Systematic Workflow and Electrogram guidance to reduce X-ray Exposure Time during cryoballoon ablation of atrial fibrillation: the SWEET-Cryo strategy

Cryoballoon Pulmonary Vein Isolation in Obese Patients with Atrial Fibrillation Compared to Non-Obese Counterparts: A Meta-Analysis

Introduction: Obesity is an important risk factor for atrial fibrillation (AF) development. Data on cryoballoon ablation (CBA) outcomes in obese patients have so far been scarce. We reviewed the existing literature to compare the efficacy and safety of CBA in obese versus non-obese AF patients. Methods: A systematic literature search was conducted for studies comparing clinical outcomes (arrhythmia recurrence and/or procedural data and/or safety outcomes) between obese and non-obese patients undergoing CBA for AF. Statistical pooling was performed according to a random-effects model with generic inverse-variance weighting of relative risks (RRs) and standardised mean differences (SMDs) computing risk estimates with 95% confidence intervals (CIs). Results: Obese and non-obese patients had comparable arrhythmia recurrence rates (normal versus overweight, RR = 0.95, 95% CI: 0.82-1.11, p = 0.55, I2% = 91%; normal versus class I obesity, RR = 0.97, 95% CI: 0.82-1.13, p = 0.68, I2% = 87%; normal versus class II obesity, RR = 0.98, 95% CI: 0.91-1.07, p = 0.29, I2% = 65%). Procedure time was marginally increased in obese patients compared to non-obese counterparts (normal versus overweight, SMD = 0.05, 95% CI: -0.15-0.26, p = 0.62, I2% = 74%; normal versus class I obesity, SMD = 0.10, 95% CI: -0.00-0.19, p = 0.06, I2% = 2%; overweight versus class I obesity, SMD = 0.11, 95% CI: 0.01-0.21, p = 0.048, I2% = 25%). Regarding radiation exposure, fluoroscopy time was increased in patients with class I obesity compared to normal-weight or overweight patients and dose area product was also increased in obese patients compared to non-obese patients. Lastly, the risk of complications did not differ between obese and non-obese patients. Statistical heterogeneity and the small number of patients included are the main limitations of this study. Conclusion: CBA seems to be effective for obese patients suffering from AF, featuring also similar safety outcomes with non-obese individuals. Radiation exposure was increased in obese patients.

Achieving reduced radiation exposure with maintained fluoroscopy effectiveness using ultralow-dose settings in cryoballoon ablation

Background and Aims

Optimization of fluoroscopic image quality for reducing radiation exposure in cryoballoon pulmonary vein isolation (CB-PVI) has not yet been fully investigated. Therefore, we tried to compare the radiation doses among three different X-ray system settings.

Methods

Consecutive 148 patients scheduled for their first CB-PVI were prospectively enrolled: low dose with the use of an anti-scatter grid for the first 51 patients (LD + G group), low dose without an anti-scatter grid for the subsequent 46 patients (LD-G group), and ultralow dose (ULD group) with an anti-scatter grid for the remaining 51 patients. We compared the radiation doses required to complete CB-PVI procedures among the groups. There were 27 patients for whom CB-PVI was performed without cine acquisition, but with fluoroscopy only, and the radiation doses were also compared.

Results

The median procedure time and fluoroscopy time were 119 and 35.5 min, respectively, with no significant differences among the groups. The median cumulative air Kerma (AK) decreased in both the LD-G group (71.8 mGy, p < .001) and the ULD group (73.0 mGy, p < .001), compared to the LD + G group (145.0 mGy). Among 27 patients who underwent CB-PVI without cine acquisition, the median cumulative AK further decreased in both the LD-G group (31.4 mGy, p < .05) and the ULD group (22.7 mGy, p < .01), compared to the LD + G group (64.6 mGy).

Conclusion

Using an ULD X-ray setting and avoiding cine acquisition, we can reduce radiation exposure, while ensuring the necessary fluoroscopy time for the CB-PVI procedure.

Impact of Body Mass Index on the Outcomes of Cryoballoon Pulmonary Vein Isolation for Paroxysmal Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is prevalent among obese patients, and cryoballoon ablation (CBA) is an effective strategy for the rhythm control of AF. The impact of body mass index (BMI) on the clinical outcomes of CBA for AF is not fully explored.

METHODS

85 consecutive patients with paroxysmal AF were enrolled and were categorized into three groups as per their BMI: normal weight (BMI 18.5-25 kg/m2), overweight (BMI 25-30 kg/m2), and obese patients (BMI > 30 kg/m2). The primary study endpoint was a late (12 month) recurrence of AF. Early recurrence of AF, symptom improvement, and procedural outcomes were some key secondary outcomes.

RESULTS

20 patients had normal weight, 35 were overweight, and 30 were obese. Obese patients featured a higher prevalence of diabetes mellitus, heavier exposure to smoking, and worse baseline symptoms (as assessed through EHRA class at admission and 12 months before CBA) compared to overweight and normal weight patients. Both late and early (<3 months) AF recurrence rates were comparable across the three groups. Of note, obese patients showed greater improvement in their symptoms post-CBA, defined as improvement by at least one EHRA class, compared to normal weight patients; this might be explained by improved diastolic function. Total procedure time and dose area product were significantly increased in obese patients. The multivariate logistic regression analysis indicated that early AF recurrence and the duration of hypertension are independent predictors of late AF recurrence.

CONCLUSION

CBA is effective in overweight and obese patients with paroxysmal AF. Procedure time and radiation exposure are increased in obese patients undergoing CBA.

Integrated dilator-needle transseptal crossing device in atrial fibrillation cryoballoon ablation procedures

INTRODUCTION

In cryoballoon ablation (CBA) procedures, transseptal access (TSA) is generally achieved using a standard sheath and needle system that is exchanged for the cryoballoon delivery sheath and dilator over a long wire. Sheath exchange has been related with air embolic events. Recently, an integrated dilator-needle system assembled to the cryoballoon sheath was introduced. We aimed to evaluate the efficacy and safety of an integrated TSA tool compared with the traditional approach in atrial fibrillation CBA procedures.

METHODS

Patients scheduled for CBA procedures were randomized 1:1 to traditional TSA (t-TSA) or integrated TSA (i-TSA). TSA time was defined as time from superior vena cava to LA insertion of the cryoballoon delivery sheath, after sheath exchange (t-TSA) or directly (i-TSA).

RESULTS

Ninety-seven patients (76 males, mean age 59 ± 10 years) were randomized, 48 patients underwent t-TSA, and 49 i-TSA. Mean TSA time was 5 min 59 s ± 5 min 36 s in the t-TSA group and 2 min 59 s ± 2 min 14 s in the i-TSA group (p < .001). Total fluoroscopy time, skin-to-skin procedure time, and LA dwell time were respectively 15 ± 6, 69 ± 16, and 44 ± 12 min in the t-TSA group and 13 ± 6, 65 ± 15, and 43 ± 11 min in the i-TSA group (p = ns). No clinically significant acute complications related to TSA were noted in both cohorts.

CONCLUSION

This is the first randomized study comparing both TSA approaches. TSA in CBA procedures using this integrated tool enables a safe and efficient workflow, reducing TSA time and avoiding sheath exchange.