Impact of infarct-related artery patency before primary PCI on outcome in patients with ST-segment elevation myocardial infarction: The HORIZONS-AMI trial

Aims: We assessed the impact of early infarct-related artery (IRA) recanalisation on the outcomes of patients in the recently conducted, large-scale, multicentre HORIZONS-AMI trial. Methods and results: Of the 3,602 patients enrolled in the HORIZONS-AMI trial, 3,093 patients (85.9%) were treated with percutaneous coronary intervention (PCI) to a single artery. We analysed one-year outcomes in these patients according to the presence or absence of early IRA patency, defined as Thrombolysis in Myocardial Infarction (TIMI) 2 or 3 flow in the IRA. Baseline coronary angiography showed early IRA patency in 1,121 patients (36.2%), while 1,972 patients (63.8%) had TIMI 0 or 1 flow. The presence compared with the absence of early IRA patency was associated with better angiographic results after primary PCI with more TIMI 3 flow after PCI (93.2% vs. 82.9%, p<0.0001) and myocardial blush grade 2 or 3 (84.4% vs. 71.1%, p<0.0001). Early IRA patency was associated with lower rates of one-year mortality (2.5% vs. 3.9%, p=0.04) and definite or probable stent thrombosis (2.0% vs. 4.0%, p=0.002). In multivariable analysis, early IRA patency at baseline angiography was an independent predictor of reduced mortality at one year (HR 0.58, 95% CI: 0.36-0.98, p=0.02). Conclusions: Early IRA patency in patients with STEMI undergoing primary PCI is associated with better TIMI flow and myocardial blush post PCI and is an independent predictor of lower one-year mortality. ClinicalTrials.gov identifier NCT00433966.