Beta-Blockers for Rate Control in Tachycardia

Introduction to Beta-Blocker Selection

The European Society of Cardiology recommends beta-blockers as the optimal choice for lowering heart rate while maintaining blood pressure in patients with tachycardia and normal blood pressure, with cardioselective agents preferred over nonselective agents to minimize vasodilation and hypotension risk 1

Esmolol is the preferred agent for acute tachycardia control due to its ultra-short half-life, allowing rapid titration and immediate reversibility if hypotension develops, with an initial bolus of 0.5-1 mg/kg IV over 1 minute and maintenance infusion of 50-300 mcg/kg/min 1
Metoprolol is an excellent alternative for sustained rate control with more predictable blood pressure effects than nonselective agents, administered 2.5-5 mg IV over 2 minutes and repeated every 5 minutes as needed, maximum 15 mg total 1, 3

For hypertensive urgency with tachycardia, labetalol combines alpha and beta blockade, providing rate control while lowering blood pressure through vasodilation, with a dose of 0.25-0.5 mg/kg IV bolus and 2-4 mg/min infusion 1, 4
For acute coronary syndromes, beta-blockers are the agents of choice when tachycardia accompanies myocardial ischemia, with esmolol or metoprolol preferred, and contraindicated if heart rate <60 bpm, systolic BP <100 mmHg, moderate-severe heart failure, or heart block 4, 5

Absolute contraindications to beta-blockers include second or third-degree AV block, decompensated systolic heart failure, active asthma or severe COPD exacerbation, heart rate already <50-60 bpm, and systolic blood pressure <100 mmHg 1, 3
Continuous monitoring is essential when using IV beta-blockers, with heart rate target typically 60-100 bpm, blood pressure watched for drops >20 mmHg systolic, cardiac rhythm monitored for heart block development, and signs of heart failure 1, 2

For sustained rate control after acute management, metoprolol can be used at 25-50 mg PO twice daily, titrated to effect, and atenolol at 25-50 mg PO daily, with avoidance of immediate discontinuation of IV therapy and overlap with oral dosing for 2-4 hours before stopping infusion 2