Fred H. Edwards

ACC/AHA 2004 guideline update for coronary artery bypass graft surgery: summary article. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1999 Guidelines for Coronary Artery Bypass Graft Surgery).

The American College of Cardiology (ACC)/American Heart Association (AHA) Task Force on Practice Guidelines regularly reviews existing guidelines to determine when an update or full revision is needed. This process gives priority to areas where major changes in text, particularly recommendations, are mentioned on the basis of new understanding of evidence. Minor changes in verbiage and references are discouraged. The ACC/AHA Guidelines for Coronary Artery Bypass Graft Surgery published in 1999 have now been updated. The full-text guidelines incorporating the updated material are available on the Internet (www.acc.org or www.americanheart.org) in both a version that shows the changes from the 1999 guidelines in track changes mode, with strike-through indicating deleted text and underlining indicating new text, and a “clean” version that fully incorporates the changes. This article describes the major areas of change reflected in the update in a format that we hope can be read and understood as a stand-alone document. Please note we have changed the table of contents headings in the 1999 guidelines from roman numerals to unique identifying numbers. Interested readers are referred to the full-length Internet version to completely understand the context of these changes. Classification of Recommendations and Level of Evidence are expressed in the ACC/AHA format as follows: ### Classification of Recommendations ### Level of Evidence

The Society of Thoracic Surgeons 2008 cardiac surgery risk models: part 1--coronary artery bypass grafting surgery.

BACKGROUND The first version of The Society of Thoracic Surgeons National Adult Cardiac Surgery Database (STS NCD) was developed nearly 2 decades ago. Since its inception, the number of participants has grown dramatically, patient acuity has increased, and overall outcomes have consistently improved. To adjust for these and other changes, all STS risk models have undergone periodic revisions. This report provides a detailed description of the 2008 STS risk model for coronary artery bypass grafting surgery (CABG). METHODS The study population consisted of 774,881 isolated CABG procedures performed on adult patients aged 20 to 100 years between January 1, 2002, and December 31, 2006, at 819 STS NCD participating centers. This cohort was randomly divided into a 60% training (development) sample and a 40% test (validation) sample. The development sample was used to identify predictor variables and estimate model coefficients. The validation sample was used to assess model calibration and discrimination. Model outcomes included operative mortality, renal failure, stroke, reoperation for any cause, prolonged ventilation, deep sternal wound infection, composite major morbidity or mortality, prolonged length of stay (> 14 days), and short length of stay (< 6 days and alive). Candidate predictor variables were selected based on their availability in versions 2.35, 2.41, and 2.52.1 of the STS NCD and their presence in (or ability to be mapped to) version 2.61. Potential predictor variables were screened for overall prevalence in the study population, missing data frequency, coding concerns, bivariate relationships with outcomes, and their presence in previous STS or other CABG risk models. Supervised backwards selection was then performed with input from an expert panel of cardiac surgeons and biostatisticians. After successfully validating the fit of the models, the development and validation samples were subsequently combined, and the final regression coefficients were estimated using the overall combined (development plus validation) sample. RESULTS The c-index for the mortality model was 0.812, and the c-indices for other endpoints ranged from 0.653 for reoperation to 0.793 for renal failure in the validation sample. Plots of observed versus predicted event rates revealed acceptable calibration in the overall population and in numerous subgroups. When patients were grouped into categories of predicted risk, the absolute difference between the observed and expected event rates was less than 1.5% for each endpoint. The final model intercept and coefficients are provided. CONCLUSIONS New STS risk models have been developed for CABG mortality and eight other endpoints. Detailed descriptions of model development and testing are provided, together with the final algorithm. Overall model performance is excellent.

The Society of Thoracic Surgeons 2008 cardiac surgery risk models: part 2--isolated valve surgery.

