What is the role of beta (beta blockers) blockers, such as metoprolol (metoprolol succinate) and atenolol, in the management of hypertension?

Beta-Blockers for Hypertension

Beta-blockers should NOT be used as first-line therapy for uncomplicated hypertension, but they remain essential when specific compelling indications exist, particularly heart failure with reduced ejection fraction, post-myocardial infarction, or angina pectoris. 1, 2

First-Line Use: Generally Not Recommended

• Atenolol specifically should be avoided as first-line therapy because it is less effective than placebo in reducing cardiovascular events according to the American College of Cardiology 2
• Beta-blockers as a class show inferior stroke prevention compared to other antihypertensive drug classes, with atenolol associated with a 26% higher stroke risk versus other agents 3
• The European Society of Cardiology/European Society of Hypertension guidelines acknowledge that beta-blockers are somewhat less effective than RAS blockers and calcium antagonists in preventing stroke and regressing organ damage such as left ventricular hypertrophy 1
• Beta-blockers tend to increase body weight and facilitate new-onset diabetes, particularly when combined with diuretics 1

Compelling Indications Where Beta-Blockers Are Preferred

Heart Failure with Reduced Ejection Fraction

• Four specific beta-blockers have proven mortality benefit: carvedilol, metoprolol succinate, bisoprolol, and nebivolol 1
• Metoprolol succinate reduced mortality by 34% in the MERIT-HF trial 1
• Carvedilol demonstrated a 65% reduction in mortality across four clinical trials and a 38% mortality reduction at 12 months in the COPERNICUS trial 1
• Bisoprolol showed a 32% reduction in all-cause mortality in CIBIS-II, with sudden deaths reduced by 44% 1
• Carvedilol may be particularly appealing due to additional alpha-blocking properties and more favorable glycemic control 1
• These agents should be used together with ACE inhibitors (or ARBs), diuretics, and aldosterone receptor antagonists 1

Post-Myocardial Infarction and Ischemic Heart Disease

• Beta-blockers are highly effective in preventing cardiovascular events in patients with recent myocardial infarction 1
• They reduce oxygen requirements by blocking catecholamine-induced increases in heart rate, myocardial contractility, and blood pressure 4
• Beta-blockers alleviate ischemia and angina in addition to lowering blood pressure 1

Angina Pectoris

• Beta-blockers are indicated for long-term management of patients with angina pectoris 5
• For stable ischemic heart disease with angina, beta-blockers other than atenolol are preferred 2

Preferred Beta-Blockers When Indicated

When a beta-blocker is needed for hypertension with compelling indications, choose:

• Carvedilol, metoprolol succinate, or bisoprolol as first choices based on mortality data 2
• Nebivolol is an alternative, particularly in elderly patients ≥70 years with heart failure 1
• Avoid atenolol due to inferior cardiovascular outcomes 2, 3

Pharmacokinetic Considerations

• Metoprolol succinate provides superior 24-hour blood pressure control compared to atenolol, with significantly better early morning (12 AM-6 AM) systolic BP reduction (-7 mm Hg vs +3 mm Hg, P=0.03) 6
• Atenolol may not provide effective 24-hour coverage when dosed once daily, potentially explaining inferior outcomes 6
• Newer vasodilating beta-blockers (carvedilol, nebivolol) reduce central pulse pressure and aortic stiffness better than atenolol or metoprolol tartrate 1

Target Blood Pressure

• For patients with heart failure and hypertension, target BP is <130/80 mm Hg, with consideration for lowering to <120/80 mm Hg 1
• Exercise caution when lowering diastolic BP below 60 mm Hg in patients with diabetes or age >60 years due to risk of myocardial ischemia 1

Combination Therapy Strategy

• Beta-blockers can be combined with dihydropyridine calcium channel blockers for persistent hypertension and angina 2
• In heart failure, use beta-blockers together with ACE inhibitors (or ARBs), thiazide diuretics, and aldosterone receptor antagonists 1
• Avoid non-dihydropyridine calcium channel blockers (verapamil, diltiazem) in patients with heart failure 1

Common Pitfalls to Avoid

• Do not use atenolol as first-line therapy for uncomplicated hypertension - it lacks cardiovascular event reduction 2
• Do not assume all beta-blockers are equivalent - only carvedilol, metoprolol succinate, bisoprolol, and nebivolol have proven mortality benefits in heart failure 1
• Recognize that beta-blockers are now known to be safe in COPD and peripheral artery disease, conditions previously considered relative contraindications 1
• Monitor for bradycardia, hypotension, and worsening heart failure when initiating therapy 2