Mortality implications of primary percutaneous coronary intervention treatment delays: insights from the Assessment of Pexelizumab in Acute Myocardial Infarction trial.

BACKGROUND

Prior studies demonstrate a direct relationship between treatment delays to primary percutaneous intervention and mortality in patients with ST-segment elevation myocardial infarction (STEMI). This analysis compared the relationship of symptom onset-to-balloon time and door-to-balloon time on mortality in patients with STEMI.

METHODS AND RESULTS

We analyzed different treatment delays (symptom onset-to-balloon time, door-to-balloon time) and mortality in 5745 STEMI patients. Baseline characteristics, flow grade, 90-day mortality, and clinical outcomes were compared in patients stratified by treatment delay. Multivariable logistic regression modeling was performed to assess the independent and relative effect of each treatment delay on 90-day mortality. Female sex, increased age, and worse thrombolysis in myocardial infarction flow grade were significantly associated with longer symptom onset-to-balloon times and door-to-balloon times. Longer symptom onset-to-balloon time was significantly associated with worse 90-day mortality (3.7%, 4.2%, and 6.5% for time delays <3 hours, 3 to 5 hours, and >5 hours, respectively, P<0.0001). Similarly, longer door-to-balloon times were significantly associated with worse 90-day mortality (3.2%, 4.0%, 4.6%, and 5.3% for delays <60 minutes, 60 to 90 minutes, 90 to 120 minutes, and ≥120 minutes respectively, P<0.0001). In a multivariate model of 90-day mortality, door-to-balloon time (χ(2) 6.0, P<0.014), and symptom onset-to-hospital arrival (χ(2) 9.8, P<0.007) remained independent determinants.

CONCLUSIONS

Both symptom onset-to-balloon time and hospital door-to-balloon time are strongly associated with 90-day mortality following STEMI. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00091637.