From the Research
Beta blockers should be used at low to moderate doses to treat premature atrial complexes (PACs), as they have been shown to reduce long-term mortality in patients with high-burden and low-burden PACs, as demonstrated in a 2022 study published in Frontiers in cardiovascular medicine 1. The doses of beta blockers used to treat PACs are similar to those used for other cardiac conditions.
- For symptomatic PACs, metoprolol is often prescribed at 25-50 mg twice daily, titrated up to 100-200 mg daily as needed based on symptom control and heart rate response.
- Atenolol can be used at 25-50 mg once daily, increased to 100 mg if necessary.
- Propranolol, a non-selective beta blocker, may be started at 10-20 mg three times daily and increased gradually to 40-80 mg three times daily.
- Bisoprolol is typically initiated at 2.5-5 mg once daily, with a maximum of 10 mg daily. When starting beta blocker therapy for PACs, it's best to begin with a low dose and gradually increase while monitoring for symptom improvement, heart rate control, and side effects such as fatigue, dizziness, or hypotension. Beta blockers work by blocking sympathetic stimulation to the heart, reducing automaticity in atrial tissue and decreasing the likelihood of PACs. They're particularly effective in patients whose PACs are triggered by stress or exercise, as they blunt the sympathetic response. Blood pressure and heart rate should be monitored regularly during dose adjustments, and patients should be advised that full therapeutic effect may take several weeks to develop. The use of beta blockers in PACs is supported by the most recent and highest quality study available, which demonstrated a significant reduction in long-term mortality in patients treated with beta blockers compared to those not treated with beta blockers 1. Other studies have also investigated the use of catheter ablation and antiarrhythmic drug therapy for the treatment of premature ventricular complexes (PVCs) and PACs, but the use of beta blockers remains a cornerstone of treatment for PACs 2, 3, 4, 5.