Prognostic Implications of Door-to-Balloon Time and Onset-to-Door Time on Mortality in Patients With ST-Segment–Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

Background: In patients with ST-segment–elevation myocardial infarction, timely reperfusion therapy with door-to-balloon (D2B) time <90 minutes is recommended by the current guidelines. However, whether further shortening of symptom onset-to-door (O2D) time or D2B time would enhance survival of patients with ST-segment–elevation myocardial infarction remains unclear. Therefore, the current study aimed to evaluate the prognostic impact of O2D or D2B time in patients with ST-segment–elevation myocardial infarction who underwent primary percutaneous coronary intervention. Methods and Results: We analyzed 5243 patients with ST-segment–elevation myocardial infarction were treated at 20 tertiary hospitals capable of primary percutaneous coronary intervention in Korea. The association between O2D or D2B time with all-cause mortality at 1 year was evaluated. The median O2D time was 2.0 hours, and the median D2B time was 59 minutes. A total of 92.2% of the total population showed D2B time ≤90 minutes. In univariable analysis, 1-hour delay of D2B time was associated with a 55% increased 1-year mortality, whereas 1-hour delay of O2D time was associated with a 4% increased 1-year mortality. In multivariable analysis, D2B time showed an independent association with mortality (adjusted hazard ratio, 1.90; 95% CI, 1.51–2.39; P<0.001). Reducing D2B time within 45 minutes showed further decreased risk of mortality compared with D2B time >90 minutes (adjusted hazard ratio, 0.30; 95% CI, 0.19–0.42; P<0.001). Every reduction of D2B time by 30 minutes showed continuous reduction of 1-year mortality (90 to 60 minutes: absolute risk reduction, 2.4%; number needed to treat, 41.9; 60 to 30 minutes: absolute risk reduction, 2.0%; number needed to treat, 49.2). Conclusions: Shortening D2B time was significantly associated with survival benefit, and the survival benefit of shortening D2B time was consistently observed, even <60 to 90 minutes.