Unexpected high failure rate of a specific MicroPort/LivaNova/Sorin pacing lead

Left Bundle Branch Area Pacing versus Right Ventricular Pacing in Patients with Atrioventricular Block: An Observational Cohort Study

Objective

We aim to conduct a comparison of the safety and effectiveness performance between left bundle branch area pacing (LBBAP) and right ventricular pacing (RVP) regimens for patients with atrioventricular block (AVB).

Methods

This observational cohort study included patients who underwent pacemaker implantations with LBBAP or RVP for AVB indications from the 1st of January 2018 to the 18th of November 2021 at West China Hospital. The primary composite outcome included all-cause mortality, lead failure, or heart failure hospitalization (HFH). The secondary outcome included periprocedure complication, cardiac death, or recurrent unexplained syncope. A 1 : 1 propensity score-matched cohort was conducted for left ventricular (LV) function analysis.

Results

A total of 903 patients met the inclusion criteria and completed clinical follow-up. After adjusting for the possible confounders, LBBAP was independently associated with a lower risk of the primary outcome (OR 0.48, 95% CI 0.28 to 0.83, p = 0.009), including a lower risk of all-cause mortality and HFH. No significant difference in the secondary outcome was detected between the groups except that LBBAP was independently associated with a lower risk of recurrent unexplained syncope. In the propensity-score matching cohort of echocardiographic analysis, the LV systolic dyssynchrony index was lower in LBBAP compared with that in RVP (5.68 ± 1.92 vs. 6.50 ± 2.28%, p = 0.012).

Conclusions

Compared to conventional RVP, LBBAP is a feasible novel pacing model associated with a significant reduction in the primary composite outcome. Moreover, LBBAP significantly reduces the risk of recurrent unexplained syncope and improves LV systolic synchrony. This study is registered with ClinicalTrials.gov NCT05722379.

Prevalence and management of electrical lead abnormalities in cardiac implantable electronic device leads

Background

Electrical lead abnormalities (ELAs) can result in device malfunction, leading to significant morbidity in patients with cardiac implantable electronic devices (CIEDs).

Objective

We sought to determine the prevalence and management of ELAs in patients with CIEDs.

Methods

This was a retrospective cohort study of patients implanted with a CIED between 2012 and 2019 at a tertiary care center. The primary outcome was ELA defined as increased capture threshold (≥2× implantation value), decreased sensing (≤0.5 implantation value), change in impedance (>50% over 3 months), or nonphysiologic potentials. A secondary outcome of device clinic utilization was also collected.

Results

There were 2996 unique patients (35% female) included with 4600 leads (57% Abbott, 43% Medtronic). ELAs were observed in 135 (3%) leads, including 124 (92%) Abbott and 10 (7%) Medtronic leads (hazard ratio 9.25, P < .001). Mean follow-up was 4.5 ± 2.2 years. ELAs were associated smaller lead French size, atrial location, and Abbott leads. Lead revision was required in 28% of cases. Patients with lead abnormalities had 38% more in-clinic visits per patient year of follow-up compared with those without (P < .001).

Conclusion

ELAs were more frequent in certain models, which increased rates of revision and follow-up. Identification of factors that mitigate these abnormalities to improve lead performance are required to improve care for these devices and provide efficient healthcare.

Evolution of tricuspid valve regurgitation after implantation of a leadless pacemaker - a single center experience, systematic review and meta-analysis

Introduction

Conventional transvenous pacemaker leads may interfere with the tricuspid valve leaflets, tendinous chords, and papillary muscles, resulting in significant tricuspid valve regurgitation (TR). Leadless pacemakers (LLPMs) theoretically cause less mechanical interference with the tricuspid valve apparatus. However, data on TR after LLPM implantation are sparse and conflicting. Our goal was to investigate the prevalence of significant TR before and after LLPM implantation.

