Radiofrequency Ablation to Prevent Sudden Cardiac Death

Prevalence and incidence of adverse events with catheter ablation for adults with Wolff-Parkinson-White syndrome: a systematic review protocol

OBJECTIVE

The objective of this review is to synthesize the best available evidence to determine the prevalence and incidence of adverse events in patients with Wolff-Parkinson-White syndrome who have undergone catheter ablation.

INTRODUCTION

Wolff-Parkinson-White syndrome is a rare congenital heart disease affecting the normal cardiac conduction system that predisposes an individual to tachyarrhythmias. Patients with Wolf-Parkinson-White syndrome can experience a wide range of life-threatening symptoms and frequently undergo catheter ablation procedures to treat this disease. These patients are at risk of developing a variety of adverse events, including pericardial effusion, cardiac tamponade, atrial fibrillation, stroke, cerebral hemorrhage, major bleeding or hematoma, deep vein thrombosis, atrioventricular-block, cardiac perforation, coronary artery injury, pulmonary emboli, and death.

INCLUSION CRITERIA

This review will include adults aged 18 or older with a diagnosis of Wolff-Parkinson-White syndrome who have undergone catheter ablation, including radiofrequency ablation and cryoablation.

METHODS

MEDLINE, CINAHL, Scopus, Embase, and Web of Science databases will be searched from 1980 to the present for English-language studies only. Prevalence and incidence data, experimental, quasi-experimental, observational, and descriptive studies will be included and critically appraised by two independent reviewers. Data will be extracted using the standardized data extraction tool for prevalence data. If sufficient data is available, a meta-analysis will be conducted; otherwise, the findings will be presented in narrative form including tables and figures to aid in data presentation where appropriate.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42020180391.

Assessment of a novel cryoablation device for the endovascular treatment of cardiac tachyarrhythmias

Objectives

Cryoablation is an effective alternative treatment for cardiac arrhythmias offering shortened recovery and reduced side effects. As the use of cryoablation increases, the need for new devices and procedures has emerged. This has been driven by technological limitations including lengthy periods to generate a single lesion (3-5 min), uncertain transmurality, and differential efficacy. Furthermore, due to limited ablation capacity under high heat loads, cryo has had limited success in the treatment of ventricular arrhythmias. To this end, in this study we evaluated a new cryoablation catheter, ICEolate, for the targeted ablation of cardiac tissue.

Methods

Performance assessment included calorimetry, freeze zone isothermal distribution characterization and catheter ablation capacity in a submerged, circulating, heat-loaded ex vivo tissue model. A pilot in vivo study was also conducted to assess ablative capacity of the cryocatheter in a fully beating heart.

Results

Ex vivo studies demonstrated ice formation at the tip of a cryocatheter within 5 s and a tip temperature of ~-150°C within 10 s. The device repeatedly generated freeze zones of 2 cm × 3 cm in less than 2 min. Tissue model studies revealed the generation of a full thickness (5-10 mm) cryogenic lesion within 1 min with an opposite (transmural) surface temperature of <-60°C under a circulating 37°C heat load. Pilot in vivo studies demonstrated the delivery of an ablative "dose," producing a continuous full thickness transmural linear lesion in <60 s at both atrial and ventricular sites.

Conclusion

These studies suggest that the supercritical nitrogen cryodevice and ICEolate cryocatheter may provide for rapid, effective, controllable freezing of targeted tissue. The ablative power, speed, and directional freeze characteristics also offer the potential of improved safety via a reduction in procedural time compared to current cryoablation devices. These technological developments may open new avenues for the application of cryo to treat other cardiac arrhythmogenic disorders.