[Effects of coronary surgery on silent ischemia]. / Influência da cirurgia coronária na isquémia silenciosa.

In order to assess the effects of coronary artery bypass surgery on silent myocardial ischemia, we studied a group of 39 consecutive patients, 38 male and 1 female with a mean age of 56 + 7 years, with stable chronic angina pectoris, by 48 hours-Holter monitoring and maximal treadmill exercise test before and after operation. The reduction of angina was 92% (p less than 0.0001) and of ischemia 57% (p less than 0.0001) after operation. Silent myocardial ischemia was detected in 21 patients (54%) before operation, 13 by Holter, 4 by exercise test and 4 by the two methods. After operation 13 patients (36%) continue to have silent ischemia depicted in 7 by Holter and in 7 by exercise test. No new patient developed silent ischemia after operation. The group of patients with silent ischemia preoperatively was not significantly different from the group without silent ischemia based on clinical and angiographic characteristics, results of surgery and exercise test parameters with exception of ST segment depression. In conclusion, silent myocardial ischemia may persist after successful coronary artery bypass surgery for the relief of angina pectoris, and should be monitored by serial Holter recordings and treated medically, if its prognosis and consequences proved to be similar to manifest symptomatic ischemia.

Evaluation of 2 intravenous thrombolytic agents (anisoylated plasminogen streptokinase activator complex versus streptokinase) in patients with acute myocardial infarction.

Ten patients with symptoms of acute myocardial infarction of less than 6 hours duration were randomised to receive either anisoylated plasminogen streptokinase activator complex [APSAC] (30U) or streptokinase (1,500,000U) intravenously. The aims of the study were to compare the angiographic patency of the infarct-related coronary arteries and to monitor drug safety and tolerance for up to 24 hours. The left anterior descending artery was occluded in 3, the left circumflex in 3 and right coronary artery in 4 patients. Time between onset of pain and treatment ranged from 150 to 330 minutes. At 90 minutes, 8 patients, 3 of 5 (60%) of the APSAC group and all of the streptokinase group, had patent arteries. No significant differences were found in measurements of coagulation. There were no haemorrhagic complications. One patient of the APSAC group had reinfarction 6 hours after treatment and died in cardiogenic shock. APSAC seems safe and is easier to use than streptokinase, and both agents result in patency in the majority of patients, although too few patients were included to allow a valid comparison. However, thrombolysis should be considered only a temporary solution in acute myocardial infarction, associated mainly with 3-vessel disease.