Proven Acute MI Therapies Underused in 50% of Patients
Proven Acute MI Therapies Underused in 50% of Patients
By Barbara Biedrzycki, RN, MSN, AOCN, CRNP
Summary—Studies show that up to 50% of patients with an acute myocardial infarction (AMI) do not receive optimal medical care for the condition as set out in guidelines approved by reputable heart organizations and expert consensus.1
This study focuses on provider compliance with seven quality indicators including use of aspirin, reperfusion, beta-blockers, angiotensin converting enzyme (ACE) inhibitors, calcium channel blockers (CCB), and smoking cessation advice for patients having an AMI. Study results showed only 42% of patients received smoking cessation advice, and beta-blockers were prescribed in only 50% of patients for whom they were appropriate. However, aspirin was appropriately used in 76-82% of patients, and CCB were appropriately withheld in 82% of patients. Practitioners are encouraged to review their own protocols for treating AMI.
"Each year approximately 1.5 million people in the U.S. experience acute myocardial infarction (AMI), and approximately one-third of these patients die in the acute phase of the AMI. The annual economic burden of AMI is in excess of $60 billion," say the authors of a study published recently in the Journal of the American Medical Association.1,2 When the Health Care Financing Administration initiated a continuous quality improvement program in 1992 to improve the quality of care for Medicare recipients,3 its first endeavor was called the Cooperative Cardiovascular Project (CCP) and focused on the treatment of acute myocardial infarction (AMI). AMI was chosen because research studies confirm the most effective and beneficial treatment for AMI, and guidelines for directing and standardizing care have been well established. Yet studies show health care providers overlook opportunities to treat AMI or prevent recurrence in 47-50% of patients.1,4
Study Methodology
Through the CCP, researchers developed seven quality indicators and measurable aspects of care as well as eligibility and exclusion criteria based on treatment guidelines from the American Heart Association, American College of Cardiology, and expert consensus.5 These are:
• aspirin prescribed during hospitalization;
• aspirin prescribed at hospital discharge;
• reperfusion using thrombolytics or primary PTCA during first 12 hours of hospitalization;
• beta-blocking agents prescribed at hospital discharge;
• ACE inhibitors prescribed at hospital discharge;
• CCB agents withheld at hospital discharge in patients with impaired left ventricular function defined as ejection fraction less than 40%;
• and smoking cessation advice given to current cigarette smokers.1
Additional data about the quality indicators, variable definitions, and the data extraction software used during the study is available on CCP’s Web site. (See box, p. 55.)
Researchers extracted data from the charts of 186,800 Medicare beneficiaries in 50 states who were hospitalized for AMI during a 17-month period. Subjects were initially identified through the Medicare National Claims History File, which contains bills for treatment submitted by acute care hospitals. The sample had to meet the definition of a confirmed AMI as outlined in the International Classification of Diseases,6 i.e. elevated levels of creatine kinase isoenzyme MB or lactate hydrogenase with LD1 levels greater than LD2 levels or two of these:
• chest pain;
• twofold elevation of the creatine kinase level;
• and electrocardiographic evidence of an AMI.
Although 186,800 charts were examined, researchers evaluated quality indicators only for patients with a first confirmed AMI that occurred during the sampling period and who were considered ideal candidates for the specific therapy. Thus the care would nearly always be indicated for the individuals whose records were reviewed. If important lab data were missing, such as thrombolytic timing values, or if patients had congestive heart failure, they would not be considered ideal candidates for thrombolytic therapy or the use of beta-blockers, respectively. This strategy eliminated any controversy in the interpretation of the compliance to the AMI’s quality indicators.1
The greatest success in compliance among all geographical regions in the United States involves aspirin therapy. The researchers audited aspirin prescribed in the hospital as well as at discharge and found an overall compliance range of 67.8-100% and 82.1- 96%, respectively. The lowest national compliance was with smoking cessation advice for current cigarette smokers, with a range of 7.3-81.7%. The quality indicators’ average percent compliance among all geographic regions is scaled from highest to lowest compliance:
• aspirin during hospitalization (86%);
• CCB agents withheld on discharge in patients with impaired left ventricular function (82%);
• aspirin at discharge (78%);
• reperfusion during first 12 hours (67%);
• ACE inhibitors at discharge (59%);
• beta-blockers at discharge (50%);
• smoking cessation advice (42%).
When analyzing study data, researchers found specific areas of the United States where compliance varied significantly from the national results. (See table, above, showing the geographical compliance with quality indicators for AMI.) The South Central and Southwestern areas of the United States have the lowest compliance in prescribing aspirin during hospitalization, advising smokers to quit, and prescribing beta-blockers to appropriate patients at hospital discharge. The North Central region and the Northeast have the highest compliance in prescribing aspirin and beta-blockers on discharge.
Implications for Practice
This study focuses on the importance of using generally acceptable guidelines as markers for quality. Researchers must be sure guidelines are based on carefully constructed, research-based processes of care for a medical condition that does not have much variance. For greatest efficacy, the guideline compliance research would focus on a frequently occurring, severe medical condition that has guidelines generally accepted by the health care community. Such guidelines are useful for directing and standardizing care and equally useful for evaluating compliance with accepted standards of care.
The authors suggest a rationale explaining why a gap may exist between quality indicators for AMI and the care actually provided. Health care providers may lack knowledge or understanding of approved guidelines, disagree with guideline content, resist change fearing loss of professional autonomy, or have a span of time lapse before medical practice behavior changes in response to new knowledge.1 The authors state: "These gaps between knowledge and practice have important consequences. Acute myocardial infarction is a common and serious condition, and the evidence from clinical trials strongly suggests that adherence to these established guidelines will result in better patient outcomes. It is undoubtedly true that some AMI patients experience unnecessary morbidity and mortality because they receive substandard medical care."1 Practitioners are encouraged to obtain a copy of the current guidelines for care of AMI with an eye to reviewing their own practice protocols.5 v
References
1. O’Connor, GT, Quinton, HB, Traven, ND, et al. Geographical variation in the treatment of acute myocardial infarction: The Cooperative Cardiovascular Project. JAMA 1999;281:627-633.
2. American Heart Association. Heart and Stroke Facts: 1996 Statistical Supplement. Dallas; 996:1-23.
3. Jencks SF, Wilensky GR. The Health Care Quality Improvement Initiative: A new approach to quality assurance in Medicare. JAMA 1992; 268:900-903.
4. McCormick D, Gurwitz J, Lessard D, et al. Use of aspirin, b-blockers, and lipid-lowering medications before recurrent acute myocardial infarction. Arch Intern Med 1999;159:561-567.
5. Gunnar R, Passamani E, Bourdillon P, et al. Guidelines for the early management of patients with acute myocardial infarction: A report of the American College of Cardiology/American Heart Association Task Force on assessment of diagnostic and therapeutic cardiovascular procedures. J Am Coll Cardiol 1990;16:249-292.
6. U.S. Department of Health and Human Services. International Classification of Diseases. Ninth Revision, Clinical Modification. Washington, DC: Public Health Service; 1988.
Subscribe Now for Access
You have reached your article limit for the month. We hope you found our articles both enjoyable and insightful. For information on new subscriptions, product trials, alternative billing arrangements or group and site discounts please call 800-688-2421. We look forward to having you as a long-term member of the Relias Media community.