Atrial Fibrillation in Heart Failure With Preserved Ejection Fraction: Association With Exercise Capacity, Left Ventricular Filling Pressures, Natriuretic Peptides, and Left Atrial Volume.

Lam CS, Rienstra M, Tay WT, Liu LC, Hummel YM, van der Meer P,
de Boer RA, Van Gelder IC, van Veldhuisen DJ, Voors AA, Hoendermis

JACC Heart Fail. 2017 Feb;5(2):92-98. doi: 10.1016/j.jchf.2016.10.005. Epub 2016
Dec 21.

OBJECTIVES: This study sought to study the association of atrial fibrillation
(AF) with exercise capacity, left ventricular filling pressure, natriuretic
peptides, and left atrial size in heart failure with preserved ejection fraction
BACKGROUND: The diagnosis of HFpEF in patients with AF remains a challenge
because both contribute to impaired exercise capacity, and increased natriuretic
peptides and left atrial volume.
METHODS: We studied 94 patients with symptomatic heart failure and left
ventricular ejection fractions ≥45% using treadmill cardiopulmonary exercise
testing and right- and/or left-sided cardiac catheterization with simultaneous
RESULTS: During catheterization, 62 patients were in sinus rhythm, and 32
patients had AF. There were no significant differences in age, sex, body size,
comorbidities, or medications between groups; however, patients with AF had lower
peak oxygen consumption (VO2) compared with those with sinus rhythm (10.8 ± 3.1
ml/min/kg vs. 13.5 ± 3.8 ml/min/kg; p = 0.002). Median (25th to 75th percentile)
N-terminal pro-B-type natriuretic peptide (NT-proBNP) was higher in AF versus
sinus rhythm (1,689; 851 to 2,637 pg/ml vs. 490; 272 to 1,019 pg/ml; p < 0.0001).
Left atrial volume index (LAVI) was higher in AF than sinus rhythm (57.8 ± 17.0
ml/m2 vs. 42.5 ± 15.1 ml/m2; p = 0.001). Invasive hemodynamics showed higher mean
pulmonary capillary wedge pressure (PCWP) (19.9 ± 3.7 vs. 15.2 ± 6.8) in AF
versus sinus rhythm (all p < 0.001), with a trend toward higher left ventricular
end-diastolic pressure (17.7 ± 3.0 mm Hg vs. 15.7 ± 6.9 mm Hg; p = 0.06). After
adjusting for clinical covariates and mean PCWP, AF remained associated with
reduced peak VO2 increased log NT-proBNP, and enlarged LAVI (all p ≤0.005).
CONCLUSIONS: AF is independently associated with greater exertional intolerance,
natriuretic peptide elevation, and left atrial remodeling in HFpEF. These data
support the application of different thresholds of NT-proBNP and LAVI for the
diagnosis of HFpEF in the presence of AF versus the absence of AF.