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Effective Long‐Term Left Atrial Pacing Using Regular Screw‐In Leads Implanted Within the Coronary Sinus

Passive‐fixation leads positioned inside the coronary sinus (CS) have been found to be effective in LA pacing and sensing, but their use is limited by a high incidence of early and late dislodgment. Since anatomic studies have shown that the proximal part of the CS is surrounded by a relatively thick musculature, the feasibility, safety, and efficacy of acute and chronic coronary sinus pacing via regular screw‐in leads positioned within the first centimeters of the CS were evaluated as compared to passive‐fixation leads. Thirty‐three patients (21 men, age 62 ± 10 years) underwent dual chamber pacemaker implantation with LA pacing obtained via passive‐fixation leads (7 patients) or regular screw‐in leads (26 patients). The former approach was prematurely abandoned because of a high rate of acute and late lead dislodgment (42%). The chronic pacing threshold was 1.7 ± 1.0 V at 0.67‐ms pulse width and 1.47 ± 1.3 V at 0.5‐ms pulse width for passive‐ and active‐fixation leads, respectively. In the CS active‐fixation lead group, no postoperative pericardial effusion, CS lead dislodgment, nor diaphragmatic stimulation were observed. In this last group, steroid eluting leads (14 patients) have a statistically lower pacing threshold than noneluting steroid leads (12 patients) (0.88 ± 0.23 vs 2.29 ± 1.68 V, P = 0.011) at long‐term follow‐up. The use of regular screw‐in leads implanted within the CS allows effective and safe long‐term LA pacing without risk of dislodgment. (PACE 2003; 26:1873–1877)