, the presence of inflammatory and fibrotic changes in the myocardium, and the frequency of rhythm disturbances. After 6 months, a decrease in the left ventricular end-diastolic volume (LVEDV) was observed, averaging 15.2% (P < 0.01) in Group 1 and 12.1% (P < 0.05) in Group 2, respectively. The ejection fraction (EF) of the left ventricle in Group 1 patients was, on average, 12.5% higher (P < 0.05) compared to that in Group 2 patients. According to the Holter ECG analysis after 6 months of observation, the number of ventricular extrasystoles and episodes of non-sustained tachycardia (NST) in Group 2 patients was 1.5 and 2 times higher, respectively, than in Group 1 patients. MRI results after 6 months showed that in Group 1 patients, the number of left ventricular segments affected by inflammatory changes decreased from (7.2 ± 0.8) to (2.1 ± 0.21) segments (P < 0.001), while in Group 2 it decreased from (5.4 ± 0.77) to (2.8 ± 0.25) segments (P < 0.001). The number of segments with fibrotic changes was comparable in both groups, averaging (4.6 ± 0.45) and (4.2 ± 0.41), respectively.Conclusions. In patients with severe myocarditis, the administration of combined immunosuppressive therapy with azathioprine and glucocorticoids over 6 months was associated with a significant improvement in left ventricular systolic function, a reduction in the number of segments with inflammatory and fibrotic changes as assessed by cardiac MRI, and a substantial decrease in the frequency of ventricular arrhythmias, particularly episodes of non-sustained ventricular tachycardia, compared to patients receiving therapy with methylprednisolone.