Assessing changes in aortic motion and hemodynamics after valve-sparing aortic root surgery in Marfan syndrome using 4D bSSFP and 4D flow CMR.
Authors
Affiliations (7)
Affiliations (7)
- Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands; Cardiology, Amsterdam University Medical Center, Amsterdam, the Netherlands. Electronic address: [email protected].
- Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands.
- Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, the Netherlands.
- Cardiology, University Medical Center Groningen, Groningen, the Netherlands.
- Cardiology, Amsterdam University Medical Center, Amsterdam, the Netherlands.
- Cardiothoracic surgery, Amsterdam University Medical Center, Amsterdam, the Netherlands.
- Radiology and Nuclear Medicine, Amsterdam University Medical Center, Amsterdam, the Netherlands; Cardiology, Amsterdam University Medical Center, Amsterdam, the Netherlands.
Abstract
Aortic root surgery in patients with Marfan syndrome (MFS) has significantly improved survival, allowing time for distal aortic complications such as type B aortic dissection (TBAD) to emerge. The implantation of a non-compliant synthetic graft may alter aortic biomechanics and hemodynamics, potentially contributing to these late complications. This proof-of-concept study aimed to assess changes in aortic motion and flow characteristics following aortic root surgery using advanced cardiovascular magnetic resonance (CMR) techniques. Three MFS patients (aged 26-37 years), 2 males, one female, undergoing valve-sparing aortic root surgery, were prospectively studied before and six months after surgery. All participants underwent non-contrast-enhanced 4D balanced steady-state free precession and 4D flow CMR at 3T. A deep learning-based segmentation pipeline (nnU-Net) provided segmentations utilized for calculation of aortic displacement, distensibility, regional wall shear stress (WSS) and velocity, and global pulse wave velocity (PWV). Postoperatively, all patients exhibited markedly decreased ascending aortic (AAo) volume. 3D distensibility (10⁻³ mmHg⁻¹) also decreased: patient 1, from 4.1 to 1.7; patient 2, from 3.4 to 1.2; and patient 3, from 2.9 to 1.5. Displacement in the AAo, especially at the sinotubular junction, was substantially reduced, consistent with the rigidity of the implanted graft. In the descending aorta (DAo), distensibility and displacement showed increases in two patients and a decrease in one. Peak systolic velocity and WSS increased in the AAo for all patients, whereas DAo values remained largely unchanged. PWV change varied between patients: decreasing slightly in patient 1, from 8.4 to 7.9m/s, but increased in patients 2 and 3 (8.0 to 8.9m/s and 6.2 to 9.8m/s, respectively. This study demonstrated that AAo biomechanics and hemodynamics change predictably following valve-sparing aortic root surgery in MFS, while changes in the DAo were not consistent between patients. Further research with larger sample sizes is required to identify which of these changes are linked to specific disease profiles and whether parameter combinations can indicate a predisposition to TBAD.