Relation of Pain-to-Balloon Time and Mortality in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Limited and inconsistent data are present regarding the importance of the time delay between symptom onset and balloon inflation in ST-segment elevation myocardial infarction (STEMI) patients. We aimed to investigate the possible influence of prolonging pain-to-balloon times (PBT) on in-hospital outcomes and mortality in a large cohort of patients with STEMI undergoing primary percutaneous coronary intervention. We retrospectively studied 2,345 STEMI patients (age 61 ± 13 years, 82% men) who underwent primary percutaneous coronary intervention. Patients were stratified according to PBT into 3 groups: ≤120 minutes, 121 to 360 minutes, and >360 minutes. Patients' records were assessed for the occurrence of in-hospital complications, 30-day, and 1-year mortality. Of the 2,345 study patients, 36% had PBT time ≤120 minutes, 40% had PBT of 121 to 360 minutes and 24% had PBT time >360 minutes. The major part of the total PBT (average 358 minutes) was caused by the time interval from symptom onset to hospital arrival, namely, pain-to-door time (average 312 minutes) in all 3 groups. Longer PBT was associated with a lower left ventricular ejection fraction, higher incidence of in-hospital complications, and higher 30-day mortality. In 2 multivariate cox regression models, a per-hour increase in PBT (hazard ratio 1.03 [95% confidence interval 1.00 to 1.06], p = 0.039) as well as PBT >360 minutes (hazard ratio 1.6 [95% confidence interval 1.1 to 2.5], p = 0.04) were both independently associated with an increased risk for 1-year mortality. In conclusion, PBT may be an accurate and independent marker for adverse events, pointing to the importance of coronary reperfusion as early as possible based on the onset of pain.