Three‐Year Clinical Experience with a New Endocardial Screw‐In Lead with Introduction Protection for Use in the Atrium and Ventricle

Abstract

There is still a high incidence of dislodgement, threshold rises, and loss of sensing with permanent transvenous endocardial leads. Atrial leads are an even greater problem and require particularly reliable methods of fixation. In March, 1976 we reported our preliminary results from animal experiments using a new transvenous screw-in lead with introduction protection. This lead differs from other screw-in models as its spiral tip is retracted in the insulating tube during insertion. For fixation purposes a torque is applied to the proximal end of the conductor coil, which is loosely positioned within the tube, and this moves the helical electrode forward. One hundred and fifty endocardial electrodes have been implanted; 127 of them in the dilated ventricle and 23 in the atrium. The technique of introducing the lead into the vein (cephalic or jugular) was the same as that for conventional leads. It was easy to manage and quite uncomplicated. The fixation features in the atrium or the ventricle were sufficiently reliable to allow some patients to go home several hours post-implant. The total working time of the leads used has been 900 months; the overall complication rate is 2%.

Randomized Comparison of J‐Shaped Atrial Leads with and without Active Fixation Mechanism

“…Dislocation (“macro‐dislodgement”) was observed in only two patients (1% of study cohort). The AF mechanism was intended to provide lead stability, especially in the dilated right atrium and/or in an unusual lead position 4,9,10 . We previously demonstrated a higher dislodgement rate with straight atrial leads compared to J‐shaped leads, despite the use of an AF mechanism in both groups.…”

“…Dual chamber (atrio‐ventricular) pacing systems are employed most frequently in contemporary clinical practice; atrial leads are utilized in over 60% of pacemaker implants in the USA 1 . The problem of atrial lead stability, a matter of concern during the early days of dual chamber pacing, 2 has now been partially solved by the use of an active fixation (screw‐in) mechanism, J‐shaping of the lead, or their combination 3–13 . We previously demonstrated that J‐shaped leads have an advantage over straight leads due to a lower rate of acute dislocations, despite the use of active fixation in both groups 8 .…”

Long‐Term Performance of Screw‐In Atrial Pacing Leads: A Randomized Comparison of J‐Shaped and Straight Leads

“…Dual‐chamber (atrio‐ventricular) pacing systems are used most frequently in contemporary clinical practice; atrial leads are utilized in over 60% of pacemaker implants in the United States 1 The problem of atrial lead stability, a matter of concern during the early days of dual‐chamber pacing, 2 has now been partially solved by the use of an active fixation (screw‐in) mechanism and/or J‐shaping of the lead 3–7 . The relative roles of these two features regarding stable long‐term lead performance, has not yet been fully investigated.…”

“…Dual-chamber (atrio-ventricular) pacing systems are used most frequently in contemporary clinical practice; atrial leads are utilized in over 60% of pacemaker implants in the United States 1 The problem of atrial lead stability, a matter of concern during the early days of dual-chamber pacing, 2 has now been partially solved by the use of an active fixation (screw-in) mechanism and/or Jshaping of the lead. [3][4][5][6][7] The relative roles of these two features regarding stable long-term lead performance, has not yet been fully investigated. We previously reported the short-term results of a randomized, controlled trial comparing active fixation J-shaped (JL) to straight atrial leads (SL) (both with screw-in active fixation mechanisms), 8 which demonstrated more favorable results with the use of JL, due to a lower incidence of lead dislodgment shortly after implantation.…”

Modern atrial and ventricular leads for permanent cardiac pacing.

“…There are relatively few data published with respect to screw-in leads implanted in the atrium, but Bisping et al 13 have implanted 23 leads of the 6957 type with no displacements and a 2% incidence of sensing problems, while Santini et al 14 have reported one displacement out of 30 leads implanted (6957 and Osypka FY61). Both authors have also confirmed the much lower acute atrial thresholds seen with these leads compared with passive leads such as the "J".…”