Importance: In-hospital ST-segment elevation myocardial infarction (STEMI) is a unique clinical entity with epidemiology, incidence, and outcomes distinct from that of out-of-hospital STEMI and has only within the past 10 years begun to receive increased attention and research. Patients with in-hospital STEMI are older, have more comorbidities, and more frequently have coagulopathies and contraindications for anticoagulation and fibrinolytic therapy. A standardized clinical definition of in-hospital STEMI is lacking. The objectives of this special communication are to (1) summarize the knowledge base regarding in-hospital STEMI; (2) review the challenges of diagnosis and treatment of patients with in-hospital STEMI; (3) present a standardized clinical definition for in-hospital STEMI; and (4) provide a quality improvement protocol to improve diagnosis, triage, and treatment of patients with in-hospital STEMI.
Observations: Patients with in-hospital STEMI less frequently present with typical angina symptoms, and an electrocardiogram is often obtained owing to changes in clinical status, changes on telemetry, or a finding of elevated cardiac biomarker. The frequent nontypical presentations often lead to substantial delays in the diagnosis of STEMI. Only 34% to 71% of patients with in-hospital STEMI undergo diagnostic catheterization, and only 22% to 56% undergo percutaneous coronary intervention. Even in contemporary reports, some studies report in-hospital mortality in the range of 31% to 42%. Three areas of delay in the treatment of patients with in-hospital STEMI that merit particular attention are (1) delays in electrocardiogram acquisition, (2) delays in electrocardiogram interpretation, and (3) delays in activation of existing STEMI systems of care.
Conclusions and relevance: Treatment of patients with in-hospital STEMI is more complex and challenging than treatment of patients who develop out-of-hospital STEMI, leading to delays in diagnosis and triage and less frequent use of reperfusion therapy. Quality improvement programs targeted at decreasing delays and streamlining treatment of such patients may improve treatment and outcome.