Percutaneous left atrial appendage occlusion in patients with a cardiac implantable electronic device

This prospective single-center cohort study included consecutive patients scheduled for percutaneous LAAO between 2009 and 2021 in the St. Antonius hospital, the Netherlands. Patients with a CIED with TVL implanted prior to LAAO were selected and compared to all other patients (without CIED) scheduled for LAAO. Stand-alone LAAO procedures and LAAO combined with catheter ablation for AF were included. Data was collected using a web-based database containing patient demographics, medical history, LAAO procedural characteristics, peri-procedural complications, peri-procedural chest X-rays, and measurements on essential CIED integrity parameters before and after LAAO. The study was conducted according to the Declaration of Helsinki and approved by the local ethics committee (MEC-U).

Eligibility for percutaneous LAAO was assessed by the cardio-electrophysiologist. All patients underwent transesophageal echocardiography (TOE) to rule out intracardiac thrombus, evaluate LAA anatomy, and guide the LAAO device implantation. LAAO device type was determined at the discretion of the implanting physician, either WATCHMAN 2.5 (Boston Scientific, Natick, MA, USA), WATCHMAN FLX (Boston Scientific, Natick, MA, USA), or Amplatzer Amulet (Abbott, Minneapolis, MN, USA). The LAAO procedure has been described in detail in previous literature [11]. For patients who underwent a combined LAAO with catheter ablation, catheter ablation was performed prior to LAAO. All patients underwent chest X-ray after LAAO to confirm intracardiac positioning of the LAAO device and rule out TVL displacements before discharge. Procedural success rate was verified by follow-up TOE, or cardiac computed tomography (CT) was performed between 45 days and six months after LAAO.

The main goal was to evaluate safety and feasibility of LAAO in patients with a CIED and to identify differences in peri-procedural complications with patients without a CIED. The efficacy outcome was described as acute procedural success of LAAO, defined as adequate LAA closure according to the manufacturer’s instructions for use; device deployed and implanted in correct position, meeting all release criteria and with no significant peri-device leakage (≤ 5 mm for WATCHMAN devices and ≤ 3 mm for Amplatzer Amulet devices).

The primary safety outcome was the occurrence of peri-procedural complications of LAAO. Peri-procedural complications were defined as any deviation of standard procedure or complication occurring within 7 days after LAAO procedure. The secondary safety outcome was the occurrence of CIED macro or micro lead displacement. Macro lead displacement encompasses pacing failure or untreated arrhythmias in the post-procedural period [12], and was detected visually by comparing lead position on chest X-ray prior to LAAO and after LAAO [13]. To detect possible micro lead displacements, measurements of impedance, threshold, and intracardiac sensing of the different TVL of the CIEDs before and after LAAO were compared [14]. Furthermore, time from venous puncture until TSP, time from venous puncture until sheath removal, fluoroscopy times, and radiation exposure (DAP in Gy·cm²) were measured to evaluate if the presence of TVL prolongs procedure times.

Baseline and procedural characteristics are presented as mean ± standard deviation (SD) or median with interquartile range (IQR) for continuous variables. Differences between variables are examined using Student’s t-test or Mann–Whitney U as appropriate. Categorical variables are presented as numbers with percentages and were compared using the χ² test. The Fisher exact test was used when the expected count was less than 5 in > 20% of all cells. Paired comparisons were analyzed using a paired t-test for normally distributed variables. A p value of 0.05 or less was considered statistically significant. Statistical analyses were conducted using SPSS version 26.0 (Statistical Package for Social Sciences, Chicago, IL, USA).

A total of 276 consecutive patients underwent LAAO, of whom 31 (11%) with a CIED in situ prior to the LAAO procedure (flowchart Fig. 1). Twenty-seven out of 31 (87%) patients had pacemaker leads, 24 of 31 patients had leads in the right atrium, and 7 of 31 patients had defibrillator leads. Specification of the device settings before LAAO can be found in Table 1. Patients with and without CIED were similar regarding gender (p = 0.831) and type of AF (p = 0.736). In both groups, participants were at high risk for thrombotic events (mean CHA₂DS₂–VASc 4.3 vs. 3.8, p = 0.104). Patients with CIED were slightly older (mean age 73.7 ± 5.4 vs. 69.4 ± 8.2, p < 0.001), and bleeding risk was slightly higher (mean HAS-BLED 3.3 ± 1.0 vs. 2.8 ± 1.0, p = 0.022). All baseline characteristics can be found in Table 2.

The procedural success rate of LAAO was 27/31 among CIED patients compared to 232/243 in the control group (87% versus 96%, p = 0.075). All four failed procedures in group I were unsuccessful due to unsuitable anatomy for adequate LAAO meeting all release criteria. The first procedure was terminated since the device could not be anchored in the desired position due to the large size of the LAA. During the second procedure, the diameter of the LAA was very small and the required access route was not obtainable due to angulation of the heart. The third patients’ LAA consisted of a wide base without limbus with an acute turn to a narrow point; no proper landing zone for the device was present. The fourth LAAO procedure failed because of insufficient depth, due to a very proximal bifurcation, which limited deployment of the closure device. The presence of TVL of a CIED was not indicated as a problem by the operating physician in any of the LAAO procedures. The results show no statistical difference in complete closure between the CIED patients (n = 21) compared to patients without CIED (n = 185), versus minimal residual flow (n = 4; n = 29, p value = 0.754). All procedural characteristics presented in Table 3 were comparable between groups, except that patients with a CIED underwent stand-alone LAAO more frequently compared to patients without CIED (74% vs. 45%, p = 0.002). Peri-procedural complications were equally observed in both groups (13.8 vs. 14.7%; p value 1.000). The operating physician did not indicate any complication occurring in patients with a CIED to be related to the presence of TVL. Specifications of all complications observed are described in Table 3.

No macro lead displacements were identified; no visual displacements of the CIED leads were observed at chest X-ray (typical example Fig. 2) and no pacing failure or arrhythmia treatment failure was detected in the post-procedural period. In one patient with a VVI pacemaker that underwent radiofrequency catheter ablation combined with LAAO, the rate-responsiveness mode of the pacemaker was switched off before but not restored after LAAO and the patient developed complaints of fatigue during exercise after LAAO. During the next CIED visit, this problem was detected and solved. Overall, no statistical difference of impedance, threshold, and intracardiac sensing was observed between pre- and post-LAAO measurements, suggesting that no micro lead displacement occurred due to LAAO (Tables 4 and 5). The median duration of lead implantation was 32 months (IQR: 10–57 months) between CIED implantation and LAAO, with a minimum of 2 weeks. The median time of the last pacemaker follow-up before LAAO procedure was 78 days (IQR: 38–145) and 62 days (IQR: 7–125 days) between the first pacemaker follow-up after LAAO procedure.

Several limitations should be considered for interpreting the results of this study. Despite the prospective study design, CIED performance parameters were gathered retrospectively, resulting in some missing data. The limited sample size of the cohort of patients with CIED, missing data, and rare occurrence of procedural complications during LAAO undermine the power of the analysis. Additionally, since the effects of LAAO on CIED macro and micro lead displacement were not assessed at pre-defined time intervals directly before and after LAAO, other factors may have influenced pacemaker integrity parameters. Likewise, later originating subtle CIED parameters disruptions may have been missed due to the limited follow-up time.