Sherene Shalhub1, Michal Schäfer2, Thomas S Hatsukami3, Matthew P Sweet3, Jason J Reynolds3, Ferdia A Bolster4, Susanna H Shin3, T Brett Reece5, Niten Singh3, Benjamin W Starnes3, Omid Jazaeri6. 1. Division of Vascular Surgery, Department of Surgery, University of Washington, Seattle, Wash. Electronic address: shalhub@uw.edu. 2. Department of Cardiology, Children's Hospital Colorado, Aurora, Colo. 3. Division of Vascular Surgery, Department of Surgery, University of Washington, Seattle, Wash. 4. Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland. 5. School of Medicine, Division of Cardiothoracic Surgery, Department of Surgery, University of Colorado Denver, Aurora, Colo. 6. School of Medicine, Division of Vascular Surgery and Endovascular Therapy, Department of Surgery, University of Colorado Denver, Aurora, Colo.
Abstract
OBJECTIVE: Congenital aortic arch variations are more common in patients with thoracic aortic disease for reasons unknown. Additionally, little is understood about their relation to type B aortic dissections (TBAD) specifically. We investigated the prevalence of variant aortic arch anatomy in patients with TBAD compared with controls. To understand the implications of how variant aortic arch anatomy may contribute to degenerative aortic disease, we compared flow hemodynamics of three variations of aortic arches using four-dimensional flow magnetic resonance imaging (4D flow MRI). METHODS: Arch anatomy on computed tomography imaging was reviewed and compared between patients with TBAD and age/sex-matched controls free of aortic pathology. Arch variants were defined as follows: common origin of innominate and left common carotid artery (bovine arch), aberrant right subclavian artery, and right-sided aortic arch. Demographics, TBAD characteristics, and follow-up data were abstracted. Patients with TBAD with variant and conventional aortic arches were compared. Additionally, three matched healthy controls with conventional, bovine, and aberrant right subclavian artery arches underwent 4D flow MRI evaluation to assess if there were differences in flow patterns by arch type. Indices of regional hemodynamic wall sheer stress were compared. RESULTS: Computed tomography scans of 185 patients with TBAD (mean age, 58.1 ± 12.4 years; 72.4% males; 71.4% Caucasian) and 367 controls (mean age, 62.5 ± 13.4 years; 67% males; 77.9% Caucasian) were reviewed. Variant arch anatomy was more prevalent in patients with TBAD (40.5% vs 24.5%; P < .001). In patients with TBAD, there were no differences in the mean age of presentation and descending thoracic aorta diameter among those with variant or conventional arch anatomy. Patients with TBAD with variant arch anatomy had a higher percentage of dissection related thoracic aortic repairs (54.7% vs 33.6%; P = .004) with repairs occurring predominantly in the acute phase. 4D flow MRI demonstrated a higher systolic wall shear stress along the inner curve of the bovine arch compared with the conventional aberrant right subclavian artery arches. CONCLUSIONS: Variant aortic arch anatomy is significantly more prevalent in patients with TBAD. patients with TBAD with variant arch anatomy had a higher percentage of dissection-related aortic repair. Preliminary 4D flow MRI data show differences in hemodynamic flow patterns between variant and conventional arches. Studies of long-term outcomes based on arch anatomy may offer additional insight to TBAD genesis and possibly influence management decisions.
OBJECTIVE:Congenital aortic arch variations are more common in patients with thoracic aortic disease for reasons unknown. Additionally, little is understood about their relation to type B aortic dissections (TBAD) specifically. We investigated the prevalence of variant aortic arch anatomy in patients with TBAD compared with controls. To understand the implications of how variant aortic arch anatomy may contribute to degenerative aortic disease, we compared flow hemodynamics of three variations of aortic arches using four-dimensional flow magnetic resonance imaging (4D flow MRI). METHODS: Arch anatomy on computed tomography imaging was reviewed and compared between patients with TBAD and age/sex-matched controls free of aortic pathology. Arch variants were defined as follows: common origin of innominate and left common carotid artery (bovine arch), aberrant right subclavian artery, and right-sided aortic arch. Demographics, TBAD characteristics, and follow-up data were abstracted. Patients with TBAD with variant and conventional aortic arches were compared. Additionally, three matched healthy controls with conventional, bovine, and aberrant right subclavian artery arches underwent 4D flow MRI evaluation to assess if there were differences in flow patterns by arch type. Indices of regional hemodynamic wall sheer stress were compared. RESULTS: Computed tomography scans of 185 patients with TBAD (mean age, 58.1 ± 12.4 years; 72.4% males; 71.4% Caucasian) and 367 controls (mean age, 62.5 ± 13.4 years; 67% males; 77.9% Caucasian) were reviewed. Variant arch anatomy was more prevalent in patients with TBAD (40.5% vs 24.5%; P < .001). In patients with TBAD, there were no differences in the mean age of presentation and descending thoracic aorta diameter among those with variant or conventional arch anatomy. Patients with TBAD with variant arch anatomy had a higher percentage of dissection related thoracic aortic repairs (54.7% vs 33.6%; P = .004) with repairs occurring predominantly in the acute phase. 4D flow MRI demonstrated a higher systolic wall shear stress along the inner curve of the bovine arch compared with the conventional aberrant right subclavian artery arches. CONCLUSIONS: Variant aortic arch anatomy is significantly more prevalent in patients with TBAD. patients with TBAD with variant arch anatomy had a higher percentage of dissection-related aortic repair. Preliminary 4D flow MRI data show differences in hemodynamic flow patterns between variant and conventional arches. Studies of long-term outcomes based on arch anatomy may offer additional insight to TBAD genesis and possibly influence management decisions.
Authors: K Natsis; M Piagkou; N Lazaridis; T Kalamatianos; D Chytas; D Manatakis; N Anastasopoulos; M Loukas Journal: Surg Radiol Anat Date: 2021-01-02 Impact factor: 1.246