Normal pulmonary veins anatomy is associated with better AF-free survival after cryoablation as compared to atypical anatomy with common left pulmonary vein

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 pulsed field ablation and cryoballoon ablation for pulmonary vein isolation

INTRODUCTION

Pulmonary vein isolation (PVI) remains the cornerstone in the treatment of atrial fibrillation (AF). PVI using cryoballoon (CB) technology has emerged as a standard procedure in many centers. Recently, pulsed field ablation (PFA) has been introduced and used to achieve PVI. First data show high acute and favorable long-term outcomes. So far, data comparing these new "single shot" devices are sparse. We sought to compare procedural and outcome data for first time PFA users versus CB in patients undergoing de novo PVI. Furthermore, potentially postprocedural discomfort and affection of autonomic ganglia were assessed.

METHODS AND RESULTS

A retrospective analysis and comparison of all de novo PVIs with PFA and CB was performed. Furthermore, PFA PVI learning curve was evaluated. During follow-up, repeat outpatient visits and Holter electrocardiogram were performed to analyze arrhythmia-free survival. Discomfort analysis was obtained by prescribed analgesic medication within first 48 h after PVI. Potential changes in heart rate (HR) between baseline and at 3-month follow-up were evaluated. A total of 108 patients (54 PFA and 54 CB; PFA; 33 (30%) female) with paroxysmal and persistent AF were analyzed. Type of AF was comparable (Patients suffering from PAF: PFA: 16 (30%), CB: 17 (31%), p = 1.0). In 107 (99%) patients, successful PVI was achieved. Transient phrenic palsy omitted complete PVI in one CB patient. A trend for a shorter overall procedure duration was observed in the PFA group (PFA: 64.5 ± 17.5 min; CB: 73.0 ± 24.8 min; p = 0.07). Excluding LA mapping time (first 14 cases), procedure time was significantly shorter using PFA (PFA: 58.0 ± 12.5 min, CB: 73.0 ± 24.8 min, p = 0.0001). Fluoroscopy time was significantly longer for PFA (PFA: 15.3 ± 4.7 min, CB: 12.3 ± 5.3 min; p = 0.001), but significantly less contrast medium was used (PFA: 12 ± 6 mL; CB: 51 ± 29 mL, p < 0.0001). Subgroup analysis of the PFA group revealed a significant shortening of procedure duration over time (first tertile: 72.7 ± 13.5 min, second tertile: 67.3 ± 21.7 min, third tertile: 53.4 ± 9.8 min, first vs. third tertile p < 0.0001). Two cardiac tamponades occurred in the PFA group (p = 0.495), of which one was most likely related to complex transseptal puncture. In the first 48 h after PVI, the number of prescribed analgesics due to postprocedural pain was equal between both groups (PFA: 7 (13%) patients, CB: 10 (19%) patients, p = 0.598). After a FU of 273 ± 129 days, 35 of 47 patients (74%) after PFA and 36 of 50 patients (72%) after CB PVI were free of any atrial arrhythmia (HR: 0.98, p = 0.88). Only in the PFA group, a significant increase in HR 3 months after PVI was observed (pre-PVI: 61 ± 8 beats/min, post-PVI: 65 ± 9 beats/min, p = 0.008).

CONCLUSION

The new PFA technology is equally effective and safe as compared to CB for complete PVI with potentially shorter procedure time and significantly less contrast medium. However, AF recurrence rates after PFA PVI seem to be comparable to CB PVI.

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

AIMS

To identify predictors of individual late pulmonary vein (PV) reconnection after second-generation cryoballoon (CB2) ablation. Anatomic indicators of late pulmonary vein reconnection (LPVR) post-CB2 ablation have not yet been studied on an individual PV level, nor weighed against clinical and procedural factors.

METHODS AND RESULTS

Clinical, procedural, and PV anatomic data from 125 patients with a repeat procedure for arrhythmia recurrence after index CB2 ablation were analyzed. Preprocedural computed tomography (CT) evaluated 486 PVs for measurement of size; shape (ovality index); carina width; and orientation angle in frontal (superior/inferior) and transversal (anterior/posterior) plane (with horizontal line 0° as reference and upper/lower half circle as positive/negative value, respectively). Durable isolation in all PVs was demonstrated in 50/125 (40%) patients. Late reconnection rates at the different PVs were as follows: 16% left superior (LS), 12% left inferior (LI), 17% right superior (RS), and 31% right inferior (RI) PV. Multivariable analysis performed per vein showed following independent determinants predicting LPVR: ovality index [odds ratio (OR) 1.61, 95% confidence interval (CI) 1.07-2.41, P = 0.022] and carina width (OR 0.75, CI 0.59-0.96, P = 0.024) for LSPV; carina width (OR 0.71, CI 0.53-0.95, P = 0.020) for LIPV; frontal angle (OR 0.91, CI 0.87-0.95, P < 0.001) for RIPV; and transversal angle (OR 1.15, CI 1.03-1.31, P = 0.032) for RSPV.

CONCLUSION

Cardiac CT-based evaluation of anatomic PV characteristics presented higher predictive value compared to clinical and procedural variables for individual LPVR after CB2 ablation. Pre-procedural identification of unfavourable PV anatomy might be important to tailor the ablation approach.

Impact of pulmonary veins anatomy on the outcomes of radiofrequency ablation for paroxysmal atrial fibrillation in the era of contact force-sensing ablation catheters

BACKGROUND

Pulmonary vein (PV) isolation (PVI) has become the cornerstone of atrial fibrillation (AF) ablation in patients with paroxysmal AF (PAF). PVI durability is influenced by many factors including PVs anatomy. Data regarding the influence of PVs anatomical variations on the outcomes of PAF ablation in the era of contact force-sensing ablation catheters are scarce and contradictory.

METHODS

Consecutive patients referred to our center for a first ablation of PAF using radiofrequency (RF) were included. PVs anatomy was classified into 3 groups: typical anatomy (4 distinct veins), left common ostium (LCO), and right accessory PV (RAPV). The primary outcome was recurrence of atrial arrhythmia episode during a 12-month follow-up after ablation.

RESULTS

Two hundred twenty-three patients were included (mean age 58.4 ± 10.8 years and 70.9% male). Among this cohort, 141 patients (63.2%) had typical PV anatomy, 53 (23.8%) had a LCO, and 29 (13.0%) had a RAPV. The existence of a RAPV was not associated with a higher rate of AF recurrences (22 (14.3%) vs. 7 (10.1%), p = 0.519). After multivariate analysis, the presence of an LCO did not appear to be associated with the AF recurrence rate at 12 months (OR = 1.69, 95%CI 0.95-2.49, p = 0.098). Maintenance of antiarrhythmic drugs after ablation was the only factor independently associated with a decreased risk of AF recurrence at 12 months (OR = 0.76, 95%CI 0.60-0.97, p = 0.046).

