Peri-Device Leaks after Percutaneous Left Atrial Appendage Closure: Clinical Significance and Unmet Diagnostic Needs

Abstract

Oral anticoagulation reduces the ischemic stroke risk in patients with nonvalvular atrial fibrillation (NVAF) but inherently increases the bleeding risk. Percutaneous left atrial appendage occlusion (LAAO) offers an alternative to long-term anticoagulation in patients at risk for cardioembolic events due to underlying atrial fibrillation. Although long-term clinical data remain limited, percutaneous LAAO appears to be a safe and effective means of reducing hemorrhagic stroke and non-procedural-related bleeding events compared to warfarin. Incomplete closure of the LAA resulting in a peri-device leak (PDL) is common after interventions targeting the LAA and has been variably associated with an increased risk of embolic stroke in patients following LAAO. However, the clinical significance of PDL remains unclear, in part, due to variability in the definitions used for PDL, modalities used for the detection of PDL, and the confounding impact of continuing therapeutic anticoagulation in patients found to have PDL on surveillance imaging. In the current review, we examine the association of PDL with ischemic stroke and systemic embolization and explore mechanistic considerations in the development of PDL as they pertain to the unmet need for improving the diagnostic assessment of PDL from an anatomic and physiologic perspective.

A Novel Echocardiographic-Based Classification for the Prediction of Peri-Device Leakage following Left Atrial Appendage Occluder Implantation

“…Like other procedures, LAAO has limitations concerning patient selection and device selection due to anatomical features of the patient. One of the most important challenges is the incomplete closure of the LAA resulting in PDL and inefficient protection from thrombi formation and thus incomplete protection from thromboembolic events [1,9,20].…”

“…In the past, criteria for successful closure of the LAA have ranged from <1 mm up to <5 mm residual flow into the LAA on color Doppler flow [10]. Of note, two large randomized trials of LAAO using the Watchman device have both used the arbitrarily defined <5 mm residual flow as success criteria for LAAO [7,9,10,21,22], while others using the Amplatzer™ Cardiac Plug (ACP) [23] and Amulet device have reported leaks > 5 mm as significant and 1-3 mm as moderate [6]. With the Watchmen device, any PDL on TEE was observed in about 32% of patients at one year (PROTECT) [8].…”

“…It is important to consider that the definition of severe or significant PDL most commonly refers to a defect size of more than 5 mm diameter between device edge and LAA tissue on TEE color Doppler interrogation using a Nyquist limit set around 25 cm/s. Using this definition, significant PDL occurs in 5-20% of patients after endovascular or epicardial closure [4,9,10]. The accurate assessment of residual leaks remains crucial in the decision-making with regard to the best post-procedural management [11].…”

Changes in left atrial appendage orifice following percutaneous left atrial appendage closure using three-dimensional echocardiography

“…(10,19) The nding that patients without peri-device leak tended to have a lower post-device eccentricity index, that is, a more circular LAA ori ce, when compared to those with peri-device leak supports this theory. All leaks were not signi cant (< 5mm) according to previously accepted de nition (20).…”

Changes In Left Atrial Appendage Orifice Following Percutaneous Left Atrial Appendage Closure Using Three-Dimensional Echocardiography

“…(10,19) The nding that patients without peri-device leak tended to have a lower post-device eccentricity index, that is, a more circular LAA ori ce, when compared to those with peri-device leak supports this theory. All leaks were not signi cant (< 5mm) according to previously accepted de nition (20).…”