Author + information
- Received December 23, 2018
- Revision received March 18, 2019
- Accepted March 18, 2019
- Published online May 1, 2019.
- Hariharan Sugumar, MBBSa,b,c,d,∗,
- Peter M. Kistler, MBBS, PhDa,b,d,∗∗ (, )
- Sandeep Prabhu, MBBSa,b,c,d,∗,
- Aleksandr Voskoboinik, MBBSa,b,c,d,
- Shane Young, MAScb,
- Sarah J. Gutman, MBBSa,b,e,
- Geoffrey R. Wong, MBBSc,d,
- Ramanathan Parameswaran, MBBSc,d,
- Chrishan J. Nalliah, MBBSc,d,
- Geoff Lee, MBChB, PhDa,d,
- Alex J. McLellan, MBBS, PhDa,b,c,d,
- Andrew J. Taylor, PhDa,b,e,
- Liang-Han Ling, MBBS, PhDa,b,d and
- Jonathan M. Kalman, MBBS, PhDc,d
- aBaker Heart and Diabetes Institute, Melbourne, Victoria, Australia
- bThe Alfred Hospital, Melbourne, Victoria, Australia
- cRoyal Melbourne Hospital, Melbourne, Victoria, Australia
- dUniversity of Melbourne, Melbourne, Victoria, Australia
- eMonash University, Melbourne, Victoria, Australia
- ↵∗Address for correspondence:
Prof. Peter Kistler, Heart Centre, The Alfred Hospital, Commercial Road, Melbourne, Victoria 3004, Australia.
Objectives This study sought to determine the long-term right atrial (RA) electrical and structural changes in a subgroup from the CAMERA-MRI (Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction - Magnetic Resonance Imaging) study.
Background Catheter ablation (CA) is successful in restoring ventricular function in patients with atrial fibrillation (AF) and otherwise unexplained cardiomyopathy, as demonstrated in the randomized study of CA versus rate control (CAMERA-MRI [(Catheter Ablation Versus Medical Rate Control in Atrial Fibrillation and Systolic Dysfunction−Magnetic Resonance Imaging]). It is unknown if this is associated with atrial remodeling.
Methods Detailed electroanatomical (EA) mapping of the RA using CARTO3 and a force sensing catheter was performed at initial CA and electively at least 12 months after CA in patients with >90% reduction in AF burden following ablation. Bipolar voltage, fractionation, and conduction velocity were collected in 4 segments together with echo and cardiac magnetic resonance imaging.
Results Fifteen patients (mean age 59.1 ± 6.8 years) underwent repeat RA EA mapping. At a mean follow-up of 23.4 ± 11.9 months, left ventricular (LV) ejection fraction improved from 33.6 ± 3.2% to 54.1 ± 3.2% (p = 0.001), RA area decreased from 28.4 ± 2.0 to 20.8 ± 1.2 cm2 (p < 0.001), and left atrial area decreased from 32.9 ± 2.3 to 26.8 ± 1.4 cm2 (p = 0.007). On EA mapping, RA bipolar voltage increased from 1.6 ± 0.1 to 1.9 ± 0.1 mV (p = 0.04). Tissue voltage increased across all regions, which achieved statistical significance at the posterior (p = 0.002) and septal (p = 0.01) segments. There was a significant decrease in complex fractionated electrograms from 21.7 ± 3.5% to 8.3 ± 1.8% (p = 0.002); however, no significant change occurred in global or regional conduction velocities (p = 0.5).
Conclusions Recovery of atrial electrical and structural changes was observed following restoration of sinus rhythm and recovery of LV function in patients who underwent CA for persistent AF and LV systolic dysfunction. The randomized CAMERA MRI study demonstrated significant improvement in LV systolic function with AF ablation compared with rate control. The present study demonstrated reverse electrical and structural atrial recovery in concert with recovery of LV systolic function at 2 years post-AF ablation. This may partially explain the long-term success of CA in patients with AF and otherwise unexplained cardiomyopathy.
↵∗ Drs. Sugumar, Kistler, and Prabhu contributed equally to this work and are joint first authors.
Drs. Sugumar, Prabhu, Voskoboinik and Ling received funding from Australian National Health and Medical Research Council (NHMRC) and/or National Heart Foundation of Australia. Dr. Sugumar received funding from Royal Australasian College of Physicians and Centre of Research Excellence in Cardiovascular Outcomes Improvement (CRECOI). Andrew Epstein, MD, served as Guest Editor for this paper. Dr. Sugumar has received fellowship support from St Jude Medical and Medtronic. Dr. Prabhu has received fellowship funding from Abbott, Boston Scientific, Biosense Webster, the Heart Foundation, and EHRA. Dr. Ling has received fellowship support from Medtronic, Biotronik and St Jude Medical. Prof. Kalman has received research and fellowship support from St Jude Medical, Medtronic, Biosense Webster, Boston Scientific and Abbott and has received consultancy fees from Biosense Webster. Prof. Kistler has received consultancy and speaking engagement fees from St Jude Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received December 23, 2018.
- Revision received March 18, 2019.
- Accepted March 18, 2019.
- 2019 American College of Cardiology Foundation
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