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Objectives: We sought to create contemporary models for predicting mortality risk following percutaneous coronary intervention (PCI)., Background: There is a need to identify PCI risk factors and accurately quantify procedural risks to facilitate comparative effectiveness research, provider comparisons, and informed patient decision making., Methods: Data from 181,775 procedures performed from January 2004 to March 2006 were used to develop risk models based on pre-procedural and/or angiographic factors using logistic regression. These models were independently evaluated in 2 validation cohorts: contemporary (n = 121,183, January 2004 to March 2006) and prospective (n = 285,440, March 2006 to March 2007)., Results: Overall, PCI in-hospital mortality was 1.27%, ranging from 0.65% in elective PCI to 4.81% in ST-segment elevation myocardial infarction patients. Multiple pre-procedural clinical factors were significantly associated with in-hospital mortality. Angiographic variables provided only modest incremental information to pre-procedural risk assessments. The overall National Cardiovascular Data Registry (NCDR) model, as well as a simplified NCDR risk score (based on 8 key pre-procedure factors), had excellent discrimination (c-index: 0.93 and 0.91, respectively). Discrimination and calibration of both risk tools were retained among specific patient subgroups, in the validation samples, and when used to estimate 30-day mortality rates among Medicare patients., Conclusions: Risks for early mortality following PCI can be accurately predicted in contemporary practice. Incorporation of such risk tools should facilitate research, clinical decisions, and policy applications., (Copyright 2010 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objectives: The objective of this study was to identify preprocedure patient factors associated with percutaneous intervention costs and to examine the impact of these patient factors on economic profiles of interventional cardiologists., Background: There is increasing demand for information about comparative resource use patterns of interventional cardiologists. Economic provider profiles, however, often fail to account for patient characteristics., Methods: Data were obtained from Duke Medical Center cost and clinical information systems for 1,949 procedures performed by 13 providers between July 1, 1997, and December 31, 1998. Patient factors that influenced cost were identified using multiple regression analysis. After assessing interprovider variation in unadjusted cost, mixed linear models were used to examine how much cost variability was associated with the provider when patient characteristics were taken into account., Results: Total hospital costs averaged $15,643 (median, $13,809), $6,515 of which represented catheterization laboratory costs. Disease severity, acuity, comorbid illness and lesion type influenced total costs (R(2) = 38%), whereas catheterization costs were affected by lesion type and acuity (R(2) = 32%). Patient characteristics varied significantly among providers. Unadjusted total costs were weakly associated with provider, and this association disappeared after accounting for patient factors. The provider influence on catheterization costs persisted after adjusting for patient characteristics. Furthermore, the pattern of variation changed: the adjusted analysis identified three new outliers, and two providers lost their outlier status. Only one provider was consistently identified as an outlier in the unadjusted and adjusted analyses., Conclusions: Economic profiles of interventional cardiologists may be misleading if they do not adequately adjust for patient characteristics before procedure.

Objectives: We sought to develop national benchmarks for valve replacement surgery by developing statistical risk models of operative mortality., Background: National risk models for coronary artery bypass graft surgery (CABG) have gained widespread acceptance, but there are no similar models for valve replacement surgery., Methods: The Society of Thoracic Surgeons National Cardiac Surgery Database was used to identify risk factors associated with valve surgery from 1994 through 1997. The population was drawn from 49,073 patients undergoing isolated aortic valve replacement (AVR) or mitral valve replacement (MVR) and from 43,463 patients undergoing CABG combined with AVR or MVR. Two multivariable risk models were developed: one for isolated AVR or MVR and one for CABG plus AVR or CABG plus MVR., Results: Operative mortality rates for AVR, MVR, combined CABG/AVR and combined CABG/ MVR were 4.00%, 6.04%, 6.80% and 13.29%, respectively. The strongest independent risk factors were emergency/salvage procedures, recent infarction, reoperations and renal failure. The c-indexes were 0.77 and 0.74 for the isolated valve replacement and combined CABG/valve replacement models, respectively. These models retained their predictive accuracy when applied to a prospective patient population undergoing operation from 1998 to 1999. The Hosmer-Lemeshow goodness-of-fit statistic was 10.6 (p = 0.225) for the isolated valve replacement model and 12.2 (p = 0.141) for the CABG/valve replacement model., Conclusions: Statistical models have been developed to accurately predict operative mortality after valve replacement surgery. These models can be used to enhance quality by providing a national benchmark for valve replacement surgery.

