Comparison of vitreous carbon and elgiloy transvenous ventricular pacing leads.

In a randomized prospective study of 150 patients, we compared two porous-tipped, finned leads, one with a vitreous carbon tip (surface area = 12 mm2) and the other with an Elgiloy tip (surface area = 8 mm2). We assessed the acute and chronic stimulation thresholds and the ease of implantation of the two leads. The acute current thresholds for the vitreous carbon and Elgiloy-tipped leads were 1.7 +/- 0.5 (+/- SD) mA vs. 1.1 +/- 0.4 mA (0.25 ms pulse width), 1.3 +/- 0.5 mA vs. 0.9 +/- 0.3 mA (0.5 ms), and 1.0 +/- 0.3 mA vs. 0.8 +/- 0.3 mA (0.75 ms), respectively (P less than 0.0005). Impedance at implantation was 473 +/- 121 ohms and 716 +/- 285 ohms (P less than 0.0005) for the carbon-tipped and Elgiloy-tipped leads, respectively. The R-wave amplitudes were 10.2 +/- 5.1 volts and 6.8 +/- 3.0 volts, respectively (P less than 0.0005). Both leads were easy to implant and showed low stable chronic thresholds from 3 weeks after implantation, at which time the stimulation threshold was 1.9 +/- 1.0 volts vs. 1.5 +/- 0.6 volts with the implanted voltage-variable generators and 1.8 +/- 0.8 mA vs. 1.6 +/- 0.6 mA with the implanted current-variable generators. Reoperation for displacement was required for two of the 87 (2.3%) carbon-tipped and 2 of the 67 (3.2%) Elgiloy-tipped leads. There was no exit block nor any other lead-related complication. We conclude that both leads have similar and satisfactory performance.