Low threshold endocaridal electrodes for permanent cardiac pacing. Comparison between one large and two small surface...

Area of Science:

• Cardiovascular Medicine
• Biomedical Engineering
• Electrophysiology

Background:

• Endocardial electrodes are crucial for cardiac pacing.
• Stimulation thresholds can increase post-implantation, impacting pacing efficacy.
• Optimizing electrode design is essential for stable and effective pacing.

Purpose of the Study:

• To compare stimulation thresholds of three different endocardial electrode designs.
• To evaluate the impact of electrode surface area and configuration on pacing parameters.
• To assess the long-term stability of stimulation thresholds for new electrode designs.

Main Methods:

• Comparative study involving 94 patients and 96 electrodes.
• Measurement of stimulation thresholds using capacitor discharge and constant current pulses.
• Evaluation of electrodes with different surface areas: 47 mm², 6 mm², and a new large contact area-small active surface design.

Main Results:

• The new electrode exhibited lower thresholds (1.7±0.9 V, 1.4±0.8 mA) one month post-insertion compared to conventional electrodes.
• Conventional 47 mm² electrodes showed peak thresholds around day 14 and higher thresholds at one month.
• Stimulation thresholds increased by approximately 20% with reduced impulse duration (2 to 0.5 msec).

Conclusions:

• The novel large contact area-small active surface electrode demonstrates superior performance in maintaining low stimulation thresholds.
• This new electrode design offers advantages in terms of reduced threshold increase and good endocardial adherence.
• The findings suggest potential for improved long-term pacing outcomes with the new electrode technology.