Relationship Between Operator Volume and Adverse Outcome in Contemporary Percutaneous Coronary Intervention Practice An Analysis of a Quality-Controlled Multicenter Percutaneous Coronary Intervention Clinical Database

ObjectivesThe aim of our study was to evaluate the volume-outcome relationship in a large, quality-controlled, contemporary percutaneous coronary interventions (PCI) database.BackgroundWhether the relationship between physician volume of PCI and outcomes still exists in the era of coronary stents is unclear.MethodsData on 18,504 consecutive PCIs performed by 165 operators in calendar year 2002 were prospectively collected in a regional consortium. Operators' volume was divided into quintiles (1 to 33, 34 to 89, 90 to 139, 140 to 206, and 207 to 582 procedures/year). The primary end point was a composite of major adverse cardiovascular events (MACE) including death, coronary artery bypass grafting, stroke or transient ischemic attack, myocardial infarction, and repeat PCI at the same site during the index hospital stay.ResultsThe unadjusted MACE rate was significantly higher in quintiles one and two of operator volume when compared with quintile five (7.38% and 6.13% vs. 4.15%, p = 0.002 and p = 0.0001, respectively). A similar trend was observed for in-hospital death. After adjustment for comorbidities, patients treated by low volume operators had a 63% increased odds of MACE (adjusted odds ratio [OR] 1.63, 95% confidence interval [CI] 1.29 to 2.06, p < 0.0001 for quintile [Q]1; adjusted OR 1.63, 95% CI 1.34 to 1.90, p < 0.0001 for Q2 vs. Q5), but not of in-hospital death. Overall, high volume operators had better outcomes than low volume operators in low-risk and high-risk patients.ConclusionsAlthough the relationship between operator volume and in-hospital mortality is no longer significant, the relationship between volume and any adverse outcome is still present. Technological advancements have not yet completely offset the influence of procedural volume on proficiency of PCIs

Dirac cohomology, elliptic representations and endoscopy

The first part (Sections 1-6) of this paper is a survey of some of the recent developments in the theory of Dirac cohomology, especially the relationship of Dirac cohomology with (g,K)-cohomology and nilpotent Lie algebra cohomology; the second part (Sections 7-12) is devoted to understanding the unitary elliptic representations and endoscopic transfer by using the techniques in Dirac cohomology. A few problems and conjectures are proposed for further investigations.Comment: This paper will appear in `Representations of Reductive Groups, in Honor of 60th Birthday of David Vogan', edited by M. Nervins and P. Trapa, published by Springe

The comparative efficacy of bivalirudin is markedly attenuated by use of radial access: insights from Blue Cross Blue Shield of Michigan Cardiovascular Consortium

AIM: The purpose of our study was to evaluate the relative impact of bivalirudin on bleeding outcomes associated with trans-radial interventions (TRI) in real world practice. METHODS AND RESULTS: Data for patients undergoing percutaneous coronary intervention (PCI) between January 2010 and March 2014 at the 47 hospitals participating in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) were utilized. Propensity matching was used within cohorts defined by access site. The impact of bivalirudin use on in-hospital outcomes was evaluated with Fisher\u27s exact tests. Among patients undergoing trans-femoral interventions (TFI), use of bivalirudin was associated with a reduction in bleeding compared with both glycoprotein IIb/IIIa inhibitors (GPI; 1.67 vs. 3.46%, absolute risk reduction (ARR) 1.79%, odds ratio, OR, 0.47, confidence interval, CI, 0.41-0.54, number needed to treat, NNT 56, P \u3c 0.001) and heparin (1.26 vs. 1.76%, ARR 0.5%, OR 0.71, CI 0.61-0.82, NNT 197, P \u3c 0.001). Among patients undergoing TRI, there was a more modest absolute reduction in bleeding with bivalirudin compared with GPI (0.79 vs. 1.41%, ARR 0.62%, OR 0.56, CI 0.34-0.90, NNT 161, P = 0.016) and no difference in bleeding compared with heparin (0.46 vs. 0.46%, OR 1, CI 0.54-1.84, P = 1). CONCLUSION: Bivalirudin is markedly efficacious in reducing bleeding in patients undergoing TFI. The reduction in bleeding associated with bivalirudin use is minimal to absent in patients undergoing TRI. Given its lower cost and comparable outcomes, heparin should be the preferred anticoagulation strategy in those undergoing radial PCI