Abstract
Background Transcatheter aortic valve implantation (TAVI) is a new method for treating patients with severe aortic stenosis with high risk for or rejected from conventional heart surgery. Its impact on blood flow patterns and parameters in the ascending aorta are unknown. Using 4-dimensional phase contrast MRI (4D Flow MRI) we examined the hemodynamics in the ascending aorta after TAVI and compared them to stented bioprostheses and healthy controls. Methods We used 4D Flow MRI (spatial resolution 1.8x1.8x2.5mm3; temporal resolution 13-22 phases/heart cycle) of the ascending aorta in 14 patients with TAVI (mean age 76 years, 8 males, all Edwards Sapien), 12 patients with different stented bioprostheses (mean age 77 years, 8 males) and 9 healthy controls (mean age 55 years, 8 males) controls using a 1.5T MR system. We examined the distribution of the maximum systolic wall shear stresses as well as the maximum blood flow velocities in the mid-ascending aorta. Results Patients with TAVI and stented bioprosthesis revealed an asymetric distribution of the wall shear stresses with significantly elevated values at the anterior and right-anterior curvature and significantly lower values at the posterior curvature compared to the healthy controls. Concerning the maximum velocities both TAVI and stented bioprostheses revealed an asymetric distribution along the right-anterior curvature where TAVI showed a more anterior distribution compared to the healty controls which showed a central distribution. Conclusion The blood flow patterns in patients with TAVI and stented bioprostheses differs significantly from the ones in healthy controls. However, TAVI and stented bioprosthesis showed small but significant regional differences.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.