Studies Address Improving Door-to-Balloon Times for STEMI Patients

September 18, 2013—B. Hadley Wilson, MD, et al published a study that sought to demonstrate that a network approach to transferring ST-segment elevation myocardial infarction (STEMI) patients can achieve durable first door-to-balloon (D2B) times for percutaneous coronary intervention (PCI) within 90 minutes. The investigators noted that nationally, the minority of STEMI cases achieve first D2B times < 2 hours from referral centers, with even fewer in < 90 minutes. The study is available online ahead of print in the Journal of the American College Cardiology (JACC): Cardiovascular Interventions.

As summarized in JACC: Cardiovascular Interventions, the study included STEMI patients who were transferred from nine network hospitals in 2007 compared with those in 2008 to 2011 after installing the following initiatives: (1) establishing a hospital referral system, (2) goal-oriented performance protocols, (3) expedited transport by ground or air, (4) first hospital activation of the PCI hospital catheterization laboratory, and (5) outreach coordinator and patient-level web-based feedback to the referring hospital.

The investigators reported that a total of 101 STEMI patients transported in 2007 were compared with 442 STEMI patients transferred after starting these initiatives for STEMI from 2008 to 2011, with the median door-in to door-out time decreasing from 44 to 35 minutes (P < .0001), the median first D2B time decreasing from 109.5 to 88 minutes (P < .0001), and the percentage under 90 minutes increasing from 22.8% to 55.9% (P < .0001).

Overall, throughout the study period (2007–2011), the transport times remained consistent with a median 36.5 minutes versus 36 minutes (P = .98), whereas the PCI hospital D2B time decreased from 20 to 16 minutes (P < .0001). Length of stay and in-hospital mortality remained low at 3 days and < 4%, respectively. These findings demonstrated that system-wide network programs can achieve sustained (> 4 years) first D2B times of < 90 minutes, concluded the investigators in JACC: Cardiovascular Interventions.

In other research of D2B times, the American College of Cardiology Foundation's National Cardiovascular Database Registry (NCDR) funded a study of D2B times and mortality among patients undergoing primary PCI. The findings were published by Daniel S. Menees, MD, et al on September 5, 2013, in the New England Journal of Medicine (2013;369:901–909).

The NCDR study found that although national D2B times have significantly improved for patients undergoing primary PCI for STEMI, in-hospital mortality has remained virtually unchanged. The data suggest that additional strategies are needed to reduce in-hospital mortality in this population, concluded the investigators.

As summarized in the New England Journal of Medicine, the investigators analyzed annual trends in D2B times and in-hospital mortality using data from 96,738 admissions for patients undergoing primary PCI for STEMI from July 2005 through June 2009 at 515 hospitals participating in the NCDR's CathPCI Registry. In a subgroup analysis using a linked Medicare dataset, they assessed the 30-day mortality rates.

According to the investigators, the median D2B times significantly declined from 83 minutes in the 12 months from July 2005 through June 2006 to 67 minutes in the 12 months from July 2008 through June 2009 (P < .001). Similarly, the percentage of patients for whom the D2B time was 90 minutes or less increased from 59.7% in the first year to 83.1% in the last year (P < .001). Despite improvements in D2B times, there was no significant overall change in unadjusted in-hospital mortality (4.8% in 2005–2006 and 4.7% in 2008–2009; P = .43 for trend) or in risk-adjusted in-hospital mortality (5% in 2005–2006 and 4.7% in 2008–2009; P = .34), nor was a significant difference observed in unadjusted 30-day mortality (P = .64), reported the investigators in the New England Journal of Medicine.