Interactions of vasodilators with calcium entry- and beta-blockers in patients with coronary heart disease.
Combinations of antianginal drugs may be used for an additive effect against angina, but also to off-set unwanted effects of one drug with another, either by direct effects or by a reduction of dosage of each drug. Based on earlier studies with separate drugs we have now examined the effect of 150 mg bupranolol combined with 40 mg isosorbide dinitrate (ISDN) in one retarded tablet, given twice daily. 22 patients with CHD entered the study, 11 of those with and 11 without signs of ischemia during exercise. In an acute radionuclide ventriculographic (RNV) study 2 h after the tablet, ejection fraction (EF) during exercise increased only in patients with exercise ischemia (+6%, p less than 0.001). In the other patients EF did not change. After 21 days of treatment echocardiographically determined end-systolic and end-diastolic diameters decreased, resulting in an increase of shortening fraction by 15.6% (p less than 0.05). Heart rate, systolic and diastolic pressure and ST-segment depression decreased significantly. In another acute RNV study the effect of a venous vasodilator, molsidomine 4 mg s.l., was examined after nifedipine 10 mg s.l. in 19 patients with CHD, 9 with and 10 without exercise ischemia. Differences between drugs were most prominent during exercise. In the nonischemic group EF rose by 6.6% after nifedipine (n.s.) and by 14% after molsidomine (p less than 0.01 against control). In the group with ischemia EF rose by 12.6% after nifedipine and by 17.4% after additional molsidomine, significant against control (p less than 0.01) as well as against nifedipine (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
D002046:Bupranolol / Q000008:administration & dosage; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D003327:Coronary Disease / Q000188:drug therapy* / Q000503:physiopathology; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D005080:Exercise Test; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage; D008875:Middle Aged; D008981:Molsidomine / Q000008:administration & dosage; D009543:Nifedipine / Q000008:administration & dosage; D011943:Receptors, Adrenergic, beta / Q000008:administration & dosage*; D014665:Vasodilator Agents / Q000008:administration & dosage*
D002121:Calcium Channel Blockers; D011943:Receptors, Adrenergic, beta; D014665:Vasodilator Agents; D002046:Bupranolol; D008981:Molsidomine; D009543:Nifedipine; D007548:Isosorbide Dinitrate