Treatment and outcome of myocardial infarction in hospitals with and without invasive capability

OBJECTIVES We sought to determine the extent to which-the capability of a h ospital to perform invasive cardiovascular procedures influences treatment and outcome of patients admitted with acute myocardial infarction (AMI). BACKGROUND Patients with AMI are usually transported to the closest hospita l. However, relatively few hospitals have the capability for immediate coro nary arteriography, percutaneous transluminal coronary angioplasty (PTCA) o r coronary artery bypass graft surgery (CABG), should these interventions b e needed. METHODS The 1,506 hospitals participating in the National Registry of Myoca rdial Infarction 2 were classified according to their highest level of inva sive capability: 1) none (noninvasive, 28.1%); 2) coronary arteriography (c ath-capable, 25.2%); 3) coronary angioplasty (PTCA-capable, 7.4%); and 4) b ypass surgery (CABG-capable, 39.2%). Treatment and in-hospital outcomes wer e assessed for 305,812 patients admitted from June 1994 through October 199 6. Follow-up through 90 days uas ascertained in a subset of 30,402 patients enrolled simultaneously in both the National Registry of Myocardial Infarc tion (NRMI) 2 and the Cooperative Cardiovascular Project (CCP). RESULTS The proportion of patients receiving initial reperfusion interventi on was only slightly higher at the more invasive hospitals (noninvasive 32. 5%, cath-capable 31.2%, PTCA-capable 32.9% and CABG-capable 35.9%, p < 0.00 1 by chi-square statistic). Among thrombolytic recipients, median door-to-d rug time interval differed little among hospital types and ranged from 42 t o 45 minutes. At cath-capable, PTCA-capable and CABG-capable hospitals, cor onary arteriography was performed in 32.9%, 37.4% and 64.9%, respectively, and PTCA in 0.0%, 5.1% and 31.4%, both p < 0.001 by chi-square statistic. T he proportion of patients transferred out to other facilities was 51.0%, 42 .2%, 39.9% and 4.4% (p < 0.0001) among noninvasive, cath-capable, PTCA-capa ble and CABG-capable hospitals, respectively. Among patients in the combine d NRMI and CCP data set, mortality at 90 days postinfarction was similar am ong patients initially admitted to each of the four hospital types. CONCLUSIONS Although patients with AMI admitted to hospitals without invasi ve cardiac facilities have a high likelihood of subsequent transfer to othe r facilities, their likelihood of receiving a reperfusion intervention at t he first hospital, their door to thrombolytic drug intervals and their 90-d ay survival rates are similar to those of patients initially admitted to mo re invasively equipped hospitals. These data suggest that a policy of initi al treatment of myocardial infarction at the closest medical facility is ap propriate medical practice. (J Am Coll Cardiol 2000;35:371-9) (C) 2000 by t he American College of Cardiology.