National Registry Analyzes Nonsystem Reasons for Delays in Door-to-Balloon Times and Mortality

April 16, 2013—A report from the National Cardiovascular Data Registry that seeks to characterize nonsystem reasons for delay in door-to-balloon (DTB) time and the impact on in-hospital mortality has been published by Rajesh V. Swaminathan, MD, et al in the Journal of the American College of Cardiology (2013;61:1688–1695). Nonsystem reasons for delay in DTB time in ST-segment elevation myocardial infarction (STEMI) patients presenting for primary percutaneous coronary intervention are common and associated with high in-hospital mortality, concluded the investigators.

According to the investigators, studies have evaluated predictors of delay in DTB time, highlighting system-related issues and patient demographic characteristics; however, limited data exist for nonsystem reasons for delay in DTB time.

As summarized in the Journal of the American College of Cardiology, the investigators analyzed nonsystem reasons for delay in DTB time among 82,678 ST-segment elevation myocardial infarction patients who underwent primary percutaneous coronary intervention within 24 hours of symptom onset in the CathPCI Registry from January 1, 2009 to June 30, 2011.

The investigators found that nonsystem delays occurred in 14.7% of patients (n = 12,146). Patients with nonsystem delays were more likely to be older, female, African-American, and have greater comorbidities. The in-hospital mortality for patients treated without delay was 2.5% versus 15.1% for those with delay (P < .01). Nonsystem delay reasons included delays in providing consent (4.4%), difficult vascular access (8.4%), difficulty crossing the lesion (18.8%), “other” (31%), and cardiac arrest/intubation (37.4%).

Cardiac arrest/intubation delays had the highest in-hospital mortality (29.9%), despite the shortest time delay (median DTB time: 84 min; 25th to 75th percentile: 64 to 108 min); delays in providing consent had a relatively lower in-hospital mortality rate (9.4%), despite the longest time delay (median DTB time: 100 min; 25th to 75th percentile: 80 to 131 min). Mortality for delays due to difficult vascular access, difficulty crossing a lesion, and “other” was also higher (8%, 5.6%, and 5.9%, respectively) compared with nondelayed patients (P < .0001). After adjustment for baseline characteristics, in-hospital mortality remained higher for patients with nonsystem delays, reported the investigators in the Journal of the American College of Cardiology.