Author + information
- Received January 4, 2016
- Revision received January 11, 2016
- Accepted January 14, 2016
- Published online August 1, 2016.
- Hanney Gonna, MBBS, BSc,
- Giulia Domenichini, MD, PhD,
- Sergio Conti, MD,
- John Gomes, MBBS, BSc,
- Hariharan Raju, MBChB, PhD and
- Mark M. Gallagher, BSc, MD∗ ()
- Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, St. George's, University of London, London, United Kingdom
- ↵∗Reprint requests and correspondence:
Dr. Mark M. Gallagher, St. George's University Hospitals NHS Foundation Trust, Clinical Academic Group, St. George’s Hospital, Blackshaw Road, London SW17 0QT, United Kingdom.
A 54-year-old woman was found to have recurrent tachycardia arising from her superior vena cava (SVC) during pulmonary vein isolation for paroxysmal atrial fibrillation. Application of cryotherapy to the junction between SVC and right atrium gave clear isolation of the SVC, with continued episodes of rapid disorganized electrical activity in it that were no longer conducted to the atrium. In 2 years of follow-up after ablation, the patient has had no further arrhythmia.
A 54-year-old woman with paroxysmal AF underwent ablation. A 23-mm Arctic Front Advance cryoballoon (Medtronic, Minneapolis, Minnesota) ablation was used to isolate each pulmonary vein (PV), guided by a 20-mm Achieve Mapping Catheter (Medtronic). Runs of atrial tachycardia persisted after the last PV had been isolated.
Tachycardia was mapped to the SVC. With the Achieve in the SVC, the Arctic Front was inflated in the right atrium and advanced until it met the resistance of the SVC-right atrial junction. Contrast injection verified the occlusion produced. The Arctic Front delivered cryotherapy (Figure 1), producing isolation of the SVC. Electrical stimulation via the SVC with manual palpation of the abdomen was used to monitor phrenic nerve function.
The first cryotherapy was stopped at 33 s due to weakened phrenic response; this recovered within seconds. A second delivery was stopped at 74 s for similar reasons. The Achieve showed continued rapid electrical activity in the SVC after isolation (Figures 2 and 3), with sinus rhythm in the heart. More than 2 years later, the patient remains free of arrhythmia.
Ablation in the SVC endangers the phrenic nerve. We took precautions as when treating the right PVs, although electromyography could also be used. The safety of cryotherapy in this site is untested.
Dr. Gallagher has received unrestricted educational grants from Medtronic and Biosense Webster; and speakers fees from Medtronic. Dr. Gonna has received unrestricted educational grants from Boston Scientific and Biosense Webster. All other authors have reported that they have no relationships relevant to the contents of this paper to report.
- Received January 4, 2016.
- Revision received January 11, 2016.
- Accepted January 14, 2016.
- American College of Cardiology Foundation