Reassessment of the natural evolution and complications of temporary epicardial wires after cardiac surgery.

Objective: The aim of this study was to prospectively reassess the natural evolution and complications of temporary epicardial wires (TEW) after cardiac surgery.

Design: Observational prospective study.

Setting: Monocentric.

Participants: All adult patients having cardiac surgery with TEW insertion, except for those undergoing cardiac transplantation or having permanent pacemakers.

Interventions: Thresholds were measured daily until wire removal or permanent device insertion. Descriptive statistics and analysis of variance (ANOVA) were performed with p<0.05 as the significance threshold.

Main Results: Two hundred thirty-six patients were enrolled. All had ventricular and only 142 (60%) both ventricular and atrial unipolar FEP15, Ethicon TEW. In most TEW (74%), capture thresholds increased significantly by the first (atrial wires) and by the second (ventricular wires) postoperative day and continued to increase until the fifth day, followed by a plateau. For the others, 2 opposite profiles were noticed: 10% of the total TEW lost their capture function before the fourth postoperative day, whereas 16% remained functional beyond the seventh postoperative day. Both atrial and ventricular sensitivity degraded significantly by the second day. The median energy output used for pacing was 17.5 mA (atrial) and 20 mA (ventricular), regardless of the capture thresholds. Major complications related to TEW were noted in 0.8% of cases.

Conclusion: Despite widespread use, the natural history of TEW is still a major concern. Pacing with high-energy output is a possible factor leading to capture dysfunction that must be avoided. Education of all operators is needed.