Combined Angiography and Late Gadolinium Enhancement Acquisition to Improve Assessment of Pulmonary Vein Isolation for Atrial Fibrillation

• Type of Material: Article
• Authors: Adrian Lam, Georgia Institute of Technology; Erica Okene, Emory University; Ankit Parikh, Emory University; Xiaodong Zhong, Emory University; Thor Tejada, Emory University; Michael Hoskins, Emory University; Michael Lloyd, Emory University; John Oshinski, Emory University
• Language: English
• Date: 2018-02-01
• Publisher: Wiley
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2017 International Society for Magnetic Resonance in Medicine.
• Final Published Version (URL): http://dx.doi.org/10.1002/jmri.25771
• Title of Journal or Parent Work: Journal of Magnetic Resonance Imaging
• ISSN: 1053-1807
• Volume: 47
• Issue: 2
• Start Page: 477
• End Page: 486
• Grant/Funding Information: This work was supported by grant HL109979 from the National Institutes of Health (Oshinski) and a Grant-in-Aid from the American Heart Association (Oshinski).
• Keywords: SCAR; EXTENT; cryoballoon ablation; CRYOBALLOON; Radiology, Nuclear Medicine & Medical Imaging; RF ABLATION; pulmonary vein isolation; cardiovascular MRI; atrial fibrillation; MRI; Science & Technology; late gadolinium enhancement; INJURY; RECURRENCE; Life Sciences & Biomedicine
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Radiology

Abstract

Purpose: To develop a Shared K-space (SharK) magnetic resonance imaging (MRI) sequence that combines angiographic and late gadolinium enhancement (LGE) acquisitions to improve atrial wall segmentation and scar identification, and to develop a novel visualization method that quantifies scar encirclement of pulmonary veins postablation treatment for atrial fibrillation. Materials and Methods: A SharK sequence was developed and used at 3T to image the left atrium in 11 patients postcryoballoon ablation. The effects of sharing k-space between the angiographic and LGE acquisitions on the accuracy of scar were assessed. The left atrial wall was segmented and points about each pulmonary vein (PV) ostia were projected onto a bullseye to quantitatively compare PV encirclement. The parameters used to quantify encirclement were varied to perform a sensitivity analysis. Results: Compared to using a complete set of k-space, total atrial scar differences were significant only when sharing >75% k-space (P = 0.014), and 90% sensitivity and specificity for identifying scar was achieved when sharing 50% k-space. In patients, the right PVs showed more intersubject variance in encirclement compared to the left PVs. A 100° anteroinferior portion of the left PVs was always encircled, while the superior segments of both right PVs was ablated in only 6/11 patients. Conclusion: A SharK sequence was developed to combine angiographic and LGE imaging for atrial wall segmentation and scar identification. The PV bullseye quantifies and localizes encirclement about the PVs. The left PVs showed a higher amount of scar encirclement and less variability compared to the right PVs. Level of Evidence: 2. Technical Efficacy: Stage 1. J. Magn. Reson. Imaging 2018;47:477–486.