Spinal cord ischemia and reinterventions following thoracic endovascular repair for acute type B aortic dissections.

OBJECTIVE: The technical aspects of thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection (TBAD), specifically the location of proximal seal zone (PSZ) (need to cover the left subclavian artery [LSA]), distal seal zone (DSZ) (length of aortic coverage), benefit of LSA revascularization, and prophylactic lumbar drainage are still debated. Each of these issues has potential benefits but also has known risks. This study aims to identify factors associated with reintervention and spinal cord ischemia (SCI) following TEVAR for acute TBAD with a zone 3 entry tear. METHODS: The Vascular Quality Initiative was queried for TEVARs performed for acute TBAD with zone 3 entry tear, zone 3 proximal zone of disease, treated with TEVAR extending between zone 2 and zone 5. The primary outcomes were SCI and related reintervention. Secondary outcomes were stroke, arm ischemia, and retrograde type A dissection (RTAD). The exposure variables were PSZ 2 vs 3, DSZ 4 vs 5, prophylactic lumbar drain, and LSA revascularization. Univariate analyses were conducted with χ2 analysis, and multivariable logistic regression was used to evaluate association with outcomes. RESULTS: Of 583 patients who met inclusion criteria, 266 had PSZ 2 and 317 had PSZ 3. On univariate analysis, PSZ 2 was associated with a higher rate of reintervention, but PSZ2 was not significant on multivariable analysis after accounting for age, sex, race, smoking, PSZ, DSZ, prophylactic lumbar drain, and LSA patency. PSZ 2 was not associated with SCI, arm ischemia, or RTAD. PSZ 2 was associated with a trend towards a higher rate of stroke. DSZ 4 and DSZ 5 were performed in 161 and 422 TEVARs, respectively, and DSZ 5 was associated with a higher rate of SCI on univariate (3 [1.9%] vs 39 [9.2%]; P = .01) and multivariable (odds ratio, 7.384; 95% confidence interval, 2.193-24.867; P = .001) analyses. Prophylactic lumbar drain placement was not statistically significantly associated with SCI, but lack of postoperative LSA patency was associated with SCI (odds ratio, 2.966; 95% confidence interval, 1.016-8.656; P = .05). CONCLUSIONS: This study found that PSZ 2 was not associated with lower reinterventions or higher rates of SCI but trended towards a higher rate of stroke than PSZ 3. Additionally, DSZ 5 was strongly associated with SCI when compared with DSZ 4, highlighting the importance of limiting aortic coverage to coverage of the proximal entry tear when possible.

Readmission after early thoracic endovascular aortic repair versus medical management of acute type B aortic dissection.

BACKGROUND: The use of thoracic endovascular aortic repair (TEVAR) for the management of acute uncomplicated type B aortic dissection (TBAD) has increased. Although the results from early studies were promising, larger randomized trials evaluating TEVAR are lacking. It is also unclear where sufficient equipoise exists for such trials. In the present study, we evaluated the number of readmissions and unplanned operations after TEVAR vs those after medical management as the initial treatment of acute uncomplicated TBAD and the frequency of each treatment in this population. METHODS: We performed a multi-institutional retrospective review of patients with acute TBAD from 2015 to 2020 with the 1-year outcomes available, excluding patients with prior aortic intervention or chronic, iatrogenic or traumatic etiologies. The primary exposure was TEVAR vs medical management at the index admission. The patient demographics, clinical presentation, and imaging findings were analyzed using bivariate and multivariate logistic regression for the primary outcomes of unplanned readmission and/or operation after the initial admission. The secondary outcomes were mortality, myocardial infarction, stroke, renal failure requiring dialysis, retrograde type A dissection, and length of stay. We hypothesized that the readmissions would be higher with medical management. RESULTS: A total of 216 patients with TBAD (47 with complicated and 169 with uncomplicated) from two large academic centers were identified. Of the 169 patients with uncomplicated TBAD, 83 (49%) had been treated medically and 86 (51%) had undergone TEVAR at the initial admission. No differences were found in the demographics or high-risk imaging features at presentation. The medically managed patients had had higher rates of unplanned readmission (34% vs 9%; P = .0001) and operation (28% vs 8%; P = .0007) but shorter lengths of stay (6.3 vs 13.1 days; P < .0001). No differences were found in mortality, although the rate of myocardial infarction was higher in the medically managed group (10.8% vs 2.3%; P = .02). Although 28% of the medically managed patients had later required operation, they had had morbidity and mortality similar to those of patients who had undergone initial TEVAR. Initial medical management was associated with unplanned readmission (odds ratio, 8.3; P = .02) and the need for operation (odds ratio, 4.56; P = .006). No differences were found in the outcomes according to the involved aortic zones. CONCLUSIONS: In the present study, medical management of acute uncomplicated TBAD was associated with higher rates of readmission and the need for unplanned operation compared with TEVAR. However, no differences were found in the 1-year mortality for the patients for whom medical management had failed. Because one half of the patients had undergone medical management and one half had undergone early TEVAR, this finding suggests clinical equipoise for the treatment of acute uncomplicated TBAD. Therefore, a larger randomized trial appears warranted to determine whether a clear benefit exists for early TEVAR.

