Richard A Boss

Recent Changes in Practice of Elective Percutaneous Coronary Intervention for Stable Angina

Background— The COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial was designed to compare optimal medical therapy alone versus optimal medical therapy and percutaneous coronary intervention (PCI) for treatment of patients with stable coronary artery disease and showed equal efficacy for optimal medical therapy with or without PCI. The impact of results from the COURAGE trial on clinical practice is unknown. Methods and Results— We analyzed 26 388 consecutive patients from the Northern New England Cardiovascular Disease PCI Registry who underwent PCI between January 2006 and June 2009. We identified a COURAGE-like patient group as patients who were undergoing (1) an elective procedure; (2) for an indication of stable angina; and (3) on the day of admission (ie, the date of admission was the same as the procedure date). All other PCI patients were placed in an “other indications” cohort. We compared temporal trends in overall volume in PCI for stable angina and for other indications, comparing quarterly time periods before and after release of COURAGE in March 2007. Over the study period, there was a statistically significant decrease in total PCI volume from 2064 in Quarter 1 2006 (before COURAGE) to 1708 in Quarter 3 2007 (after COURAGE) (P<0.01). These trends were sustained through June 2009, with an approximate 16% peak relative reduction in all PCI compared with before COURAGE. As a percentage of all PCI, stable angina reached a high of 20.9% before COURAGE and began to decrease immediately after publication of COURAGE in Quarter 2 2007 to 16.1% (P<0.01). Among patients undergoing PCI for stable angina, there was a significant 26% peak decrease in post-COURAGE PCI volumes compared with pre-COURAGE Quarter 1 2006 (P trend, 0.01), which was maintained through the end of the study period. Conclusions— Publication of results from the COURAGE trial was temporally associated with a significant and sustained decline in the use of PCI to treat patients with stable angina. The long-term impact of this change in practice on patient outcomes remains to be determined.

Outcomes of Patients Undergoing Concomitant Aortic and Mitral Valve Surgery in Northern New England

Background— Concomitant aortic (AV) and mitral (MV) valve surgery accounts for 4% of all valve procedures in northern New England. We examined in-hospital and long-term mortality. Methods and Results— This is a report of a prospective study of 1057 patients undergoing concomitant AV and MV surgery from 1989 to 2007. The Social Security Administration Death Master File was used to assess long-term survival. Kaplan–Meier and log-rank tests were performed. In-hospital mortality was 15.5% (11.0% for patients <70 years, 18.0% for 70- to 79-year-olds, and 24% for those ≥80 years). Overall median survival was 7.3 years. Median survival without coronary artery bypass grafting was 9.5 years and with coronary artery bypass grafting was 5.7 years (P<0.001). Survival in women was worse than in men (7.3 versus 9.3, years, P=0.033). Median survival by age was 11.0 years for patients <70 years, 5.4 years for 70- to 79-year-olds, and 4.8 years for those ≥80 years. Median survival was not significantly different for patients ≥80 years compared with those who were 70 to 79 years old (P=0.245). Conclusions— Double-valve surgery has a high in-hospital mortality rate and a median survival of 7.3 years. After patients have survived surgery, long-term survival is similar between men and women, smaller and larger patients, and those receiving MV repair or replacement. Survival continues to decline after surviving surgery for patients ≥70 years old and those who undergo concomitant coronary artery bypass grafting. In patients <70 years, either mechanical valves in both positions or a tissue AV and mitral repair have the lowest in-hospital mortality and the best long-term survival. In patients ≥70 years, tissue valves in both positions have the best in-hospital and long-term survival.

Impact of perioperative acute kidney injury as a severity index for thirty-day readmission after cardiac surgery.

BACKGROUND Of patients undergoing cardiac surgery in the United States, 15% to 20% are re-hospitalized within 30 days. Current models to predict readmission have not evaluated the association between severity of postoperative acute kidney injury (AKI) and 30-day readmissions. METHODS We collected data from 2,209 consecutive patients who underwent either coronary artery bypass or valve surgery at 7 member hospitals of the Northern New England Cardiovascular Disease Study Group Cardiac Surgery Registry between July 2008 and December 2010. Administrative data at each hospital were searched to identify all patients readmitted to the index hospital within 30 days of discharge. We defined AKI stages by the AKI Network definition of 0.3 or 50% increase (stage 1), twofold increase (stage 2), and a threefold or 0.5 increase if the baseline serum creatinine was at least 4.0 (mg/dL) or new dialysis (stage 3). We evaluate the association between stages of AKI and 30-day readmission using multivariate logistic regression. RESULTS There were 260 patients readmitted within 30 days (12.1%). The median time to readmission was 9 (interquartile range, 4 to 16) days. Patients not developing AKI after cardiac surgery had a 30-day readmission rate of 9.3% compared with patients developing AKI stage 1 (16.1%), AKI stage 2 (21.8%), and AKI stage 3 (28.6%, p < 0.001). Adjusted odds ratios for AKI stage 1 (1.81; 1.35, 2.44), stage 2 (2.39; 1.38, 4.14), and stage 3 (3.47; 1.85 to 6.50). Models to predict readmission were significantly improved with the addition of AKI stage (c-statistic 0.65, p = 0.001) and net reclassification rate of 14.6% (95% confidence interval: 5.05% to 24.14%, p = 0.003). CONCLUSIONS In addition to more traditional patient characteristics, the severity of postoperative AKI should be used when assessing a patients risk for readmission.

