What is the recommended antiplatelet therapy, single or dual, for a patient with a permanent pacemaker for third-degree atrioventricular (AV) block?

Antiplatelet Therapy for Permanent Pacemaker in Third-Degree AV Block

For patients receiving a permanent pacemaker for third-degree AV block without concurrent acute coronary syndrome or recent coronary stenting, single antiplatelet therapy with aspirin alone is appropriate—dual antiplatelet therapy is not indicated for the pacemaker procedure itself.

Primary Recommendation Based on Indication

The question of antiplatelet therapy depends entirely on why the patient needs antiplatelet agents, not on the pacemaker implantation itself:

If No Coronary Artery Disease or Recent ACS:

• Single antiplatelet therapy (aspirin alone) or no antiplatelet therapy is appropriate for isolated third-degree AV block requiring pacemaker implantation 1
• The pacemaker guidelines do not recommend dual antiplatelet therapy for device implantation in the absence of coronary indications 1, 2
• Aspirin monotherapy (if used) provides adequate prophylaxis without significantly increasing bleeding risk during the procedure 3

If Concurrent Acute Coronary Syndrome:

• Dual antiplatelet therapy (aspirin plus P2Y12 inhibitor) for at least 12 months is mandated by the acute coronary syndrome indication, not the pacemaker 4
• The ACC/AHA recommends aspirin plus a P2Y12 inhibitor (clopidogrel, ticagrelor, or prasugrel) for minimum 12 months after ACS 4
• The pacemaker procedure should not alter this established ACS treatment regimen 4, 5

If Recent Coronary Stenting (PCI):

• Dual antiplatelet therapy for minimum 6-12 months depending on stent type and clinical presentation 4, 5
• Drug-eluting stents require minimum 6 months DAPT; ACS with stenting requires minimum 12 months 4, 6

Periprocedural Management for Pacemaker Implantation

Critical Safety Data:

• Continue aspirin and clopidogrel through the pacemaker procedure—significant bleeding complications occurred in only 3.1% of patients, and these were exclusively in patients receiving heparin bridging, not antiplatelet agents 3
• Heparin bridging for warfarin dramatically increases bleeding risk (p<0.0001) and should be avoided when possible 3
• Pocket hematoma requiring revision occurred in only 1.5% of patients on antiplatelet therapy 3

Specific Periprocedural Protocol:

• Aspirin: Continue without interruption 3
• Clopidogrel: Continue without interruption if taken within 5 days of procedure 3
• Warfarin: If anticoagulation is required, consider continuing warfarin rather than bridging with heparin, as heparin bridging markedly increases bleeding complications and hospital length of stay 3

Common Pitfall to Avoid

Do not prescribe dual antiplatelet therapy solely because of pacemaker implantation. The major error is conflating device implantation with coronary intervention—these are separate clinical scenarios with different antithrombotic requirements. Third-degree AV block requiring pacemaker is an electrical conduction problem, not a thrombotic condition requiring DAPT 1, 2.

Decision Algorithm

1. Assess for concurrent coronary indications:

   • Recent ACS (within 12 months)? → DAPT required for ACS, not pacemaker 4
   • Recent PCI with stenting (within 6-12 months)? → DAPT required for stent, not pacemaker 4, 5
   • Stable CAD without recent events? → Single antiplatelet (aspirin) sufficient 3
   • Isolated AV block without CAD? → No mandatory antiplatelet requirement for pacemaker 1

2. If DAPT is required for coronary indication:

   • Continue both agents through pacemaker procedure 3
   • Duration determined by coronary indication (12-30 months for ACS, 6-12 months for elective PCI) 4, 5, 6

3. If only single antiplatelet or none required:

   • Aspirin alone is reasonable if cardiovascular risk factors present 3
   • No antiplatelet therapy is acceptable for isolated conduction disease 1