CONCLUSION

This study suggests that the presence of an LCO or a RAPV is not associated with a higher rate of AF recurrence at 12 months after radiofrequency PVI using contact force-sensing catheters in PAF patients.

Impact of pulmonary vein variant anatomy and cross-sectional orifice area on freedom from atrial fibrillation recurrence after cryothermal single-shot guided pulmonary vein isolation

BACKGROUND

Cryoballoon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). This study aimed to evaluate ablation efficacy and freedom from arrhythmia recurrence using the novel POLARx compared to the Arctic Front Advance Pro (AFA) CB system including the analysis of individual PV characteristics.

METHODS

A total of 687 patients underwent CB-guided ablation for AF. Arrhythmia recurrence was defined as an ECG documented episode of any AF/atrial tachycardia (AT) > 30 s. Anatomical characteristics were assessed using magnetic resonance imaging (MRI). For each PV, the cross-sectional orifice area (CSOA) was determined. Follow-up examinations were scheduled after 3, 6, and 12 months.

RESULTS

Acute PVI was achieved in all patients. Twelve-month AF-free survival was similar between the groups (POLARx 43/86 (50%) vs. AFA 318/601 (53%), Log-rank (LR) p = 0.346). MRI found a comparable percentage of patients with normal PV anatomy (POLARx 71/86 (83%) vs. AFA 530/601 (85%), p = 0.162). Patients with variant PV characteristics presented with a significantly impaired 12-month AF-free survival (normal PVs 326/585 (56%) vs. variant PVs 27/102 (27%), LR p < 0.001) independent of the applied CB ablation system. PAF patients with AF recurrence presented with significantly larger CSOA of the left-sided PVs and the right superior PVs (LSPV: p < 0.001; LIPV: p < 0.001; RSPV: p < 0.001). In PERS AF, no association between CSOA and ablation outcome was observed. Multivariate analyses identified PERS AF (hazard ratio (HR) 2.504, confidence interval (CI), 1.900-3.299, p < 0.001) and variant PV anatomy (HR 2.124, CI 1.608-2.805, p < 0.001) as independent predictors for AF recurrence.

CONCLUSIONS

Both CB ablation systems are associated with comparable 12-month AF-free survival rates. Variant PV anatomy seems to be predictive for AF recurrence. An association between CSOA and the outcome after CB-guided PVI was demonstrated for PAF.

Variations in human pulmonary vein ostia morphology: A systematic review with meta-analysis

This study aimed to establish the most accurate and up-to-date anatomical knowledge of pulmonary veins (PV), ostia variations, diameters and ostial area, to provide physicians, especially heart and thoracic surgeons with exact knowledge concerning this area. The main online medical databases, such as PubMed, Embase, Scopus, Web of Science, and Google Scholar, were searched to gather all studies in which the variations, maximal diameter, and ostial area of the PVs were investigated. During the study, the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed. Additionally, the critical appraisal tool for anatomical meta-analysis (CATAM) was used to provide the highest quality findings. The most common ostia variation is the classical one, which contains the left superior pulmonary vein (LSPV), left inferior pulmonary vein (LIPV), right superior pulmonary vein (RSPV) and right inferior pulmonary vein (RIPV). The mean diameter and ostial area of each pulmonary vein were established in the general population and in multiple variations considering the method of collecting the data and geographical location. Significant variability in PV ostia is observed. Left-sided PVs have smaller ostia than the corresponding right-sided PVs, and the inferior PVs ostia are smaller than the superior. The LCPV ostium size is the largest among all veins analyzed, while the RMPV ostium is the smallest. The results of this meta-analysis are hoped to help clinicians in planning and performing procedures that involve the pulmonary and cardiac areas, especially catheter ablation for atrial fibrillation.

Impact of the left common ostium following pulmonary vein isolation in AF : Systematic review and meta‐analysis

Purpose

Pulmonary vein isolation (PVI) through catheter ablation is the basis for the treatment of atrial fibrillation (AF). The left common ostium (LCO) is a high prevalence anatomical variation and has conflicting results in the effects on the prognosis following ablation. We undertook a systematic review and meta‐analysis of studies that compared the arrhythmia recurrence rate after radiofrequency ablation or cryoablation balloon between patients with normal pattern pulmonary vein and patients with LCO.

Methods and Results

Results were pooled using a fixed or random effect, at the discretion of heterogeneity (>25%), in addition, we associated subgroup analysis in these cases and when clinically indicated. Fourteen non‐randomized studies totaling 3278 patients were included. In analyses using the two energies all patients: OR 1.01 (95% CI 0.84–1.23; P = .90, I² = 67%) and excluding patients with any type of persistent AF (PeAF) and those submitted to linear atrial lesion (LAL) OR 0.80 (95% CI 0.52–1.22; P = .30, I² = 71%). Using CRYO: all patients OR 1.34 (95% CI 1.03–1.74; P = .03, I² = 0%). Using RF: all patients—OR 0.55 (95% CI 0.32–0.95; P = .03, I² = 49%); excluding studies with long duration PeAF and the performance of LAL concomitant—OR 0.45 (95% CI 0.23–0.91; P = .03, I² = 44%).

Conclusion

The results suggest a better prognosis in patients with LCO, submitted to PVI without additional LAL under RF energy in paroxysmal AF and short‐duration PeAF. In patients undergoing CRYO, the presence of LCO suggests a worse prognosis.

Unique Left Pulmonary Vein Isolation in Straight Common Trunk Based on Longitudinal Conduction of Left Lateral Ridge

BACKGROUND

A left common pulmonary vein (LCPV) is the most common anatomical variation in the pulmonary vein (PV) and often influences strategies of PV isolation for atrial fibrillation (AF). Our objective was to elucidate the electrical properties of the specific shape of LCPV and to apply it to an ablation procedure.

METHODS AND RESULTS

We investigated consecutive 12 out of 204 paroxysmal AF patients who had the shape of a straight common trunk in LCPV defined by the formation of a single conduit with parallel cranial and caudal walls after the coalescence of superior and inferior pulmonary veins on the distal side. The distance between the top of the bifurcation of LPVs and the level coinciding with the middle of the anterior wall of LCPV (left lateral ridge: LLR) was more than 10 mm in all the patients. The activation pattern of the LLR showed longitudinal conduction without outside connections. All the LCPV except one were successfully isolated without ablating the LLR (C-shape ablation). Only one patient had AF recurrence during the follow-up period.

CONCLUSION

The LLR in LCPV with a straight common trunk has longitudinal conduction without outside connections, which permits the isolation of LCPV without ablating LLR. This article is protected by copyright. All rights reserved.

