Closure of foramen ovale triggered by injury to tunnel surfaces of septum primum and secundum

Feasibility and safety of cryoballoon ablation for atrial fibrillation and closing patent foramen ovale without implantation：A pilot study

BACKGROUND

Patent foramen ovale (PFO) affects 20%-34% of adults and is associated with strokes and other disorders. The conventional treatment of PFO-related strokes is a closure procedure. The metal device is associated with some adverse events.

OBJECTIVE

Our aim was to investigate the efficacy and safety of PFO closure using cryoablation without implantation in patients with atrial fibrillation (AF) who underwent pulmonary vein isolation (PVI).

METHODS

We divided the 22 patients with both PFO and AF who underwent PVI via cryoablation into 2 groups: standard PVI + atrial septal (AS) cryoablation group (group 1, n = 11) and standard PVI group (group 2, n = 11). The guidewire accesses the left atrium through the PFO without AS puncture during the procedure. Standard PVI via cryoablation was performed. The cryoballoon was retracted to the right atrium and inflated against the AS post-PVI. Patients in group 1 had cryoablation for 120-150 seconds, whereas patients in group 2 received sham ablation. The co-primary end points were the PFO closure rate and a composite of AF recurrence and stroke/transient ischemic attack (TIA) events.

RESULTS

There were no differences in procedure-related adverse events between the 2 groups. Neither group had an ischemic stroke report at 1-year follow-up. The PFO closure rate at 6 months in group 1 was significantly higher than that in group 2 (7 [63.6%] vs 1 [9.1%]; P = .002). AF recurrence post ablation was comparable in both groups at 3 months (3 [27.3%] vs 1 [9.1%]; P = .269), 6 months (0 vs 0), and 12 months (2 [18.2%%] vs 1 [9.1%]; P = .534) of follow-up.

CONCLUSION

Cryoablation is a safe and effective approach to close PFO in patients with AF undergoing PVI in a single procedure.

Lessons learned from experimental models of cerebrovascular aneurysms to improve endocardial device occlusion of the left atrial appendage

In patients with atrial fibrillation, left atrial appendage (LAA) occlusion devices represent an alternative to anticoagulation but are associated with residual peridevice leaks (PDLs) and device-related thrombi (DRT). Similarly, cerebrovascular aneurysms can be treated with coil embolization, but pericoil leaks represent a significant limitation. In experimental models of cerebrovascular aneurysms, endothelial denudation achieved independently with (1) embolization with radioactive coils, (2) mechanical removal of the endothelium, or (3) radiofrequency ablation was dramatically effective in preventing or eliminating pericoil leaks.

Anatomical, physiological, and blood flow similarities exist between the LAA and saccular aneurysms. Concepts developed in treating aneurysm leaks can be used to treat similar problems in the LAA. Learning from aneurysms, we conceived of a novel technique to denude local endothelium and thus eliminate residual leaks around LAA-occlusion devices. We recently successfully tested this hypothesis in patients with a PDL in a prospective manner in a multicenter study. In this article, we expand on the rationale of the technique developed to close PDLs and potentially also prevent DRTs.

Radiofrequency Energy Applications Targeting Significant Residual Leaks After Watchman Implantation: A Prospective, Multicenter Experience

OBJECTIVES

The aim of this study was to evaluate the efficacy of radiofrequency (RF) energy applications targeting the atrial side of a significant residual leak in patients with acute and chronic evidence of incomplete percutaneous left atrial appendage (LAA) occlusion.

BACKGROUND

RF applications have been proved to prevent recanalization of intracranial aneurysms after coil embolization, thereby favoring complete sealing. From a mechanistic standpoint, in vitro and in vivo experiments have demonstrated that RF promotes collagen deposition and tissue retraction.

METHODS

Forty-three patients (mean age 75 ± 7 years mean CHA₂DS₂-VASc score 4.6 ± 1.4, mean HAS-BLED score 4.0 ± 1.1) with residual leaks ≥4 mm after Watchman implantation were enrolled. Procedural success was defined as complete LAA occlusion or presence of a mild or minimal (1- to 2-mm) peridevice leak on follow-up transesophageal echocardiography (TEE), which was performed approximately 45 days after the procedure.

RESULTS

RF-based leak closure was performed acutely after Watchman implantation in 19 patients (44.2%) or scheduled after evidence of significant leaks on follow-up TEE in 24 others (55.8%). The median leak size was 5 mm (range: 4-7 mm). On average, 18 ± 7 RF applications per patient (mean maximum contact force 16 ± 3 g, mean power 44 ± 2 W, mean RF time 5.1 ± 2.5 minutes) were performed targeting the atrial edge of the leak. Post-RF median leak size was 0 mm (range: 0-1 mm). A very low rate (2.3% [n = 1]) of major periprocedural complications was observed. Follow-up TEE revealed complete LAA sealing in 23 patients (53.5%) and negligible residual leaks in 15 (34.9%).

CONCLUSIONS

RF applications targeting the atrial edge of a significant peri-Watchman leak may promote LAA sealing via tissue remodeling, without increasing complications. (RF Applications for Residual LAA Leaks [REACT]; NCT04726943).