Abstract 61: Are Door to Balloon Times An Adequate Measure of STEMI Acute Care?

Abstract

Background: Early reperfusion of patients with STEMI, with a target door to balloon (D2B) time < 90 min, is a core measure of acute myocardial infarction treatment. However, it only applies to patients going to the lab emergently. Patients with STEMI may undergo catheterization outside this initial window or may be unrecognized and not undergo catheterization at all. This study was performed to identify patients with an ECG consistent with an acute MI and clarify the reasons they did not undergo catheterization during their admission. Methods: During the period of January- July 2011 all patients with an ECG consistent with STEMI were identified by interrogation of the MUSE computerized ECG system. This list of patients was compared to the list of patients undergoing cardiac catheterization to identify those patients with ECG evidence of STEMI that did not undergo catheterization. This list was analyzed for common factors and to clarify whether care was appropriate and timely. Results: During the observed time period there were 217 patients with STEMI by ECG. Emergency revascularization was requested in 88, with 8 subsequently cancelled. The median D2B time was 60.5 minutes [D2B time from our ED was 62.5 minutes, 43 minutes for transfer patients from arrival time at Stony Brook]. During their admissions 148 of the patients underwent cardiac catheterization; 62 did not undergo catheterization. The single largest (25 patients) subgroup ruled out for myocardial injury; ECGs reflected early repolarization, prior infarction. The 2 nd largest subgroup (15 patients) had serious comorbidities (active GI bleeding 2, intracerebral bleeding/acute CVA 7, sepsis/DIC 3, multiple comorbidities 3). A subgroup of 10 patients refused cardiac catheterization or were DNR/DNI. Myocarditis was diagnosed in 3 patients. The work-up to rule out MI was incomplete in 7 patients. Two patients died in the ED prior to reaching the cath lab. Overall 11 of the 62 patients not undergoing catheterization died. Conclusions: The D2B time is an important quality measure STEMI treatment. However, it is important to ensure that STEMI patients are not being missed and that treatment is not delayed. Comparing all patients with an ECG consistent with STEMI with those undergoing emergent catheterization for STEMI allows opportunities for improvement in the system to be identified and modified and should be a part of the ongoing quality assurance monitoring system.