Feature Tracking for Ventricular Strain Assessment in Heart Failure with Preserved Ejection Fraction

Liang Zhong1, Shuang Leng2, Xiaodan Zhao2, Ru-San Tan2
1National Heart Center Singapore, 2National Heart Centre Singapore


Abstract

Impairment of left ventricular (LV) longitudinal function is recognized as an independent predictor of cardiac events in patients with heart failure (HF). Strain imaging derived from speckle tracking echocardiography or feature tracking cardiovascular magnetic resonance (CMR) permit assessments of myocardial function in the longitudinal direction, however, specific competencies and time-consuming protocols are often needed. Therefore, we aim to investigate a fast, semi-automated, and vendor-independent approach for accurate determination of LV longitudinal strain from standard cine CMR images. The LV longitudinal strain parameters are measured using a semi-automatic post-processing algorithm that tracked, on standard two- and four-chamber cine CMR views, the distance (L) between the left atrioventricular junction and apical epicardium (Fig. 1). The atrioventricular junctions are selected as the mitral valve insertion points at the septal and lateral borders of the annulus on the four-chamber view, and the anterior and inferior annular insertion points on the two-chamber view. The strain of each wall at any time point (t) in the cardiac cycle from LV end-diastole (ED, time 0) is calculated based on the strain formula: (L(t)-L(0))×100/L(0). All resulting values from the 4 walls in two- and four-chamber views are averaged to obtain the global longitudinal strain (GLS) and global longitudinal strain rate (GLSR) of the whole LV. The fast GLS assessment was successfully performed in 50 normal controls, and 100 HF patients of which 30 had preserved ejection fraction (HFpEF, LVEF ≥ 50%); 30 had mid-range EF (HFmrEF, LVEF 40 – 49%); and 40 had reduced EF (HFrEF, LVEF < 40%). On multivariate analysis, fast LV GLS was found to be an independent predictor of HFpEF and HFmrEF. The presented fast LV strain measurements represent reliable and expeditiously calculable parameters for quantifying longitudinal LV deformation using routine clinical cine CMR images.