How do centres begin the process to prevent contrast-induced acute kidney injury: a report from a new regional collaborative

Objectives This study evaluates the variation in practice patterns associated with contrast-induced acute kidney injury (CI-AKI) and identifies clinical practices that have been associated with a reduction in CI-AKI. Background CI-AKI is recognised as a complication of invasive cardiovascular procedures and is associated with cardiovascular events, prolonged hospitalisation, end-stage renal disease, and all-cause mortality. Reducing the risk of CI-AKI is a patient safety objective set by the National Quality Forum. Methods This study prospectively collected quantitative and qualitative data from 10 centres, which participate in the Northern New England Cardiovascular Disease Study Group PCI Registry. Quantitative data were collected from the PCI Registry. Qualitative data were obtained through clinical team meetings to map care processes related to CI-AKI and focus groups to understand attitudes towards CI-AKI prophylaxis. Fixed and random effects modelling were conducted to test the differences across centres. Results Significant variation in rates of CI-AKI were found across 10 medical centres. Both fixed effects and mixed effects logistic regression demonstrated significant variability across centres, even after adjustment for baseline covariates (p<0.001 for both modelling approaches). Patterns were found in reported processes and clinical leadership that were attributable to centres with lower rates of CI-AKI. These included reducing nil by mouth (NPO) time to 4 h prior to case, and standardising volume administration protocols in combination with administering three to four high doses of N-acetylcysteine (1200 mg) for each patient. Conclusions These data suggest that clinical leadership and institution-focused efforts to standardise preventive practices can help reduce the incidence of CI-AKI.

Reducing Contrast-Induced Acute Kidney Injury Using a Regional Multicenter Quality Improvement Intervention

Background—Contrast-induced acute kidney injury (CI-AKI) is associated with increased morbidity and mortality after percutaneous coronary interventions and is a patient safety objective of the National Quality Forum. However, no formal quality improvement program to prevent CI-AKI has been conducted. Therefore, we sought to determine whether a 6-year regional multicenter quality improvement intervention could reduce CI-AKI after percutaneous coronary interventions. Methods and Results—We conducted a prospective multicenter quality improvement study to prevent CI-AKI (serum creatinine increase ≥0.3 mg/dL within 48 hours or ≥50% during hospitalization) among 21 067 nonemergent patients undergoing percutaneous coronary interventions at 10 hospitals between 2007 and 2012. Six intervention hospitals participated in the quality improvement intervention. Two hospitals with significantly lower baseline rates of CI-AKI, which served as benchmark sites and were used to develop the intervention, and 2 hospitals not receiving the intervention were used as controls. Using time series analysis and multilevel poisson regression clustering to the hospital level, we calculated adjusted risk ratios for CI-AKI comparing the intervention period to baseline. Adjusted rates of CI-AKI were significantly reduced in hospitals receiving the intervention by 21% (risk ratio, 0.79; 95% confidence interval: 0.67–0.93; P=0.005) for all patients and by 28% in patients with baseline estimated glomerular filtration rate <60 mL/min per 1.73 m2 (risk ratio, 0.72; 95% confidence interval: 0.56–0.91; P=0.007). Benchmark hospitals had no significant changes in CI-AKI. Key qualitative system factors associated with improvement included multidisciplinary teams, limiting contrast volume, standardized fluid orders, intravenous fluid bolus, and patient education about oral hydration. Conclusions—Simple cost-effective quality improvement interventions can prevent ⩽1 in 5 CI-AKI events in patients with undergoing nonemergent percutaneous coronary interventions.

Preoperative White Blood Cell Count and Risk of 30-Day Readmission after Cardiac Surgery

Approximately 1 in 5 patients undergoing cardiac surgery are readmitted within 30 days of discharge. Among the primary causes of readmission are infection and disease states susceptible to the inflammatory cascade, such as diabetes, chronic obstructive pulmonary disease, and gastrointestinal complications. Currently, it is not known if a patients baseline inflammatory state measured by crude white blood cell (WBC) counts could predict 30-day readmission. We collected data from 2,176 consecutive patients who underwent cardiac surgery at seven hospitals. Patient readmission data was abstracted from each hospital. The independent association with preoperative WBC count was determined using logistic regression. There were 259 patients readmitted within 30 days, with a median time of readmission of 9 days (IQR 4–16). Patients with elevated WBC count at baseline (10,000–12,000 and >12,000 mm3) had higher 30-day readmission than those with lower levels of WBC count prior to surgery (15% and 18% compared to 10%–12%, P = 0.037). Adjusted odds ratios were 1.42 (0.86, 2.34) for WBC counts 10,000–12,000 and 1.81 (1.03, 3.17) for WBC count > 12,000. We conclude that WBC count measured prior to cardiac surgery as a measure of the patients inflammatory state could aid clinicians and continuity of care management teams in identifying patients at heightened risk of 30-day readmission after discharge from cardiac surgery.

IS THE USE OF DRUG-ELUTING STENTS RELATED TO THE RISK OF TARGET VESSEL REVASCULARIZATION

The benefit of drug-eluding stents (DES) in reducing target vessel revascularization (TVR) is greatest in patients at high risk of restenosis with bare metal stents (BMS). Lowering the risk of TVR with DES must be weighed against the potential increased risks of stent thrombosis and of bleeding from