“ST-Elevation Myocardial Infarction Diagnosed After Hospital

To the Editor: We read with interest the recent report by Garberich et al describing data from a single-center registry of patients diagnosed with ST-segment–elevation myocardial infarction (STEMI) after hospital admission. This study confirmed that hospitalized patients who develop STEMI are older and have increased comorbidities, time to perfusion, and mortality compared with outpatients with STEMI. Inpatient STEMI is increasingly being recognized as an important challenge for optimizing acute coronary syndrome care, and we would like to highlight 3 important issues raised by the study by Garberich et al. First, patients who developed STEMI while hospitalized with a primary cardiac diagnosis had better outcomes than patients initially admitted with a noncardiac diagnosis. Their study showed an 8-fold difference in mortality at 30 days (2.0% versus 17.7%; P=0.012) and a 5-fold difference at 1 year (6.1% versus 32.4%; P=0.002). We previously reported high in-hospital mortality rates in patients who developed STEMI while hospitalized for a noncardiac reason, both at our hospital (39.6% [inpatient] versus 3.9% [outpatient]; P<0.001) and in the 2008 to 2011 California State Inpatient Database (32.7% versus 12.9%; P<0.001). Although Garberich et al reported overall lower mortality rates than in our studies, it is important to note that >90% of the patients in their study underwent primary percutaneous coronary intervention and that 54% of the patients in their study were admitted with a primary cardiac diagnosis. In our studies, we found that 30% to 70% of inpatients with STEMI were deemed not to be candidates for coronary angiography for various reasons and that these patients have a much higher mortality. The present study, along with published data, presents a compelling picture that the development of STEMI in a patient hospitalized for a noncardiac condition is a lethal disease. Second, multiple studies have now reported significant differences between patients who develop inpatient and outpatient STEMI. Patients who develop inpatient STEMI are older, often have atypical clinical presentation, and have more comorbidities. These patients are less likely to be recognized in a timely manner and to have longer ECG-to-reperfusion times. Third, Garberich et al reported that implementation of a “level 1 MI program,” a standard STEMI protocol for in-hospital STEMI, resulted in an important reduction in in-hospital mortality (from 15.4% to 5.3%, a 10.1% absolute and 66% relative reduction) with a moderate decrease in median reperfusion times (from 85 to 67 minutes). These data demonstrate that systems designed to improve the care of inpatient STEMI can have a significant beneficial impact on mortality. We congratulate the authors on this important finding. In our center, we have implemented a healthcare system–wide educational campaign to improve the awareness among staff of noncardiac units of the importance of early recognition of clinical signs of MI, early ECG acquisition, and rapid ECG interpretation and have formed a cardiac response team as key elements to improve inpatient STEMI care.