Leadless pacing in the elderly: exit strategy or valid alternative?
Authors: Parlato A , Barletta V , Tamborrino P P , Parollo M , Mazzocchetti L , Sbragi S , Canu A , Di Cori A , De Lucia R , Segreti L , Bongiorni M G , Zucchelli G 
Published: May 2023

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The need for cardiac pacing progressively increases with age and the elderly constitute a special subset of patients, being often very fragile and at a greater risk for procedural complications. Leadless pacing systems appear to be a safe and effective option, being devoid of most complications associated with traditional transvenous pacing systems.

Purpose
This study aimed to analyze a single-center experience with M-TPS (Micra Transcatheter Pacing System) implantation in terms of safety and efficacy in a long-term follow-up.

Methods
Between May 2014 and November 2022, 193 patients underwent M-TPS implantation in our Center, all patients fulfilled standard criteria for pacemaker implantation with indication to receive either VVI or VDD pacing. We divided the study population into two groups according to age (group 1 &lt; 79 y vs group 2 &gt;= 80 y) and analyzed procedural outcomes, electrical performance of the system at follow-up (FU), rate of procedural major complications and of device-related events at FU.

Results
In 95/193 cases (69 males, 73%) M-TPS was implanted in patients &gt; 80 y. There were no statistically significant differences between groups in baseline characteristics. Implant procedure was successful in all cases and no device-related events were registered during FU. Patients were followed-up for an average of 18 months, up to 7 years.
No differences were observed between groups in procedure duration, single device delivery (group 1 vs group 2: 62.1 vs 69.6%, p=0.17), fluoroscopy time [10 (IQR 6-14) vs 8.5 (IQR 6-12.5) minutes, p=0.27], electrical performance at implant: pacing threshold [0.44 (0.38-0.63) vs 0.5 (0.38-0.75) V/0.24 ms, p=0.39]; impedance [710 (610-840) vs 700 (600-810) Ohm, p=0.56]; R wave amplitude [9.3 (6 -13.5) vs 8.2 (6 -11.9) mV, p=0.68] and at 6 months follow-up : pacing threshold [0.5 (0.38-0.5) vs 0.38 (0.38-0.5) V/0.24 ms, p=0.25]; impedance [580 (500-640) vs 570 (530-680) Ohm, p=0.38]; R wave amplitude [13.2 (9.5-17) vs 9.7 (7.8-16.7) mV, p=0.17].
The only statistically significant difference was found in the percentage of ventricular pacing (Vp%), which was higher in group 2 [5.3 (IQR 0.5-35) vs 38% (IQR 14-83), p=0.001] and stayed higher at a 12 months follow-up [11 (1-53) vs 60% (10-94)], p=0.001). High pacing threshold (&gt;= 1mV@0.24ms) at implant was present in thirty-one patients (14 vs 19%, p=0.43).

Conclusions
As the population ages the incidence of rhythm disturbances raises, increasing the need for cardiac pacing. It is imperative to find a therapeutic solution that suits the elderly offering them high efficacy and a low rate of complications. MTP-S implant is an effective and safe procedure in elderly patients with similar electrical performance and outcomes compared with younger patients at long-term follow-up. While initially thought for patients that could not undergo traditional pacing interventions, MTP-S is now emerging as a valid substitute.