Updated recommendations for patients with unstable angina and non-ST elevation myocardial infarction include several major changes in preliminary testing and management, according to the full text guidelines published in the August 14 issue of Circulation.

The American College of Cardiology and the American Heart Association have jointly released revised Guidelines for the Management of Patients with Unstable Angina (UA)/Non-ST- Elevation Myocardial Infarction (NSTEMI).

Major changes to the guidelines include suggesting an initial non-invasive set of preliminary tests, such as a stress test, echocardiogram or radionuclide angiogram, recommending the use of clopidogrel for at least one year after receiving a drug-eluting stent, highlighting the importance of more intense lipid and blood pressure control, and advising cessation of non-steroidal anti-inflammatory drugs for these patients during hospitalization.

The ability to detect and treat these conditions earlier has greatly improved over the last several years. “New evidence from pivotal trials over the past five years has been gathered together in these guidelines to give physicians up-to-date and detailed information on which treatment options will provide the best possible outcomes for their patients,” said Nanette K. Wenger, MD, F.A.C.C., F.A.H.A., a member of the guidelines writing committee and professor of medicine in the Division of Cardiology at Emory University School of Medicine in Atlanta. “This is a major educational document for health professionals, and I trust it will become part of the core teaching for medical students, residents and graduate physicians.”

The guidelines, which were last published in 2002, have been developed for cardiovascular specialists, emergency room physicians and healthcare professionals who evaluate and treat patients with acute coronary syndrome. They focus on the diagnosis, treatment and management of patients with unstable angina and the closely related condition of non-ST segment elevation myocardial infarction.

The 2002 guidelines recommended an early invasive strategy - diagnostic angiography and revascularization. The revised guidelines differentiate more extensively between high- and low-risk patients, and recommend an early invasive strategy for unstable and high-risk patients, with an initial conservative (non-invasive) strategy - stress test, echocardiogram or radionuclide study - as a possible treatment option in stabilized patients and low-risk patients. Risk status is determined by risk scores.

For clinical practitioners, the revised guidelines emphasize secondary prevention, recommendations that should be continued after the patient is discharged from the hospital to reduce risk of a recurrent heart attack. “We are emphasizing the use of angiotensin-converting enzyme inhibitors---drugs that protect the muscle--- and prescribing aldosterone receptor blockade, a new drug category that wasn’t available previously for people with heart failure,” said Wenger. “High-dose antioxidant vitamin supplements such as beta carotene, vitamins E and C and folic acid for secondary prevention are no longer recommended because results from clinical trials have shown no benefit and possible harm.” There is also a greater emphasis on smoking cessation.

Also new in the guidelines is the call for more intense lipid and blood pressure control. More stringent low-density cholesterol-lowering therapy and blood pressure management is recommended, suggesting levels should be kept lower than 100 mg/dL, ideally reduced to 70 mg/dL. Blood pressure should be lower than 140/90; for patients with diabetes or chronic kidney disease, a reading lower than 130/80 is recommended.

Clopidogrel is now recommended for at least one year after placement of a drug-eluting stent and shorter term for bare metal stent and with medical therapy. “In addition we are emphasizing the value of intensive, long-term platelet therapy,” said Wenger.

Additional updates to the guidelines include recommendations to discontinue the use of hormone replacement therapy in postmenopausal women; add troponin biomarkers as markers of cardiac damage and B-type natriuretic peptide markers as potentially useful for cardiac risk assessment.