4D flow MRI revealed that patients with repaired type A aortic dissection had significantly elevated true lumen reverse flow (P=0.004) and kinetic energy (P=0.0002) compared to controls.
Observational (n=41)
Can 4D flow MRI-derived quantitative hemodynamic maps detect regional flow differences in patients with chronic descending aortic dissection compared to controls?
4D flow MRI-derived parametric hemodynamic maps can quantify regional flow differences in true and false lumens of patients with chronic descending aortic dissection, potentially aiding in risk stratification.
BACKGROUND: Systematic evaluation of complex flow in the true lumen and false lumen (TL, FL) is needed to better understand which patients with chronic descending aortic dissection (DAD) are predisposed to complications. PURPOSE: To develop quantitative hemodynamic maps from 4D flow MRI for evaluating TL and FL flow characteristics. STUDY TYPE: Retrospective. POPULATION: In all, 20 DAD patients (age = 60 ± 11 years; 12 male) (six medically managed type B AD TBAD, 14 repaired type A AD rTAAD now with ascending aortic graft AAo or elephant trunk ET1 repair) and 21 age-matched controls (age = 59 ± 10 years; 13 male) were included. FIELD STRENGTH/SEQUENCE: 1.5T, 3T, 4D flow MRI. ASSESSMENT: 4D flow MRI was acquired in all subjects. Data analysis included 3D segmentation of TL and FL and voxelwise calculation of forward flow, reverse flow, flow stasis, and kinetic energy as quantitative hemodynamics maps. STATISTICAL TESTS: Analysis of variance (ANOVA) or Kruskal-Wallis tests were performed for comparing subject groups. Correlation and Bland-Altman analysis was performed for the interobserver study. RESULTS: Patients with rTAAD presented with elevated TL reverse flow (AAo repair: P = 0.004, ET1: P = 0.018) and increased TL kinetic energy (AAo repair: P = 0.0002, ET1: P = 0.011) compared to controls. In addition, TL kinetic energy was increased vs. patients with TBAD (AAo repair: P = 0.021, ET1: P = 0.048). rTAAD was associated with higher FL kinetic energy and lower FL stasis compared to patients with TBAD (AAo repair: P = 0.002, ET1: P = 0.024 and AAo repair: P = 0.003, ET1: P = 0.048, respectively). DATA CONCLUSION: Quantitative maps from 4D flow MRI demonstrated global and regional hemodynamic differences between DAD patients and controls. Patients with rTAAD vs. TBAD had significantly altered regional TL and FL hemodynamics. These findings indicate the potential of 4D flow MRI-derived hemodynamic maps to help better evaluate patients with DAD. LEVEL OF EVIDENCE: 3 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;51:1357-1368.
Jarvis et al. (Tue,) conducted a observational in Chronic descending aortic dissection (n=41). 4D flow MRI vs. Age-matched controls was evaluated on True lumen and false lumen flow characteristics (forward flow, reverse flow, flow stasis, and kinetic energy). 4D flow MRI revealed that patients with repaired type A aortic dissection had significantly elevated true lumen reverse flow (P=0.004) and kinetic energy (P=0.0002) compared to controls.