Hot balloon versus cryoballoon ablation in patients with atrial fibrillation: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) incidence is expected to increase more than 60% in the following 30 years. Catheter ablation is the treatment of choice for medically intractable AF with arrhythmia recurrence remaining an unsolved issue.

Purpose

We systematically reviewed existing literature to compare the efficacy of hot balloon (HBA) versus cryoballoon ablation (CBA).

Methods

PubMed, Scopus, ClinicalTrials.gov, medRxiv and Cochrane Library (according to PRISMA guidelines) were scrutinized for relevant articles up to 2 December 2021. Eligible studies had to compare clinical outcomes (arrhythmia recurrence rates or/and procedural data or/and safety outcomes) between patients undergoing HBA and CBA for AF. Quality assessment of studies was conducted via the Newcastle-Ottawa Scale (high quality≥ 7, moderate 4-6, poor <4). Statistical pooling was performed according to a random-effect model with generic inverse-variance weighting of odds ratios and mean differences computing risk estimates with 95% confidence intervals. The presence of heterogeneity among studies was evaluated under the Cochran Q chi-square test. I² values of 25%, 50% and 75% have been assigned adjectives of low, moderate, and high heterogeneity. Publication biases were assessed by visual inspection of funnel plots.

Results

PRISMA study search and individual study characteristics are presented in Figure 1. Literature search identified 131 studies, 5 of which (evaluating 513 patients) met inclusion criteria. Patients undergoing HBA demonstrated similar long term recurrence rate as compared to CBA treated controls (OR: 0.68; 95% CI: 0.38-1.22; p-value: 0.19; I2: 0%). Procedural aspects, such as touch-up radiofrequency ablation (per pulmonary vein), procedure time (min) and fluoroscopic time (min) did not differ among treatment arms (OR: 1.79; 95% CI: 0.84-3.83; p-value: 0.13, I2: 80%, MD: 9.69; 95% CI: -2.78-22.16; p-value: 0.13, I2: 63%, and OR: 1.03; 95% CI: -9.50-7.44; p-value: 0.81, I2: 87%, respectively). Regarding safety outcomes (Figure 1), the small number of the reported events precluded us from analyzing these data. Yet, tamponade and phrenic nerve injury were infrequent in both modalities; pulmonary vein stenosis of at least moderate severity (>50% luminal narrowing) was reported in 18 instances in the HBA arm as compared to zero events in the CBA arm. Of note, all events were asymptomatic. Quality assessment scores are shown in Figure 1. Four studies were of high quality and one study was of moderate quality. Funnel-plot distributions of the pre-specified outcomes indicated absence of publication bias for all outcomes. High statistical heterogeneity and the small number of patients included are the main limitations of this study.

Conclusion

Hotballoon ablation is a promising therapeutic option for patients suffering from AF, featuring comparable efficacy and procedural outcomes with cryoablation. Safety outcomes, especially PV stenosis, mandate further evaluation.

Subclavian versus axillary vein puncture for implantation of cardiac electronic devices. A meta-analysis

Background

Implantation of CIED has become a daily practice for patients with rhythm disturbances, those with an indication for primary or secondary sudden cardiac death prevention as well as for patients with heart failure and marked ventricular dyssynchrony. Most of the complications observed following implantation seem to be procedure-related. The latter has led many physicians to replace the classic subclavian approach with alternative techniques such as cephalic vein cut-down and axillary vein puncture (AVP). Recent data support that these techniques may be associated with similar success rates and lower adverse events.

Purpose

This meta-analysis was performed to compare axillary to subclavian vein puncture (SVP) for implantation of cardiac implantable electronic devices (CIED), in terms of safety and efficacy.

Methods

We searched MedLine, via PubMed, for studies comparing subclavian to axillary vein approach in terms of safety and efficacy. Safety endpoints were considered the incidence of pneumothorax, device related infections and major bleeding events. Efficacy and feasibility were assessed by the incidence of lead failure (lead dislodgement, lead fracture or insulation defects) and the number of successfully cannulated veins, respectively. Studies were judged as eligible if they reported at least one of the predefined outcomes. Effect size was calculated using the risk difference along with the corresponding 95% confidence interval (CI). A random- effects DerSimonian-Laird model was adopted.

Results

Seven studies fulfilled the inclusion criteria and were included in the final analysis, resulting in 3642 patients (59.1% males) with a pooled mean (SD) age of 66.1 (12.7) years. Axillary vein puncture (AVP) was performed in 45.8% of them. All, but one study, used fluoroscopic guidance (with or without venography) for axillary vein cannulation. The CIED most commonly implanted was a permanent pacemaker (73%). Both techniques resulted in similar percentages of successful cannulations (1066/1099 for AVP and 906/931 for SVP, RD: 0; 95% CI: −0.01–0.01, I2: 0%, Figure 1A). There was a significantly higher risk for pneumothorax with the subclavian approach (RD: 0.02; 95% CI: 0.01–0.03, I2: 49.31%, Figure 2A). No significant differences were observed regarding the incidence of bleeding and infections (Figure 2B, 2C). SVP was also associated with a significantly increased risk for lead failure (RD: 0.01; 95% CI: 0.00–0.03, I2: 48.47%, Figure 1B).