The Long-Term Results of Three Catheter Ablation Methods in Patients With Paroxysmal Atrial Fibrillation: A 4-Year Follow-Up Study

Aims: Catheter ablation of paroxysmal atrial fibrillation (PAF) has been shown to be effective and safe. However, recurrence of PAF varies between 10 and 30% for radiofrequency ablation. There have been no reports comparing long-term recurrence rates following radiofrequency ablation, cryoablation, and three-dimensional guided cryoablation plus radiofrequency ablation. The aim of this study was to observe the long-term recurrence rate of PAF when treated by these three catheter ablation methods, and to explore clinical factors that can potentially predict PAF recurrence following catheter ablation. Methods: There were 238 patients involved in this study, including 106 radiofrequency (RF) ablation cases (RF group), 66 cryoablation cases (Freeze group), and 66 cases treated by three-dimensional guided cryoablation combined with radiofrequency ablation (Freeze-plus-RF group). All patients underwent standardized follow-up. The recurrence rate of atrial fibrillation (AF) in the three groups was calculated. Predictive factors for the recurrence of AF were also investigated. Results: At 48 months (the median follow-up period), the sinus rhythm maintenance rate was 77.4% in the RF group, 72.7% in the Freeze group, and 81.8% in the Freeze-plus-RF group. The maintenance rate of sinus rhythm was highest in the Freeze-plus-RF group, but differences among the three groups were not statistically significant. Further analysis found that the preoperative left atrial appendage emptying velocity (LAAEV) (recurrence vs. no recurrence, 56.58 ± 18.37 vs. 65.59 ± 18.83, respectively, p = 0.003), left atrial (LA) anteroposterior dimension (recurrence vs. no recurrence, 36.56 ± 4.65 vs. 35.00 ± 4.37, respectively; p = 0.028), and LA vertical dimension (recurrence vs. no recurrence, 56.31 ± 6.96 vs. 53.72 ± 6.52, respectively; p = 0.035) were related to postoperative recurrence. Multiple Cox regression analysis showed that only LAAEV was predictive of postoperative recurrence of PAF (hazard ratio: 0.979; 95% confidence interval: 0.961-0.997). Conclusion: Our study found that there was no statistically significant difference in long-term recurrence rates among the RF, Freeze, and Freeze-plus-RF groups. Preoperative LAAEV is an independent predictor of postoperative recurrence of PAF.

Comparison of atrial fibrillation ablation using cryoballoon versus radiofrequency in patients with left common pulmonary veins: mid-term follow-up results

PURPOSE

Cryoballoon (CB) and radiofrequency (RF) ablation techniques have similar outcomes for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). However, there is limited data about the impact of different ablation strategies in patients with left common pulmonary vein (LCPV). Our aim was to compare the safety and efficacy of RF and CB ablation in AF patients with LCPV.

METHODS

One hundred and twenty-seven (n = 80 CB and n = 47 RF) AF patients with LCPV detected by preprocedural computerized tomography (CT) were included in the study. Ostial dimensions and trunk distance were measured in all patients. Atrial tachyarrhythmia (ATa) recurrence was defined as detection of AF, atrial flutter, or atrial tachycardia (≥ 30 s) after a 3-month blanking period.

RESULTS

There was no significant difference in acute procedural success rates for PVI (97.5% in CB and 97.9% in RF, respectively, P = 0.953) and complication rates were similar between the groups (6 (7.5%) in CB and 4 (8.5%) in RF, respectively, P = 1.000). During a median follow-up of 20.7 (4.8-50.2) months for CB and 20.5 (6.2-36.0) months for RF, ATa recurrence was 35.0% and 38.2%, respectively (P = 0.777). Multivariate analysis did not reveal any of the morphologic parameters of LCPV as a significant predictor of ATa recurrence.

CONCLUSIONS

Our findings demonstrated that both CB and RF ablation techniques have similar efficacy and safety in AF patients with LCPV during the mid-term follow-up.

Anatomic characteristics of the left atrium in subjects undergoing radiofrequency ablation for atrial fibrillation

OBJECTIVE

To analyze the anatomic characteristics of the left atrium and pulmonary veins in individuals undergoing ablation for atrial fibrillation and to identify possible anatomic factors related with recurrence.

MATERIAL AND METHODS

We retrospectively reviewed the CT angiography studies done to plan radiofrequency ablation for atrial fibrillation in 95 patients (57 men; mean age, 65 ± 10 y). We reviewed the anatomy of the pulmonary veins and recorded the diameters of their ostia as well as the diameter and volume of the left atrium. We analyzed these parameters according to the type of arrhythmia and the response to treatment.

RESULTS

In 71 (74.7%) patients, the anatomy of the pulmonary veins was normal (i.e., two right pulmonary veins and two left pulmonary veins). Compared to patients with paroxysmal atrial fibrillation, patients with persistent atrial fibrillation had slightly larger diameter of the left pulmonary veins (left superior pulmonary vein 17.9 ± 2.6 mm vs. 16.7 ± 2.2 mm, p = 0.04; left inferior pulmonary vein 15.3 ± 2 mm vs. 13.8 ± 2.2 mm, p = 0.009) and larger left atrial volume (91.9 ± 24.9 cm³ vs. 70.7 ± 20.3 mm³, p = 0.001). After 22.1 ± 12.1 months' mean follow-up, 41 patients had sinus rhythm. Compared to patients in whom the sinus rhythm was restored, patients with recurrence had greater left atrial volume (81.4 ± 23.0 mm³ vs. 71.1 ± 23.2 mm³, p = 0.03). No significant differences in pulmonary vein diameters or clinical parameters were observed between patients with recurrence and those without.

CONCLUSION

The volume of the left atrium is greater in patients with persistent atrial fibrillation and in those who do not respond to ablation.

Safety and Efficacy Using the Second-Generation Cryoballoon in Patients With Atrial Fibrillation and a Common Ostium of Inferior Pulmonary Veins

Background: Common ostium of inferior pulmonary veins (COIPV) is a kind of pulmonary vein variation. The safety and efficacy of COIPV isolation using the second-generation cryoballoon (CB) ablation remain unknown.

Methods: A total of 10 patients with COIPV from a consecutive series of 1,751 patients with atrial fibrillation (AF) were included. Pulmonary vein isolation (PVI) was performed using the second-generation CB.

