Reduction of Iatrogenic Atrial Septal Defects with an Anterior and Inferior Transseptal Puncture Site when Operating the Cryoballoon Ablation Catheter

The overall goal of the following experiment is to facilitate effective cryoballoon occlusion, which will then result in pulmonary vein isolation and return to normal sinus rhythm. This is accomplished by first finding the fossa, vals, or FO location. Next, the location, low and anterior to the FO is identified.

Then transseptal needle entry is performed. Finally, heparin is injected and activated clotting time is checked. Ultimately, fluoroscopy and intracardiac echocardiography or ice are used to show the location of transseptal entry and balloon occlusion is used as a measure of success.

So this is a methodology to describe in detail how we do cry bone ablation with intention to have a more anterior and inferior transseptal puncture site. The idea is that you, with this site, it will have a better mechanical advantage to perform the pulmonary vein isolation, which is critical in curing atrial fibrillation. And this will also leave a less likelihood of atrogenic atrial septal defect On the day of the atrial fibrillation or AF ablation procedure, assess the left atrium or LA or thrombus presence or formation.

If a thrombus is absent, use general anesthesia to sedate the patient or agents to establish conscious sedation. Do not use a paralytic agent so that phrenic nerve monitoring can be used during the ablation. Use intracardiac, echocardiography or ICE to examine the patient immediately after transseptal puncture.

Administer a heparin bolus according to the patient's weight, and then give supplemental doses of heparin throughout the procedure with the goal of maintaining active clotting time between 350 and 400 seconds to carry out the AF ablation procedure. Begin by using a Mullins type sheath under ICE guidance to perform a transseptal catheterization, bend the transseptal needle about half an inch from the distal tip. According to the text protocol.

Position the transseptal needle at the septum to avoid aortic puncture and to safeguard against LA lateral wall needle puncture. To reach the inferior limbus or IL Transseptal location, enter about one centimeter below the traditional FOSS vallis or FO site, and at an anterior septal location. The IL location is found through a valuation of ice and fluoroscopy once the FO site is established.

Next, use ice plane imaging to define the entry point in the IL location and sweep the ice image anterior towards the plane of the mitral valve. To define the anterior position of the site, the inferior location will be dependent on the il, which is triangular and cross-section. Place the transseptal needle puncture at the center of this triangular area.

Finally, establish the transseptal access route by exchanging the transseptal needle with a guide wire to perform cryoballoon ablation. Begin by using the guidewire to introduce the cryoballoon sheath. Then through the sheath, deploy the cryoballoon catheter and the dedicated inter lumen circular mapping catheter into the LA inflate the cryoballoon and advance it over the inner lumen circular mapping catheter, which is wired towards the PD osteum.

Inject five to 10 milliliters of radiopaque contrast agent through the cryoballoon catheter in lumen. Confirm cryoballoon to PDV occlusion by using the retention of contrast agent after injection at the distal tip of the balloon. Also confirmed by ice imaging under color flow doppler using the lack of flow around the balloon anterior surface as an indicator of occlusion.

Once occlusion is established, start the cryoballoon cryoablation by pressing the start button on the cryo console. This will push cryo refrigerant into the cryoballoon catheter and initiate cryoablation on the right-sided pvs. Insert a diagnostic catheter in the right atrial superior vein conval junction, and position it to pace the right phrenic nerve.

Pace the phrenic nerve at 20 milliamps amplitude and 2.0 millisecond pulse width and monitor phrenic nerve function by manual detection of diaphragmatic contractions. Immediately terminate an ablation. If phrenic nerve function is diminished, delayed or lost.

Deliver a minimum of two freezes each lasting 120 to 180 seconds while using the inter lumen circular mapping catheter to monitor both realtime and post ablation PVI through entrance and exit block testing. Once entrance and exit block is established at each pv, withdraw the cryoballoon sheath and inter lumen circular mapping catheter. Use standard medical care to stop bleeding at vascular entry points and discharge patients via hospital protocols, which may include anticoagulation pharmaceutical therapy and guidance on anti-arrhythmic drugs.

This figure demonstrates how tenting of the FO can help determine an inferior and anterior transseptal location near the IL.That allows the cryoballoon catheter to be used with minimal catheter and or sheath deflection with ablations in the lower pvs. The IL transseptal location allows for a more direct alignment between the cryoballoon catheter and the tubular section of each pv. As shown here.

Alignment between the PV and cryoballoon catheter allows for the most direct transfer of occlusion force that is necessary to ensure that a complete and circumferential lesion is created surrounding each PV during the cryoballoon ablation procedure. Another acute advantage of using the IL location during a cryoballoon ablation procedure is that it is in a thicker part of the septum than the FO location. Consequently, when the cryoballoon and sheath are removed from the LA, there is less left to right shunting of blood compared to the FO location, and in some cases there is no detectable blood shunting when viewed by color flow Doppler imaging.

In conclusion, after watching this video, you'll be able to use the intracardiac echo as well as fluoroscopy to guide you for a more anterior and inferior transseptal puncture site. This will give you a mechanical advantage for cry balloon ablation, as well as reduce the risk of atrogenic atrial septal defects.