A significant number of our older Veterans are affected by cardiovascular diseases such as congestive heart failure, coronary artery disease, and comorbid conditions such as high blood pressure and diabetes. Ischemic heart disease alone is one of the most prevalent health problems among Veterans, resulting in over 25,000 admissions to VA hospitals annually. Addressing the impact of coronary disease and its care among Veterans is of critical importance to VHA.

Emerging Evidence presents four recently completed studies that address several aspects of coronary care.

Keywords: heart disease, diabetes, coronary, ischemia, myocardial infarction, heart attack, hypertension, heart failure, CAD, CHF

1. When Administered Appropriately, Beta-Blockers Can Improve Outcomes in Heart Failure

Completed in March 2008, this study sought to understand outcomes related to differing dosages of two common beta-blockers used to treat heart failure. (Study no.: IIR 05-243. PI: Thomas S. Rector, PharmD, PhD)

Questions

What is the utilization in Veterans with heart failure who are prescribed one of two commonly used beta-blockers (carvedilol or controlled-release metoprolol)?

Results

• After a median time on therapy of over 1 year, the majority of prescribed daily doses of both medications were much lower than the recommended effective dosage.
• Older age was independently associated with lower prescribed daily dose, as was a history of pulmonary disease.
• Comorbidity, such as pulmonary disease, was associated with prescribing a lower dose of prescribed medication.

Implications

Beta-blockers can improve outcomes in Veterans with heart failure, and the findings suggest that quality improvement efforts should focus on more closely aligning the prescription of beta-blockers with established clinical guidelines.

2. Consistency in Surgical Blood Transfusion Practices Improves Cardiovascular Outcomes

Researchers at the VA Medical Center in Providence, RI concluded this study about variability in surgical blood transfusion practices and cardiovascular outcomes in January 2007. (Study no.: IIR 04-313. PI: Wen-Chih H. Wu, MD.)

Questions

Is there an association between anemia prior to surgery, surgical blood transfusion status, and the risk for heart attack or stroke within 30 days after surgery? Further, is there a relationship between a VA hospital's rates of heart attack and stroke within 30 days of surgery, and that hospital's variability in the adherence to American Society of Anesthesiologists (ASA) blood transfusion guidelines?

Results

• For every percent increase or decrease in red blood cell count from normal range, there was a 1.6% increase in mortality within 30 days after surgery.
• The adjusted risk for death or a cardiac event within 30 days after surgery began to rise when red blood cell counts exceeded 51% of normal range.
• The adjusted risk for death or a cardiac event was greatest when red blood cell counts were between 18% to 29.9% of normal range
• Blood transfusion during surgery was associated with: (a) a decreased risk for death in patients whose red blood cell counts were 24% to 30% of normal range prior to surgery, and (b) an increased risk for death in patients whose red blood cell counts were greater than 30% prior to surgery.
• Large inter-hospital variability in surgical transfusion processes exists, and variability is dependent on red blood cell counts.

Implications

The authors suggest that there is an optimal red blood cell value for patients undergoing major, non-cardiac surgery, and that adhering closely to that value can decrease mortality and cardiac events for those patients. The authors also found that quality improvement efforts should focus on consistency regarding hospitals' approaches to existing ASA clinical guidelines for surgical transfusion.

3. Identifying Evidence-Based Practices in Cardiac Care

In this study, completed in February 2008, investigators created a database of patients with a diagnosis of acute myocardial infarction (AMI) or unstable angina (UA) in order to identify gaps in performance. (Study no.:MRC 03-334. PI: Stephan D. Fihn, MD, MPH.)

Questions

By following all patients discharged from VHA after a diagnosis of AMI or UA, will investigators be able to effectively identify gaps in performance that may be improved by implementation of evidence-based best practices?

Results

• From 2004 to 2006, investigators observed a relative decrease of 15% in 30-day mortality following AMI in VHA.
• Between FY04 and FY06, the number of patients receiving electrocardiogram (ECG) within 10 minutes of a cardiac event increased from 51.1% to 61.6%.
• Between FY04 and FY06, the percent of patients with a troponin report within 60 minutes of a cardiac event—an important indicator of cardiac damage—increased by 5%.

Implications

The authors suggest that based on findings gathered from extensive clinical follow-up data, they were able to clearly show a significant decrease in cardiac mortality following AMI among patients admitted to VHA medical centers. Further, the authors have identified that VHA patients are receiving improved quality of care surrounding AMI, as evidenced by the increase in immediate post-AMI interventions (ECG, troponin report) that adhere to best-practice guidelines.

4. Chronic Heart Failure Benefits from Nurse Case Management

In this study, completed in December 2006, investigators sought to understand whether nurse-directed case management can improve outcomes for patients with chronic heart failure. (Study no.: CHI 99-236. PI: Julie Lowery, PhD.)

Questions

Can outcomes for patients with chronic heart failure (CHF) be improved by nurse-directed case management at a range of tertiary and primary care VA medical centers?

Results

• The control group (usual care) had significantly more CHF and all-cause admissions after one year than the intervention (nurse case management) group.
• Patients in the control group were 2.4 times more likely to die in year 1 than the intervention group, and 1.9 times more likely to die in year two.
• There was a significant difference in all-cause mortality between the two cohorts at both one and two years.
• There were no differences in admissions between the control and the intervention groups at two years.
• Patient satisfaction with cardiology care was consistently higher in the intervention group.

Implications

The investigators believe that the intervention had the intended effect of reducing admissions, bed days of care, and mortality. The authors attribute the lack of difference in admission between the two groups at year 2 to the nature of CHF, which has an inevitable progression, and therefore, many of the patients in the intervention cohort may have begun to experience the increasingly difficult effects of the disease. The authors further suggest that the overall results were consistent with prior studies of nurse case management among select CHF patients in tertiary care facilities, and also suggest that the decline in overall mortality for the intervention group may be attributable to the impact that close nurse case management had on patients' existing disease and comorbidities.