Methods

Patients who received a leadless LLPM (Micra™ TPS, Medtronic) between May 2016 and May 2021 at our center were included in this observational study if they had at least a pre‐ and postinterventional echocardiogram (TTE). The evolution of TR severity was assessed. Following a systematic literature review on TR evolution after implantation of a LLPM, data were pooled in a random‐effects meta‐analysis.

Results

We included 69 patients (median age 78 years [interquartile range (IQR) 72–84 years], 26% women). Follow‐up duration between baseline and follow‐up TTE was 11.4 months (IQR 3.5–20.1 months). At follow‐up, overall TR severity was not different compared to baseline (p = .49). Six patients (9%) had new significant TR during follow‐up after LLPM implantation, whereas TR severity improved in seven patients (10%). In the systematic review, we identified seven additional articles that investigated the prevalence of significant TR after LLPM implantation. The meta‐analysis based on 297 patients failed to show a difference in significant TR before and after LLPM implantation (risk ratio 1.22, 95% confidence interval 0.97–1.53, p = .11).

Conclusion

To date, there is no substantial evidence for a significant change in TR after implantation of a LLPM.

Leadless atrio-ventricular synchronous pacing in an outpatient setting - early lessons learned on factors affecting atrio-ventricular synchrony

BACKGROUND

Leadless pacemakers (PMs) capable of atrio-ventricular (AV) synchronous pacing have recently been introduced. Initial feasibility studies were promising, but limited to just a few minutes of AV synchronous pacing. Real-world long-term data on AV synchrony and programming adjustments affecting AV synchrony in outpatients are lacking.

OBJECTIVE

To investigate AV synchrony and influences of PM programming adjustments in outpatients with leadless VDD PMs.

METHODS

All patients who received a leadless VDD PM (Micra™ AV, Medtronic, US) between 07/2020 and 05/2021 at our center were included in this observational study. AV synchrony was assessed repeatedly postoperatively and during follow-up using Holter ECG recordings. AV synchrony was defined as a QRS complex preceded by a p-wave within 300ms. The impact of programming changes during follow-up on AV synchrony was studied.

RESULTS

816 hours of Holter ECG from 20 outpatients were analyzed. During predominantly paced episodes (≥80% ventricular pacing), median AV synchrony was 91% (IQR 34-100%) when patients had sinus rates 50-80/min. Median AV synchrony was lower when patients had sinus rates >80/min (33%, IQR 29-46%, p<0.001). During a stepwise optimization protocol, AV synchrony could be improved (p<0.038). Multivariate analysis showed that a shorter maximum A3 window end (p<0.001), a lower A3 threshold (p=0.046), and minimum A4 threshold (p<0.001) improved AV synchrony.

CONCLUSION

Successful VDD pacing in the outpatient setting during higher sinus rates is more difficult to achieve than can be presumed based on the initial feasibility studies. The devices often require multiple reprogramming to maximize AV sequential pacing.

Electrical abnormalities with St. Jude/Abbott pacing leads: A systematic review and meta-analysis

BACKGROUND

Although there is a paucity of contemporary data on pacemaker lead survival rates, small studies suggest that some leads may have higher malfunction rates than do others.

OBJECTIVE

The purpose of this study was to determine the malfunction rates of current pacemaker leads.

METHODS

A meta-analysis including studies that examined the non-implant-related lead malfunction rates of current commercially available active fixation pacemaker leads was performed. An electronic search of MEDLINE/PubMed, Scopus, and Embase was performed. DerSimonian and Laird random effects models were used.

RESULTS

Eight studies with a total of 14,579 leads were included. Abbott accounted for 10,838 (74%), Medtronic 2510 (17%), Boston Scientific 849 (6%), and MicroPort 382 (3%) leads. The weighted mean follow-up period was 3.6 years. Lead abnormalities occurred in 5.0% of all leads, 6.1% of Abbott leads, 1.1% of Medtronic, 1.4% of Boston Scientific, and 5.5% of MicroPort. The most common lead abnormality was lead noise with normal impedance. Abbott leads were associated with an increased risk of abnormalities (relative risk [RR] 7.81; 95% confidence interval [CI] 3.21-19.04), reprogramming (RR 7.95; 95% CI 3.55-17.82), and lead revision or extraction (RR 8.91; 95% CI 3.36-23.60). Abbott leads connected to an Abbott generator had the highest abnormality rate (8.0%) followed by Abbott leads connected to a non-Abbott generator (4.7%) and non-Abbott leads connected to an Abbott generator (0.4%).

