Aggressive secondary prevention urged in CHD.Updated secondary prevention guidelines pull together the latest data from clinical trials to advocate more aggressive management of patients with coronary heart disease coronary heart disease: see coronary artery disease.
coronary heart disease
or ischemic heart disease
Progressive reduction of blood supply to the heart muscle due to narrowing or blocking of a coronary artery (see atherosclerosis). .
The American Heart Association/American College of Cardiology Guidelines for Secondary Prevention for Patients with Coronary and Other Atherosclerotic Vascular Disease atherosclerotic vascular disease Atherosclerosis, see there : 2006 Update assembles evolving evidence from trials involving the management of key risk factors.
"Physicians may have followed the low-density lipid story but they may not be aware of the recommendations for waist circumference or have a good idea about what to do about ACE inhibitors. This puts it all together, hopefully in a usable manner," said Dr. Sidney C. Smith Jr., chairman of the ACC/AHA writing group.
The new guidelines--an update of the 2001 guidelines--recommend more stringent management of six risk factors in patients with coronary heart disease, along with changes to pharmacologic management. Many of these recommendations may seem familiar to cardiologists.
"If you closely read the literature, you probably already know these things," said Dr. James A. De Lemos, a cardiologist at the University of Texas Southwestern Medical Center in Dallas.
Despite this, the updated changes to lipid management and aspirin therapy in this patient group are worth drawing attention to, he said.
Here's a look at the new guidelines, which advise the following changes to pharmacologic management:
* Lipid management. The goal of less than 100 mg/dL for LDL cholesterol is unchanged, but the guideline adds that further reduction to levels less than 70 mg/dL is reasonable. If triglyceride levels are 200-499 mg/dL, non-HDL cholesterol should be less than 130 mg/dL; further reduction below 100 mg/dL is reasonable.
The lipid management guidelines reflect recommendations made in 2004 by the National Cholesterol Education Program (NCEP NCEP National Cholesterol Education Program ) Adult Treatment Panel, which advised a target LDL LDL - ["LDL: A Logic-Based Data-Language", S. Tsur et al, Proc VLDB 1986, Kyoto Japan, Aug 1986, pp.33-41]. level of less than 100 mg/dL and offered an optional target of 70 mg/dL in patients at very high risk. More recent study results, such as those from the Treating to New Targets (TNT TNT: see trinitrotoluene.
in full trinitrotoluene
Pale yellow, solid organic compound made by adding nitrate (−NO2) groups to toluene. ) and the Incremental Decrease in End Points Through Aggressive Lipid Lowering (IDEAL) studies, show that aggressive lipid-lowering therapy provides significant clinical benefit in patients who have stable coronary heart disease.
"These guidelines reinforce that all patients [with coronary heart disease] should have LDL of less than 100 mg/dL and provide a reasonable target of 70 mg/dL," said Dr. Smith, a professor of medicine and director of the center for cardiovascular science and medicine at the University of North Carolina at Chapel Hill The University of North Carolina at Chapel Hill is a public, coeducational, research university located in Chapel Hill, North Carolina, United States. Also known as The University of North Carolina, Carolina, North Carolina, or simply UNC .
* Antiplatelet an·ti·plate·let
Acting against or destroying blood platelets.
directed against or destructive to blood platelets; inhibiting platelet function. and anticoagulant therapy. Aspirin therapy has been reduced to 75-162 mg/day, down from 75-325 mg/day in all patients, unless contraindicated. The lowering of the aspirin dose for chronic therapy was based largely on antiplatelet trials, which showed that the benefits of aspirin therapy are the same for lower dose regimens (75-80 mg) as for the adult dose (325 mg) but that the risk of bleeding was considerably less for the lower dose, Dr. Smith said.
Following acute coronary syndrome acute coronary syndrome
A sudden, severe coronary event that mimics a heart attack, such as unstable angina.
acute coronary syndrome or percutaneous coronary intervention Percutaneous coronary intervention (PCI), commonly known as coronary angioplasty or simply angioplasty, is a therapeutic procedure to treat the stenotic (narrowed) coronary arteries of the heart found in coronary heart disease. with stent placement, start and continue 75 mg/day of clopidogrel in combination with aspirin for up to 12 months. Therapy for stent recipients, for which the aspirin dosage is 325 mg/day, should last at least 1 month in patients who have received bare-metal stents, at least 3 months in those who have received sirolimus-eluting stents, and at least 6 months in those who have received paclitaxel-eluting stents.
