Defining Heart Failure End Points in ST-Segment Elevation Myocardial Infarction Trials

Abstract

Mortality rates for patients with acute myocardial infarction (MI) continue to decline as evidence-based therapies are implemented on a broader scale, invasive management and revascularization are more widely used, and reperfusion times for patients with acute ST-segment elevation myocardial infarction (STEMI) are shortened.1,2 Recent data from the Acute Coronary Treatment and Intervention Outcomes Network Registry–Get With the Guidelines (ACTION Registry-GWTG) in the United States demonstrated that, by 2009, risk-adjusted in-hospital mortality had decreased to 5.5% among STEMI patients treated in routine practice.3 In addition, mortality rates through and beyond 1 year among STEMI patients treated with primary percutaneous coronary intervention (PCI) enrolled in recent clinical trials have declined by 3% to 6%.4,5 Yet, improvements in survival demonstrated with STEMI patients may be tempered by the consequent morbidity of postinfarction heart failure (HF), which, unfortunately remains a common clinical event.6 Acute STEMI is an independent predictor of HF at admission, and the development of HF among STEMI patients is associated with a much higher long-term mortality rate compared with patients who do not develop HF.7 Because mortality rates for STEMI patients have declined and reinfarction rates have been shown to be low with the widespread use of primary PCI, attention has shifted toward reducing postinfarction HF because this outcome is thought to reflect the downstream impact of acute therapies for STEMI. There are multiple convergent trends that could contribute to the rising prevalence of HF after STEMI, including an aging population and a decrease in sudden cardiac death because of defibrillator therapy. Fortunately, though, HF hospitalizations are declining nationwide,8 partially because of a declining risk of postinfarction HF.9,10 Given that ischemic heart disease is the most common cause of HF,11 the relationship of improvements in upstream treatment …