CRT43: CHARACTERISTICS OF ACTIVE RVOT ELECTRODES IN CRT & NON-CRT PATIENTS

Abstract

Background

Handling and electrical characteristics of active fixation leads implanted in the RV outflow tract (RVOT) are compared in pts with CRT vs. NON-CRT pts, who received a pacemaker for symptomatic brady-cardias. The CRT patients are part of the Bright-study or its pilot-phase.

Patients

age and gender for CRT (n=47) vs NON-CRT (n=24): 69±9 vs 71±8 years, female: 11/47 vs. 8/24. CRT pts: NYHA class 3,0±0,3; EF 24± 6%; NONCRT: sick sinus (n=6) and AV block (n=18).

Methods

In the most pts ELOX^* or SELOX^* leads were used. All leads have active fixation with an electrically active screw and the SELOX has a steroid eluting tip. Positioning attempts and complications were noted. Electrical parameters were measured with the ERA 300B^* at implant or via the PHILOS^*, PROTOS^* or STRATOS^* (^*=Biotronik) pacemaker: R-wave amplitudes (Rwa), pacing threshold (Thr) and impedances (Imp).

Results

For positioning of the lead at the OT 2.4 ± 2.2 (1-10) vs. 1.8 ± 1.5 (1-6; p=NS) attempts were needed. Rwa for CRT and NON-CRT are respectively 14.2 ± 8.9 vs. 15.1 ± 8.9 mV (p=NS). During follow Rwa decreased a little (average 12,5 mV). Thr for CRT and NON-CRT are similar; CRT 0.7 ± 0.7 vs. NON-CRT: 0.7 ± 0.3 Volt (p=NS). Also during follow up: no difference in pacing Thr. Imp were also similar in the CRT group 627 ± 187 vs the NON-CRT group: 719 ± 268 Ohm (p=NS). Two non-steroid leads (ELOX) had to be repositioned because of a very high pacing threshold (1 CRT; 1 NON-CRT). Two leads (CRT) dislocated early and were repositioned. In 2 CRT-pts advanced AV block occurred during active fixation at RVOT. Conduction recovered < 4 months.

Conclusion

The electrical parameters of RVOT leads are good and are similar for the CRT and NON-CRT patients. Implantation is successful in all patients and complications may occur, but are at a low acceptable level