A new type of endocardial bipolar pacing lead has been designed to ove
rcome the potential drawbacks of the conventional coaxial bipolar paci
ng lead. We prospectively evaluated the new co-radial bipolar pacing l
eads (Intermedics Thin-Line), which are thinner (5 Fr vs 6-8 Fr) than
standard coaxial bipolar leads. X-ray visibility and lead handling wer
e subjectively assessed (excellent, good, adequate, or poor) at implan
t; lead impedance, sensitivity threshold, and pacing threshold were me
asured at implant, then at 1, 3, 6, 12, and 18 months. The results wer
e as follows: 103 patients (51 M; age 63.8 +/- 17.4 years) received 71
atrial (A) and 89 ventricular (V) leads. X-ray visibility was excelle
nt in 59/103; good in 23/103; adequate in 11/103; and poor in 10/103.
Overall handling was excellent in 56/71 A and 69/89 V; good in 11/71 A
and 18/89 V; adequate in 3/71 A and 1/89 V; poor in 1/71 A and 1/89 V
. There were two perioperative complications. At implant: impedance in
A and V were 370.1 +/- 74.7 and 501.5 +/- 124.4 Omega, sensing thresh
olds in A and V were 3.0 +/- 1.5 and 9.9 +/- 5.0 mV, pacing thresholds
at 0.45 ms in A and V were 0.59 +/- 0.21 and 0.41 +/- 0.15 volt, resp
ectively. At 1, 3, 6, 12, and 18 months of follow-up: no pacing lead r
elated complications were reported; pacing lead characteristics remain
ed outstanding and stable. This new lead appears to have significant c
linical advantages over the conventional coaxial bipolar pacing lead.
Long-term follow-up is required to confirm its reliability and chronic
performance characteristics.