Impact of Radiofrequency Ablation of Atrial Fibrillation on Pulmonary Vein Cross Sectional Area: Implications for the Diagnosis of Pulmonary Vein Stenosis

The effect of left atrial wall thickness and pulmonary vein sizes on the acute procedural success of atrial fibrillation ablation

Nowadays, a novel contact-force guided ablation technique is used for enclosing pulmonary veins in patients with atrial fibrillation (AF). We sought to determine whether left atrial (LA) wall thickness (LAWT) and pulmonary vein (PV) dimensions, as assessed by cardiac CT, could influence the success rate of first-pass pulmonary vein isolation (PVI). In a single-center, prospective study, we enrolled consecutive patients with symptomatic, drug-refractory AF who underwent initial radiofrequency catheter ablation using a modified CLOSE protocol. Pre-procedural CT was performed in all cases. Additionally, the diameter and area of the PV orifices were obtained. A total of 1034 LAWT measurements and 376 PV area measurements were performed in 94 patients (mean CHA2DS2-VASc score 2.1 ± 1.5, mean age 62.4 ± 12.6 years, 39.5% female, 38.3% persistent AF). Mean procedure time was 81.2 ± 19.3 min. Complete isolation of all PVs was achieved in 100% of patients. First-pass isolation rate was 76% and 71% for the right-sided PVs and the left-sided PVs, respectively. No difference was found regarding comorbidities and imaging parameters between those with and without first-pass isolation. LAWT (mean of 11 regions or separately) had no effect on the acute procedural outcome on logistic regression analysis (all p ≥ 0.05). Out of all assessed parameters, only RSPV diameter was associated with a higher rate of successful right-sided first pass isolation (OR 1.01, p = 0.04). Left atrial wall thickness does not have an influence on the acute procedural success of PVI using ablation index and a standardized ablation protocol. RSPV diameter could influence the probability of right sided first-pass isolation.

Relationship between the time point of left atrial size change and the outcomes of radiofrequency catheter ablation

PURPOSE

The change in the left atrial anteroposterior diameter (LAD) after radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) has become an independent factor in predicting the postoperative curative effect; however, whether the specific time point of this change is related to the postoperative curative effect is unclear. The purpose of this study was to explore the correlation between the specific time point of LAD change and the recurrence of AF 1 year after RFCA.

METHODS

Patients with AF who underwent RFCA in our hospital from July 2016 to May 2020 were enrolled in the study. The patients were divided into four groups according to the time point when the LAD decreased by 10% after RFCA: group A, first month after RFCA; group B, second month after RFCA; group C, third month after RFCA; group D, unchanged or changed > 3 months after RFCA.

RESULTS

In the multivariable Cox analyses, the duration of AF, LAD, and persistent AF were independent risk factors for the recurrence of AF. The recurrence rate of AF 1 year after RFCA were significantly lower in groups A (odds ratio [OR], 0.160; 95% confidence interval [CI]: 0.073-0.352; P < 0.001) and C (OR, 0.388; 95% CI: 0.156-0.963; P = 0.041) than in the control group.

CONCLUSIONS

Reduction of LAD within 3 months after operation predicts the success rate of RFCA, with reduction within 1 month after operation having a higher success rate. This indicates the necessity of treatment in patients with AF who do not experience an early reduction in the LAD after RFCA.

Treatment-Related Changes in Left Atrial Structure in Atrial Fibrillation: Findings From the CABANA Imaging Substudy

[Figure: see text].