Predictors of late pulmonary vein reconnection in patients with arrhythmia recurrence after cryoballoon ablation-per vein analysis including cardiac computed tomography-based anatomic factors

Distance-dependent neuromodulation effect during thermal ablation for atrial fibrillation

INTRODUCTION

Thermal atrial fibrillation (AF) ablation exerts an additive treatment effect on the cardiac autonomic nervous system (CANS). This effect is mainly reported during ablation of the right superior pulmonary vein (RSPV), modulating the right anterior ganglionated plexus (RAGP), which contains parasympathetic innervation to the sinoatrial node in the epicardial fat pad between RSPV and superior vena cava (SVC). However, a variable response to neuromodulation after ablation is observed, with little to no effect in some patients. Our objective was to assess clinical and anatomic predictors of thermal ablation-induced CANS changes, as assessed via variations in heart rate (HR) postablation.

METHODS

Consecutive paroxysmal AF patients undergoing first-time PV isolation by the cryoballoon (CB) or radiofrequency balloon (RFB) within a 12-month time frame and with preprocedural cardiac computed tomography (CT), were evaluated. Preablation and 24-h postablation electrocardiograms in sinus rhythm were collected and analyzed to assess HR. Anatomic evaluation by CT included the measurement of the shortest distance between the SVC and RSPV ostium (RSPV-SVC distance).

RESULTS

A total of 97 patients (CB, n = 50 vs. RFB, n = 47) were included, with similar baseline characteristics between both groups. A significant HR increase postablation (ΔHR ≥ 15 bpm) occurred in a total of 37 patients (38.1%), without difference in number of patients between both thermal ablation technologies (CB, 19 [51%]), RFB, 18 [49%]). Independent predictors for increased HR were RSPV-SVC distance (odds ratio [OR]: 0.49, CI: 0.34-0.71, p value < .001), and age (OR: 0.94, CI: 0.89-0.98, p value = .003).

CONCLUSIONS

Thermal balloon-based PV isolation influences the CANS through its effect on the RAGP, especially in younger patients and patients with shorter RSPV-SVC distance.

Repeat catheter ablation for atrial fibrillation

Catheter ablation of atrial fibrillation (AF) is an established therapy that reduces AF burden, improves quality of life, and reduces the risks of cardiovascular outcomes. Although there are clear guidelines for the application of de novo catheter ablation, there is less evidence to guide recommendations for repeat catheter ablation in patients who experience recurrent AF. In this review, we examine the rationale for repeat ablation, mechanisms of recurrence, patient selection, optimal timing, and procedural strategies. We discuss additional important considerations, including treatment of comorbidities and risk factors, risk of complications, and effectiveness. Mechanisms of recurrent AF are often due to non-pulmonary vein (non-PV) triggers; however, there is insufficient evidence supporting the routine use of empiric lesion sets during repeat ablation. The emergence of pulsed field ablation may alter the safety and effectiveness of de novo and repeat ablation. Extrapolation of data from randomized trials of de novo ablation does not optimally inform efficacy in cases of redo ablation. Additional large, randomized controlled trials are needed to address important clinical questions regarding procedural strategies and timing of repeat ablation.

Pulmonary Vein Remodeling Between Atrial Fibrillation Subtypes: A Matched Comparison Cardiac Computed Tomography-Based Study Between Patients With Paroxysmal and Persistent Atrial Fibrillation

Although pulmonary vein (PV) isolation (PVI) is the cornerstone for atrial fibrillation (AF) ablation, no data exist comparing PV anatomy between AF subtypes directly. We aimed to compare PV anatomic characteristics between paroxysmal (PAF) and persistent AF (PeAF) in a matched population using cardiac computed tomography (CCT). Fifty-eight PeAF patients (with CCT prior first AF ablation procedure, absence of valvular disease/previous cardiac intervention), and 58 age-, sex-, body surface area-matched PAF patients were evaluated for left atrial (LA) and PV anatomy: ostial area, ovality index (OVI), transverse/frontal angles. In PeAF vs PAF group, beside higher LA volume index (LAVI), PVs' ostial areas were significantly larger (between 64 - 101 mm2, P < 0.001 for all PVs; remaining valid after LAVI adjustment for left superior [LS], left inferior [LI], and right inferior [RI]PV); left PVs were less oval (0.7 - 0.11 OVI decrease, P =0.039 for LSPV; P = 0.012 for LIPV); LSPV (P = 0.019), LIPV (P < 0.001), RIPV (P = 0.029) were more posteriorly directed; whereas LSPV (P = 0.002), and right superior PV (P = 0.043) were more superiorly directed. Incidence of anatomic variations or early branching was not different. This study showed significant anatomical PV differences between patients with PeAF and PAF, in terms of PV orientation, ostial size and ovality. Anticipating such anatomical differences may aid in choosing the adequate catheter design and technology for PeAF ablation.

