Arnoud V Kamman1, Jonathan L Eliason2, David M Williams3, Bo Yang4, Frans L Moll5, Santi Trimarchi6, Kim A Eagle7, Himanshu J Patel8. 1. Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands; Thoracic Aortic Research Center, Policlinico San Donato IRCCS, Milan, Italy; Department of Cardiac Surgery, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI. 2. Section of Vascular Surgery, University of Michigan, Ann Arbor, MI. 3. Department of Radiology, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI. 4. Department of Cardiac Surgery, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI. 5. Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands. 6. Thoracic Aortic Research Center, Policlinico San Donato IRCCS, Milan, Italy. 7. Department of Medicine, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI. 8. Department of Cardiac Surgery, Frankel Cardiovascular Center, University of Michigan, Ann Arbor, MI. Electronic address: hjpatel@med.umich.edu.
Abstract
BACKGROUND: The impact of left subclavian artery (LSA) revascularization before thoracic endovascular aortic repair (TEVAR) on cerebrovascular flow is not well described. We studied bilateral vertebral and carotid artery flow characteristics before and after TEVAR to evaluate the hemodynamic effects of LSA revascularization. METHODS: Seventy-four patients with mixed etiologies (mean age 70.9 ± 10.5 years) underwent LSA revascularization and TEVAR (2006-2016) and had available preoperative and postoperative carotid duplex study available. Data from patient demographics, procedures, preoperative, and postoperative carotid duplex studies were gathered. Revascularization was by left common carotid artery (LCCA) to LSA bypass (n = 70, 94.6%) or LSA to LCCA transposition (n = 4, 5.4%). RESULTS: Duplex confirmation of antegrade left vertebral artery (LVA) flow decreased significantly after TEVAR with LSA revascularization (100.0% vs. 77.9%, P < 0.001). Incidence of retrograde LVA flow increased from 0.0% to 8.3% (P = 0.063). Postoperatively, LVA bidirectional flow was observed in 3 patients (4.4%). Flow directions in the right vertebral artery (RVA) did not change significantly. Peak systolic velocity (PSV) in the LVA decreased significantly after TEVAR from 55.1 ± 22.0 cm/s to 35.9 ± 26.3 cm/s (P < 0.001). In contrast, PSV increased in the RVA and the right internal carotid artery (ICA; 52.2 ± 21.7 cm/s to 63.2 ± 23.3 cm/s, P = 0.012 and 95.3 ± 46.8 cm/s to 102.8 ± 42.9 cm/s, P = 0.011). PSV did not change significantly in the left ICA. At mean follow-up of 36.6 ± 26.8 months, primary bypass patency was 100.0%. Postoperatively, one case of temporary spinal cord ischemia was seen (1.4%). Stroke rate was 6.9% (n = 5, 100.0% embolic), all without permanent disabilities. Stroke circulation distribution was 60.0% posterior, 20.0% anterior, and 20.0% mixed. Location of stroke was left sided (n = 2) or in both hemispheres (n = 3). There were no deaths at 30 days. Neurological events during follow-up included 3 new strokes. All-cause mortality rate during follow-up was 12.2% (n = 9). CONCLUSIONS: Adjunctive LSA revascularization in the setting of zone 2 TEVAR coverage is associated with hemodynamic vertebral artery changes. Future studies in larger sample sizes should evaluate whether these novel findings are an important determinant of postoperative neurologic events.
BACKGROUND: The impact of left subclavian artery (LSA) revascularization before thoracic endovascular aortic repair (TEVAR) on cerebrovascular flow is not well described. We studied bilateral vertebral and carotid artery flow characteristics before and after TEVAR to evaluate the hemodynamic effects of LSA revascularization. METHODS: Seventy-four patients with mixed etiologies (mean age 70.9 ± 10.5 years) underwent LSA revascularization and TEVAR (2006-2016) and had available preoperative and postoperative carotid duplex study available. Data from patient demographics, procedures, preoperative, and postoperative carotid duplex studies were gathered. Revascularization was by left common carotid artery (LCCA) to LSA bypass (n = 70, 94.6%) or LSA to LCCA transposition (n = 4, 5.4%). RESULTS: Duplex confirmation of antegrade left vertebral artery (LVA) flow decreased significantly after TEVAR with LSA revascularization (100.0% vs. 77.9%, P < 0.001). Incidence of retrograde LVA flow increased from 0.0% to 8.3% (P = 0.063). Postoperatively, LVA bidirectional flow was observed in 3 patients (4.4%). Flow directions in the right vertebral artery (RVA) did not change significantly. Peak systolic velocity (PSV) in the LVA decreased significantly after TEVAR from 55.1 ± 22.0 cm/s to 35.9 ± 26.3 cm/s (P < 0.001). In contrast, PSV increased in the RVA and the right internal carotid artery (ICA; 52.2 ± 21.7 cm/s to 63.2 ± 23.3 cm/s, P = 0.012 and 95.3 ± 46.8 cm/s to 102.8 ± 42.9 cm/s, P = 0.011). PSV did not change significantly in the left ICA. At mean follow-up of 36.6 ± 26.8 months, primary bypass patency was 100.0%. Postoperatively, one case of temporary spinal cord ischemia was seen (1.4%). Stroke rate was 6.9% (n = 5, 100.0% embolic), all without permanent disabilities. Stroke circulation distribution was 60.0% posterior, 20.0% anterior, and 20.0% mixed. Location of stroke was left sided (n = 2) or in both hemispheres (n = 3). There were no deaths at 30 days. Neurological events during follow-up included 3 new strokes. All-cause mortality rate during follow-up was 12.2% (n = 9). CONCLUSIONS: Adjunctive LSA revascularization in the setting of zone 2 TEVAR coverage is associated with hemodynamic vertebral artery changes. Future studies in larger sample sizes should evaluate whether these novel findings are an important determinant of postoperative neurologic events.
Authors: Ali Hage; Olivia Ginty; Adam Power; Luc Dubois; Francois Dagenais; Jehangir J Appoo; John Bozinovski; Michael W A Chu Journal: Ann Cardiothorac Surg Date: 2018-05