Results: The prevalence of a COIPV was 0.57% in this study. PVI was achieved in all pulmonary veins (PVs) without the need for a touch-up. A segmental freeze strategy was applied for each inferior PV, respectively. The mean number of freeze cycles of inferior PVs was 1.4 ± 0.5 for the left inferior pulmonary vein (LIPV), and 2.0 ± 0.9 for the right inferior pulmonary vein (RIPV). Pulmonary vein potential (PVP) of RIPV could not be monitored in real-time in three cases. Eight of 10 patients (80%) were free from atrial arrhythmias without the use of antiarrhythmic drugs during a follow-up period of 23.6 ± 12.9 months. No procedure-related complications occurred in any of the 10 patients.

Conclusions: Common ostium of inferior pulmonary veins is a rare but challenging PV variant. PVI with this unusual anatomic variation using the second-generation 28-mm CB is effective and safe.

Orientation of the right superior pulmonary vein affects outcome after pulmonary vein isolation

AIMS

Controversial results have been published regarding the influence of pulmonary vein (PV) anatomical variations on outcomes after pulmonary vein isolation (PVI). However, no data are available on the impact of PV orientation on the long-term success rates of point-by-point PVI. We sought to determine the impact of PV anatomy and orientation on atrial fibrillation (AF)-free survival in patients undergoing PVI using the radiofrequency point-by-point technique.

METHODS AND RESULTS

We retrospectively included 448 patients who underwent initial point-by-point radiofrequency ablation for AF at our department. Left atrial computed tomography angiography was performed before each procedure. PV anatomical variations, ostial parameters (area, effective diameter, and eccentricity), orientation, and their associations with 24-month AF-free survival were analysed. PV anatomical variations and ostial parameters were not predictive for AF-free survival (all P > 0.05). Univariate analysis showed that female sex (P = 0.025) was associated with higher rates of AF recurrence, ventral-caudal (P = 0.002), dorsal-cranial (P = 0.034), and dorsal-caudal (P = 0.042) orientation of the right superior PV (RSPV), on the other hand, showed an association with lower rates of AF recurrence, when compared with the reference ventral-cranial orientation. On multivariate analysis, both female sex [odds ratio (OR) 1.83, 95% CI 1.15-2.93, P = 0.011] and ventral-caudal RSPV orientation, compared with ventral-cranial orientation, proved to be independent predictors of 24-month AF recurrence (OR 0.37, 95% CI 0.19-0.71, P = 0.003).

CONCLUSION

Female sex and ventral-caudal RSPV orientation have an impact on long-term arrhythmia-free survival. Assessment of PV orientation may be a useful tool in predicting AF-free survival and may contribute to a more personalized management of AF.

Clinical Applications of Laser Technology: Laser Balloon Ablation in the Management of Atrial Fibrillation

Catheter-based ablation techniques have a well-established role in atrial fibrillation (AF) management. The prevalence and impact of AF is increasing globally, thus mandating an emphasis on improving ablation techniques through innovation. One key area of ongoing evolution in this field is the use of laser energy to perform pulmonary vein isolation during AF catheter ablation. While laser use is not as widespread as other ablation techniques, such as radiofrequency ablation and cryoballoon ablation, advancements in product design and procedural protocols have demonstrated laser balloon ablation to be equally safe and effective compared to these other modalities. Additionally, strategies to improve procedural efficiency and decrease radiation exposure through low fluoroscopy protocols make this technology an increasingly promising and exciting option.

Association of the left common ostium with clinical outcome after pulmonary vein isolation in atrial fibrillation

Introduction

Electrical pulmonary vein isolation (PVI) is used for the invasive treatment of atrial fibrillation (AF). However, despite the procedure’s technical evolution, the rate of AF recurrence due to electrical reconnection of the PVs is high. The aims of this study was to assess the influence of left common pulmonary venous ostium (LCO) on clinical outcomes following PVI.

Methods

Retrospective cohort of 254 patients who underwent the first procedure of PVI from the years 2013–2018 was assessed. Patients with persistent AF of long duration and extra-pulmonary focus associated with triggers for arrhythmia were excluded. Patients were stratified into two groups according to the presence of a LCO and received follow up for atrial tachyarrhythmia-free survival. The mean follow-up period was 28 ± 1.73 months.

Results

The majority were men (68.5%), with a mean age of 54 ± 12 years. With respect to the atrial anatomy, LCO occurred in 23.6% of cases after pulmonary venous angiotomography. The arrhythmia-free survival rate was 79.5% in the follow-up period. The Cox regression model was utilized and the adjusted hazard ratio for LCO was 0.36 (95% CI 0.15–0.87; p = 0.02) in terms of age, body mass index, left atrium diameter, bi-directional blocking of the cavotricuspid isthmus, persistent AF, left ventricular ejection fraction adjusted model.

Conclusion

Anatomic abnormality with the presence of the LCO is present in a quarter of patients undergoing AF ablation, which is associated with a lower rate of arrhythmia recurrence in our population.

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Pulmonary vein isolation is used for the invasive treatment of atrial fibrillation.

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The majority of arrhythmias triggers have their origins in the anatomic abnormality.

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Pulmonary vein isolation using radiofrequency ablation.

Presence of a left common pulmonary vein and pulmonary vein anatomical characteristics as predictors of outcome following cryoballoon ablation for paroxysmal atrial fibrillation

PURPOSE

Pulmonary vein (PV) isolation using cryoballoon ablation (CBA) is a common therapy for patients with drug-refractory paroxysmal atrial fibrillation (PAF). However, initial CBA is successful in only 70-80% of patients. The role of an atypical left common PV (LCPV) and PV anatomical indices on CBA outcomes remains unclear.

METHODS

We followed 80 patients (age 60.7 ± 9.7, 31 % women) with PAF undergoing CBA for 1-year post-procedure for the development of recurrent atrial arrhythmias (AA). Recurrence was assessed by documented AA on EKG or any form of long-term cardiac rhythm monitoring. The presence of an LCPV and individual PV diameters were evaluated using cardiac CT. Based on the maximum and minimum PV ostial diameters, the eccentricity index (EI), ovality index (OI), and PV ostial area (PVA) were calculated for all the veins. A multivariable Cox-proportional hazard model assessed whether the presence of an LCPV or PV anatomic indices (EI, OI, and PVA) predicted recurrence of AA following CBA.

RESULTS

After 1-year follow-up, 19 (23.7%) participants developed recurrence of AA. On multivariable regression, the presence of an LCPV did not predict the recurrence of AA (p = 0.38). Among the PV anatomical indices, on univariate analysis, only the area of the left inferior PV showed a trend towards predicting recurrence, though this result was not significant on multivariate analysis (p = 0.09).

CONCLUSIONS

In patients with PAF, neither the presence of an LCPV nor individual PV anatomical indices predicted recurrence of AA following CBA.

Cryoballoon ablation of atrial fibrillation in patients with atypical right pulmonary vein anatomy

BACKGROUND

Cryoballoon ablation is widely used for pulmonary vein isolation in patients with atrial fibrillation. There are no data regarding the clinical efficacy of cryoballoon ablation in patients with atypical right pulmonary vein anatomy.

