Successful Results of a Bipolar Active Fixation Lead for Atrial Application: An Interim Analysis

Abstract

Adequate atrial lead performance consists of stable sensing and pacing properties. To evaluate whether the CPI 4269 bipolar lead, covered with mannitol (Sweet Tip), in the atrial position encounters these properties, we performed a prospective study of this lead. After complete dissolution of the mannitol helix, mapping of the atrium to obtain the highest electrogram and lowest threshold was followed by screw-in into the endocardium. Intraoperative measurements were performed and long-term follow-up was scheduled every 6 to 12 months to measure threshold and perform an intracardial electrogram. Between February 1993 and December 1996, a total number of 73 leads in the atrial position in a consecutive series of patients was implanted. Implantation was performed in 28 patients receiving an AAIR and 45 patients a DDDR pacemaker. Reason for pacemaker implantation was a third-degree AV block in 37% of patients, type II second-degree AV block in 25%, sick sinus syndrome in 35%, and drug refractory paroxysmal atrial fibrillation following His-bundle ablation in 3%. The intraoperative bipolar atrial electrogram had a mean voltage of 4.25 +/- 2.1 mV. The acute atrial bipolar threshold was 0.63 +/- 0.43 V, and current was 1.35 +/- 0.81 mA at a 1.0-ms pulse duration. The mean acute resistance of the lead was 572 +/- 86 Ohm. After a mean follow-up of 18.3 months, the bipolar intracardial electrogram was 3.37 +/- 2.00 mV, the mean atrial threshold measured at the last outpatient clinic visit was 0.99 +/- 0.74 V and the mean impedance was 640 +/- 127 Ohm. A sensing problem due to traction of the atrial lead occurred in only one patient. Acute and late dislodgement did not occur. The CPI 4269 (Sweet Tip) lead is manufactured with a dissolvable capsule covering the helix tip electrode, permitting a safe passage through the venous system. This interim analysis shows that this lead in the atrial position has favorable acute and chronic results.

Rapid Decline in Acute Stimulation Thresholds with Steroid‐Eluting Active‐Fixation Pacing Leads

“…Despite this, there remains a reluctance to routinely use active‐fixation leads in the ventricle mainly because of concerns regarding both acutely and chronically high stimulation thresholds which have not been confirmed on limited studies 4,17 . There are also concerns regarding electrode perforation particularly with the atrial lead, 18,19 although the chronic use of active‐fixation leads in the atrium is well established 2,20,21 …”

“…4,17 There are also concerns regarding electrode perforation particularly with the atrial lead, 18,19 although the chronic use of active-fixation leads in the atrium is well established. 2,20,21 Previous studies examining the performance of active-fixation leads have not reported on acute changes in stimulation thresholds during the op-erative period. 2,4,7,22,23 The results of lead testing during implantation are critically important in determining whether lead repositioning is required.…”

Straight Screw‐In Atrial Leads “J‐Post Shaped” in Right Appendage Versus J‐Shaped Systems for Permanent Atrial Pacing: A Safety Comparison

“…The problem of atrial lead stability, which was a matter of concern in the early days of dual‐chamber pacing, has been partially solved in recent years by the use of the screw‐in mechanism, both in J‐shaped and straight leads. Encouraging data are available on the safety and performances of screw‐in atrial systems, both with an exposed mannitol‐coated helix and an extendable/retractable helix 1,3,4 . Pre‐J‐shaped leads have been seen to offer an advantage over straight leads in terms of their lower rate of acute dislocations 5 …”

“…Encouraging data are available on the safety and performances of screw-in atrial systems, both with an exposed mannitol-coated helix and an extendable/retractable helix. 1,3,4 Pre-J-shaped leads have been seen to offer an advantage over straight leads in terms of their lower rate of acute dislocations. 5 Recently, a randomized comparative study was carried out on J-shaped leads with and without active-fixation mechanisms.…”