Abstract 18650: Impact of Severity of Aortic Stenosis on Left Ventricular Apical Rotation

Abstract

Introduction- Two dimensional speckle tracking echocardiography is a novel non-invasive method to assess subtle changes in left ventricular (LV) function such as strain and rotational dynamics. Limited data exists for assessing the impact of severity of aortic stenosis (AS) on LV apical rotation

Objective- To determine the impact of severity of AS on LV longitudinal strain as well as LV apical rotation in patients with preserved LV ejection fraction and various degrees of AS.

Methods-We prospectively measured longitudinal LV strain and apical rotation in 74patients with preserved LV ejection fraction but no (n= 22), mild (MG 10-25 mmHg; n= 20), moderate (MG 25-40 mmHg; n= 18), or severe (MG >40 mmHg; n= 14) AS who were undergoing echocardiographic examination at our institution. Two dimensional speckle tracking method was used to obtain average peak longitudinal strain using apical 4, 2-chamber and long-axis views while apical short axis view was used to obtain the LV apical rotation.

Results- Mean age between no vs. mild vs. mod vs. severe AS groups (73±11yrs; 70±13yrs; 77±6yrs; 76±14 yrs) was not different (p=0.26). Presence of hypertension (64%, 65%, 78%, 71%) and coronary artery disease (14%, 6%, 25%, 29%) were also not different between the groups (p = 0.76 and p = 0.23 respectively). Average LV peak global longitudinal strain was not different between groups (-17.5±3%; -17.5±5%;-16.6±4%; -16.6±3% (p=0.82). However LV peak apical rotation was higher with worsening severity of aortic stenosis (14.8±8°; 14.7±9°; 21.3±11°; 23.7±12°) (overall p=0.02) (Figure).

Conclusions- 1) LV peak longitudinal strain was not different between patients with no stenosis when compared to patients with various levels of aortic stenosis. 2) However, LV apical rotation increases with worsening levels of AS probably to maintain the LV stroke volume. Further studies are needed to evaluate the role of LV apical rotation in deciding the timing of surgery in patients with severe AS.