VDD pacemaker replacement independently of the implanted lead: a prospective study.

Area of Science:

• Cardiology
• Biomedical Engineering

Background:

• Single-lead VDD pacing is a proven, reliable cardiac pacing method.
• A key challenge is replacing VDD pacemakers with compatible devices for existing leads.
• This study addresses the atrial sensing performance of VDD pacemakers with non-dedicated leads.

Purpose of the Study:

• To evaluate the atrial sensing performance of VDD pacemakers when used with chronically implanted, non-dedicated leads.
• To determine the feasibility and reliability of replacing existing VDD pacemakers with new devices designed for a short atrial dipole.

Main Methods:

• 16 patients undergoing VDD pacemaker replacement due to battery depletion were enrolled.
• Pacemakers were replaced with VDD(R) Saphir 3 devices, designed for an 8.6 mm atrial dipole.
• Atrial sensing parameters and P-wave amplitudes were compared between old and new pacemakers.

Main Results:

• All new pacemakers functioned well, with no patient-reported stimulation defects.
• P-wave amplitudes measured by old and new pacemakers were similar (0.64 +/- 0.40 vs 0.73 +/- 0.53 mV).
• Atrial sensing percentage at 1 month improved with the new pacemaker (97 +/- 4% vs 95 +/- 3%), attributed to higher programmed sensitivity.

Conclusions:

• VDD pacemaker replacement with devices designed for a short dipole is feasible, safe, and reliable, irrespective of the implanted lead.
• This approach overcomes a theoretical limitation previously associated with VDD pacing system upgrades.
• The findings support the use of modern VDD pacemakers even with older, non-dedicated leads.