AIM

We aimed to evaluate the impact of right pulmonary vein anatomy on the safety and efficacy of cryoballoon ablation.

METHODS

Patients referred for cryoballoon ablation of paroxysmal atrial fibrillation were enrolled prospectively. Left atrial computed tomography was performed before cryoballoon ablation to determine whether the right pulmonary vein anatomy was "normal" or "atypical". For patients with atypical anatomy, cryoballoon ablation was only performed for right superior and right inferior pulmonary veins, neglecting accessory pulmonary veins.

RESULTS

Overall, 303 patients were included: 254 (83.8%) with normal and 49 (16.2%) with atypical right pulmonary vein anatomy. First-freeze isolation for right superior and right inferior pulmonary veins occurred in 44 (89.8%) and 37 (75.5%) patients with atypical pulmonary vein anatomy, and in 218 (85.8%) and 217 (85.4%) patients with typical pulmonary vein anatomy, respectively (P not significant). Phrenic nerve palsies were only observed in patients with normal anatomy (0 vs. 26 [8.6%]; P=0.039). Mid-term survival free from atrial arrhythmia was similar, regardless of right pulmonary vein anatomy.

CONCLUSIONS

A significant proportion of patients have atypical right pulmonary vein anatomy. Procedural characteristics, acute pulmonary vein isolation success and mid-term procedural efficacy were similar, regardless of right pulmonary vein anatomy. In addition to left-side pulmonary vein isolation, cryoballoon ablation of right superior and right inferior pulmonary veins only, neglecting accessory pulmonary veins, is sufficient to obtain acute right-side pulmonary vein isolation and mid-term sinus rhythm maintenance in patients with atypical anatomy.

The impact of left common pulmonary vein on cryoballoon ablation of atrial fibrillation. A meta-analysis

Introduction

Conflicting results regarding the impact of left common pulmonary vein (LCPV) on clinical outcome of atrial fibrillation (AF) ablation with cryoballoon technology have been reported.

Methods

We systematically searched PubMed and Cochrane library for articles that compared the arrhythmia recurrence rate after cryoballoon ablation between patients with normal pattern PVs and patients with LCPV. Studies of first ablation for persistent and paroxysmal AF using the 28 mm Arctic Front Advance, Medtronic cryoballoon (CB-A) reporting clinical success rates at a mean follow-up of ≥12 months were included. Data were analyzed by applying a random effects model.

Results

A total of 5 studies with a total of 1178 patients met our predefined inclusion criteria. After a mean follow-up of 18.4 months, the overall success rate of CB-A ablation among patients with persistent and paroxysmal AF was 57%; in the LCPV group the success rate was 46% and in the normal anatomical pattern group it was 61%. No significant heterogeneity was noted among the studies (I² = 35.8%; Q (df = 3) = 6.23 p-value = 0.18). Arrhythmia recurrence after CB-A ablation was not statistically significant between the two groups (LogOR 0.24; 95% CI [-0.16-0.63]; p-value = 0.23). No significant difference in PNI was observed between the two groups (p-value = 0.693).

Conclusion

The presence of LCPV does not affect the long-term outcome of paroxysmal and persistent atrial fibrillation ablation with 28 mm CB-A compared to normal left PVs pattern.

Impact of Left Common Pulmonary Veins in the Contact-Force vs. Cryoballoon Atrial Fibrillation Ablation (CIRCA-DOSE) Study

BACKGROUND

Concerns remain regarding the effectiveness of PVI using the fixed diameter non-compliant cryoballoon in the presence of a left common pulmonary vein (LCPV). We sought to evaluate the effectiveness of PVI performed by contact-force guided radiofrequency (CF-RF) versus second-generation cryoballoon-based ablation in patients with LCPV.

METHODS AND RESULTS

We enrolled 346 patients with paroxysmal AF and randomized them to CF-RF or cryoballoon ablation. PV anatomy was not assessed prior to enrolment, and there were no exclusions based on PV anatomy. All patients received an implantable cardiac monitor. LCPV was observed in 13.6% of patients (47/346). Left atrial time and fluoroscopy time did not differ between those with and without LCPV (P=0.58 and P=0.06, respectively). Freedom from any atrial tachyarrhythmia at one year was observed in 46.8% with LCPV and 54.5% without LCPV (P=0.06). In those with LCPV the freedom from any atrial tachyarrhythmia did not differ between those randomized to CF-RF or cryoballoon ablation (HR for recurrence 1.19, 95% CI 0.53-2.65, P=0.69). In those with LCPV the AF burden was reduced to a similar extent with CF-RF and cryoballoon ablation (99.7% vs. 99.5%, respectively; P=0.97).

CONCLUSIONS

In this randomized clinical trial, the presence of a LCPV was associated with a trend towards higher rates of arrhythmia recurrence following PVI. No significant difference in arrhythmia recurrence was observed between patients with LCPV randomized to cryoballoon ablation or contact-force guided RF ablation, suggesting that either ablation modality is suitable in this population. (Cryoballoon vs. Irrigated Radiofrequency Catheter Ablation [CIRCA-DOSE], NCT01913522) This article is protected by copyright. All rights reserved.

Anatomic predictors of recurrence after cryoablation for atrial fibrillation: a computed tomography based composite score

BACKGROUND

Effective pulmonary vein isolation (PVI) with cryoablation depends on adequate occlusion of pulmonary veins (PV) by the cryoballoon and is therefore likely to be affected by PV and left atrial (LA) anatomical characteristics and variants. Thus, the objective of this study was to investigate the effect of LA and PV anatomy, evaluated by computed tomography (CT), on acute and long-term outcomes of cryoablation for atrial fibrillation (AF).

METHODS

Fifty-eight patients (64.72 + 9.44 years, 60.3% male) undergoing cryoablation for paroxysmal or early persistent AF were included. Pre-procedural CT images were analyzed to evaluate LA dimensions and PV anatomical characteristics. Predictors of recurrence were identified using regression analysis.

RESULTS

60.3% of patients had two PVs on each side with separate ostia, whereas 29.3% and 10.3% had right middle and left common PVs, respectively. The following anatomic characteristics were found to be independent predictors of recurrence: right superior PV ostial max:min diameter ratio > 1.32, left superior PV ostial max:min diameter ratio > 1.2, right superior PV antral circumference > 69.1 mm, right inferior PV antral circumference > 61.38 mm, right superior PV angle > 22.7°. Using these factors, LA diameter and right middle PV, a scoring model was created for prediction of "unfavorable" LA-PV anatomy (AUC = 0.867, p = 0.000009, score range = 0-7). Score of ≥ 4 predicted need for longer cryoenergy ablation (p = 0.039) and more frequent switch to radiofrequency energy (p = 0.066) to achieve PVI, and had a sensitivity of 83.3% and specificity of 82.5% to predict clinical recurrence.

