Weaver, W. Douglas

Background: Randomized clinical trials are often criticized for not reflecting real-world practice. To understand the effect of site and patient selection on trial generalizability, we examined US patient and hospital participation within the Dual Antiplatelet Therapy (DAPT) Study, a broadly inclusive trial of PCI patients, using a linked analysis with the CathPCI Registry®. Methods: Within the CathPCI Registry, we identified patients undergoing PCI between September 1, 2009 and July 1, 2011 - the period of DAPT Study enrollment. We compared US patients enrolled in DAPT to CathPCI Registry patients meeting DAPT inclusion criteria. Characteristics of US DAPT sites were also compared to those of hospitals not participating in DAPT. Standardized differences (%) for all variables were estimated, with those greater than 10% considered significant. Results: Among 1,139,932 NCDR patients undergoing PCI, 748374 (65.7%) met the enrollment criteria for DAPT, and 23495 (2.1%) were enrolled. Enrolled patients were younger and had lower rates of prior stroke, CHF and peripheral vascular disease, but were similar with respect to race and gender compared with eligible patients (Table). Of the 1276 hospitals within the NCDR, 309 (24.2%) participated in DAPT. Hospital characteristics differed markedly, with DAPT-participating hospitals being larger (mean beds 468 vs. 311), more often located in urban settings (61.2% vs. 42.6%), more often affiliated with training programs (53.7% vs. 34.1%), and with higher annual PCI volumes (mean annual hospital volume 858 vs. 378 PCIs) compared with non-DAPT hospitals. Conclusions: While liberal inclusion criteria may allow randomized trials to better simulate “real-world” clinical practice, the process of site selection may encourage participation of higher volume, urban hospital settings. These findings are relevant to clinical trial interpretation and implementation of evidence-based practice throughout the healthcare system.

Background— Post-percutaneous coronary intervention (PCI) bleeding complications are an important quality metric. We sought to characterize site-level variation in post-PCI bleeding and explore the influence of patient and procedural factors on hospital bleeding performance. Methods and Results— Hospital-level bleeding performance was compared pre- and postadjustment using the newly revised CathPCI Registry ® bleeding risk model (c-index, 0.77) among 1292 National Cardiovascular Data Registry ® hospitals performing >50 PCIs from 7/2009 to 9/2012 (n=1 984 998 procedures). Using random effects models, outlier sites were identified based on 95% confidence intervals around the hospital’s random intercept. Bleeding 72 hours post-PCI was defined as: arterial access site, retroperitoneal, gastrointestinal, or genitourinary bleeding; intracranial hemorrhage; cardiac tamponade; nonbypass surgery–related blood transfusion with preprocedure hemoglobin ≥8 g/dL; or absolute decrease in hemoglobin value ≥3 g/dL with preprocedure hemoglobin ≤16 g/dL. Overall, the median unadjusted post-PCI bleeding rate was 5.2% and varied among hospitals from 2.6% to 10.4% (5th, 95th percentiles). Center-level bleeding variation persisted after case-mix adjustment (2.8%–9.5%; 5th, 95th percentiles). Although hospitals’ observed and risk-adjusted bleeding ranks were correlated (Spearman ρ: 0.88), individual rankings shifted after risk-adjustment (median Δ rank order: ±91.5; interquartile range: 37.0, 185.5). Outlier classification changed postadjustment for 29.3%, 16.1%, and 26.5% of low-, non-, and high-outlier sites, respectively. Hospital use of bleeding avoidance strategies (bivalirudin, radial access, or vascular closure device) was associated with risk-adjusted bleeding rates. Conclusions— Despite adjustment for patient case-mix, there is wide variation in rates of hospital PCI-related bleeding in the United States. Opportunities may exist for best performers to share practices with other sites.

Aims: The NCDR CathPCI Registry collects detailed clinical, process-of-care and outcomes data for patients undergoing coronary angiography and percutaneous coronary intervention (PCI) in the USA. The registry contributes to quality of care by providing data feedback on a wide range of performance metrics to participating centres and by facilitating local and national quality improvement efforts. Interventions: No treatments are mandated, participating centres receive routine quality-of-care and outcomes performance feedback reports and access to a quality dashboard for personalized performance reports. Population: Patients undergoing cardiac catheterization and PCI are retrospectively identified. No informed consent is required, as data are anonymised. From inception in 1998, more than 12 million records have been submitted from 1577 participating US centres. Baseline data: Approximately 250 fields encompassing patient demographics, medical history and risk factors, hospital presentation, initial cardiac status, procedural details, medications, laboratory values, and in-hospital outcomes. Linkages with outside sources of data have permitted longitudinal outcomes assessment in some cases. Centre personnel enter the data into the registry, in some cases facilitated by software vendors. There are non-financial incentives for centre participation. Data completeness is noteworthy with most fields missing at rates less than 5%. A comprehensive data quality program is employed to enhance data validity. Endpoints: Main outcome measures include quality process metrics and in-hospital patient outcomes. Data are available for research by application to: http://www.ncdr.com

Background— Prior studies demonstrate a direct relationship between treatment delays to primary percutaneous intervention and mortality in patients with ST-segment elevation myocardial infarction (STEMI). This analysis compared the relationship of symptom onset-to-balloon time and door-to-balloon time on mortality in patients with STEMI. Methods and Results— We analyzed different treatment delays (symptom onset-to-balloon time, door-to-balloon time) and mortality in 5745 STEMI patients. Baseline characteristics, flow grade, 90-day mortality, and clinical outcomes were compared in patients stratified by treatment delay. Multivariable logistic regression modeling was performed to assess the independent and relative effect of each treatment delay on 90-day mortality. Female sex, increased age, and worse thrombolysis in myocardial infarction flow grade were significantly associated with longer symptom onset-to-balloon times and door-to-balloon times. Longer symptom onset-to-balloon time was significantly associated with worse 90-day mortality (3.7%, 4.2%, and 6.5% for time delays <3 hours, 3 to 5 hours, and >5 hours, respectively, P <0.0001). Similarly, longer door-to-balloon times were significantly associated with worse 90-day mortality (3.2%, 4.0%, 4.6%, and 5.3% for delays <60 minutes, 60 to 90 minutes, 90 to 120 minutes, and ≥120 minutes respectively, P <0.0001). In a multivariate model of 90-day mortality, door-to-balloon time (χ 2 6.0, P <0.014), and symptom onset-to-hospital arrival (χ 2 9.8, P <0.007) remained independent determinants. Conclusions— Both symptom onset-to-balloon time and hospital door-to-balloon time are strongly associated with 90-day mortality following STEMI. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00091637.