Qualitative and Quantitative Assessments of Blood Flow on Tears in Type B Aortic Dissection With Different Morphologies

Saitta, Simone; Guo, Baolei; Pirola, Selene; Menichini, Claudia; Guo, Daqiao; Shan, Yan; Dong, Zhihui; Xu, Xiao Yun; Fu, Weiguo

doi:10.3389/fbioe.2021.742985

Cited by 8 publications

(3 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The velocity encoded MR images were post processed using a previously developed ( 19 ) open source Python code, 1 that allows the creation of flow maps, which are stored in a.vtk-file for each measurement. Continuous flow results were voxel-wise averaged over three consecutive measurements to improve the signal-to-noise ratio.…”

Section: Methodsmentioning

confidence: 99%

Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

Aigner

Bart

Panfili

et al. 2023

Front. Cardiovasc. Med.

Self Cite

View full text Add to dashboard Cite

IntroductionTranscatheter aortic valve implantation (TAVI) has become an alternative to surgical replacement of the aortic valve elderly patients. However, TAVI patients may suffer from paravalvular leaks (PVL). Detecting and grading is usually done by echocardiography, but is limited by resolution, 2D visualization and operator dependency. 4D flow magnetic resonance imaging (MRI) is a promising alternative, which did not reach clinical application in TAVI patients. The aim of this study was applying 3D printing technologies in order to evaluate flow patterns and hemodynamics of PVLs following TAVI, exploiting 4D flow MRI and standard ultrasound.Materials and methodsAn MR-compatible, anatomically left ventricle, aortic root, and ascending aorta model was fabricated by combining 3D-printed parts and various soft silicone materials to match physiological characteristics. An Abbott Portico™ valve was used in continuous antegrade flow (12–22 l/min), retrograde flow with varying transvalvular pressures (60–110 mmHg), and physiological pulsatile hemodynamics (aortic pressure: 120/80 mmHg, cardiac output: 5 l/min) Time-resolved MR measurements were performed above and below the TAVI stent and compared with color Doppler ultrasound measurements in exactly the same setup.ResultsThe continuous antegrade flow measurements from MRI largely agreed with the flowmeter measurements, and a maximum error of only 7% was observed. In the retrograde configuration, visualization of the paravalvular leaks was possible from the MR measurements, but flow was overestimated by up to 33%. The 4D MRI measurement in the pulsatile setup revealed a single main PVL, which was also confirmed by the color Doppler measurements, and velocities were similar (2.0 m/s vs. 1.7 m/s).Discussion4D MRI techniques were used to qualitatively assess flow in a patient-specific, MR-compatible and flexible model, which only became possible through the use of 3D printing techniques. Flow patterns in the ascending aorta, identification and quantification of PVLs was possible and the location and extent of PVLs were confirmed by ultrasound measurements. The 4D MRI flow technique allowed evaluation of flow patterns in the ascending aorta and the left ventricle below the TAVI stent with good results in identifying PVLs, demonstrating its capabilities over ultrasound by providing the ability to visualize the paravalvular jets in three dimensions at however, additional expenditure of time and money.

show abstract

Section: Methodsmentioning

confidence: 99%

Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

Aigner

Bart

Panfili

et al. 2023

Front. Cardiovasc. Med.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Overall, several studies have been published regarding 4D flow MRI in TBAD patients, yet each of them lacks long-term follow-up and an appropriate number of cases. [12][13][14][15][16] Apparently, 4D flow MRI seems comparable to triphasic CTA in terms of fenestration detection in TBAD patients based on the study conducted by Allen et al 12 Another study concluded that 4D flow MRI image quality is comparable to CTA for TBAD assessment. 13 A third paper evaluated false lumen pressure analysis in chronic TBAD patients and identified false lumen ejection fraction and absolute pressure difference between distal false lumen and aortic root as independent factors for aortic growth.…”

Section: Type-b Aortic Dissectionmentioning

confidence: 99%

Dynamic Imaging of Aortic Pathologies: Review of Clinical Applications and Imaging Protocols

Osztrogonacz¹,

Berczeli

Chinnadurai

et al. 2023

Methodist DeBakey Cardiovascular Journal

View full text Add to dashboard Cite

The past decade has seen significant advances in dynamic imaging of the aorta. Today's vascular surgeons have the opportunity to choose from a wide array of imaging modalities to evaluate different aortic pathologies. While vascular ultrasound and aortography are considered to be the bread and butter imaging modalities, newer dynamic imaging techniques provide time-resolved information in various aortic pathologies. However, despite growing evidence of their advantages in the literature, they have not been routinely adopted. In order to understand the role of these emerging modalities, one must understand their principles, advantages, and limitations in the context of various clinical scenarios. In this review, we provide an overview of dynamic imaging techniques for aortic pathologies and describe various dynamic computed tomography and magnetic resonance imaging protocols, clinical applications, and potential future directions.

show abstract

“…Retrograde flow index (RFI) was calculated as the fraction of negative area under the curve of the flow rate time-course over the whole area under the curve [25]:…”

Section: Flow Morphology Descriptorsmentioning

confidence: 99%

Data-driven generation of 4D velocity profiles in the aneurysmal ascending aorta

Saitta¹,

Maga²,

Armour³

et al. 2022

Preprint

View full text Add to dashboard Cite

Background and Objective: Numerical simulations of blood flow are a valuable tool to investigate the pathophysiology of ascending thoratic aortic aneurysms (ATAA). To accurately reproduce in vivo hemodynamics, computational fluid dynamics (CFD) models must employ realistic inflow boundary conditions (BCs). However, the limited availability of in vivo velocity measurements, still makes researchers resort to idealized BCs. The aim of this study was to generate and thoroughly characterize a large dataset of synthetic 4D aortic velocity profiles with features similar to clinical cohorts of patients with ATAA. Methods: Time-resolved 3D phase contrast magnetic resonance (4D flow MRI) scans of 30 subjects with ATAA were processed through in-house code to extract anatomically consistent cross-sectional planes along the ascending aorta, ensuring spatial alignment among all planes and interpolating all velocity fields to a reference configuration. Velocity profiles of the clinical cohort were extensively characterized by computing flow morphology descriptors of both spatial and temporal features.

show abstract

Qualitative and Quantitative Assessments of Blood Flow on Tears in Type B Aortic Dissection With Different Morphologies

Cited by 8 publications

References 32 publications

Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

Quantification of paravalvular leaks associated with TAVI implants using 4D MRI in an aortic root phantom made possible by the use of 3D printing

Dynamic Imaging of Aortic Pathologies: Review of Clinical Applications and Imaging Protocols

Data-driven generation of 4D velocity profiles in the aneurysmal ascending aorta

Contact Info

Product

Resources

About