Frederick L. Grover

Annual Outcomes With Transcatheter Valve Therapy: From the STS/ACC TVT Registry.

BACKGROUND The Society of Thoracic Surgeons (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) Registry has been a joint initiative of the STS and the ACC in concert with multiple stakeholders. The TVT Registry has important information regarding patient selection, delivery of care, science, education, and research in the field of structural valvular heart disease. OBJECTIVES This report provides an overview on current U.S. TVT practice and trends. The emphasis is on demographics, in-hospital procedural characteristics, and outcomes of patients having transcatheter aortic valve replacement (TAVR) performed at 348 U.S. centers. METHODS The TVT Registry captured 26,414 TAVR procedures as of December 31, 2014. Temporal trends between 2012 and 2013 versus 2014 were compared. RESULTS Comparison of the 2 time periods reveals that TAVR patients remain elderly (mean age 82 years), with multiple comorbidities, reflected by a high mean STS predicted risk of mortality (STS PROM) for surgical valve replacement (8.34%), were highly symptomatic (New York Heart Association functional class III/IV in 82.5%), frail (slow 5-m walk test in 81.6%), and have poor self-reported health status (median baseline Kansas City Cardiomyopathy Questionnaire score of 39.1). Procedure performance is changing, with an increased use of moderate sedation (from 1.6% to 5.1%) and increase in femoral access using percutaneous techniques (66.8% in 2014). Vascular complication rates are decreasing (from 5.6% to 4.2%), whereas site-reported stroke rates remain stable at 2.2%. CONCLUSIONS The TVT Registry provides important information on characteristics and outcomes of TAVR in contemporary U.S. clinical practice. It can be used to identify trends in practice and opportunities for quality improvement.

Mortality after cardiac bypass surgery: prediction from administrative versus clinical data.

Background:Risk-adjusted outcome rates frequently are used to make inferences about hospital quality of care. We calculated risk-adjusted mortality rates in veterans undergoing isolated coronary artery bypass surgery (CABS) from administrative data and from chart-based clinical data and compared the assessment of hospital high and low outlier status for mortality that results from these 2 data sources. Study Population:We studied veterans who underwent CABS in 43 VA hospitals between October 1, 1993, and March 30, 1996 (n = 15,288). Methods:To evaluate administrative data, we entered 6 groups of International Classification of Diseases (ICD)-9-CM codes for comorbid diagnoses from the VA Patient Treatment File (PTF) into a logistic regression model predicting postoperative mortality. We also evaluated counts of comorbid ICD-9-CM codes within each group, along with 3 common principal diagnoses, weekend admission or surgery, major procedures associated with CABS, and demographic variables. Data from the VA Continuous Improvement in Cardiac Surgery Program (CICSP) were used to create a separate clinical model predicting postoperative mortality. For each hospital, an observed-to-expected (O/E) ratio of mortality was calculated from (1) the PTF model and (2) the CICSP model. We defined outlier status as an O/E ratio outside of 1.0 (based on the hospitals 90% confidence interval). To improve the statistical and predictive power of the PTF model, selected clinical variables from CICSP were added to it and outlier status reassessed. Results:Significant predictors of postoperative mortality in the PTF model included 1 group of comorbid ICD-9-CM codes, intraortic balloon pump insertion before CABS, angioplasty on the day of or before CABS, weekend surgery, and a principal diagnosis of other forms of ischemic heart disease. The models c-index was 0.698. As expected, the CICSP models predictive power was significantly greater than that of the administrative model (c = 0.761). The addition of just 2 CICSP variables to the PTF model improved its predictive power (c = 0.741). This model identified 5 of 6 high mortality outliers identified by the CICSP model. Additional CICSP variables were statistically significant predictors but did not improve the assessment of high outlier status. Conclusions:Models using administrative data to predict postoperative mortality can be improved with the addition of a very small number of clinical variables. Limited clinical improvements of administrative data may make it suitable for use in quality improvement efforts.

Effect of definition of mortality on Hospital profiles

Background: Hospitals are ranked based on risk-adjusted measures of postoperative mortality, but definitions differ about which deaths following surgery should be included. Objective: To determine whether varying the case definition of deaths following surgery that are included in coronary artery bypass surgery quality assessment affects the identification of outlier hospitals. Research Design: The study used a prospective cohort design. Subjects: A total of 15,288 patients undergoing coronary artery bypass surgery without other cardiac procedures from October 1993 to March 1996 at all (N = 43) Veterans Affairs hospitals that conduct cardiac surgery. Measures: The first measure included any death occurring within 30 days after surgery, regardless of cause, in or out of the hospital (30-day mortality). The second measure included 30-day mortality plus any death occurring 30 days to 6 months after surgery that was judged to be a direct result of a perioperative complication of the surgery (all procedure-related mortality). Results: Hospital performance as assessed by the two different definitions of death varied substantially. The rankings of hospitals differed for 86% (37/43) of hospitals. Twenty-one percent (9/43) changed their quartile of rank, and five hospitals changed their outlier status. The correlation of observed-to-expected ratios was high (r = 0.96), but there was disagreement of outlier status (&kgr; = 0.71). Conclusions: Judgments regarding the quality of a hospital’s performance of coronary artery bypass surgery vary depending on the definition of postoperative mortality that is used. Further research is needed to assess what definition is most appropriate to identify quality of care problems.

The importance of patient-specific preoperative factors: an analysis of the society of thoracic surgeons congenital heart surgery database.

BACKGROUND The most common forms of risk adjustment for pediatric and congenital heart surgery used today are based mainly on the estimated risk of mortality of the primary procedure of the operation. The goals of this analysis were to assess the association of patient-specific preoperative factors with mortality and to determine which of these preoperative factors to include in future pediatric and congenital cardiac surgical risk models. METHODS All index cardiac operations in The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS-CHSD) during 2010 through 2012 were eligible for inclusion. Patients weighing less than 2.5 kg undergoing patent ductus arteriosus closure were excluded. Centers with more than 10% missing data and patients with missing data for discharge mortality or other key variables were excluded. Rates of discharge mortality for patients with or without specific preoperative factors were assessed across age groups and were compared using Fishers exact test. RESULTS In all, 25,476 operations were included (overall discharge mortality 3.7%, n=943). The prevalence of common preoperative factors and their associations with discharge mortality were determined. Associations of the following preoperative factors with discharge mortality were all highly significant (p<0.0001) for neonates, infants, and children: mechanical circulatory support, renal dysfunction, shock, and mechanical ventilation. CONCLUSIONS Current STS-CHSD risk adjustment is based on estimated risk of mortality of the primary procedure of the operation as well as age, weight, and prematurity. The inclusion of additional patient-specific preoperative factors in risk models for pediatric and congenital cardiac surgery could lead to increased precision in predicting risk of operative mortality and comparison of observed to expected outcomes.

Effect of a Nonionic Surface-Active Agent on Blood Viscosity and Platelet Adhesiveness

The effects of Pluronic F68, a nonionic surface-active agent, on blood viscosity and platelet adhesiveness during extracorporeal circulation were investigated. Blood viscosity was significantly decreased. Platelet adhesiveness decreased markedly in six patients within ten minutes after intravenous injection. Pluronic F68 has many properties and actions which make it a useful additive to perfusion systems. Its potential in the treatment of diseases in which high viscosity or increased platelet adhesiveness are present deserves investigation.