Retrospective Cohort Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Nov 26, 2016; 8(11): 647-656
Published online Nov 26, 2016. doi: 10.4330/wjc.v8.i11.647
Clinical characteristics and prognostic impact of atrial fibrillation in patients with chronic heart failure
Lorenzo Gigli, Pietro Ameri, Gianmarco Secco, Gabriele De Blasi, Roberta Miceli, Alessandra Lorenzoni, Francesco Torre, Francesco Chiarella, Claudio Brunelli, Marco Canepa
Lorenzo Gigli, Pietro Ameri, Gianmarco Secco, Gabriele De Blasi, Roberta Miceli, Alessandra Lorenzoni, Claudio Brunelli, Marco Canepa, Cardiovascular Disease Unit, Department of Internal Medicine, University of Genova and IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, 16132 Genova, Italy
Francesco Torre, Francesco Chiarella, Cardiology Unit, IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, 16132 Genova, Italy
Author contributions: All authors substantially contributed to this paper; in particular Gigli L, Ameri P and Canepa M conceived and designed the analysis, interpreted the results and drafted the manuscript; Secco G, De Blasi G, Miceli R, Lorenzoni A and Torre F contributed to data acquisition and to the interpretation of results; all authors participated in drafting the article and revised it critically for important intellectual content, read and approved the final manuscript.
Institutional review board statement: The Institutional Review Board (Comitato Etico Regionale della Liguria) evaluated and approved the informed consent sheet for the collection of data for this retrospective analysis.
Informed consent statement: All patients signed an informed consent and approved the utilization of their anonymized clinical information for medical research purposes.
Conflict-of-interest statement: The authors confirm there are no conflicts of interest.
Data sharing statement: Statistical code and dataset are available from the corresponding author at his email address. All data are anonymized and there is no risk of patients’ identification.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Marco Canepa, MD, PhD, Assistant Professor of Cardiology, Cardiovascular Disease Unit, Department of Internal Medicine, University of Genova and IRCCS Azienda Ospedaliera Universitaria San Martino-IST Istituto Nazionale per la Ricerca sul Cancro, Largo Rosanna Benzi, 10, 16132 Genova, Italy. marco.canepa@unige.it
Telephone: +39-010-5555834 Fax: +39-010-5556922
Received: June 29, 2016
Peer-review started: July 1, 2016
First decision: August 5, 2016
Revised: August 26, 2016
Accepted: September 7, 2016
Article in press: September 8, 2016
Published online: November 26, 2016
Processing time: 148 Days and 12.4 Hours
Abstract
AIM

To assess the prevalence, clinical characteristics and independent prognostic impact of atrial fibrillation (AF) in chronic heart failure (CHF) patients, and the potential protective effect of disease-modifying medications, particularly beta-blockers (BB).

METHODS

We retrospectively reviewed the charts of patients referred to our center since January 2004, and collected all clinical information available at their first visit. We assessed mortality to the end of June 2015. We compared patients with and without AF, and assessed the association between AF and all-cause mortality by multivariate Cox regression and Kaplan-Meyer analysis, particularly accounting for ongoing treatment with BB.

RESULTS

A total of 903 patients were evaluated (mean age 68 ± 12 years, 73% male). Prevalence of AF was 19%, ranging from 10% to 28% in patients ≤ 60 and ≥ 77 years, respectively. Besides the older age, patients with AF had more symptoms (New York Heart Association II-III 60% vs 44%), lower prevalence of dyslipidemia (23% vs 37%), coronary artery disease (28% vs 52%) and left bundle branch block (9% vs 16%). On the contrary, they more frequently presented with an idiopathic etiology (50% vs 24%), a history of valve surgery (13% vs 4%) and received overall more devices implantation (31% vs 21%). The use of disease-modifying medications (i.e., BB and ACE inhibitors/angiotensin receptor blockers) was lower in patients with AF (72% vs 80% and 71% vs 79%, respectively), who on the contrary were more frequently treated with symptomatic and antiarrhythmic drugs including diuretics (87% vs 69%) and digoxin (51% vs 11%). At a mean follow-up of about 5 years, all-cause mortality was significantly higher in patients with AF as compared to those in sinus rhythm (SR) (45% vs 34%, P value < 0.05 for all previous comparisons). However, in a multivariate analysis including the main significant predictors of all-cause mortality, the univariate relationship between AF and death (HR = 1.49, 95%CI: 1.15-1.92) became not statistically significant (HR = 0.98, 95%CI: 0.73-1.32). Nonetheless, patients with AF not receiving BB treatment were found to have the worst prognosis, followed by patients with SR not receiving BB therapy and patients with AF receiving BB therapy, who both had similarly worse survival when compared to patients with SR receiving BB therapy.

CONCLUSION

AF was highly prevalent and associated with older age, worse clinical presentation and underutilization of disease-modifying medications such as BB in a population of elderly patients with CHF. AF had no independent impact on mortality, but the underutilization of BB in this group of patients was associated to a worse long-term prognosis.

Keywords: Atrial fibrillation; Chronic heart failure; Beta-blockers; Digoxin; Prognosis

Core tip: In this retrospective analysis atrial fibrillation (AF) was diagnosed in 1 out of 5 patients with chronic heart failure. The arrhythmia was associated with older age, worse clinical presentation and underutilization of disease-modifying medications, particularly beta-blockers (BB) and ACE inhibitors/angiotensin receptor blockers. At a mean follow-up of about 5 years, mortality was significantly higher in patients with AF, and patients with AF not receiving BB treatment were found to have the worst prognosis. However, in a multivariate analysis including main significant predictors of all-cause mortality, such as age, gender, blood pressure, coronary artery disease, comorbidities and medications, the univariate relationship between AF and death became not statistically significant.