Safety of Early hospital discharge following admission with ST-elevation myocardial infarction treated with percutaneous coronary intervention: a nationwide cohort study.

Background The Second Primary Angioplasty in Myocardial Infarction (PAMI-II) risk score is recommended by guidelines to identify low-risk patients with ST-elevation myocardial infarction (STEMI) for an early discharge strategy. Aims We aimed to assess the safety of early discharge (≤2 days) for low-risk STEMI treated with primary percutaneous coronary intervention (PCI). Methods Using nationwide data from the SWEDEHEART registry we identified patients with STEMI treated with primary PCI during 2009-2017 of whom 8092 (26.4%) were identified as low risk with the PAMI-II score. Low risk patients were stratified according to their length of hospital stay (≤2 days vs. g2 days) The main endpoint was major adverse cardiovascular events (MACE) including death, reinfarction treated with PCI, stroke or heart failure hospitalization) at one year using a Cox proportional hazard model with propensity score as well as an inverse probability weighting propensity score of average treatment effect to adjust for confounders. Results There were 1449 (17.9%) patients discharged ≤2 days of admission. After adjustment, the 1-year MACE rate were not higher for patients discharged at g2 days from admission than patients discharged ≤2 days (4.3% vs. 3.2%; adjusted HR, 1.31 [95% CI, 0.92-1.87, p=0.14]) and no difference were observed regarding any of the individual components of the main outcome. Results were consistent across all subgroups with no difference in MACE between early and late discharge patients. Conclusions Nationwide observational data suggests that early discharge of low-risk patients with STEMI treated with PCI is not associated with an increase in 1-year MACE.