Objectives: We sought to evaluate the predictive accuracy of four bypass surgery mortality clinical risk models and to examine the extent to which hospitals' risk-adjusted surgical outcomes vary depending on which risk-adjustment method is applied., Background: Cardiovascular "report cards" often compare risk-adjusted surgical outcomes; however, it is unclear to what extent the risk-adjustment process itself may affect these metrics., Methods: As part of the Cooperative Cardiovascular Project's Pilot Revascularization Study, we compared the predictive accuracy of four bypass clinical risk models among 3,654 Medicare patients undergoing surgery at 28 hospitals in Alabama and Iowa. We also compared the agreement in hospital-level risk-adjusted bypass outcome performance ratings depending on which of the four risk models was applied., Results: Although the four risk models had similar discriminatory abilities (C-index, 0.71 to 0.74), certain models tended to overpredict mortality in higher-risk patients. There was high correlation between a hospital's risk-adjusted mortality rates regardless of which of the four models was used (correlation between risk-adjusted rating, 0.93 to 0.97). In contrast, there was limited agreement in which hospitals were identified as "performance outliers" depending on which risk-adjustment model was used and how outlier status was defined., Conclusions: A hospital's risk-adjusted bypass surgery mortality rating, relative to its peers, was consistent regardless of the risk-adjustment model applied, supporting their use as a means of provider performance feedback. Designation of performance outliers, however, can vary significantly depending on the benchmark and methods used for this determination.

Objectives: We compared the acute and one year medical costs and outcomes of coronary stenting with those for balloon angioplasty (percutaneous transluminal coronary angioplasty) in contemporary clinical practice., Background: While coronary stent implantation reduces the need for repeat revascularization, it has been associated with significantly higher acute costs compared with coronary angioplasty., Methods: We studied patients treated at Duke University between September 1995 and June 1996 who received either coronary stent (n = 384) or coronary angioplasty (n = 159) and met eligibility criteria. Detailed cost data were collected initially and up to one year following the procedure. Our primary analyses compared six and 12 month cumulative costs for coronary angioplasty- and stent-treated cohorts. We also compared treatment costs after excluding nontarget vessel interventions; after limiting analysis to those without prior revascularization; and after risk-adjusting cumulative cost estimates., Results: Baseline clinical characteristics were generally similar between the two treatment groups. The mean in-hospital cost for stent patients was $3,268 higher than for those receiving coronary angioplasty ($14,802 vs. $11,534, p < 0.001). However, stent patients were less likely to be rehospitalized (22% vs. 34%, p = 0.002) or to undergo repeat revascularization (9% vs. 26%, p = 0.001) than coronary angioplasty patients within six months of the procedure. As such, mean cumulative costs at 6 months ($19,598 vs. $19,820, p = 0.18) and one year ($22,140 vs. $22,571, p = 0.26) were similar for the two treatments. Adjusting for baseline predictors of cost and selectively examining target vessel revascularization, or those without prior coronary intervention yielded similar conclusions., Conclusions: In contemporary practice, coronary stenting provides equivalent or better one-year patient outcomes without increasing cumulative health care costs.

Objectives: We sought to determine the ability of a treadmill score to provide accurate diagnostic and prognostic risk estimates in women., Background: Treadmill testing has been reported to have a lower accuracy for diagnosis of chest pain in women. The diagnostic and prognostic value of the Duke Treadmill Score (DTS) in women is unknown., Methods: We determined the diagnostic and prognostic value of the DTS in 976 women and 2,249 men who underwent both treadmill testing and cardiac catheterization in a single institution from 1984 to 1994., Results: Women and men differed significantly in DTS (1.6 vs. -0.3, p < 0.0001), disease prevalence (32% vs. 72% significant coronary artery disease [CAD], p < 0.001), and 2-year mortality (1.9% vs. 4.9%, p < 0.0001). The DTS provided information beyond clinical predictors of both coronary disease and survival in women and men. Although overall women had better survival, the DTS performed equally well in stratifying both genders into prognostic categories. The DTS actually performed better in women than in men for excluding disease, with fewer low risk women having any significant coronary disease (> or = 1 vessel with > or =75% stenosis) (20% vs. 47%, p < 0.001), or severe disease (3-vessel disease or > or =75% left main stenosis) (3.5% vs. 11.4%, p < 0.001)., Conclusions: By combining several aspects of treadmill testing, the DTS effectively stratifies women into diagnostic and prognostic risk categories.

