Author + information
- Received November 2, 2015
- Revision received January 22, 2016
- Accepted January 28, 2016
- Published online August 1, 2016.
- Mihail G. Chelu, MD, PhDa,∗ (, )
- Bruce D. Gunderson, MSb,
- Jodi Koehler, MSb,
- Paul D. Ziegler, MSb and
- Samuel F. Sears, PhDc
- aCardiovascular Medicine Division, Section of Cardiac Electrophysiology, University of Utah School of Medicine, Salt Lake City, Utah
- bMedtronic, Inc., Minneapolis, Minnesota
- cDepartment of Cardiovascular Sciences, Section of Cardiology, Brody School of Medicine at East Carolina University, Greenville, North Carolina
- ↵∗Reprint requests and correspondence:
Dr. Mihail G. Chelu, Cardiovascular Medicine Division, University of Utah School of Medicine 30 North 1900 East, Room 4A100, Salt Lake City, Utah 84132.
Objectives The study sought to determine the effect of persistent atrial fibrillation (AF) on device-measured activity and mortality.
Background Patients with AF often complain of fatigue, which may be reflected in patient activity. Daily activity can be objectively measured by implanted devices.
Methods We retrospectively studied patients (n = 266, 88% male, 69 ± 10 years of age) from the deidentified Medtronic CareLink database with persistent AF (≥28 consecutive days with ≥23 h of AF/day), dual-chamber implantable cardioverter-defibrillators (ICDs) capable of monitoring daily activity and AF burden, no AF between months 1 and 6 post-implant, and ≥1 year of data.
Results The first persistent AF episode occurred 980 ± 534 days after implant and lasted a median of 87 days (interquartile range: 49 to 161 days). Average daily activity over a week just prior (baseline) to the first persistent AF episode was compared to each of the 4 weeks during the AF episode and to each of the weeks following termination of the persistent AF episode. Daily activity decreased significantly from the baseline week (135 min/day) compared to each of the 4 consecutive weeks after AF onset (8%, 11%, 14%, and 17% decrease, p < 0.001). Mortality at 4 years was increased in patients with persistent AF compared to a matched group with no persistent AF (20.6% vs. 8.6%, p < 0.01).
Conclusions Patients with ICDs have a significant reduction in activity following the onset of persistent AF and a significant increase in mortality when compared to a matched group without persistent AF. Objective measures of activity may more accurately reflect the impact of persistent AF on patients’ functional status.
Mr. Gunderson, Ms. Koehler, and Mr. Ziegler are salaried employees of and own equity interests and stock options in Medtronic, Inc. Dr. Sears has served as a consultant for Medtronic, Inc., and St. Jude Medical; has received research grant support from Medtronic, Inc., and has received honoraria from St. Jude Medical, Medtronic, Inc., Boston Scientific, and Zoll Medical. Dr. Chelu has reported that he has no relationships relevant to the contents of this paper to disclose.
- Received November 2, 2015.
- Revision received January 22, 2016.
- Accepted January 28, 2016.
- American College of Cardiology Foundation