False Lumen Intercostal Artery Embolization to Halt Type R Entry Flow in Chronic Type B Aortic Dissection.

BACKGROUND: Treatment of aneurysmal type B aortic dissection often involves thoracic endovascular aortic repair (TEVAR). However, persistent patency of the false lumen from type R entry flow is common and is associated with late complications including rupture. We describe 9 patients with aneurysmal chronic type B aortic dissections and patent false lumens and 7 despite prior thoracic endovascular aortic repair. The goal of the false lumen intercostal embolization in these patients was to achieve propagation of false lumen thrombosis (FLT) and to prevent spinal cord ischemia (SCI) using a staged approach in the overall treatment of their complex aortic aneurysm. METHODS: A multicenter retrospective review was performed of all consecutive false lumen intercostal embolization procedures; 9 were identified. Preoperative and postoperative computed tomographic angiograms were compared. We hypothesized that embolization was a safe and feasible treatment option. The primary outcome was procedural characteristics and SCI to establish safety and feasibility. Secondary outcomes included a change in supraceliac patent false lumen length and other perioperative clinical outcomes. RESULTS: In total, 30 of 31 (97%) targeted false lumen intercostal arteries were successfully coiled. Median procedural time was 57 min (interquartile range [IQR] 23-99), median air kerma was 585 mGy (IQR 398-1,644), and median contrast dose was 141 mL (IQR 74-240). After embolization, all patients demonstrated propagation of FLT, with mean false lumen length decreasing by 48% from 13.8 cm to 6.6 cm. There was no mortality associated with this procedure; 2 patients suffered a lumbar drain-related complication; 1 with cerebrospinal fluid leak and 1 with a spinal hematoma that was managed conservatively with no neurological deficit. No other complications occurred. CONCLUSIONS: In this review, false lumen intercostal coil embolization was technically feasible and did not result in any cases of SCI. The procedures required acceptable amounts of operative time, fluoroscopic dose, and contrast. All patients experienced propagation of FLT and no long-term procedure-related morbidity was noted. More data will be required to ascertain whether this procedure is effective at halting type R entry flow, preventing future type II entry flow, and promoting aortic remodeling over time.

Transposition of anomalous left vertebral to carotid artery during the management of thoracic aortic dissections and aneurysms.

