001 Long-term outcomes of patients with ST-elevation myocardial infarction with and without reperfusion therapy: Results of a systematic province-wide field evaluation in Québec

Reperfusion treatment of patients with ST-elevation myocardial infarction (STEMI) reduces short-term morbidity and mortality. However, there is little real-world data on long-term benefits of reperfusion treatment. This province-wide field evaluation of STEMI care with linkage to Québec's medico-administrative databases analyzed clinical outcomes out to 3 years. The medical charts of all patients who presented with symptoms of myocardial infarction to 80 hospitals that treat over 95% of such patients were reviewed to identify STEMI patients. STEMI was confirmed by core laboratory analysis of the presenting ECG. Data about patient characteristics, process of care and treatment delays were entered in a centralized website. For follow-up to 3 years, medical insurance numbers were linked to medico-administrative data recording all hospitalisations and revascularization procedures as well as to Québec's central death registry. There were 2035 patients with definite STEMI or left bundle branch block. Of these, 23% (n = 469) were classified as not having received reperfusion therapy because they did not receive fibrinolysis and were not sent for primary angioplasty within 4 hours. The remainder (1566 patients; 77%) were considered to have received reperfusion therapy (fibrinolysis, 22%; primary angioplasty at the first hospital, 26%; primary angioplasty after transfer, 51%). At 3 years of follow-up, 39% (n = 184) of patients without reperfusion treatment had died compared to 12% of patients with reperfusion treatment (RR = 3.23; 95% CI, 2.72-3.85). The mortality difference occurred primarily in the first few months after STEMI after which the survival curves remained largely parallel. Reperfused patients also had lower hospitalization rates for heart failure (4.4% versus 13.2%, respectively; RR = 3.00; 95% CI, 2.16-4.16) and for reinfarction (4.9% versus 7.2%, respectively; RR = 1.47; 95% CI, 1.00-2.18). This systematic evaluation of STEMI care with long term follow-up indicates that the substantial benefits of reperfusion treatment are sustained at 3 years. The parallelism of survival curves after 3 months suggests that the higher mortality in non-reperfused patients may relate more to absence of reperfusion treatment rather than to the baseline imbalances between reperfused and non-reperfused patients. These results highlight the importance of lowering rates of non-reperfusion in patients with STEMI.