Abnormal left atrial strain predicts worse outcome in dilated cardiomyopathy patients with recovered ejection fraction. A long-term echocardiography study
M Venner, J A J Verdonschot, S L V M Stroeks, C Knackstedt, M T H M Henkens, M A Sikking, M Hoen, M R Hazebroek, A G Raafs, S R B HeymansAbstract
Background
In dilated cardiomyopathy (DCM), 20-30% of patients get heart failure (HF) related events despite full functional recovery (defined as normalisation of left ventricular ejection fraction (LVEF)). Previous studies indicated that abnormal left atrial (LA) or global left ventricular strain (GLS) strain measured by speckle tracking echocardiography (STE), predict worse outcome in DCM. Whether LA strain and GLS predict outcome in DCM/Non-dilated cardiomyopathy (NDLVC) patients with fully recovered EF, remains unknown.
Purpose
This study evaluated the prognostic value of STE strain analysis in NICMP patients with fully recovered EF.
Methods
The prognostic value of echocardiographic LA (reservoir, conduit, and booster) strain and GLS was studied in non-ischemic cardiomyopathy patients (NICMP) with fully recovered LVEF (≥50% and at least (≥) 10 LVEF point increase from disease onset) and available follow-up echocardiogram. NICMP was defined as DCM or NDLVC, based on current guidelines. Primary endpoint composited of cardiac mortality, HF hospitalization or life-threatening arrhythmias. Cubic spline analysis was performed to dichotomize all strain variables. Survival analysis was performed to determine the prognostic value of strain-derived parameters. Likelihood-ratio-test was performed to determine the incremental value of LA strain in the multivariable model.
Results
In 336 NICMP fully recovered patients (median age 58 [50–65] years, 54% male), 38 (11.3%) reached the primary endpoint with a median follow-up of 60 months (IQR: 28-97 months). The cut-off using cubic spline analysis for LV GLS and LA reservoir strain were 17.6% and 34.9%, respectively. LA reservoir strain was a stronger predictor of outcome in fully recovered NICMP patients compared to conduit and booster strain. LA reservoir strain (HR:2.67, 95%-confidence interval [CI]:1.16-6.13, p=0.020), GLS (HR:3.09, 95%-CI:1.12-8.55, p=0.029), LV dilation at disease onset (HR:0.38, 95%-CI:0.19-0.77, p=0.001) and use of loop diuretics at recovery (HR:2.80, 95%-CI:1.39-5.63, p=0.004) remained associated in the multivariable model. At the time of recovery, abnormal LA reservoir strain, whether or not accompanied by abnormal LV GLS, was associated with a significantly worse outcome compared to normal LA reservoir and LV GLS (Kaplan Meier analysis; p-value <0.001). Only 2 events occurred in the group with normal LV and LA strain (n=99) during long-term follow-up.
Conclusion
Echocardiographic LA reservoir strain is an independent predictor of adverse outcome in NICMP patients with fully recovered LVEF. A normal GLS and LA strain predict a near absence of events. Incorporating LA reservoir and GLS strain into the routine evaluation of NICMP patients with fully recovered LVEF may significantly enhance risk stratification, and help to select patients which might benefit of medication withdrawal.central illustrationFor image description, please refer to the figure legend and surrounding text.