A Chill is Here: The Artic Front
A chill is in the wind, and it is just the beginning of the Fall. With Medtronic's release of the Arctic Front® cryoablation system, we now have the ability to isolate the pulmonary veins in patients with symptomatic atrial fibrillation who have failed antiarrhythmic drug therapy. The procedure requires a 15 French steerable sheath and a proprietary balloon catheter, which is first inflated and then filled with liquid nitrogen in order to create the freeze and isolate the vein. Two 4-minute freezes are recommended. Close vigilance for diaphragm paralysis is recommended, since phrenic nerve paralysis may occur with right-sided freezes.
Our initial experience at Winthrop has been positive. Currently we are performing a single transseptal procedure. This procedure may require additional touch up with radiofrequency catheter ablation. We pace the phrenic nerve during right-sided freezes and feel the diaphragm contractions, so we can shut off therapy if the contractions weaken. We are giving protamine at the end of the procedure to reverse heparin, and the venous groin hold has been as long as one hour. We are trying to optimize pulmonary venous occlusion prior to each freeze.
We are using this technique first line for pulmonary vein isolation. Only time will tell whether this will surpass radiofrequency ablation for pulmonary vein isolation in order to treat paroxysmal atrial fibrillation — or perhaps it will serve as an adjunctive therapy?
Overall, with winter approaching, we are excited about this potential new modality to treat atrial fibrillation. In short, a chill is here with the Arctic Front.
Todd J. Cohen, MD, FACC, FHRS is the Emeritus Editor-in-Chief of EP Lab Digest, author of Practical Electrophysiology, and author of the recently published Johns Hopkins Health Book entitled "A Patient's Guide to Heart Rhythm Problems." He is also the Director of Electrophysiology and the Pacemaker/Arrhythmia Center at Winthrop-University Hospital.
