Fossa ovalis radiofrequency perforation in a difficult case of conventional transseptal puncture for atrial fibrillation ablation. J Interv Card Electrophysiol. 2008;21:249-253. [PMID: 18274714 DOI: 10.1007/s10840-007-9194-x]

Difficult case of a trans-septal puncture: Use of a “SafeSept” guidewire

A 69-year-old man was admitted to our center to undergo catheter ablation of paroxysmal atrial fibrillation refractory to antiarrhythmic drug therapy. This procedure required access to the left atrium through the interatrial septum. During hospitalization, the patient performed routinely pre-procedure transthoracic echocardiography and gadolinium-enhanced cardiac magnetic resonance showing a normal anatomy of both the fossa ovalis and the interatrial septum. Access to the left atrium proved difficult and several unsuccessful attempts to perform the trans-septal puncture were made under both fluoroscopy and intracardiac echocardiography guidance, even with radiofrequency energy delivery. Finally, trans-septal puncture was successfully carried out using a novel nitinol J-shaped “SafeSept” trans-septal guidewire, designed to cross the interatrial septum through the trans-septal needle thanks to a special sharp tip. Moreover, thanks to its rounded J shape that reduces the risk of atrial perforation, the “SafeSept” guidewire, when advanced into the left atrium, becomes atraumatic.

Role of Intracardiac echocardiography in Atrial Fibrillation Ablation

In the recent years, several new evidences support catheter-based ablation as a treatment modality of atrial fibrillation (AF). Based on a plenty of different applications, intracardiac echocardiography (ICE) is now a well-established technology in complex electrophysiological procedures, in particular in AF ablation. ICE contributes to improve the efficacy and safety of such procedures defining the anatomical structures involved in ablation procedures and monitoring in real time possible complications. In particular ICE allows: a correct identification of the endocardial structures; a guidance of transseptal puncture; an assessment of accurate placement of the circular mapping catheter; an indirect evaluation of evolving lesions during radiofrequency (RF) energy delivery via visualization of micro and macrobubbles tissue heating; assessment of catheter contact with cardiac tissues. Recently, also the feasibility of the integration of electroanatomical mapping (EAM) and intracardiac echocardiography has been demonstrated, combining accurate real time anatomical information with electroanatomical data. As a matter of fact, different techniques and ablation strategies have been developed throughout the years. In the setting of balloon-based ablation systems, recently adopted by an increasing number of centers, ICE might have a role in the choice of appropriate balloon size and to confirm accurate occlusion of pulmonary veins. Furthermore, in the era of minimally fluoroscopic ablation, ICE has successfully provided a contribute in reducing fluoroscopy time. The purpose of this review is to summarize the current applications of ICE in catheter based ablation strategies of atrial fibrillation, focusing-on electronically phased-array ICE.

Use of a novel needle wire in patients undergoing transseptal puncture associated with severe septal tenting

INTRODUCTION

An increasing number of patients undergo left atrial ablation procedures, since several approaches have proven efficacy in the treatment of atrial fibrillation. Although transseptal catheterization was generally shown be a safe technique, it harbors the principal risk of cardiac injury. Therefore, there is a need for a safe and effective tool to enable transseptal puncture in difficult cases as well.

METHODS AND RESULTS

In 158 consecutive patients, a transseptal puncture was intended for mapping and ablation of left atrial tachycardias. In seven patients of this series transseptal puncture using different sheaths and needle designs, the operators failed to cross the interatrial septum as a result of severe tenting. Three patients were known to have a septal aneurysm; a redo procedure was performed in two patients. In the remaining patients, there was no obvious explanation for the difficulty in crossing the interatrial septum conventionally. In all seven patients, a 120-cm-long nitinol guidewire ("needle wire") with a 0.014-inch diameter was used to cross the atrial septum with the following idea: after tenting the fossa ovalis with the transseptal dilator and the Brockenbrough needle positioned just inside the tip, effortless advancement of the needle wire perforates the membranous fossa. Unsupported by the needle and dilator, the tip of the wire immediately assumes a "J" shape, rendering it incapable of further tissue penetration after its entry into the left atrium. In all seven patients, the needle wire could be placed into a left pulmonary vein. In five patients, a single attempt was sufficient to reach the left atrium with the wire, two patients needed two and three attempts, respectively. No complications occurred.

CONCLUSIONS

Additional use of a needle wire to perform transseptal puncture in a subset of patients at higher risk for complications appears safe and effective.

Use of a novel sharp-tip, J-shaped guidewire to facilitate transseptal catheterization

AIMS

Transseptal catheterization (TSP-C) is a demanding procedure and at the same time one of the key points of atrial fibrillation ablation, an increasingly diffused procedure. This study prospectively evaluates the usefulness of a novel sharp-tip, J-shaped 0.014'' transseptal guidewire (TSP-GW) to facilitate TSP-C in case of resistant atrial septum (AS).

METHODS AND RESULTS

Consecutive patients undergoing TSP-C for arrhythmia ablation in a single centre were considered for the study. TSP-C was performed according to a standardized technique. The criterion to use the TSP-GW was a resistant AS, defined as inability to perforate the fossa ovalis by applying moderate pressure to a standard Brockenbrough needle. The TSP-GW was inserted in the needle lumen and advanced to puncture the AS and enter the left atrium; subsequently, the transseptal assembly was advanced over the TSP-GW. Double transseptal puncture was routinely performed for ablation of atrial fibrillation. Eighty-one patients (54 males, 27 females; mean age 54 +/- 17 years, range 12-81) undergoing TSP-C were enrolled; 132 TSP-C procedures were planned and accomplished. Nineteen patients (23%) in 27 procedures showed a resistant AS. In all these procedures, the TSP-GW was safely and successfully used to accomplish the TSP-C. In patients with a resistant AS, only a significantly lower prevalence of structural heart disease was observed when compared with controls. No complication related to TSP-C was observed.

CONCLUSION

The TSP-GW facilitates TSP-C in 23% of the patients, in whom a resistant AS is encountered. In this population, there was no clinical predictor of such anatomy.

Novel trans-septal approach using a Safe Sept J-shaped guidewire in difficult left atrial access during atrial fibrillation ablation

Nowadays, trans-septal (TS) puncture is a relatively safe and straightforward procedure in experienced hands. However, in the presence of a thick, aneurysmatic or extremely elastic fossa ovalis crossing the septum might be challenging. We here describe the use of a novel guidewire that permits easy and safe 'over the wire' TS access during atrial fibrillation ablation.