CONCLUSION

CT-based scoring system is useful to identify "unfavorable" anatomy prior to cryo-PVI, which can result in procedural difficulty and poor outcomes.

The Impact of Pulmonary Vein Anatomy on the Outcomes of Catheter Ablation for Atrial Fibrillation

Background and Objectives: Prior studies have identified a number of predictors for Atrial fibrillation (AF) ablation success, including comorbidities, the type of AF, and left atrial (LA) size. Ectopic foci in the initiation of paroxysmal AF are frequently found in pulmonary veins. Our aim was to assess how pulmonary vein anatomy influences the recurrence of atrial fibrillation after radiofrequency catheter ablation. Materials and Methods: Eighty patients diagnosed with paroxysmal or persistent AF underwent radiofrequency catheter ablation (RFCA) between November 2016 and December 2017. All of these patients underwent computed tomography before AF ablation. PV anatomy was classified according to the presence of common PVs or accessory PVs. Several clinical and imagistic parameters were recorded. After hospital discharge, all patients were scheduled for check-up in an outpatient clinic at 3, 6, 9, and 12 months after RFCA to detect AF recurrence. Results: A total of 80 consecutive patients, aged 53.8 ± 9.6 years, 54 (67.5%) men and 26 (32.5%) women were enrolled. The majority of patients had paroxysmal AF 53 (66.3%). Regular PV anatomy (2 left PVs, 2 right PVs) was identified in 59 patients (73.7%), a left common trunk (LCT) was detected in 15 patients (18.7%), an accessory right middle pulmonary vein (RMPV) was found in 5 patients (6.25%) and one patient presented both an LCT and an RMPV. The median follow-up duration was 14 (12; 15) months. Sinus rhythm was maintained in 50 (62.5%) patients. Age, gender, antiarrhythmic drugs, and the presence of cardiac comorbidities were not predictive of AF recurrence. The diagnosis of persistent AF before RFCA was more closely associated with an increase in recurrent AF after RFCA than after paroxysmal AF (p = 0.01). Longer procedure times (>265 minutes) were associated with AF recurrence (p = 0.04). Patients with an LA volume index of over 48.5 (mL/m²) were more likely to present AF recurrence (p = 0.006). Multivariate analysis of recurrence risk showed that only the larger LA volume index and variant PV anatomy were independently associated with AF recurrence. Conclusion: The study demonstrated that an increased volume of the left atrium was the most important predictive factor for the risk of AF recurrence after catheter ablation. Variant anatomy of PV was the only other independent predictive factor associated with a higher rate of AF recurrence.

Incidence of early pulmonary vein reconnections using different energy sources for pulmonary vein isolation: Multielectrode phased radiofrequency vs second-generation cryoballoon

OBJECTIVE

To determine and compare the incidence of early recurrence of conduction after pulmonary vein isolation (PVI) using two different ablation technologies: phased radiofrequency by a multipolar ablation catheter (PVAC) and cryo-ablation by a second-generation cryoballoon (CB).

METHODS AND RESULTS

Two hundred patients (pts) with atrial fibrillation underwent PVI with PVAC (Group 1) or CB (Group 2), with 100 pts in each group. The incidence of PV reconnection (PVR) for each vein was examined in both groups at least 30 minutes after successful PVI. There were no significant clinical differences between both groups. Total procedure-, fluoroscopy-, and left atrial (LA) dwell time were significantly shorter in Group 2 pts (P < .0001). Early PVR was recorded in 69/388 (18%) isolated PVs or left common trunks (CTs) in Group 1 compared with 25/386 (7%) in Group 2 (P < .0001). Forty-three pts in Group1 were found to have PVR compared with 22 pts in Group 2 (P = .0015). Group 1 pts with CTs showed significantly more PVR than pts of Group 2 (P = .047). In both groups, CTs and CT branches were found to reconnect significantly more frequent compared with all other veins.

CONCLUSION

Both PVAC and CB are effective to achieve PVI. Early PVR is observed with the significantly lower frequency with second-generation CB compared with PVAC, contributing to shorter procedure-, fluoroscopy, and LA dwell times. CTs and CT branches exhibit the highest incidence of PVR for both devices.

Common pulmonary vein on the recurrence of atrial tachyarrhythmia after pulmonary vein isolation

AIMS

Catheter ablation has become an effective treatment modality for atrial fibrillation (AF). However, the relationship between common pulmonary vein (PV) and recurrent atrial tachyarrhythmia (ATA) after PV isolation (PVI) remains controversial. This study aimed to explore the function of common PV on the risk of recurrent ATA after PVI.

METHODS

We identified a total of 191 patients who received radiofrequency catheter ablation for paroxysmal AF at our hospital between July 2010 and December 2017 for retrospective chart review. We collected the following data for analysis: results of preprocedural computed tomography, including the anatomy of PV and left atrial (LA) volume; the incidence of early- and late-onset recurrence of ATA. We compared these characteristics between the two groups defined by the presence or absence of the late-onset recurrence of ATA.

RESULTS

Compared to the no ATA recurrence group, the ATA recurrence group had larger LA size, larger LA end-diastolic and systolic volumes, larger maximal diameter of PV, higher prevalence of common PV, and higher incidence of early-onset recurrence of ATA. In multivariate logistic regression analyses, presence of common PV and early-onset recurrence were independently associated with late-onset recurrence of ATA. Compared to patients without common PV, patients with common PV had larger diameter of PV and higher incidence of late-onset recurrent ATA.

CONCLUSION

In patients with paroxysmal AF, early-onset recurrence of ATA and the presence of common PV were independently associated with late-onset recurrent ATA after radiofrequency catheter ablation.

Long-term outcomes of cryoballoon pulmonary vein isolation for paroxysmal and persistent atrial fibrillation in Chinese patients

PURPOSE

We aimed to study the long-term outcomes of cryoballoon (CB) pulmonary vein isolation (PVI) in treating Chinese patients with atrial fibrillation (AF).

METHODS

A total of 122 patients (48 women, mean age 57.4 ± 11.3) underwent CB PVI (first generation CB 44.3%, second generation CB 55.7%) for AF (paroxysmal 65.6%, persistent 10.7% and long-standing persistent 23.8%).