Right superior pulmonary vein parameter determined by three-dimensional transesophageal echocardiography is an independent predictor of the outcome after cryoballoon isolation of the pulmonary veins

BACKGROUND

A direct comparison of three-dimensional transesophageal echocardiography (3DTEE) and cardiac computed tomography imaging has demonstrated good inter-technique agreement for the following pulmonary vein (PV) parameters: the ostium area of the right superior PV (RSPV) and its major (a) and minor axis (b) diameters, the left lateral ridge and the minor axis (b) diameter of the left superior PV. Herein, under investigation, was the predictive value of these parameters for arrhythmia recurrence (AR) after PV isolation with the 28 mm second generation cryoballoon (CBG2).

METHODS

One hundred eleven patients (67 men, mean age 58.06 ± 10.58 years) undergoing 3DTEE before PV isolation with the CBG2 for paroxysmal atrial fibrillation were followed. "Point by point" redo intervention was offered in case of AR and reconnected PVs were defined.

RESULTS

During a mean follow-up of 617 ± 258.86 days, 65 (58.9%) patients remained free of AR. Longer RSPV b was found to be the only significant predictor for AR (hazard ratio [HR] 1.059; 95% confidence interval [CI] 1.000-1.121; p = 0.048). RSPV b ≥ 28 mm resulted in a threefold (HR 3.010; 95% CI 1.270-7.134, p = 0.012) increase in the risk of AR. The association of RSPV b with AR was independent of the biophysical parameters of cryoapplications. In 25 "redo" patients, reconnections were found 1.75 times more likely in the RSPV than in the other 3 PVs altogether.

CONCLUSIONS

Right superior PV b measured with 3DTEE might be a significant predictor of AR after PV isolation with the CBG2. In case of RSPV b exceeding 28 mm, alternative PV isolation techniques or use of a larger balloon might be considered.

Comparison of pulmonary vein isolation using cryoballoon, high-power short-duration, and conventional radiofrequency ablation for atrial fibrillation: a propensity score-weighted study

Background

The comparative efficacy, saftey, and heart rate variability (HRV) parameters after pulmonary vein isolation using cryoballoon (Cryo-PVI), high-power short-duration (HPSD-PVI), and conventional radiofrequency ablation (conventional-PVI) for atrial fibrillation (AF) is unclear.

Materials and methods

In this propensity score-weighted, retrospective analysis of a single-center cohort, we analyzed 3,395 patients (26.2% female, 74.5% paroxysmal AF) who underwent AF catheter ablation without an empirical left atrial ablation. Procedural factors, recurrence rates, complication rates, and the post-procedural HRV parameters were compared across the Cryo-PVI (n = 625), HPSD-PVI (n = 748), and conventional-PVI (n = 2,022) groups.

Results

Despite the shortest procedural time in the Cryo-PVI group (74 min for Cryo-PVI vs. 104 min for HPSD-PVI vs. 153 min for conventional-PVI, p < 0.001), the major complication (p = 0.906) and clinical recurrence rates were similar across the three ablation groups (weighted log-rank, p = 0.824). However, the Cryo-PVI group was associated with a significantly lower risk of recurrent AF in patients with paroxysmal AF [weighted hazard ratio (WHR) 0.57, 95% confidence interval (CI) 0.37-0.86], whereas it was associated with a higher risk of recurrent AF in patients with persistent AF (WHR 1.41, 95% CI 1.06-1.89, p for interaction of <0.001) compared with the conventional-PVI group. In the subgroup analysis for the HRV, the Cryo-PVI group had the highest low-frequency-to-high-frequency ratio at 1-year post-procedure, whereas the HPSD-PVI group had the lowest low-frequency-to-high-frequency ratio at 1-year post-procedure (p < 0.001).

Conclusions

The Cryo-PVI group had better rhythm outcomes in patients with paroxysmal AF but worse rhythm outcomes in patients with persistent AF and a higher long-term post-procedural sympathetic nervous activity and sympatho-vagal balance compared with the conventional-PVI group.