Acute left atrial ridge lesion after cryoballoon ablation: How it affects left atrial appendage closure combined procedure?

Background: Acute left atrial ridge (LAR) lesion was observed after atrial fibrillation ablation. However, the feature of LAR lesion has not been quantitatively evaluated and its influence on left atrial appendage closure (LAAC) combined procedure remained to be explored. We aimed to evaluate profile of acute LAR lesion and investigate its influence on LAAC procedure. Methods: LAR lesion profile was measured by transesophageal echocardiography (TEE) in 117 consecutive non-valvular AF patients underwent combined procedure of cryoballoon (CB) ablation and LAAC. Its correlation with baseline variables and clinical outcomes were thoroughly investigated. Results: Measurement of 96 available TEE image series showed 95 had prominent acute LAR lesion, with a greater change in width (Δwidth=3.6±2.3 mm) than thickness (Δthickness=2.6±3.5 mm), and correspondingly narrowed outer ostium (Δouter ostium diameter=-3.4±4.0 mm). While the inner ostium stayed unchanged. Logistic regression analysis showed that a higher nadir temperature when freezing left superior pulmonary vein (LSPV) led to a LAR lesion with greater width (2-fold wider) (adjusted odds ratio =1.16, 95% confidence interval 1.02-1.31). For evaluation of LAAC outcomes, residual flow occurred in 6 patients, 4 with Watchman had minimal residual flow at the inferior border, while 2 with LAmbre developed larger residual flow at the LAR side. Clinical outcomes were similar between groups divided by LAR lesion size. Conclusion: Acute LAR lesion frequently occurred following CB ablation combined procedure, and its width positively correlates with LSPV nadir temperature. It affects measurement of pacifier device but has no influence on plug device when performing combined procedure.