Interatrial distance predicts the necessity of additional carina ablation to isolate the right-sided pulmonary veins

Abstract

BACKGROUND Ablation of the pulmonary vein (PV) carina is occasionally required for PV isolation (PVI). Marshall bundle and epicardial connections between the right-sided PV (RtPV) carina and right atrium (RA) may be one of the mechanisms that necessitates carina ablation.OBJECTIVE We sought to clarify anatomical characteristics predictive of the necessity of carina ablation.METHODS Forty-five consecutive patients undergoing radiofrequency catheter ablation of atrial fibrillation were prospectively included in this study. Left atrial (LA) and PV size and morphology, and interatrial distance in the posterior aspect, were measured on cardiac computed tomography (CT) images.RESULTS For right-sided PVI, the patients were divided into 2 groups based on the necessity of RtPV carina ablation, Carina-ABL group (n 5 21) and Non-Carina-ABL group (n 5 24). The distance between the anterior portion of the RtPV carina and RA was shorter in the Carina-ABL group vs in the Non-Carina-ABL group (7.7 6 1.7 mm/m 2 vs 9.5 6 2.3 mm/m 2 ; P 5 .005), whereas other anatomical parameters (LA and RA volumes, right inferior PV angle, and ostial diameters of the RtPVs) did not differ between the groups. For leftsided PVI, the ostial diameter and circumference of the left superior PV were smaller in the Carina-ABL group (n 5 13) vs the Non-Carina-ABL group (n 5 32) (8.6 6 2.1 mm/m 2 vs 7.3 6 1.5 mm/m 2 ; P 5 .044, and 34.9 6 6.0 mm/m 2 vs 30.1 6 5.1 mm/m 2 ; P 5 .017, respectively).CONCLUSIONS A shorter interatrial distance for right-sided PVI and a smaller PV ostium for left-sided PVI were associated with the necessity of additional carina ablation. The presence and location of the epicardial fibers may be affected by the atrial and PV geometry.

Fast anatomical mapping of the carina and its implications for acute pulmonary vein isolation

“… 7 , 8 , 9 Therefore data referring to electrical and anatomical characteristics of the carina region have been published recently. 10 , 11 In our present study, we observed frequency and distribution of carina‐related PV conduction after encircling of ipsilateral PVs during PVI. Furthermore, we hypothesized that carina width can be measured utilizing a fast anatomical mapping (FAM) of the LA and its conjunctive PV, which is generated routinely during PVI.…”

“…Several studies have hinted toward a role of the intervenous carina for persistent conduction between pulmonary veins (PV) and the left atrium (LA) due to an epicardial connection between the carina region and both atria 7‐9 . Therefore data referring to electrical and anatomical characteristics of the carina region have been published recently 10‐11 . In our present study, we observed frequency and distribution of carina‐related PV conduction after encircling of ipsilateral PVs during PVI.…”

A simple pacing maneuver to unmask an epicardial connection involving the right‐sided pulmonary veins

“…Patel et al 6 electrophysiologically provided a proof of this EC in their case series, which demonstrated electrical isolation of right‐sided PVs by ablation at the RA posterior wall. Recently, we added novel electrophysiological and anatomical analyses advancing this suggestion and interpretation 7,9 . The presence of a conduction breakthrough at the carina region during SR highly predicted the necessity of carina ablation 7 .…”

“…Radiofrequency energy was delivered at a power of 25–35 W at the posterior aspect, at 15–20 W at the sites adjacent to the esophagus, and at 30 to 40 W at the anterior aspect of the PV antrum. Target values of the ablation index (Biosense‐Webster) were 500 for the anterior aspect and 400 for the posterior aspect of the PV antrum, and the inter‐lesion distance was 4 mm 8,9 . PVI with entrance and exit blocks was confirmed with the Lasso catheter and a pacing maneuver within the isolation line with an ablation catheter 10 .…”

Epicardial Connections as Intra-Atrial Conduction Routes in a Patient With Advanced Atrial Remodeling

“…Pulmonary vein (PV) isolation is widely applicable as an effective treatment for atrial fibrillation (AF). Electrophysiologists occasionally encounter right-sided PVs (RtPVs) that are difficult to isolate without ablation in the PV carinal area, thus suggesting the presence of an epicardial connection (EC) between the RtPV carina and the right atrium (RA) ( 1 , 2 , 3 , 4 , 5 , 6 , 7 ).

Learning Objectives

To recognize IAC injuries in patients with atrial remodeling associated with AF.

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