Objective: The aim of this study was to examine the effects of provider profiling on bypass surgery access and outcomes in elderly patients in New York., Background: Since 1989, New York (NY) has compiled provider-specific bypass surgery mortality reports. While some have proposed that "provider profiling" has led to lower surgical mortality rates, critics have suggested that such programs lower in-state procedural access (increasing out-of-state transfers) without improving patient outcomes., Methods: Using national Medicare data, we examined trends in the percentages of NY residents aged 65 years or older receiving out-of-state bypass surgery between 1987 and 1992 (before and after program initiation). We also examined in-state procedure use among elderly myocardial infarction patients during this period. Finally, we compared trends in surgical outcomes in NY Medicare patients with those for the rest of the nation., Results: Between 1987 and 1992, the percentage of NY residents receiving bypass out-of-state actually declined (from 12.5% to 11.3%, p < 0.01 for trend). An elderly patient's likelihood for bypass following myocardial infarction in NY increased significantly since the program's initiation. Between 1987 and 1992, unadjusted 30-day mortality rates following bypass declined by 33% in NY Medicare patients compared with a 19% decline nationwide (p < 0.001). As a result of this improvement, NY had the lowest risk-adjusted bypass mortality rate of any state in 1992., Conclusions: We found no evidence that NY's provider profiling limited procedure access in NY's elderly or increased out-of-state transfers. Despite an increasing preoperative risk profile, procedural outcomes in NY improved significantly faster than the national average.

Objectives: This study examined the impact of early hospital discharge on short-term clinical outcomes of elderly patients treated with coronary artery bypass graft surgery (CABG) in the United States in 1992., Background: Protocols that encourage earlier discharge of patients who have had CABG have been implemented across the country. Although delivery of efficient care benefits both patients and providers, premature discharge can adversely affect clinical outcomes, resulting in increased hospital readmissions and higher long-term costs., Methods: We examined the prevalence of early discharge (postoperative length of stay < or = 5 days) among 83,347 non-health maintenance organization (HMO) Medicare patients who underwent CABG in the United States in 1992. Using logistic regression models, we identified patient characteristics associated with early discharge and obtained risk-adjusted rates of death and readmission or death for postoperative lengths of stay between 4 and 14 days., Results: In 1992, 6% of Medicare patients undergoing CABG were discharged within 5 days of the operation. The prevalence of early discharge varied considerably among states, ranging from 1% to 21%. Patients discharged early tended to be younger and male and have fewer comorbid illnesses. Risk-adjusted rates of death and death or cardiovascular readmission were lowest among patients discharged early., Conclusions: As of 1992, early discharge of elderly patients treated with CABG in non-HMO settings was not associated with higher 60-day rates of death or readmission. This suggests that physicians were able to identify low risk candidates for early discharge. Variation across the nation in early discharge rates, along with the percentage of patients without major risk factors for adverse outcomes, suggests that higher rates of early discharge might be safely achieved.

Objectives: The purpose of this consensus effort was to define and prioritize the importance of a set of clinical variables useful for monitoring and improving the short-term mortality of patients undergoing coronary artery bypass graft surgery (CABG)., Background: Despite widespread use of data bases to monitor the outcome of patients undergoing CABG, no consistent set of clinical variables has been defined for risk adjustment of observed outcomes for baseline differences in disease severity among patients., Methods: Experts with a background in epidemiology, biostatistics and clinical care with an interest in assessing outcomes of CABG derived from previous work with professional societies, government or academic institutions volunteered to participate in this unsponsored consensus process. Two meetings of this ad hoc working group were required to define and prioritize clinical variables into core, level 1 or level 2 groupings to reflect their importance for relating to short-term mortality after CABG. Definitions of these 44 variables were simple and specific to enhance objectivity of the 7 core, 13 level 1 and 24 level 2 variables. Core and level 1 variables were evaluated using data from five existing data bases, and core variables only were examined in an additional two data bases to confirm the consensus opinion of the relative prognostic power of each variable., Results: Multivariable logistic regression models of the seven core variables showed all to be predictive of bypass surgery mortality in some of the seven existing data sets. Variables relating to acuteness, age and previous operation proved to be the most important in all data sets tested. Variables describing coronary anatomy appeared to be least significant. Models including both the 7 core and 13 level 1 variables in five of the seven data sets showed the core variables to reflect 45% to 83% of the predictive information. However, some level 1 variables were stronger than some core variables in some data sets., Conclusions: A relatively small number of clinical variables provide a large amount of prognostic information in patients undergoing CABG.