Medical treatment of patients with stable angina pectoris referred for coronary angiography: Failure of treatment or failure to treat

Background: Patients referred for elective coronary arteriography because of stable angina pectoris frequently do not receive appropriate medical therapy prior to arteriography. Persistence of symptoms due to lack of appropriate therapy may influence the decision to catheterize and the treatment chosen following catheterization. Hypothesis: The present study evaluates whether patients with stable angina pectoris referred for cardiac catheterization received optimal therapy prior to the procedure. We also evaluated whether medical therapy was optimized as a result of the hospitalization for catherization. Methods: We evaluated prospectively the adequacy of medical therapy in 333 consecutive patients undergoing elective coronary arteriography. Of these, 160 had stable angina pectoris as their main problem and constituted the study group. Results: Mean duration of angina was 7.5 +/- 6.3 months. Canadian Cardiovascular Society angina grade I was present in 20, grade 2 in 77, grade 3 or 4 in 63 patients. Arteriography showed a greater than or equal to 50% coronary stenosis in 141 of 160 patients. Aspirin was used by 96%, and 86% received at least one drug aimed at relieving anginal symptoms: beta blockers in 69%, calcium blockers in 30%, and long-acting nitrates in 29%. Antianginal drugs and drugs aimed at treating risk factors were usually taken at a low, subtherapeutic dosage. Only 35 of 110 patients taking beta blockers had a resting heart rate of less than or equal to 60/min. Following catheterization, 88 of 141 patients with coronary stenosis of greater than or equal to 50% underwent percutanous intervention and 5 had urgent surgery. Optimization of treatment was advised in only 7 of 48 patients for whom medical therapy or elective surgery was recommended. Conclusion: Patients with stable angina pectoris are frequently referred for cardiac catheterization without making a serious attempt to control their symptoms by medical therapy. Risk factors are undertreated. With proper pharmacotherapy, many patients might have become asymptomatic and have chosen not to undergo catheterization and subsequent percutaneous interventions.