ST Elevation Myocardial Infarction Diagnosed after Hospital Admission

Abstract

Background—Treatment times for ST-elevation myocardial infarction (STEMI) patients presenting to percutaneous coronary intervention (PCI) hospitals have improved dramatically over the last 10 years, particularly for patients using emergency medical services (EMS). Limited data exist regarding treatment times and outcomes for patients who develop STEMI after hospital admission.

Methods and Results—Using a comprehensive prospective regional STEMI program database, we evaluated characteristics and outcomes for patients who develop STEMI after hospital admission. Of the 3,795 consecutive STEMI patients treated using the Minneapolis Heart Institute regional STEMI program from March 2003 to January 2013, 990 (26.1%) presented initially to the PCI facility, including 640 arriving via EMS, 267 self/family driven, and 83 already admitted to the hospital. Patients with in-hospital presentation were older with higher BMIs, were more likely to have hypertension and present with pre-PCI cardiac arrest and cardiogenic shock. Door-to-balloon times (diagnostic EKG-to-balloon for in-hospital patients) were longer than EMS patients (76 vs. 51 minutes; p<0.001), but similar to self/family driven patients (76 vs. 66 minutes; p=0.13). In-hospital patients had longer lengths-of-stay (LOS) (5 vs. 3 vs. 3 days; p<0.001) and higher 1-year mortality (16.9% vs. 10.3% vs. 7.1%; p=0.032). These patients frequently had high-risk and complex reasons for admission including 30.1% with acute coronary syndrome, 24.1% post-surgery, 12.1% respiratory failure and 8.4% ventricular fibrillation.

Conclusions—Patients who develop STEMI while in-hospital represent a unique, high-risk subset of patients. They have increased treatment time and LOS and higher mortality than those presenting via EMS or who are self/family driven.