[Effects of antianginal drugs on left ventricular diastolic filling in patients with ischemic heart disease].

To study the acute effects of isosorbide dinitrate (ISDN), nifedipine, propranolol and placebo on left ventricular diastolic filling in patients with myocardial ischemia, we repetitively performed exercise radionuclide angiography (RNA) following random assignment of each drug in 12 patients with effort angina pectoris, and 5 normal controls. Left ventricular time activity curves were constructed using computer technique. We obtained changes of hemodynamic parameters such as endodiastolic volume, systemic vascular resistance and ejection fraction. The peak filling rate (PFR), and filling rate in the first third of the diastolic period (1/3 FR) were used as the indexes of LV diastolic filling. 1/3 FR remained unchanged during peak exercise by the patients, while it increased significantly in normal controls. After administration of ISDN and nifedipine, 1/3 FR increased significantly during peak exercise by the patients. Especially after nifedipine, 1/3 FR improved significantly compared with the improvement after ISDN, although these two drugs had the same effects on systolic function. These findings showed that 1/3 FR was reliable as an indicator of LV diastolic filling in ischemic heart disease, and nifedipine improved LV diastolic filling not only by improving ischemic changes in myocardium but also by it's direct effect on left ventricular relaxation.