Recommendations Tackle Hypertension in CAD Patients
In general, patients with hypertension and CAD should have their blood pressure (BP) lowered to less than 140/90 mm Hg, with a focus on the use of beta-blockers as first-line therapy, according to a new scientific statement from the American Heart Association (AHA), American College of Cardiology (ACC), and American Society of Hypertension (ASH).
The document, published online March 31, 2015, ahead of print in Hypertension, updates a 2007 AHA statement on the treatment of hypertension in the prevention and management of ischemic heart disease.
According to AHA President Elliott M. Antman, MD, of Brigham and Women’s Hospital (Boston, MA), the update aims to address both a gap in recommendations regarding secondary prevention of hypertension and uncertainty about appropriate BP targets. The latter controversy stems from the December 2013 release of guidance written by a group of experts initially empaneled as the Eighth Joint National Committee (JNC 8) but not ultimately backed by any major organization.
“There’s a lot of confusion in the clinical community about management of blood pressure,” Dr. Antman told TCTMD in a telephone interview, adding that the current update will be referenced in a more comprehensive hypertension guideline being drafted jointly by the ACC/AHA.
Dr. Antman highlighted the importance of controlling hypertension in patients with CAD by pointing to research showing that BP is related to higher risk of fatal CAD starting at levels as low as 115/75 mm Hg. Each increase of 20 mm Hg in systolic pressure (or 10 mm Hg in diastolic pressure) has been associated with a doubling in the risk of fatal CAD.
Evidence from observational studies and RCTs shows that reducing BP lowers cardiovascular risks, according to the statement’s writing committee, which was chaired by Clive Rosendorff, MD, PhD, DScMed, of James J. Peters VA Medical Center (New York, NY).
What Is the Right Target?
Although there remains some controversy about appropriate BP targets, the authors say that “reasonable recommendations can be developed from a synthesis of the results from relevant epidemiological studies, consideration of the theoretical issue of the J curve, data from animal studies, human studies involving surrogate endpoints, and randomized clinical trials targeting different BP goals with cardiovascular events as endpoints.”
The committee recommends lowering BP to below 140/90 mm Hg for most patients with hypertension and CAD, with the caveat that certain patients may benefit from a lower target of less than 130/80 mm Hg. The lower goal may be appropriate for those with a prior stroke/TIA or MI or those who have “CAD risk equivalents” like carotid artery disease, PAD, and abdominal aortic aneurysm.
“We counsel that the BP should be lowered slowly in patients with occlusive CAD with evidence of myocardial ischemia, and caution is advised in inducing decreases in [diastolic BP] to < 60 mm Hg, particularly if the patient is > 60 years of age,” the authors write. “In patients > 80 years of age, a reasonable BP target is < 150/80 mm Hg, although there are no direct data to support this, or any other specific BP goal, in this age group.”
Beta-Blockers Take Center Stage
Most patients will not have problems with standard BP-lowering medications, but beta-blockers should be the first choice in patients with CAD, with additional drug classes added as needed, the document advises.
In a telephone interview with TCTMD, Dr. Rosendorff pointed out that for hypertension uncomplicated by CAD, beta-blockers are less effective than other classes of drugs for preventing cardiovascular events. Thus, most hypertension guidelines have not included them in the list of drugs that should be used as first-line therapy.
“In the case of patients who have established coronary artery disease, we have brought beta-blockers from limbo—where they have been consigned—to center stage,” Dr. Rosendorff said, pointing out that the drugs reduce BP and have a range of other cardioprotective effects.
Beta-blockers “alleviate ischemia and angina primarily as a function of their negative inotropic and chronotropic actions,” the authors note. “The decreased heart rate increases diastolic filling time for coronary perfusion. Beta-blockers also inhibit renin release from the juxtaglomerular apparatus.”
For patients with ACS in particular, beta-blockers “are a cornerstone … because of their ability to reduce both heart rate and BP and thus myocardial oxygen demand.”
CAD and Stable Angina
The statement includes 3 separate sections for managing hypertension in different types of CAD:
- CAD and stable angina
- Heart failure of ischemic origin
For chronic stable angina, the authors recommend treatment with a regimen including a beta-blocker in patients with a history of MI; an ACE inhibitor or angiotensin receptor blocker (ARB) if there is a history of MI, LV systolic dysfunction, diabetes, or chronic kidney disease; and a thiazide or thiazide-like diuretic.
Guidance for using other classes of agents in specific clinical scenarios is included in the statement.
The authors note that “there are no special contraindications in hypertensive patients for the use of nitrates, antiplatelet or anticoagulant drugs, or lipid-lowering agents for the management of angina and the prevention of coronary events, except that in patients with uncontrolled severe hypertension who are taking antiplatelet or anticoagulant drugs, BP should be lowered without delay to reduce the risk of hemorrhagic stroke.”
Acute Coronary Syndromes
In ACS, hypertension treatment should focus on selecting agents “that have an established evidence-base for risk reduction for patients with ACS independently of BP lowering,” Dr. Rosendorff and colleagues write. This includes beta-blockers, ACE inhibitors/ARBs, and—in selected patients—aldosterone antagonists. These medications “should typically be titrated to full doses before other agents that do not have an established evidence base are initiated,” the authors add.
As in other CAD patients, beta-blockers should be the first choice for those with ACS, according to the guidance. “If there is no contraindication to the use of beta-blockers … the initial therapy of hypertension should include a short-acting beta-1-selective beta-blocker without intrinsic sympathomimetic activity (metoprolol tartrate or bisoprolol),” the authors recommend. “Beta-blocker therapy should typically be initiated orally within 24 hours of presentation.”
An IV beta-blocker (esmolol) can be considered for patients with severe hypertension or ongoing ischemia, the authors write, adding the beta-blocker therapy should not be initiated until patients have been stabilized.
“The BP may fluctuate early after ACS; thus, efforts should focus on pain control and clinical stabilization before BP is specifically targeted,” Dr. Rosendorff and colleagues write. Also, they say, BP should be lowered slowly and diastolic pressure should not go below 60 mm Hg “because this may reduce coronary perfusion and worsen ischemia.”
According to the guidance, a lower BP target of less than 130/80 mm Hg at discharge “is a reasonable option” in ACS patients.
Heart Failure of Ischemic Origin
Beta-blockers have established benefits in patients with heart failure. The writing committee states that patients with heart failure related to CAD should preferentially receive 1 of 4 beta-blockers previously shown to reduce mortality: carvedilol, metoprolol succinate, bisoprolol, or nebivolol. The authors add that ACE inhibitors/ARBs, aldosterone receptor antagonists, and thiazide or thiazide-like diuretics have also been shown to improve heart failure outcomes and should be used in this population.
Treatment of hypertension in patients with heart failure and CAD should also include management of risk factors—including dyslipidemia, obesity, diabetes, smoking, and dietary sodium intake—as well as a closely monitored exercise program, the recommendations advise.
Rosendorff C, Lackland DT, Allison M, et al. Treatment of hypertension in patients with coronary artery disease: a scientific statement from the American Heart Association, American College of Cardiology, and American Society of Hypertension. Hypertension. 2015;Epub ahead of print.
- Drs. Antman and Rosendorff report no relevant conflicts of interest.