RESULTS

PVI was achieved in 113 (92.6%) patients with CB alone, and it was achieved in all patients with additional touch-up by 8-mm-tip cryocatheter. The mean procedural and fluoroscopic duration were 171.9 ± 41 and 46.6 ± 14.6 min respectively. The recurrence-free survival for paroxysmal and non-paroxysmal AF was 77% and 59% respectively at 1 year and progressively declined over time to reach a plateau of 52% and 30% for paroxysmal and non-paroxysmal AF respectively at 5 years. In patients undergoing PVI with second-generation CB, the recurrence-free survival was 75% for paroxysmal AF and 45% for non-paroxysmal AF at 5 years. With multivariate Cox regression analysis, the types of CB (use of second-generation CB: HR 0.49; 95% CI 0.28-0.85; p = 0.011) and size of left atrium (LA) (larger LA size: HR 1.52; 95% CI 1-2.14; p = 0.017) independently predicted recurrence. Transient phrenic nerve injury (PNI) occurred in four (3.3%) patients and persistent PNI occurred in four (3.3%) patients. Other complications occurred in 10 (8.2%) patients with no procedure-related death.

CONCLUSIONS

Long-term success of CB PVI for AF declined over time and reached a plateau at 5 years. CB types and LA size are independent predictors for long-term recurrence.

Pulmonary vein anatomy variants as a biomarker of atrial fibrillation - CT angiography evaluation

Background

It has been suggested that changes in pulmonary veins (PV) and left atrium (LA) anatomy may have an influence on initiating atrial fibrillation (AF) and the effectiveness of pulmonary vein isolation (PVI) in patients (pts) with atrial fibrillation.

The aim of the study was to assess anatomy abnormalities of the PV and LA in the patients with the history of AF and compare it with the control group(CG).

Methods

The multi-slice tomography (MSCT) scans were performed in 224 AF pts. before PVI (129 males, mean age 59 ± 9 yrs). The CG consisted of 40 pts. without AF (26 males, age 45 ± 9 yrs). LA and PV anatomy were evaluated. Diameters of PV ostia were measured in two directions: anterior-posterior (AP) and superior-inferior (SI) automatically using Vitrea 4.0.

Results

Pulmonary veins anatomy variants were observed more frequently in the atrial fibrillation group - 83 pts. (37%) vs 6 pts. (15%) in CG; 9% (21 pts) left common ostia (CO), 2% (5 pts) right CO, 19% (42 pts) additional right PV (APV), (1.8%) 4 pts. APV left, 8% right early branching (EB) and 3.5% left EB. The LA diameter differed significantly in AF vs CG group (41.2 ± 6 mm vs 35 ± 4.2 mm, p < 0.0001) respectively.

Conclusions

The anomalies of pulmonary vein anatomy occurred more often in pts. with AF. They can be defined as an image biomarkers of atrial fibrillation. Right additional (middle) pulmonary vein was the most important anomaly detected in AF patients as well as enlargered diameters of the LA and PV ostia.

Pulmonary Vein Anatomy is Associated with Cryo Kinetics during Cryoballoon Ablation for Atrial Fibrillation

Background

The influence of pulmonary vein (PV) anatomy on cryo kinetics during cryoballoon (CB) ablation is unclear.

Objective

To investigate the relationship between PV anatomy and cryo kinetics during CB ablation for atrial fibrillation (AF).

Methods

Sixty consecutive patients were enrolled. PV anatomy, including ostial diameters (long, short and corrected), ratio between short and long diameters, ostium shape (round, oval, triangular, and narrow), and drainage pattern (typical, with common trunk, common antrum, ostial branch and supernumerary PV) were evaluated on multi-detector computed tomography (MDCT) images pre-procedure. Cryo kinetics parameters [balloon freeze time from 0 to -30ºC (BFT), balloon nadir temperature (BNT) and balloon warming time from -30 to +15ºC (BWT)] were recorded during procedure. All p values are two-sided, with values of p < 0.05 considered to be statistically significant.

Results

606 times of freezing cycle were accomplished. Moderate negative correlation was documented between BNT and corrected PV diameter (r = -0.51, p < 0.001) when using 23-mm CBs, and mild negative correlation (r = - 0.32, p = 0.001) was found when using 28-mm CBs. Multivariate logistic regression analysis revealed that PV corrected ostial diameter (OR, 1.4; p = 0.004) predicted a BNT < -51ºC when using 23-mm CBs, while PV ostium oval shape (OR, 0.3; p = 0.033) and PV locations (left inferior PV: OR, 0.04; p = 0.005; right superior PV: OR, 4.3; p = 0.025) predicted BNT < -51ºC when using 28-mm CBs.

Conclusions

MDCT can provide PV anatomy accurate evaluation prior CB ablation. PV anatomy is associated with cryo kinetics during ablation.

Atrial fibrillation ablation using cryoballoon technology: Recent advances and practical techniques

Atrial fibrillation (AF) affects 1-2% of the population, and its prevalence is estimated to double in the next 50 years as the population ages. AF results in impaired patients' life quality, deteriorated cardiac function, and even increased mortality. Antiarrhythmic drugs frequently fail to restore sinus rhythm. Catheter ablation is a valuable treatment approach for AF, even as a first-line therapy strategy in selected patients. Effective electrical pulmonary vein isolation (PVI) is the cornerstone of all AF ablation strategies. Use of radiofrequency (RF) catheter in combination of a three-dimensional electroanatomical mapping system is the most established ablation approach. However, catheter ablation of AF is challenging even sometimes for experienced operators. To facilitate catheter ablation of AF without compromising the durability of the pulmonary vein isolation, "single shot" ablation devices have been developed; of them, cryoballoon ablation, is by far the most widely investigated. In this report, we review the current knowledge of AF and discuss the recent evidence in catheter ablation of AF, particularly cryoballoon ablation. Moreover, we review relevant data from the literature as well as our own experience and summarize the key procedural practical techniques in PVI using cryoballoon technology, aiming to shorten the learning curve of the ablation technique and to contribute further to reduction of the disease burden.

Impact of left atrial size on isolation area in the acute phase of pulmonary vein isolation using 28 mm cryoballoon

BACKGROUND

The impact of left atrial (LA) size on isolation area (ISA) using a 28-mm second-generation cryoballoon (CB) in the acute phase after pulmonary vein isolation (PVI) and the differences of CB from contact force-guided radiofrequency (RF) ablation have not been fully investigated.

METHODS

We examined 85 consecutive patients (CB group, 35; RF group, 50) with drug-refractory paroxysmal atrial fibrillation who underwent their first PVI procedure at two institutions. We evaluated ISA after PVI using 3D-Merge computed tomography images (GE Healthcare, Little Chalfont, UK) and high-resolution electroanatomical mapping.