OBJECTIVES: Preservation of antegrade flow to the left vertebral artery (LVA) is often achieved by transposition or bypass to the left subclavian artery during zone 2 thoracic endovascular aortic repair. An anomalous LVA (aLVA) originating directly from the aortic arch is a common arch variant with a reported incidence of 4% to 6%. In addition, 6% to 10% of vertebral arteries terminate in a posterior inferior cerebellar artery, increasing the risk of stroke if not revascularized. Few series of aLVA to carotid transposition have been reported. The aim of this study was to evaluate the outcomes of patients who underwent aLVA to carotid transposition for the management of aortic disease. METHODS: A retrospective review of all aLVA-carotid transpositions performed for the management of thoracic aortic dissection or aneurysm at a single center from 2018 to 2021 was performed. The primary outcomes were postoperative stroke and patency of the transposed aLVA. Secondary outcomes were spinal cord ischemia, postoperative cranial nerve injury, and Horner's syndrome. RESULTS: Seventeen patients underwent aLVA to carotid transposition as an adjunct to management of aortic disease during the study period. Most were men (n = 14) and the mean age was 54 ± 16 years. The primary indication for aortic repair was dissection in 10, aneurysm in 6, and Kommerell diverticulum in 1. Nine patients underwent zone 2 thoracic endovascular aortic repair, seven received open total arch repair, and there was one attempted total endovascular arch repair that was aborted owing to unfavorable anatomy. Twelve transpositions were performed before or concomitant with planned aortic repair owing to high-risk cerebrovascular anatomy (three posterior inferior cerebellar artery termination, six dominant aLVA, four intracranial LVA stenosis), and two were performed postoperatively for treatment of type II endoleak. LVA diameter ranged from 2 to 6 mm (mean, 3.3 mm). The mean operative time for transposition was 178 ± 38 minutes, inclusive of left subclavian artery revascularization, and the mean estimated blood loss was 169 ± 188 mL. No patients experienced 30-day postoperative spinal cord ischemia, stroke, or mortality. There were two cases of postoperative hoarseness, presumably owing to recurrent laryngeal nerve palsy, both of which resolved within 4 months. There were no cases of Horner's syndrome. At follow-up (mean, 306 days; range, 6-714 days), all transpositions were patent. CONCLUSIONS: Vertebral-carotid transposition is a safe and effective adjunct in the management of aortic disease with anomalous origin of the LVA.

Comparative early results of in situ fenestrated endovascular aortic repair and other emergent complex endovascular aortic repair techniques for ruptured suprarenal and thoracoabdominal aortic aneurysms at a regional aortic center.

INTRODUCTION: Emergent endovascular repair of suprarenal (SRAAAs) and thoracoabdominal aortic aneurysms (TAAAs) poses a significant challenge due to the need for branch vessel incorporation, time constraints, and lack of dedicated devices. Techniques to incorporate branch vessels have included parallel grafting, physician-modified endografts, double-barrel/reversed iliac branch device, and in situ fenestration (ISF). This study describes a single-center experience and the associated outcomes when using these techniques for ruptured SRAAAs and TAAAs. METHODS: A retrospective review of patients who underwent endovascular repair of ruptured SRAAAs and TAAAs from July 2014 to March 2021 with branch vessel incorporation was performed. Clinical presentation, intraoperative details, and postoperative outcomes of those who underwent ISF were compared with those who underwent repair using non-ISF techniques. The primary outcome of interest was in-hospital mortality. Secondary outcomes were major adverse events including myocardial infarction, respiratory failure, renal dysfunction, new onset dialysis, bowel ischemia, stroke, and spinal cord ischemia. RESULTS: Forty-two patients underwent endovascular repair for ruptured SRAAAs and TAAAs, 18 of whom underwent ISF repair. Seventy-two percent of ISF patients were hypotensive before surgery, compared with 46% of the patients who underwent repair using non-ISF techniques (physician-modified endografts, parallel grafting, or double-barrel/reversed iliac branch device). The total procedural and fluoroscopy times were similar between the two groups despite a greater mean number of branch vessels incorporated with the ISF technique (3.1 vs 2.2 per patient, P = .015). In-hospital mortality was 19% for all ruptures and 25% for ruptures with hypotension. Compared with the non-ISF group, in-hospital mortality trended lower in the ISF group (11% vs 25%, P = .233), reaching statistical significance when comparing patients who presented with hypotension (8% vs 45%, P = .048). The rate of major adverse events was 57% across all techniques and did not significantly differ between the ISF and non-ISF groups, with postoperative renal dysfunction being the most frequent complication (48%). Overall, ISF became the most commonly used technique later in the study period. CONCLUSIONS: Although emergent endovascular repair of ruptured SRAAAs/TAAAs remains a challenge, a number of techniques are available for expeditious treatment. In this series, ISF was associated improve survival, including a fivefold reduction in mortality in patients presenting with hypotension, and has now become the dominant technique at our center. Despite these advantages, postoperative complications and reinterventions are common. Further experience and longer-term follow-up are needed to validate these initial results and assess durability.

