What is bisoprolol?

Bisoprolol: A Cardioselective Beta-Blocker

Bisoprolol is a highly selective beta-1 adrenoceptor blocking agent (beta-blocker) that reduces mortality and hospitalizations in patients with heart failure and is effective for treating hypertension and angina pectoris. It is one of only three beta-blockers (along with carvedilol and metoprolol succinate) with proven mortality benefits in heart failure patients 1, 2.

Pharmacological Properties

• Selectivity: Bisoprolol is a beta-1 selective (cardioselective) adrenoceptor blocker, primarily affecting cardiac tissue 3
• Cardioselectivity: At doses ≤20 mg, bisoprolol primarily blocks beta-1 receptors in cardiac tissue, with minimal effects on beta-2 receptors in bronchial and vascular musculature 3
• Mechanism: Lacks intrinsic sympathomimetic activity and membrane stabilizing properties 3
• Pharmacokinetics:
  • Bioavailability: ~80% (not affected by food)
  • Half-life: 9-12 hours (longer in elderly due to decreased renal function)
  • Elimination: 50% excreted unchanged in urine, 50% as inactive metabolites
  • Dosing: Once daily (steady state reached within 5 days)

Clinical Applications

1. Heart Failure

Bisoprolol has demonstrated significant mortality benefits in heart failure:

• The CIBIS-II trial showed bisoprolol reduced all-cause mortality by 34% in patients with heart failure 1
• Treatment with bisoprolol resulted in 56% reduction in sudden cardiac death 1
• Reduced all-cause hospital admissions by 20% 1, 4
• Effective across all heart failure severity levels (NYHA class II-IV) 1
• Treating just 23 patients with bisoprolol would prevent 1 death 1

2. Hypertension

• Effectively reduces blood pressure in essential hypertension 5
• Can be used as monotherapy for stage I and II hypertension at doses of 5-10 mg daily 5
• Mean blood pressure reductions from 161.5/104.1 to 137.3/87.9 mmHg after 8 weeks of treatment 5

3. Angina Pectoris

• Effective in stable angina pectoris 6
• Comparable efficacy to atenolol and verapamil 6

Dosing and Administration

• Heart Failure: Start with 1.25 mg daily, gradually titrate to target dose of 10 mg daily 2
• Hypertension: Start with 5 mg daily, may increase to 10 mg if needed 5
• Important: Proper titration is essential, especially in heart failure patients 2

Comparative Efficacy

When compared to other beta-blockers with proven benefits in heart failure:

• Bisoprolol, carvedilol, and metoprolol succinate all reduce mortality in heart failure 1, 2
• Bisoprolol has stronger peak beta-blocking effects than nebivolol and carvedilol 7
• Carvedilol may have additional benefits due to its alpha-blocking properties 1
• In a direct comparison, bisoprolol reduced exercise heart rate by 24% compared to 17% for carvedilol and 15% for nebivolol 7

Adverse Effects and Precautions

• Generally well-tolerated in patients with heart failure 4
• Common side effects include dizziness, bradycardia, hypotension, and fatigue 4
• Unlike non-selective beta-blockers, bisoprolol has fewer effects on bronchial smooth muscle at therapeutic doses 3
• May decrease nocturnal melatonin release (44% reduction), which could potentially affect sleep 7
• Contraindicated in patients with:
  • Severe bronchial asthma
  • Symptomatic bradycardia or hypotension
  • Advanced heart block

Clinical Pearls

• Bisoprolol's high beta-1 selectivity makes it a good choice for patients with mild respiratory disease
• The once-daily dosing improves medication adherence
• Unlike carvedilol, bisoprolol does not significantly impact quality of life scores 7
• In heart failure, never abruptly discontinue bisoprolol; always taper gradually to avoid rebound effects
• Bisoprolol's balanced renal/hepatic clearance makes it suitable for patients with either renal or hepatic impairment

Bisoprolol represents an important therapeutic option for cardiovascular disease management, particularly in heart failure where it has demonstrated significant mortality benefits alongside carvedilol and metoprolol succinate.