DISOPYRAMIDE IMPROVES THE BALANCE BETWEEN MYOCARDIAL OXYGEN-SUPPLY AND DEMAND IN PATIENTS WITH HYPERTROPHIC OBSTRUCTIVE CARDIOMYOPATHY

We evaluated the effects of disopyramide in terms of the balance betwe en myocardial oxygen supply and demand in patients with hypertrophic o bstructive cardiomyopathy (HOCM). The myocardial oxygen supply was eva luated by measuring coronary flow velocity and the myocardial oxygen d emand was assessed by the pressure-volume area (PVA). The time velocit y integral of coronary flow did not change significantly (20 +/- 6 to 21 +/- 8 cm), but the peak left ventricular pressure and left ventricu lar external work decreased significantly (206 +/- 44 to 157 +/- 37 mm Hg, P < 0.001; 1.09 +/- 0.33 to 0.80 +/- 0.23J/beat, P < 0.001) after disopyramide administration. From theoretical analysis using these dat a, we concluded that disopyramide improves the myocardial oxygen suppl y-demand balance in patients with HOCM.