How to Detect the Early Cardiac Functional Change and Predict Heart Failure in Paroxysmal Atrial Fibrillation? A Prospective Cohort Study

Backgrounds20-30% atrial fibrillation (AF) may result in heart failure (HF). Noninvasive left ventricle myocardial work (LVMW) is a fairly new method for detecting LV function. We aimed to evaluate whether LVMW could detect the LV change function in paroxysmal atrial fibrillation (PAF) and predict HF incident. MethodsIn this prospective cohort study, 146 PAF subjects and 63 non-PAF subjects matched by age and gender set as the controls were enrolled. Noninvasive LVMW parameters, including global work index, global constructive work, global wasted work (GWW) and global work efficiency (GWE) were obtained from LV pressure-strain loop by 2D speckle tracking imaging. LA volume index (LAVI) was measured by 3D echocardiography. AF burden (AFB) was evaluated by questionnaire. The primary outcome was the incident HF.AFB deterioration was evaluated at the end of follow up. Stata15.0 and R4.1 were used for data analysis and description. ResultsThe average age was 66.2{+/-}11.4 years and comprised 55% males in PAF. Compared with the controls, PAF had significantly elevated GWW (143.7{+/-}88.3mmHg% vs 115.5{+/-}59.6mmHg%, p<0.001) and impaired GWE (92.3{+/-}7.5% vs 93.8{+/-}2.8%, p=0.035) and they were correlated with increased LAVImax and LAVImin. Those with higher AFB showed significantly decreased LAEF and increased LAVImin. During the average 40.5 months follow-up, 9.9% PAF developed HF and ablation reduced the HF occurrence. In the non-ablation subgroup, baseline decreased LAEF rather than LVMW was a strong predictor for HF. As expected, AFB deterioration was strongly associated with HF incident. ConclusionsElevated GWW was detected by LVMW and it was strongly correlated with LA dilation in PAF. Higher AFB had adverse effect on LAVImin. Restoring sinus rhythm was significant for HF prevention, especially for PAF with lower LAEF. Clinical PerspectiveO_ST_ABSWhat is new?C_ST_ABSO_LIAlthough GLS and LVEF remained normal, subtle LV dysfunction of elevated GWW and impaired GWE could be detected by LVMW in the early stage of PAF. C_LIO_LIIncreased LAVImin, rather than LAEF, was strongly associated with elevated GWW and higher AF burden in PAF. C_LIO_LIRestoring sinus rhythm was important to early stage of PAF for HF prevention, especially in PAF with lower LAEF. C_LI What are the clinical implications?O_LIIt is significant for PAF to protect LV function by maintaining sinus rhythm or keeping AFB at minimal-mild stage, even from the very early stage. C_LIO_LIIncreased LAVImin is an important indicator for detecting LV dysfunction in PAF and the underlying mechanism needs to be discovered. C_LI