BACKGROUND Adjustment for case-mix is essential when using observational data to compare surgical techniques or providers. That is most often accomplished through the use of risk models that account for preoperative patient factors that may impact outcomes. The Society of Thoracic Surgeons (STS) uses such risk models to create risk-adjusted performance reports for participants in the STS National Adult Cardiac Surgery Database (NCD). Although risk models were initially developed for coronary artery bypass surgery, similar models have now been developed for use with heart valve surgery, particularly as the proportion of such procedures has increased. The last published STS model for isolated valve surgery was based on data from 1994 to 1997 and did not include patients undergoing mitral valve repair. STS has developed new valve surgery models using contemporary data that include both valve repair as well as replacement. Expanding upon existing valve models, the new STS models include several nonfatal complications in addition to mortality. METHODS Using STS data from 2002 to 2006, isolated valve surgery risk models were developed for operative mortality, permanent stroke, renal failure, prolonged ventilation (> 24 hours), deep sternal wound infection, reoperation for any reason, a major morbidity or mortality composite endpoint, prolonged postoperative length of stay, and short postoperative length of stay. The study population consisted of adult patients who underwent one of three types of valve surgery: isolated aortic valve replacement (n = 67,292), isolated mitral valve replacement (n = 21,229), or isolated mitral valve repair (n = 21,238). The population was divided into a 60% development sample and a 40% validation sample. After an initial empirical investigation, the three surgery groups were combined into a single logistic regression model with numerous interactions to allow the covariate effects to differ across these groups. Variables were selected based on a combination of automated stepwise selection and expert panel review. RESULTS Unadjusted operative mortality (in-hospital regardless of timing, and 30-day regardless of venue) for all isolated valve procedures was 3.4%, and unadjusted in-hospital morbidity rates ranged from 0.3% for deep sternal wound infection to 11.8% for prolonged ventilation. The number of predictors in each model ranged from 10 covariates in the sternal infection model to 24 covariates in the composite mortality plus morbidity model. Discrimination as measured by the c-index ranged from 0.639 for reoperation to 0.799 for mortality. When patients in the validation sample were grouped into 10 categories based on deciles of predicted risk, the average absolute difference between observed versus predicted events within these groups ranged from 0.06% for deep sternal wound infection to 1.06% for prolonged postoperative stay. CONCLUSIONS The new STS risk models for valve surgery include mitral valve repair as well as multiple endpoints other than mortality. Model coefficients are provided and an online risk calculator is publicly available from The Society of Thoracic Surgeons website.

The society of thoracic surgeons: 30-day operative mortality and morbidity risk models

BACKGROUND Although 30 day risk-adjusted operative mortality (ROM) has been used for quality assessment, it is not sufficient to describe the outcomes after coronary artery bypass grafting (CABG) surgery. Risk-adjusted major morbidity may differentially impact quality of care (as complications occur more frequently than death) and enhance a surgical teams ability to assess their quality. This study identified the preoperative risk factors associated with several complications and a composite outcome (the presence of any major morbidity or 30-day operative mortality or both). METHODS For CABG procedures, the 1997 to 1999 Society of Thoracic Surgeons (STS) National Adult Cardiac Surgery Database was used to develop ROM and risk-adjusted morbidity (ROMB) models. Risk factors were selected using standard STS univariate screening and multivariate logistic regression approaches. Risk model performance was assessed. Across STS participating sites, the association of observed-to-expected (O/E) ratios for ROM and ROMB was evaluated. RESULTS The 30-day operative death and major complication rates for STS CABG procedures were 3.05% and 13.40%, respectively (503,478 CABG procedures), including stroke (1.63%), renal failure (3.53%), reoperation (5.17%), prolonged ventilation (5.96%), and sternal infection (0.63%). Risk models were developed (c-indexes for stroke [0.72], renal failure [0.76], reoperation [0.64], prolonged ventilation [0.75], sternal infection [0.66], and the composite endpoint [0.71]). Only a slight correlation was found, however, between ROMB and ROM indicators. CONCLUSIONS Used in combination, ROMB and ROM may provide the surgical team with additional information to evaluate the quality of their care as well as valuable insights to allow them to focus on areas for improvement.

