Short term improvement of global left ventricular longitudinal strain by speckle tracking echocardiography after transcatheter aortic valve implantation in patients with severe aortic stenosis
Authors: Nosir Y , Nosir M.Y.F , Al-Shaibi A.K , Petilla M , Alasnag M , Waqar A , Al-Shaibi K 
Published: November 2020

Abstract

Background
Global longitudinal strain (GLS) has incremental value in assessing left ventricular (LV) function in patients with severe aortic stenosis (AS). Long-standing AS causes LV hypertrophy which predisposes to increased cardiac morbidity and mortality. The recent development of transcatheter aortic valve implantation (TAVI) device for treatment of severe symptomatic AS, offers an option for high risk patients.

Objectives
Our aim was to investigate the correlation between the time elapsed after performing a TAVI procedure and the LV GLS by Speckle tracking echocardiography (STE) and its correlation with progressive degree of regression in LV mass (LVM) by transthoracic echocardiography (TTE).

Methods
TTE was performed on 54 patients with severe AS who underwent TAVI procedure. TTE was performed at baseline (before the procedure) and then at 3 months and 6 months post TAVI. GLS was calculated for every patient from STE of the three apical views (apical 4, apical 2 and apical long axis views). The LV muscle volume was calculated by subtraction of LV pericardial volume from LV endocardial volume using biplane Simpson's formula. LVM was then calculated by multiplying LV mass volume by muscle density (1.05).

Results
The study included 54 patients with severe AS (average PG =79.5 mmHg and average mean gradient 40.5 mmHg), with a mean age of 79±10 years and 46 were male. All patients underwent TAVI and average mean gradient post TAVI was 7 mmHg. The mean ± SD of GLS were −15.3±2.0, −15.9±1.7 and −17.2±1.8 for STE obtained at baseline, 3- and 6-months post TAVI, respectively. There was significant difference in LV GLS when comparing baseline measurements with measurements obtained at both 3 months {mean difference ± SD (MD±SD) was 0.57±0.7 (p&lt;0.001)} and at 6 months post TAVI was 1.8±0.8 (p&lt;0.0001). There was significant difference when comparing LV GLS measurements at 3- and 6- months post TAVI MD±SD was 1.2±0.65 (p&lt;0.001). The mean±SD of LVM was 118.5±31, 110.5±29.2 and 101.1±26.4 at baseline, 3- and 6-months post TAVI, respectively. There was significant difference between baseline and 3 months measurement of LVM, MD±SD is 7.6±6.0 (p&lt;0.001). There was significant difference between baseline and 6 months measurement of LVM, MD±SD was 17.0±10.5 (p&lt;0.0001). In addition, there was significant difference of LVM calculation at 3 and 6 months with MD±SD of 9.4±7.9 and (P&lt;0.001).

Conclusions
In patient with severe AS that underwent TAVI, there is short term continues significant improvement of LV GLS by STE. This could be attributed to relieving the pressure overload and regression of LVM over time. Decreasing LV hypertrophy and increasing LV GLS on the short term indicate high efficacy of TAVI procedure and subsequently improving patient prognosis and quality of life.

Funding Acknowledgement
Type of funding source: None