Applying Runthrough Guidewire To Transseptal Puncture Without Iodinated Contrast Agent

Aims: Conventional transseptal puncture(TSP) relies on fluoroscopy and iodinated contrast agent to distinctly position the transseptal needle at the left atrium, however, there exists great challenges in clinic in patients with contrast hypersensitivity or allergy-like reactionsin the procedure. This study aimed to evaluate a novel approach to TSP assisted by Runthrough guidewire and fluoroscopy without use of iodinated contrast agent. Methods: Sixty patients with paroxysmal atrial fibrillation undergone radiofrequency catheter ablation were enrolled from February 2021 to October 2021, and randomised to routine TSP group and Runthrough guidewire assisted group. The two groups were compared regarding the total operative time, length of fluoroscopy exposure, difference of radiation dose in X-ray, and the safety was evaluated in the patients undergone TSP without iodinated contrast agent. Results: There were no differences in baseline demographics or clinical characteristics between the two groups. Although the total procedure time[(1.98±0.29) min vs.(2.11±0.14) min, P<0.04],length of fluoroscopic exposure [(1.83±0.30) vs.(1.98±0.14), P<0.19] and radiation dose in X-ray[(27.83±3.21) uGym2vs.(29.13±1.57) uGym2, P<0.30] were somewhat statistically different between groups, yet the difference was insignificant. No complications, including pericardial tamponade and aortic perforation, occurred in all patients. Conclusion: Iodine-free TSP under the guidance of Runthrough guidewire and fluoroscopy can be a simple, safe, economical and effective approach to TSP, and may be reproduced as a novel option for TSP in patients with contrast hypersensitivity or allergy-like reactions.

Right-to-left Shunt via Iatrogenic Atrial Septal Defect Requiring Emergency Surgical Repair following Cryoballoon Atrial Fibrillation Ablation in a Patient with Arrhythmogenic Right Ventricular Cardiomyopathy

An 81-year-old woman with arrhythmogenic right ventricular cardiomyopathy underwent catheter ablation for atrial fibrillation and atrial flutter. Hypoxemia refractory to the administration of oxygen was seen after transseptal puncture. Transthoracic echocardiography revealed right to left shunt via an iatrogenic atrial septal defect (IASD) that was increased by tricuspid regurgitation flow. Her hypoxemia improved after IASD occlusion with the inflation of a venogram balloon catheter. Emergent surgical IASD closure was successfully performed. IASD after transseptal puncture for atrial fibrillation ablation infrequently causes severe complications that require emergent repair.

Zero-Fluoroscopy Cardiac Ablation: Technology Is Moving Forward in Complex Procedures—A Novel Workflow for Atrial Fibrillation

Background and Rationale. A fluoroscopy-based approach to an electrophysiological procedure is widely validated and has been recognized as the gold standard for a long time. The use of fluoroscopy exposes both the healthcare staff and the patient to a non-negligible dose of radiation. To minimize the risks associated with the use of fluoroscopy, it would be reasonable to perform ablation procedures with zero fluoroscopy. This approach is widely used in simple ablation procedures, but not in complex procedures. In atrial fibrillation (AF) ablation procedures, fluoroscopy remains the main technology used, in particular to guide the transseptal puncture. Main results and Implications. We present a workflow to perform a complete zero-fluoroscopy ablation for AF ablation procedures using a 3D electro-anatomical mapping system, intracardiac echocardiography and a novel steerable guiding sheath that can be visualized on the mapping system. We present two cases, one with paroxysmal AF and the other one with persistent AF during which we applied this novel workflow achieving a successful pulmonary vein isolation without complications and complete zero-fluoroscopy exposure.

Successful treatment of chronic total occlusion of the coronary arteries through the femoral vein: a novel approach

Despite the vessel’s inaccessibility to dual coronary angiography and the use of classical routes for retrograde treatment of chronic total occlusion (CTO), the approach through the femoral vein and subsequent transseptal puncture with catheterization of ostium of coronary arteries is a viable treatment approach.

Cardioneuroablation for Treatment of Atrioventricular Block

Background: The contribution of autonomic influences to atrioventricular block (AVB) is unclear. Although cardioneuroablation has been used to treat cardioinhibitory vasovagal syncope, its role in treating functional paroxysmal and persistent AVB has not been formally evaluated. Methods: We used a stepwise protocol in 241 consecutive patients presenting with symptomatic AVB to identify 31 (12.9%) patients with functional or vagally mediated AVB. All patients had episode(s) of syncope in previous 12 months, and AVB was persistent in 17 (54.8%) patients. All 31 patients received targeted catheter-based cardioneuroablation, and their follow-up outcomes were evaluated with serial Holter monitoring. Results: Twenty-eight patients received biatrial or left-sided cardioneuroablation while 3 received only right-sided cardioneuroablation because of structural factors that precluded safe attempts at transseptal puncture. Procedural success, as defined as acute reversal of AVB and complete abolition of atropine response, was achieved in 30 (96.7%) cases, while the remaining patient received a pacemaker. Over a mean follow-up of 19.3±15 months, AVB episodes were observed in 2 (6.7%) of 30 cases, and 3 (9.6%) patients required pacemaker implantation during follow-up. Conclusions: Functional AVB can be identified in a minority of patients presenting with high-grade AVB. Cardioneuroablation for these patients results in encouraging medium-term outcomes.

Comparing the Safety and Effectiveness of Dedicated Radiofrequency Transseptal Wires to Electrified Metal Guidewires

Application of electrocautery to a metal guidewire can be used to perform transseptal puncture (TSP). Dedicated radiofrequency guidewires (RF) may represent a better alternative. This study compares safety and effectiveness of electrified guidewires to a dedicated RF wire. TSP was performed on porcine hearts using an electrified 0.014” or 0.032” guidewire under various power settings compared to TSP using a dedicated RF wire with 5W power. The primary endpoint was the number of attempts required to achieve TSP. Secondary endpoints included the rate of TSP failure, TSP consistency, effect of the distance between tip of the guidewire and the tip of the dilator, and effect of RF power output level. Qualitative secondary endpoints included tissue puncture defect appearance, thermal damage to the TSP guidewire or dilator, and tissue temperature using thermal imaging. The RF wire required 1.10 ± 0.47 attempts to cross the septum. The 0.014” electrified guidewire required 2.17 ± 2.36 attempts (2.0x higher than the RF wire; p<0.01), and the 0.032” electrified guidewire required 3.90 ± 2.93 attempts (3.5x higher than the RF wire; p<0.01). Electrified guidewires had a higher rate of TSP failure, larger defects, more tissue charring, higher temperatures, and greater tissue heating. Fewer RF applications were required to achieve TSP using a dedicated RF wire compared to an electrified guidewire. Smaller defects and lower tissue temperatures were also observed using the RF wire. Electrified guidewires required greater energy delivery and were associated with equipment damage and tissue charring.