Reporting trends and outcomes in ST-segment-elevation myocardial infarction national hospital quality assessment programs.

BACKGROUND: For patients who undergo primary percutaneous coronary intervention (PCI) for ST-segment-elevation myocardial infarction, the door-to-balloon time is an important performance measure reported to the Centers for Medicare & Medicaid Services (CMS) and tied to hospital quality assessment and reimbursement. We sought to assess the use and impact of exclusion criteria associated with the CMS measure of door-to-balloon time in primary PCI.

METHODS AND RESULTS: All primary PCI-eligible patients at 3 Massachusetts hospitals (Brigham and Women's, Massachusetts General, and North Shore Medical Center) were evaluated for CMS reporting status. Rates of CMS reporting exclusion were the primary end points of interest. Key secondary end points were between-group differences in patient characteristics, door-to-balloon times, and 1-year mortality rates. From 2005 to 2011, 26% (408) of the 1548 primary PCI cases were excluded from CMS reporting. This percentage increased over the study period from 13.9% in 2005 to 36.7% in the first 3 quarters of 2011 (P<0.001). The most frequent cause of exclusion was for a diagnostic dilemma such as a nondiagnostic initial ECG, accounting for 31.2% of excluded patients. Although 95% of CMS-reported cases met door-to-balloon time goals in 2011, this was true of only 61% of CMS-excluded cases and consequently 82.6% of all primary PCI cases performed that year. The 1-year mortality for CMS-excluded patients was double that of CMS-included patients (13.5% versus 6.6%; P<0.001).

CONCLUSIONS: More than a quarter of patients who underwent primary PCI were excluded from hospital quality reports collected by CMS, and this percentage has grown substantially over time. These findings may have significant implications for our understanding of process improvement in primary PCI and mechanisms for reimbursement through Medicare.