Peri-device leakage not CHA2DS2-VASc is associated with post-left atrial appendage closure cardiovascular event

Risk factors, clinical implications, and management of peridevice leak following left atrial appendage closure: A systematic review

BACKGROUND

Left atrial appendage closure (LAAC) is a treatment modality for stroke prevention in patients with atrial fibrillation (AF). One of the potential complications of LAAC is a peri-device leak (PDL), which could potentially increase the risk of thromboembolism formation.

METHODS

This systematic review was done according to PRISMA guidelines. Using four databases, all primary studies through April 2022 that met selection criteria were included. Outcomes of interest were studies reporting on PDL characteristics, risk factors and management.

RESULTS

A total of 116 studies met selection criteria (97 original studies and 19 case reports/series). In the original studies (n = 30,133 patients), the weighted mean age was 72.0 ± 7.4 years (57% females) with a HAS-BLED and CHA2DS2-VASc weighted means of 2.8 ± 1.1 and 3.8 ± 1.3, respectively. The most common definition of PDL was based on size; 5 mm: major, 3-5 mm: moderate, < 1 mm minor, or trivial. Follow up time for PDL detection was 7.15 ± 9.0 months. 33% had PDL, irrespective of PDL severity/size, and only 0.9% had PDL of greater than 5 mm. The main risk factors for PDL development included lower degree of over-sizing, lower left ventricular ejection fraction, device/LAA shape mismatch, previous radiofrequency ablation, and male sex. The most common methods to screen for PDL included transesophageal echocardiogram and cardiac CT. PDL Management approaches include Amplatzer Patent Foramen Ovale occluder, Hookless ACP, Amplatzer vascular plug II, embolic coils, and detachable vascular coils; removal or replacement of the device; and left atriotomy.

CONCLUSION

Following LAAC, the emergence of a PDL is a significant complication to be aware of. Current evidence suggests possible risk factors that are worth assessing in-depth. Additional research is required to assess suitable candidates, timing, and strategies to managing patients with PDL.

Residual leaks following percutaneous left atrial appendage occlusion and outcomes: a meta-analysis

BACKGROUND AND AIMS

Residual leaks are not infrequent after left atrial appendage occlusion. However, there is still uncertainty regarding their prognostic implications. The aim of this study is to evaluate the impact of residual leaks after left atrial appendage occlusion.

METHODS

A literature search was conducted until 19 February 2023. Residual leaks comprised peri-device leaks (PDLs) on transoesophageal echocardiography (TEE) or computed tomography (CT), as well as left atrial appendage patency on CT. Random-effects meta-analyses were performed to assess the clinical impact of residual leaks.

RESULTS

Overall 48 eligible studies (44 non-randomized/observational and 4 randomized studies) including 61 666 patients with atrial fibrillation who underwent left atrial appendage occlusion were analysed. Peri-device leak by TEE was present in 26.1% of patients. Computed tomography-based left atrial appendage patency and PDL were present in 54.9% and 57.3% of patients, respectively. Transoesophageal echocardiography-based PDL (i.e. any reported PDL regardless of its size) was significantly associated with a higher risk of thromboembolism [pooled odds ratio (pOR) 2.04, 95% confidence interval (CI): 1.52-2.74], all-cause mortality (pOR 1.16, 95% CI: 1.08-1.24), and major bleeding (pOR 1.12, 95% CI: 1.03-1.22), compared with no reported PDL. A positive graded association between PDL size and risk of thromboembolism was noted across TEE cut-offs. For any PDL of >0, >1, >3, and >5 mm, the pORs for thromboembolism were 1.82 (95% CI: 1.35-2.47), 2.13 (95% CI: 1.04-4.35), 4.14 (95% CI: 2.07-8.27), and 4.44 (95% CI: 2.09-9.43), respectively, compared with either no PDL or PDL smaller than each cut-off. Neither left atrial appendage patency, nor PDL by CT was associated with thromboembolism (pOR 1.45 and 1.04, 95% CI: 0.84-2.50 and 0.52-2.07, respectively).

CONCLUSIONS

Peri-device leak detected by TEE was associated with adverse events, primarily thromboembolism. Residual leaks detected by CT were more frequent but lacked prognostic significance.

Pattern of Endothelialization in Left Atrial Appendage Occluder by Optic Coherence Tomography: A Pilot Study

BACKGROUND

Implantation of the left atrial appendage occluder (LAAO) has been proven to prevent stroke effectively in patients with atrial fibrillation who cannot tolerate anticoagulants. Incomplete endothelization of LAAO may cause device-related thrombus, and currently no good image modality exists to clearly see LAAO endothelialization. We aimed to use coronary optic coherence tomography (OCT) to visualize LAAO endothelialization.

METHODS AND RESULTS

We enrolled 14 patients (72.8±9.4 years old) undergoing pulmonary vein isolation with a preexisting LAAO implanted more than 1 year ago (5 Watchman and 9 Amulet). After pulmonary vein isolation, we did OCT via steerable sheath and coronary guiding catheter to adjust OCT probe location and injected contrast medium to visualize the LAAO surface. In vitro testing was also performed to see the bare occluder. In vitro OCT showed the surface of the bare device as an interrupted granule pattern, which included the Watchman surface polytetrafluoroethylene membrane string, Amulet disc metal strut, and inner polytetrafluoroethylene membrane string. In the implanted Watchman, OCT showed endothelialization as a smooth surface layer with noninterrupted coarser granules. In the implanted Amulet, OCT showed endothelialization as thin (early) or thick (late) endothelialization layer covering struts with OCT shadows. Among patients with Watchman, 2 showed no, 2 early, and 1 complete endothelialization. Among patients with Amulet, 2 showed no, 3 early, and 4 late endothelialization.

CONCLUSIONS

We demonstrated the feasibility of OCT to visualize LAAO endothelization with high resolution. Further studies are needed to determine antithrombotic regimens if incomplete endothelization is detected. A new OCT catheter may be designed specifically for LAAO.

Impact of pre-existing left atrial appendage occluder on catheter ablation of atrial fibrillation

BACKGROUND

Patients with drug-refractory atrial fibrillation (AF) and pre-existing left atrial appendage occluder (LAAO) device may need pulmonary vein isolation (PVI). In this pioneer study, we investigated the impact of pre-existing LAAO on AF substrates and outcomes of PVI.

METHODS

From our AF registry, 65 drug-refractory patients with LAAO (72.1±11.4 years old; CHA₂DS₂-VASc score 3.7±2.1) were included for PVI. A balanced control group with 124 patients without LAAO receiving PVI (70.9±10.2 years old, CHA₂DS₂-VASc 3.6±1.9) were included for comparison.

RESULTS

We found PVI is feasible in patients with AF with pre-existing LAAO without new peridevice leak. Two patients with LAAO and one without LAAO had stroke during the procedure (2/65 vs 1/124, p=0.272). Complete isolation of left-sided PVs might not be achieved if the device covered the ridge joining the left atrial (LA) appendage to the body of LA. Local electrogram could be detected over LAAO and there was propagation of conduction over the occluder either under sinus rhythm or under atrial arrhythmia. LAAO might modulate LA substrate and induce peridevice fibrosis, peridevice LA flutter and complex fractionate atrial electrogram. The AF recurrent rate at 1 year was similar between the two groups (9.2% vs 8.8%).

CONCLUSIONS

This pioneer study first showed impacts of LAAO on LA substrate and PVI procedure.