Open AccessBoth beat-to-beat changes in RR-interval and left ventricular filling time determine ventricular function during atrial fibrillation
Author(s) -
Aurore Lyon,
Manouk van Mourik,
Laura Cruts,
Jordi Heijman,
Sebastiaan C.A.M. Bekkers,
Ulrich Schotten,
Harry J.G.M. Crijns,
Dominik Linz,
Joost Lumens
Publication year - 2021
Publication title -
europace
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.119
H-Index - 102
eISSN - 1532-2092
pISSN - 1099-5129
DOI - 10.1093/europace/euaa387
Subject(s) - preload , cardiology , medicine , beat (acoustics) , atrial fibrillation , diastole , rr interval , speckle tracking echocardiography , hemodynamics , heart rate , heart failure , blood pressure , ejection fraction , heart rate variability , physics , acoustics
Aims The irregular atrial electrical activity during atrial fibrillation (AF) is associated with a variable left ventricular (LV) systolic function. The mechanisms determining LV function during AF remain incompletely understood. We aimed at elucidating how changes in RR-interval and LV preload affect LV function during AF. Methods and results Beat-to-beat speckle-tracking echocardiography was performed in 10 persistent AF patients. We evaluated the relation between longitudinal LV peak strain and preceding RR-interval during AF. We used the CircAdapt computational model to evaluate beat-to-beat preload and peak strain during AF for each patient by imposing the patient-specific RR-interval sequences and a non-contractile atrial myocardium. Generic simulations with artificial RR-interval sequences quantified the haemodynamic changes induced by sudden irregular beats. Clinical data and simulations both showed a larger sensitivity of peak strain to changes in preceding RR-interval at slow heart rate (HR) (cycle length, CL <750 ms) than at faster HR. Simulations explained this by a difference in preload of the current beat. Generic simulations confirmed a larger sensitivity of peak strain to preceding RR-interval at fast HR (CL = 600 ms: Δ peak strain = 3.7% vs. 900 ms: Δ peak strain = 0.3%) as in the patients. They suggested that longer LV activation with respect to preceding RR-interval is determinant for this sensitivity. Conclusions During AF, longitudinal LV peak strain is highly variable, particularly at fast HR. Beat-to-beat changes in preload explain the differences in LV systolic function. Simulations revealed that a reduced diastolic LV filling time can explain the increased variability at fast HR.