Strain analysis in patients with severe aortic stenosis and preserved left ventricular ejection fraction undergoing surgical valve replacement

Abstract

AIMS: To evaluate myocardial multidirectional strain and strain rate (S-and-SR) in severe aortic stenosis (AS) patients with preserved left ventricular (LV) ejection fraction (EF), using two-dimensional speckle-tracking strain imaging (2D-STI). The long-term effect of aortic valve replacement (AVR) on S-and-SR was also evaluated. METHODS AND RESULTS: Changes in LV radial, circumferential, and longitudinal S-and-SR were evaluated in 73 severe AS patients (65 +/- 13 years; aortic valve area 0.8 +/- 0.2 cm2) with preserved LVEF (61 +/- 11%), before and 17 months after AVR. Strain and strain rate data were compared with data from 40 controls (20 healthy individuals and 20 patients with LV hypertrophy) matched by age, gender, body surface area, and LVEF. Compared with controls, severe AS patients had significantly decreased values of LV S-and-SR in the radial (33.1 +/- 14.8%, P = 0.2; 1.7 +/- 0.5 s(-1), P = 0.003), circumferential (-15.2 +/- 5.0%, P = 0.001; -0.9 +/- 0.3 s(-1), P < 0.0001), and longitudinal (-14.6 +/- 4.1%, P < 0.0001; -0.8 +/- 0.2 s(-1), P < 0.0001) directions. At 17 months after AVR, LV S-and-SR significantly improved in all the three directions, whereas LVEF remained unchanged (60 +/- 12%, P = 0.7). CONCLUSION: In severe AS patients, impaired LV S-and-SR existed although LVEF was preserved. After AVR, a significant S-and-SR improvement in all the three directions was observed. These subtle changes in LV contractility can be detected by 2D-STI.