The purpose of the study was to assess the influence of structural and functional changes in the myocardium of the right and left ventricle (RVand LV) on the development of ischemia and arrhythmia in chronic obstructive pulmonary disease (COPD) and bronchial asthma (BA). The subjects of the study were 156 patients with either persistent BA (81 patients) or COPD (75 patients). Patients with decompensated cor pulmonale were excluded. ECG, 24-hour ECG monitoring, and echocardioscopy were performed. The study found that the occurrence of supraventricular and ventricular extrasystoles (SVES and VES) in patients with mild COPD or BA depended on the condition of RV diastolic function and on LV diastolic function and myocardial ischemia as well in COPD. In moderate BA the processes of myocardial remodeling correlate with myocardial ischemia, RV dysfunction and increased pulmonary arterial pressure (PAP), as well as with lipid dismetabolism. The appearance of SVES in patients with severe BA is connected with interventricular septal hypertrophy, LV dysfunction, and increased PAP, while VEC appear due to myocardial ischemia and hypercholesterolemia. In severe COPD the occurrence of SVES and VES does not depend on structural and functional changes in the myocardium, while myocardial ischemia is connected with LV hypertrophy. In BA ischemia depends on the development of RV and LV diastolic dysfunction, as well as hypercholesterolemia.