Conclusions

AVP seems to be a feasible approach for implantation of CIED. Moreover, it seems to be both a more safe and effective choice compared to SVP, as it is associated with reduced risk for pneumothorax and lead failure. More data especially comparing AVP to cephalic cut-down are needed to safely guide the daily practice.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Is there an antiarrhythmic benefit from switching to sacubitril/valsartan therapy? A systematic review and meta-analysis

Background

Sacubitril/valsartan through reverse structural remodeling and neurohormonal inhibition could play an antiarrhythmic role.

Purpose

This systematic review and meta-analysis was performed to explore the arrhythmiologic effects of switching patients with heart failure with reduced ejection fraction (HFrEF) from angiotensin converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARBs) to sacubitril/valsartan.

Methods

We searched major databases for studies comparing device-detected, incident atrial and ventricular arrhythmias in patients with HFrEF while on ACEi/ARBs versus while on sacubitril/valsartan. For pooling the primary outcome of interest, we calculated the risk difference (RD) with the corresponding 95% confidence interval (CI) in the probability of experiencing each arrhythmic event while on ACEi/ARBs and while on sacubitril/valsartan. A random effects (DerSimonian-Laird) model was adopted.

Results

We analyzed 4 eligible studies, resulting in 497 patients with a pooled mean age of 67.8±10.36. 64% had ischemic cardiomyopathy while 98% had either an implantable cardioverter defribrillator or a cardiac resynchronization therapy device. Main comorbidities were hypertension (68.7%) and dyslipidemia (59.6%). Almost all (96.3%) patients were treated with b-blockers and 23.7% were also receiving anti-arrhythmic drugs, mainly amiodarone. After switching to sacubitril/valsartan there was a trend towards reduced risk for sustained ventricular tachycardia/fibrillation and non-sustained ventricular tachycardias (RD: −0.04, 95% CI: −0.09–0.02, I2: 65.7% and −0.06, 95% CI: −0.19–0.07, I2: 85%; respectively). Meta-regression analysis showed that patients with ischemic cardiomyopathy experience greater benefit. Incident paroxysmal atrial fibrillation/tachycardia was significantly reduced (RD: −0.09 95% CI: −0.14 to −0.03, I2: 0%), while favorable effects were noticed for the risk of appropriate shock delivery and inadequate biventricular pacing (RD: −0.06, 95% CI: −0.09 to −0.03, I2: 0% and −0.06, 95% CI: −0.11 to 0.00, I2: 35.55%, respectively). All results seem to suffer from publication bias.

Conclusion

Limited data support that switching to sacubitril/valsartan seems to be associated with reduced risk for both ventricular and atrial arrhythmias. More studies are needed to clarify the potential anti-arrhythmic role of this drug. Whether patients with frequent arrhythmias or at high arrhythmic risk may benefit from early switch is a matter of further investigation.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Short-term fluctuations of plasma NT-proBNP levels in patients with new-onset atrial fibrillation: a way to assess time of onset?

OBJECTIVE

The objective of this study was to characterise short-term kinetics of plasma amino-terminal pro-B natriuretic peptide (NT-proBNP) levels in patients with new-onset atrial fibrillation (AF) without heart failure.

DESIGN

Prospective cohort study.

SETTING

Emergency departments and inpatient services of three large community hospitals.

PATIENTS

31 consecutive patients with new-onset atrial fibrillation (<24 h before presentation) persisting at least 48 h, without evidence of heart failure.

MAIN OUTCOME MEASURES

Plasma NT-proBNP levels were obtained at presentation and then 6, 12, 18, and 24 h after presentation. A final sample was obtained 48 h after onset of AF.

RESULTS

Mean plasma NT-proBNP levels and 95% CIs (pg/ml) during the 48-h period following onset of AF were: 0-6 h: 636 (395 to 928), 6-12 h: 1364 (951 to 1778), 12-18 h: 1747 (1412 to 2083), 18-24 h: 1901 (1549 to 2253), 24-36 h: 1744 (1423 to 2066) and 36-48 h: 1101 (829 to 1373). Mean time to peak NT-proBNP levels was 16.7 (0.7) h; 29 patients reached their peak levels within 24 h. The mean peak NT-proBNP level was significantly higher than those obtained at 0-6 h and at 36-48 h after onset of AF (p<0.001 for both). There was no correlation between ventricular rate and plasma NT-proBNP levels during any time period after onset of AF.

CONCLUSION

In patients with new-onset AF but no clinical or radiographic evidence of heart failure, plasma NT-proBNP levels rise progressively to a peak during the first 24 h and then rapidly fall. This pattern may serve as an aid to assess the time from AF onset.