2012 ACCF/AATS/SCAI/STS expert consensus document on transcatheter aortic valve replacement.

Robert A. Harrington, MD, FACC, Chair Deepak L. Bhatt, MD, MPH, FACC, Vice Chair Victor A. Ferrari, MD, FACC John D. Fisher, MD, FACC Mario J. Garcia, MD, FACC Timothy J. Gardner, MD, FACC Federico Gentile, MD, FACC Michael F. Gilson, MD, FACC Adrian F. Hernandez, MD, FACC Alice K. Jacobs

Comparative Effectiveness of Revascularization Strategies

BACKGROUND Questions persist concerning the comparative effectiveness of percutaneous coronary intervention (PCI) and coronary-artery bypass grafting (CABG). The American College of Cardiology Foundation (ACCF) and the Society of Thoracic Surgeons (STS) collaborated to compare the rates of long-term survival after PCI and CABG. METHODS We linked the ACCF National Cardiovascular Data Registry and the STS Adult Cardiac Surgery Database to claims data from the Centers for Medicare and Medicaid Services for the years 2004 through 2008. Outcomes were compared with the use of propensity scores and inverse-probability-weighting adjustment to reduce treatment-selection bias. RESULTS Among patients 65 years of age or older who had two-vessel or three-vessel coronary artery disease without acute myocardial infarction, 86,244 underwent CABG and 103,549 underwent PCI. The median follow-up period was 2.67 years. At 1 year, there was no significant difference in adjusted mortality between the groups (6.24% in the CABG group as compared with 6.55% in the PCI group; risk ratio, 0.95; 95% confidence interval [CI], 0.90 to 1.00). At 4 years, there was lower mortality with CABG than with PCI (16.4% vs. 20.8%; risk ratio, 0.79; 95% CI, 0.76 to 0.82). Similar results were noted in multiple subgroups and with the use of several different analytic methods. Residual confounding was assessed by means of a sensitivity analysis. CONCLUSIONS In this observational study, we found that, among older patients with multivessel coronary disease that did not require emergency treatment, there was a long-term survival advantage among patients who underwent CABG as compared with patients who underwent PCI. (Funded by the National Heart, Lung, and Blood Institute.).

Coronary artery bypass grafting: The Society of Thoracic Surgeons National Database experience

The need for accurate risk assessment has become an indispensable element in the practice of cardiac surgery. The Society of Thoracic Surgeons National Cardiac Surgery Database allows subscribing institutions to perform sophisticated patient risk assessment using traditional statistical tools and a newly developed risk model of operative mortality. The database experience with isolated coronary artery bypass grafting has been studied most closely at this point and serves as the basis for this report. The approach to operative risk assessment is presented along with an analysis of important risk factors in the practice of coronary artery surgery from 1980 through 1990. The database contains records of 80,881 patients undergoing coronary artery bypass grafting in numerous institutions from 1980 through 1990. These records were used to conduct a detailed analysis of risk factors associated with coronary operations in this time interval and to present statistical methods used to formulate a risk equation that allows one to predict the probability of operative death. In the course of this decade, there were clearly defined trends showing a statistically significant increase in adverse patient risk factors. The risk model has proven to be a reliable tool for predicting the probability of operative death in an individual patient and may be valuable in both patient counseling and medical decision making. Large multi-institutional databases of this type are key ingredients of modern operative risk assessment. A database containing a broad national experience of this type can represent an aggregate experience that may well approximate a universally accepted standard of care.