RESULTS

Total ISA was significantly smaller in the CB group (20.6 ± 6.0 cm² ) than in the RF group (29.0 ± 7.1 cm² ; P < 0.0001). In the CB group, ISA of the left pulmonary vein (LPV), right pulmonary vein (RPV), and total ISA were not correlated with the left atrial surface area (LASA). The ratios of ISA to LASA (%ISA) of LPV and total ISA negatively correlated with LASA in the CB group (LPV: r = -0.4001, P = 0.0173; total ISA: r = -0.4733, P = 0.0041). In contrast, in the RF group, ISA of LPV, RPV, and total ISA positively correlated with LASA; (LPV: r = 0.5155, P = 0.001; RPV: r = 0.6398, P < 0.0001; total ISA: r = 0.7299, P < 0.0001).

CONCLUSION

ISA created using CB was significantly smaller than that using RF and did not change regardless of LASA increment. Differences in ISA between the two groups became more prominent in the large atrium.

Cryoballoon Ablation in Today's Practice: Can the Left Common Ostium Be Ablated and Injury to the Right Phrenic Nerve Avoided?

Cryoballoon ablation is rapidly gaining popularity among electrophysiologists in the setting of pulmonary vein isolation for the treatment of AF. The first part of the following review focuses on the feasibility and clinical outcome of this technique in patients exhibiting a left common ostium. In the second part, we discuss how to predict and prevent the most common complication related to cryoballoon ablation: right phrenic nerve palsy.

Cryoballoon ablation in atrial fibrillation: Advantages and drawbacks

Pulmonary vein isolation is the cornerstone of atrial fibrillation ablation and is effective for preventing arrhythmias recurrences, especially in patients with paroxysmal atrial fibrillation. During the last years, cryoballoon ablation has emerged as an unquestionable alternative approach to radiofrequency ablation. Many non-randomized and randomized trials have proven undoubtedly that cryoballoon ablation displays similar efficacy and overall safety profile, when compared to radiofrequency ablation for the treatment of patients with drug-refractory paroxysmal atrial fibrillation. These results have been obtained in all types of pulmonary veins anatomical subsets, which confirms that there is no need to select patients according to the latter. The value of cryoablation in the setting of short persistent atrial fibrillation still needs more evidence. Importantly, cryoballoon ablation seems to be less operator-dependent and more reproducible than radiofrequency for the isolation of pulmonary veins.

Effect of left atrial volume and pulmonary vein anatomy on outcome of nMARQ™ catheter ablation of paroxysmal atrial fibrillation

PURPOSE

Left atrial volume (LA) and pulmonary vein (PV) anatomy may potentially relate to technical challenges in achieving stable and effective catheter position in case of atrial fibrillation (AF) ablation by means of "one-shot" catheters. The aim of this study was to investigate whether LA volume and PV anatomy, evaluated by computed tomography (CT) or magnetic resonance (MR) prior to ablation, predict acute and midterm outcome of AF ablation by nMARQ™.

METHODS

We included 75 patients (mean age 58 ± 11 years, 67 % male) with symptomatic paroxysmal AF. All patients underwent CT/MR scanning prior to catheter ablation to evaluate LA volume and PV anatomy. All the patients underwent PV isolation by nMARQ™, an open-irrigated mapping and radiofrequency (RF) decapolar ablation catheter. Ablation was guided by electroanatomic mapping allowing RF energy delivery in the antral region of PVs from ten irrigated electrodes simultaneously.

RESULTS

Mean LA volume was 75 ± 40 ml. A normal anatomy (4 PVs) was documented in 40 (53 %) patients and abnormal anatomy (common truncus or accessory PVs) in 35 patients. Mean procedural and fluoroscopy times were 94 ± 55 and 8 ± 5 min, respectively, without significant differences among patients with normal or abnormal anatomy (92 ± 45 vs 95 ± 64 min, p = 0.85 and 6 ± 3 vs 8 ± 4 min, p = 0.65, respectively). Mean ablation time was 14 ± 3 min, and 99 % of the targeted veins were isolated with a mean of 23 ± 5 RF pulses per patient. After a mean follow-up of 17 ± 8 months, 23 (31 %) patients had an atrial arrhythmia recurrence. Neither LA volume nor PV anatomy was a predictor of outcome.

CONCLUSIONS

LA volume and PV anatomy did not affect procedural data and outcome in patients who underwent PV isolation by an open-irrigated mapping and RF decapolar ablation catheter.

Pulmonary vein orientation assessment: Is it necessary in patients undergoing contact force sensing guided radiofrequency catheter ablation of atrial fibrillation

Purpose

We hypothesized that pulmonary vein (PV) orientation influences tissue contact of the contact force (CF) sensing radiofrequency ablation catheter (CFC) and therefore atrial fibrillation (AF) free survival after pulmonary vein isolation (PVI). The aim of this study was to determine the association between PV orientation, CF and AF free survival in patients undergoing CFC PVI.

Methods

Sixty consecutive patients undergoing CFC PVI were included. ECG-triggered cardiac CT scans were obtained in all patients before PVI, and the PV orientation was measured at the insertion in the LA for all PVs in both the transverse and frontal plane. PVs were assigned to 1 of 4 orientation groups: ventral–caudal, dorsal–caudal, ventral–cranial and dorsal–cranial.

Results

Mean age was 59 years, 88% had paroxysmal AF. AF free survival off anti-arrhythmic drugs after a median follow-up of 12 months was 58% after a single PVI procedure. No association was found between PV orientation and CF. Furthermore, no association was found between PV orientation and AF free survival. In univariate analysis, the number of lesions with a mean CF of 10 g was associated with AF free survival. However, in multivariate analysis, only the AF duration was significantly associated with AF free survival.

Conclusions

This study shows that in patients undergoing PVI with the CFC ablation system, PV orientation does not affect CF and is not associated with AF free survival. PV orientation assessment does not appear to be necessary in patients undergoing CFC PVI.

Outcomes Of Cryoballoon Ablation Of Atrial Fibrillation: A Comprehensive Review

Over the last decade, cryoballoon ablation has emerged as an effective alternate strategy to point-by-point radiofrequency ablation for treatment of symptomatic atrial fibrillation. There are several reasons for this. First, the acute and long-term safety and efficacy associated with cryoablation appear comparable to that of radiofrequency ablation in patients with both paroxysmal and also persistent atrial fibrillation. Second, cryoablation offers certain advantages over conventional radiofrequency ablation including a gentler learning curve, shorter ablation and procedure times as well as lack of need for costly electroanatomical mapping technologies commonly utilized with radiofrequency ablation. Lastly, with the recent advent of the second-generation cryoballoon, the effectiveness of cryoablation has further improved dramatically. This comprehensive review examines the gradual evolution of the cryoablation tools as well as the rationale and data in support of the currently-available cryoballoon technologies for catheter ablation of atrial fibrillation.