CONCLUSIONS

Abbott leads are associated with an increased risk of abnormalities compared with leads of other manufacturers, primarily manifesting as lead noise with normal impedance, and are associated with an increased risk of lead reprogramming and lead revision or extraction.

A Robot Mimicking Heart Motions: An Ex-Vivo Test Approach for Cardiac Devices

Purpose

The pre-clinical testing of cardiovascular implants gains increasing attention due to the complexity of novel implants and new medical device regulations. It often relies on large animal experiments that are afflicted with ethical and methodical challenges. Thus, a method for simulating physiological heart motions is desired but lacking so far.

Methods

We developed a robotic platform that allows simulating the trajectory of any point of the heart (one at a time) in six degrees of freedom. It uses heart motion trajectories acquired from cardiac magnetic resonance imaging or accelero-meter data. The rotations of the six motors are calculated based on the input trajectory. A closed-loop controller drives the platform and a graphical user interface monitors the functioning and accuracy of the robot using encoder data.

Results

The robotic platform can mimic physiological heart motions from large animals and humans. It offers a spherical work envelope with a radius of 29 mm, maximum acceleration of 20 m/s² and maximum deflection of ±19° along all axes. The absolute mean positioning error in x-, y- and z-direction is 0.21 ±0.06, 0.31 ±0.11 and 0.17 ±0.12 mm, respectively. The absolute mean orientation error around x-, y- and z-axis (roll, pitch and yaw) is 0.24 ±0.18°, 0.23 ±0.13° and 0.18 ±0.18°, respectively.

Conclusion

The novel robotic approach allows reproducing heart motions with high accuracy and repeatability. This may benefit the device development process and allows re-using previously acquired heart motion data repeatedly, thus avoiding animal trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13239-021-00566-3.

Long-Term Technical Performance of the Osypka QT-5® Ventricular Pacemaker Lead

Background: Lead-associated complications and technical issues in patients with cardiac implantable electronic devices are common but underreported in the literature. Methods: All patients undergoing implantation of the Osypka QT-5^® ventricular lead at the University Clinic St. Pölten between 1 January 2006 and 31 December 2012 were retrospectively analyzed (n = 211). Clinical data including pacemaker follow-up examinations and the need for lead revisions were assessed. Kaplan–Meier analysis to estimate the rate of lead dysfunction during long-term follow-up was conducted. Results: Patients were followed for a median of 5.2 years (interquartile range (IQR) 2.0–8.7). R-wave sensing properties at implantation, compared to last follow-up, remained basically unchanged: 9.9 mV (IQR 6.8–13.4) and 9.6 mV (IQR 5.6–12.0), respectively). Ventricular pacing threshold significantly increased between implantation (0.5 V at 0.4 ms; IQR 0.5–0.8) and the first follow-up visit (1.0 V at 0.4 ms; IQR 0.8–1.3; p < 0.001) and this increase persisted throughout to the last check-up (0.9 V at 0.4 ms; IQR 0.8–1.2). Impedance significantly declined from 1142 Ω (IQR 955–1285) at implantation to 814 Ω (IQR 701–949; p < 0.001) at the first check-up, followed by a further decrease to 450 Ω (IQR 289–652; p < 0.001) at the last check-up. Overall, the Osypka QT-5^® ventricular lead was replaced in 36 patients (17.1%). Conclusions: This report shows an unexpected high rate of technical issues of the Osypka QT-5^® ventricular lead during long-term follow-up.