Dangers of delay of initiation of either thrombolysis or primary angioplasty in acute myocardial infarction with increasing use of primary angioplasty

We observed treatment delays and suboptimal outcomes when beginning to treat patients with acute myocardial infarction (AMI) with primary angioplasty. Of the 37 patients treated during a 12-month period, 12 (32%) required either emergency bypass surgery or died. Delayed time intervals to balloon reperfusion (mean 134 minutes) probably contributed to these adverse outcomes, with hemodynamic instability requiring pressors or intra-aortic balloon pumping in 15 patients, 12 (75%) before the first balloon inflation. Eleven of the 12 patients with significant adverse outcomes required such intervention. As angioplasty use increased, time intervals to thrombolysis in those not treated with angioplasty increased from an average of 29 minutes (53% treated less than the notional standard of 30 minutes) to 39 minutes (32% treated < 30 minutes, p < 0.001). During the last 2 months of the study period, the time intervals had increased to 48 minutes (14% treated < 30 minutes, p < 0.0001). There was no change in thrombolytic time intervals at a local community hospital that did not offer primary angioplasty. Emergency Department physician confusion about the best therapy (angioplasty or thrombolysis) was documented in the medical records in 42% of cases (53 of 127). Confusion regarding therapy of AMI led to unacceptable delays in the administration of thrombolytic agents and probably contributed to the adverse outcomes in patients receiving primary angioplasty. (C) 1998 by Excerpta Medica, Inc.