* Renin-angiotensin-aldosterone system blockers. The guidance for these agents has expanded considerably. ACE inhibitors are recommended for indefinite use in all patients with a left ventricular ejection fraction (LVEF LVEF Left ventricular ejection fraction. See Ejection fraction. ) of 40% or less and in those with hypertension, diabetes, or chronic kidney disease Chronic kidney disease (CKD), also know as chronic renal disease, is a progressive loss of renal function over a period of months or years through five stages. Each stage is a progression through an abnormally low and progressively worse glomerular filtration rate, which is unless contraindicated. The use of ACE inhibitors should be considered in all patients.
Angiotensin receptor blockers (ARBs) should be used in patients who are intolerant of ACE inhibitors and have heart failure or have had an MI with a LVEF of 40% or less. The use of ARBs should be considered in other patients who are intolerant of ACE inhibitors. In patients with systolic heart failure systolic heart failure Cardiology Heart failure with a severely reduced systolic function–LV ejection fraction of ≤35%. Cf Diastolic heart failure. , ARB use in combination with ACE inhibitors should be considered.
Aldosterone blockade should be used for post-MI patients--without significant renal dysfunction or hyperkalemia--who are already receiving therapeutic doses of an ACE inhibitor and [beta]-blocker and who have left ventricular ejection fractions of 40% or less, and have either diabetes or heart failure.
Clinical trials have shown the effectiveness of ACE inhibitors in treating patients with LVEF of 40% or less and in those with hypertension, diabetes, or chronic kidney disease. However, the trial results on the effectiveness of ACE inhibitors in lower-risk patients with normal LV function--who had higher usage of other therapies (statins, [beta]-blockers) and who had a greater level of revascularization--is less clear.
"That's why the committee has said that in patients with normal left ventricular function, all patients should be considered as candidates but among those who have undergone revascularization therapy or who have a high use of other therapies known to reduce risk, it's reasonable not to place them on ACE inhibitors," Dr. Smith said.
* [beta]-Blockers. [beta]-Blockers should be started and indefinitely continued in all patients who have had MI, acute coronary syndrome, or left ventricular dysfunction with or without heart failure symptoms unless contraindicated.
Other updated recommendations include the more stringent management of the following risk factors:
* Blood pressure control. The aim is to keep patients' blood pressure under 140/90 mm Hg or less than 130/80 mm Hg in patients with diabetes or chronic kidney disease through lifestyle modification. In patients who do not meet this goal, blood pressure medication should be added as tolerated. Initially treatment should be with [beta]-blockers and / or ACE inhibitors, adding other drugs such as thiazides as needed to achieve target blood pressure.
* Physical activity. The goal is 30-60 minutes of moderate-intensity aerobic activity 5-7 days per week, up from 3-4 days per week, supplemented by an increase in daily lifestyle activities, such as housework and gardening, and resistance training 2 days per week.
* Smoking. Not only should patients completely stop smoking but they also should not be exposed to any environmental tobacco smoke.
* Weight management. Not only should patients aim for a BMI BMI body mass index.
body mass index
Body mass index (BMI)
A measurement that has replaced weight as the preferred determinant of obesity. between 18.5 and 24.9, but also a waist circumference of less than 40 inches for men and less than 35 inches for women. If waist circumference exceeds these values, patients should initiate lifestyle changes and physicians should consider treatment strategies for metabolic syndrome. The initial goal of weight loss should be to reduce body weight by roughly 10% from baseline. Once this goal has been met, further weight loss can be attempted if indicated.
* Flu vaccine. All patients with cardiovascular disease should receive inactivated influenza vaccinations because these individuals are at increased risk for complications from influenza.
The guidelines make a point of noting that ethnic minorities, women, and the elderly are underrepresented in many trials and urge greater participation by these populations in clinical trials to provide additional evidence about the best therapeutic strategies for these groups.
"Having worked in this area for 15 years ... I think that it is very important that trials include older patients, that the trials include a high percentage of women ... and that they recruit ethnic minorities, because I think that even though it seems logical to assume that the therapies may work, we need the evidence to really strengthen the basis for these recommendations," Dr. Smith said.
The complete guidelines are available in the Journal of the American College of Cardiology (J. Am. Coll. Cardiol. 2006; 47:2130-2139).
BY KERRI WACHTER