Impact of gender on coronary bypass operative mortality

BACKGROUND In spite of many reports investigating the influence of gender on coronary artery operations, it is still uncertain whether gender is an independent risk factor for operative mortality. A major problem of previous reports has centered around the fact that men and women constitute quite different populations, thereby making direct comparisons difficult. METHODS The Society of Thoracic Surgeons National Cardiac Surgery Database was used to retrospectively examine 344,913 patients undergoing coronary artery bypass graft operations from 1994 through the most recent data harvest. The operative mortality of male and female patients was compared for a variety of single risk factors and combinations of risk factors. A logistic risk model was used to account for all important patient parameters so that individuals could be stratified into comparable categories allowing for direct comparisons of risk-matched male and female patients. RESULTS The univariate analysis showed that the 97,153 women carried a significantly higher mortality for each of the risk factors examined. The multivariate analysis and the risk model stratification showed that women had significantly higher mortality as compared to equally matched men in the low- and medium-risk part of the spectrum, but in high-risk patients, there was no difference between male and female mortality. CONCLUSIONS Gender is an independent predictor of operative mortality except for patients in very high-risk categories.

Prediction of operative mortality after valve replacement surgery

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.

Outcomes Following Transcatheter Aortic Valve Replacement in the United States

IMPORTANCE Transcatheter aortic valve replacement (TAVR) was approved by the US Food and Drug Administration for the treatment of severe, symptomatic aortic stenosis and inoperable status (in 2011) and high-risk but operable status (starting in 2012). A national registry (the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy [STS/ACC TVT] Registry) was initiated to meet a condition for Medicare coverage and also facilitates outcome assessment and comparison with other trials and international registries. OBJECTIVE To report the initial US commercial experience with TAVR. DESIGN, SETTING, AND PARTICIPANTS We obtained results from all eligible US TAVR cases (n=7710) from 224 participating registry hospitals following the Edwards Sapien XT device commercialization (November 2011-May 2013). MAIN OUTCOMES AND MEASURES Primary outcomes included all-cause in-hospital mortality and stroke following TAVR. Secondary analyses included procedural complications and outcomes by clinical indication and access site. Device implantation success was defined as successful vascular access, deployment of a single device in the proper anatomic position, appropriate valve function without either moderate or severe AR, and successful retrieval of the delivery system. Thirty-day outcomes are presented for a representative 3133 cases (40.6%) at 114 centers with at least 80% complete follow-up reporting. RESULTS The 7710 patients who underwent TAVR included 1559 (20%) cases that were inoperable and 6151 (80%) cases that were high-risk but operable. The median age was 84 years (interquartile range [IQR], 78-88 years); 3783 patients (49%) were women and the median STS predicted risk of mortality was 7% (IQR, 5%-11%). At baseline, 2176 patients (75%) were either not at all satisfied (1297 patients [45%]) or mostly dissatisfied (879 patients [30%]) with their symptom status; 2198 (72%) had a 5-m walk time longer than 6 seconds (slow gait speed). The most common vascular access approach was transfemoral (4972 patients [64%]), followed by transapical (2197 patients [29%]) and other alternative approaches (536 patients [7%]); successful device implantation occurred in 7069 patients (92%; 95% CI, 91%-92%). The observed incidence of in-hospital mortality was 5.5% (95% CI, 5.0%-6.1%). Other major complications included stroke (2.0%; 95% CI, 1.7%-2.4%), dialysis-dependent renal failure (1.9%; 95% CI, 1.6%-2.2%), and major vascular injury (6.4%; 95% CI, 5.8%-6.9%). Median hospital stay was 6 days (IQR, 4-10 days), with 4613 (63%) discharged home. Among patients with available follow-up at 30 days (n=3133), the incidence of mortality was 7.6% (95% CI, 6.7%-8.6%) (noncardiovascular cause, 52%); a stroke had occurred in 2.8% (95% CI, 2.3%-3.5%), new dialysis in 2.5% (95% CI, 2.0%-3.1%), and reintervention in 0.5% (95% CI, 0.3%-0.8%). CONCLUSIONS AND RELEVANCE Among patients undergoing TAVR at US centers in the STS/ACC TVT Registry, device implantation success was achieved in 92% of cases, the overall in-hospital mortality rate was 5.5%, and the stroke rate was 2.0%. Although these postmarket US approval findings are comparable with prior published trial data and international experience, long-term follow-up is essential to assess continued efficacy and safety. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01737528.