Bachmann's bundle-ridge related biatrial tachycardia with a long epicardial circuit

Biatrial tachycardia (BiAT), involving Bachmann's bundle in the circuit, has sometimes been observed after mitral anterior line ablation. In this article, we present a case of BiAT, involving a long epicardial circuit, composed of Bachmann's bundle and the left atrial ridge (LAR). We discuss the optimal ablation technique for this tachycardia based on our experience in addition to the relationship between Bachmann's bundle and the LAR. Furthermore, the evaluation method for the mitral anterior block line is also discussed.

Acute left atrial ridge lesion after cryoballoon ablation: How does this affect left atrial appendage closure combined procedure?

BACKGROUND

Acute left atrial ridge (LAR) lesions have been observed following atrial fibrillation (AF) ablation. However, LAR lesions had not yet been quantitatively evaluated and their influence on procedure combining cryoballoon (CB) ablation with left atrial appendage closure (LAAC) remained to be explored.

METHODS

The profile of LAR lesions was measured by transesophageal echocardiography (TEE) in 117 consecutive nonvalvular AF patients, who underwent the combined procedure of CB ablation and LAAC. We thoroughly investigated how LAR lesions correlated with baseline variables and clinical outcomes.

RESULTS

A total of 95 out of 96 available TEE images presented prominent acute LAR lesions. In terms of dimensions, there was a greater change in width (Δwidth = 3.6 ± 2.3 mm) than the thickness (Δthickness = 2.6 ± 3.5 mm), and the outer ostium was narrowed (Δouter ostium diameter = -3.4 ± 4.0 mm), while the inner ostium remained unchanged. A higher nadir temperature when freezing the left superior pulmonary vein (LSPV) led to an LAR lesion with a two times greater width (adjusted odds ratio = 1.16; 95% confidence interval, 1.02-1.31). In the evaluation of LAAC outcomes, four patients implanted with Watchman devices had minimal residual flow at the inferior border, while two implanted with LAmbre devices developed residual flow at the LAR side. Clinical outcomes were similar between groups divided by lesion size.

CONCLUSION

Acute LAR lesions frequently occurred following the CB ablation combined procedure, and lesion width positively correlates with LSPV nadir temperature. The presence of these lesions affects the measurement of pacifier devices but has little impact on that of occluder devices.