Effects of transcatheter aortic valve implantation on ascending aorta wall elastic properties: Tissue Doppler imaging and strain Doppler echocardiography study.

BACKGROUND

Aortic elastic properties are determinants of left ventricular function by means of ventriculo-arterial coupling and indicators of cardiovascular risk. Aortic valve stenosis surgical replacement temporary reduces aortic function damaging vasa vasorum, while transcatheter aortic valve implantation (TAVI) does not influence it in the short term. We studied aortic distensibility, stiffness, M-mode strain and tissue strain after 6 and 12 months from TAVI.

METHODS

We enrolled 15 patients with symptomatic severe aortic stenosis who underwent CoreValve prosthesis (Medtronic, Minneapolis, MN) implantation. Everyone had blood pressure measurement and echocardiography registration before TAVI and after 6 and 12 months.

RESULTS

After TAVI NYHA class (p = 0.016), peak and mean aortic valve gradients (p < 0.001 for both) improved. Aortic distensibility increased (p = 0.032 in the first 6 months, p = 0.005 in the second 6 months, and p = 0.003 from baseline to 12 months), as well as stiffness decreased (p = 0.034; 0.090; 0.001), M-mode strain and tissue strain ameliorated (p = 0.041; 0.004; 0.004; and p = 0.013; 0.002; 0.001, respectively), tissue Doppler imaging improved (S' wave: p = 0.289; 0.347; 0.018. E' wave: p = 0.018; 0.113; 0.007. A' wave: p = 0.002; 0.532; 0.001). Moreover, some left ventricular parameters improved at 6 months, such as ejection fraction (from 49 ± 16 to 57 ± 11%; p = 0.044) and diastolic interventricular septum thickness (from 14 ± 2 to 12 ± 2 mm; p = 0.010). Even systolic pulmonary artery pressure (p = 0.019) and left diastolic dysfunction grade ameliorated (p = 0.042).

CONCLUSIONS

For the first time we demonstrated that aortic elastic properties improve at 6 and 12 months after TAVI, thus influencing ventriculo-arterial coupling and ameliorating left ventricular function.