Effectiveness of Mono Mac was assessed in patients with ischemic heart disease (IHD) and concomitant polycythemia vera (PV). 24-h ECG-monitoring, stress-echoCG were performed in 28 patients aged 35-79 years with painless myocardial ischemia (group 1) and painful form (group 2). Mean dose of Mono Mac was 56.4 mg/day. Clinical response was achieved. Positive changes were observed in decreased number of anginal attacks and nitroglycerin tablets, ST wave depression, number of ischemic episodes, improvement of hemodynamics. It is concluded that Mono Mac has a marked clinical effect in IHD patients having associated polycythemia vera.