Background:

The left atrium (LA) plays an important role in modulating left ventricular filling. Thus, left atrial strain analysis has emerged as a potential marker with prognostic relevance for several pathologies of the left ventricle such as heart failure. 2D strain imaging of the LA is a reliable method that allows determination of contractile, conduit and reservoir functions separately. Patients that present with reduced left ventricular ejection fraction (LVEF) and recover after guideline-directed medical therapy represent a distinct entity of heart failure patients (HFrecEF).

Aim:

To retrospectively analyze LA strain in patients that presented to our clinic with newly diagnosed reduced LVEF and sinus rhythm of non-ischemic aetiology to determine if LA function can predict LVEF recovery by medical therapy.

Methods:

We retrospectively analyzed 2D echocardiographic data from 73 patients by two-dimensional speckle tracking using dedicated software (Image-Arena™ Version 4.6; TomTec Imaging Systems) at the time of diagnosis and after about 4 months (median: 125 days). The R-gated method using ventricular end diastole as zero reference point was used. We obtained LA reservoir strain (LASr), LA conduit strain (LAScd) and LA contraction strain (LASct) as well as LV and RV parameters. As proposed in 2020 we classified a patient as HFrecEF if an improvement in LVEF of 10% or more to a value above 40% was present. Differences between groups were evaluated using Mann-Whitney-U-test. ROC analysis was performed to estimate the predictive power.

Results:

Out of 73 studies, 14 were excluded due to poor image quality. HFrecEF occurred in 28 out of 59 patients (47%). Patient characteristics at both time points are presented in Table 1 and did not reveal significant differences in baseline characteristics despite in the HFrecEF group left ventricular diameters were slightly smaller. At initial TTE on average LASr and LAScd was higher in the HFrecEF group (13,9% vs 10,0; p<0,05 and 8,8% vs. 5,5%;p:0,05), whereas LASct showed no significant differences (4,2% vs. 3,7%; p:0,56). After guideline directed medical therapy, LA strain values improved for both groups but ΔLASr (15,8%vs.5,4%; p<0,05) and ΔLAScd (9,2% vs. 1,9%, p<0,05) was greater in HFrecEF. ROC analysis however revealed only moderate results with an area under the curve of 0,678 for LASr, 0,716 for LAScd and 0,559 for LASct for prediction of LVEF recovery (Figure 1).

Conclusion:

Our data suggest that patients with high potential for LVEF recovery show higher initial and sequential LA strain. Even though associated with several limitations, obtaining LA strain at the time of diagnosis of heart failure with reduced LVEF might be useful in predicting LVEF recovery potential. 

Parameter	HFrecEF	HFrEF	p
Age in years	48,9±11,4	51,5±14	0,37
% female	35,7	32,2	0,78
BSA in m²	1,93±0,27	1,90±0,28	0,56
BMI in kg/m²	27,0±5,8	25,7±5,0	0,25
BNP in pg/ml	1233±842	1322±1067	0,96
eGFR in ml/min	83,1±23,5	78,3±19,4	0,11
Bilirubin in µmol/l	17,7±11,8	16,7±11,8	0,83
LVEF in %	26,0±5,5	23,5±5,9	0,06
LVEDV in ml	208±67	226±73	0,28
LVEDd in mm	63±7	67±9	0,02
RVEDd in mm	41±8	41±7	0,85
TAPSE in mm	14±4	15±4	0,37
TR-PPG in mmHg	33±10	32±13	0,45
E/A ratio	2,3	2,1	0,48
E/e´ ratio	20	20	0,39
LA volume index in ml/m²	52,1±18,5	57,0±17,2	0,12

Table 1.Baseline characteristics

 Figure 1. Receiver operating characteristic for LASr, LAScd and LASct