title: Cardiorespiratory effects of isosorbide dinitrate and nifedipine in combination with nadolol: a double-blind comparative study of beneficial and adverse antianginal drug interactions.
abstract: Combinations of 2 or 3 drugs are often used to treat angina pectoris, but their combined cardiorespiratory effects have not been investigated. Using a randomized, double-blind, placebo-controlled protocol, the effects of nadolol alone and nadolol in combination with isosorbide dinitrate and nifedipine were compared, in low and high doses, on antianginal efficacy, respiratory functions and arterial blood oxygen saturation (SaO2) in 19 patients with stable angina pectoris. A complete assessment including a bicycle exercise test with the measurement of the sum of ST-segment depression in all leads (sigma ST) was carried out every 2 weeks. The frequency of anginal attacks and nitroglycerin consumption was reduced significantly (p less than 0.001) by nadolol alone and in combination with the other drugs. Nadolol caused a slight reduction in the forced expiratory volume in 1 second, which was improved by isosorbide dinitrate and nifedipine. The sigma ST profile (basal, at peak exercise and 2 and 5 minutes after exercise) was decreased by nadolol alone and in combination with the other drugs, although the greatest reduction was achieved with large doses of nifedipine and nadolol. The rest and postexercise SaO2 decreased after nadolol alone and in combination with isosorbide dinitrate, but recovered to pretrial values after nifedipine and nadolol. With all drug combination, sigma ST depression was greater when the postexercise SaO2 was less than 92%, and decreased (p less than 0.05) in the same patients when their postexercise SaO2 was greater than 92%.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage* / Q000633:toxicity; D000328:Adult; D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage* / Q000633:toxicity; D008297:Male; D008875:Middle Aged; D009248:Nadolol; D009543:Nifedipine / Q000008:administration & dosage* / Q000633:toxicity; D010100:Oxygen / Q000097:blood; D005082:Physical Exertion; D011412:Propanolamines / Q000008:administration & dosage* / Q000633:toxicity; D011897:Random Allocation; D012119:Respiration / Q000187:drug effects*; D012129:Respiratory Function Tests
chemical_list: D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D009248:Nadolol; D009543:Nifedipine; D007548:Isosorbide Dinitrate; D010100:Oxygen