Frequency of Nonsystem Delays in ST-Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention and Implications for Door-to-Balloon Time Reporting (from the American Heart Association Mission: Lifeline Program)

The percentage of patients with primary percutaneous coronary intervention (PCI) with door-to-balloon (D2B) times ≤90 minutes is used as a hospital performance measure for public reporting. Patients can be excluded from reporting for nonsystem-related delays. How exclusions impact D2B time reporting at the hospital level is unknown. The percentage of patients having nonsystem delays for primary PCI at the hospital level was calculated using data from the Acute Coronary Treatment Intervention Outcomes Network Registry-Get with the Guidelines Registry. Hospitals were categorized based on tertiles of percentage of excluded patients: low, ≤7.1%; intermediate, >7.1% to 11.2%; and high, >11.2%. From January 1, 2007, to March 31, 2011, 43,909 patients from 294 hospitals were included. The percentage of exclusions differed substantially among hospitals (0% to 68%, median 9.2% [interquartile range 5.6% to 13.5%]). Exclusion reasons included vascular access difficulty (7.6%), cardiac arrest/intubation (38%), and PCI procedural difficulties (20%). Including patients with nonsystem delays significantly increased D2B times by ≤2 minutes for each group. The effect was larger on the proportion of patients having a D2B ≤90 minutes (low 83.6% to 85%, intermediate 82.9% to 86.3%, high 82% to 87.5%, p <0.001, for all). If a criterion of having ≥90% of patients with D2B ≤90 minutes was used, excluding patients with nonsystem delays significantly increased the proportion of patients meeting this goal for each group: low, 28% to 37%; intermediate, 17.7% to 37.5%; and high, 14% to 52% (all p <0.01). In conclusion, the proportion of patients excluded from D2B reporting varies substantially among hospitals. This has a greater impact on percentage of patients with D2B time ≤90 minutes than on median D2B times.