A 76-year-old woman reports episodic dizziness and two syncopal spells. Holter monitoring shows intermittent sinus bradycardia at 35 bpm alternating with runs of atrial fibrillation at 140 bpm, plus a sinus pause of 4.2 seconds after termination of one AF run. What is the most appropriate management?

• A Increase rate-control medication and reassess
• B Carotid sinus massage as a diagnostic and therapeutic manoeuvre
• C Ivabradine to increase the sinus rate
• D Permanent pacemaker implantation, with anticoagulation for the AF ✓

Explanation

This is tachy-brady syndrome (sick sinus syndrome variant): periods of severe sinus bradycardia or sinus pauses alternate with atrial tachyarrhythmias. Pauses longer than 3 seconds with symptoms are a class I pacing indication. Pacemaker implantation also permits safe use of rate-controlling and rhythm-controlling drugs, which often cannot be tolerated otherwise. Ivabradine slows the sinus node and would worsen bradycardia, and anticoagulation is still required for the AF component based on stroke risk.

Reference: Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 12th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.