(PCI) leads to more rapid and sustained infarct-related artery patency, and has become widely accepted as the optimal reperfusion modality in STEMI. It has also been suggested that STR may be inversely related to infarct size, and can be used to compare the relative efficacy of different therapies at the time of PCI.3 In this regard, STR has the advantage of being noninvasive, inexpensive, and is easy to apply widely. 4 Few studies, however, have examined the impact of STR after PCI on late survival.Background-In patients with ST-segment elevation myocardial infarction undergoing thrombolytic therapy, the degree of ST-segment resolution (STR) correlates with long-term cardiovascular mortality. The long-term predictive value of STR after primary percutaneous coronary intervention (PCI) is less well understood. We sought to determine the long-term prognostic value of STR after primary PCI in ST-segment-elevation myocardial infarction.
Methods and Results-In a formal substudy from the Harmonizing Outcomes with Revascularization and Stents inAcute Myocardial Infarction (HORIZONS-AMI) trial, 2484 patients with ST-segment-elevation myocardial infarction undergoing primary PCI with interpretable baseline and 60-minute post-PCI electrocardiograms had at least 1 mm of baseline ST-segment elevation in ≥2 contiguous leads. Patients were categorized by the degree of STR at 60 minutes:(1) complete (>70%); (2) partial (30%-70%); and (3) absent (<30%). Absent, incomplete, and complete STR were achieved in 514 (20.7%), 712 (28.7%), and 1258 (50.5%) patients, respectively. STR <30% was associated with a greater likelihood of hypertension, diabetes mellitus, longer symptom onset to balloon time, lower left ventricular ejection fraction, and final thrombolysis in myocardial infarction flow <3. At 3 years, patients with STR<30% experienced a higher rate of major adverse cardiovascular events (death, reinfarction, ischemia-driven target vessel revascularization or stroke; 29.9% versus 20.1% versus 19.6%; P<0.0001), ischemia-driven target vessel revascularization (20.4% versus 14.0% versus 11.7%; P<0.001), and mortality (8.4% versus 5.0% versus 5.6%; P=0.03) than those with partial and complete STR, respectively. By multivariable analysis, STR<30% was an independent predictor of 3-year major adverse cardiovascular events (hazard ratio, 1.58; 95% confidence interval, 1.24-2.00; P=0.0002) and 3-year ischemia-driven target vessel revascularization (hazard ratio, 1.87; 95% confidence interval, 1.41-2.48; P<0.0001). Conclusions-In this large international study, absent STR 60 minutes after primary PCI was present in ≈1 in 5 patients with ST-segment-elevation myocardial infarction and was a significant independent predictor of major adverse cardiovascular events and target vessel revascularization at 3 years. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00433966 (Circ Cardiovasc Interv. 2013;6:216-223.)