Impact of high-risk features and timing of repair for acute type B aortic dissections.

OBJECTIVE: The new Society for Vascular Surgery/Society for Thoracic Surgery reporting standards for type B aortic dissection (TBAD) categorize clinical presentations of aortic dissection into uncomplicated, high-risk features (HRF), and complicated groups. Although it is accepted that complicated dissections require immediate repair, the optimal timing of repair for HRF has yet to be established. This study aims to identify the ideal timing of thoracic endovascular aortic repair (TEVAR) for HRF, as well as outcomes associated with specific HRF. METHODS: The Vascular Quality Initiative was queried for TEVARs performed for acute and subacute TBAD with HRF from 2014 to 2020. Rupture, malperfusion, and uncomplicated patients were excluded. HRF were defined per the guidelines as refractory hypertension, pain, or rapid expansion/aneurysm of more than 40 mm. The primary outcomes were in-hospital/30-day mortality and 1-year survival with primary exposure variables being days from symptoms to repair and number of HRFs. Secondary outcomes were spinal cord ischemia, stroke, and retrograde type A dissection (RTAD). RESULTS: Of the 1100 patients who met inclusion criteria, 811 had one HRF, 249 had two, and 40 had three. There were no significant differences in primary or secondary outcomes based on number of HRFs. There were 309 patients who underwent repair at 0 to 2 days, 262 at 3 to 6 days, 270 at 7 to 14 days, and 259 at 15 days or more. TEVAR performed at 15 days or more was independently associated with lower in-hospital/30-day mortality (odds ratio, 0.38; P = .0388) and improved 1-year survival. Postoperative stroke was associated with earlier repair (0-2 days). There was no association of timing of repair with spinal cord ischemia, retrograde type A dissection or reintervention. CONCLUSIONS: TEVAR for TBAD with HRF delayed at least 15 days from symptom onset is associated with improved survival, supporting the theory that it is best to delay TEVAR until the subacute phase. Additionally, TEVAR delayed at least 3 days is associated with a decrease in stroke. Having more than one HRF was not associated statistically with worse outcomes. Because the classification of HRF is relatively new and without guidelines for repair, this study highlights the risks of early intervention for HRF and suggests that these patients seem to benefit from at least a short stabilization period before TEVAR.

Impact of Perioperative Blood Transfusion in Anemic Patients Undergoing Infra Inguinal Bypass.

OBJECTIVE: Patients who present with lower extremity ischemia are frequently anemic and the optimal transfusion threshold for this cohort remains controversial. We sought to evaluate the impact of blood transfusion on postoperative major adverse cardiac events (MACE), including myocardial infarction, dysrhythmia, stroke, congestive heart failure, and 30-day mortality for these patients. METHODS: All consecutive patients who underwent infra-inguinal bypass at our institution from 2011 to 2020 were included. Perioperative red blood cell transfusion was the primary exposure, and the primary outcome was MACE. Univariate and multivariable analyses were performed to assess the impact of patient and procedural variables, including red blood cell transfusion, stratified by hemoglobin (Hgb) nadir: <7, 7-8, and >8 g/dL. RESULTS: Of the 287 patients reviewed for analysis, 146 (50.9%) had a perioperative transfusion (mean: 1.6 ± 3 units). Patients who received a transfusion had a mean nadir Hgb of 8.3 ± 1.0 g/dL, compared to 10.1 ± 1.7 g/dL without a transfusion. The overall incidence of MACE was 15.7% (45 of 287 patients). Univariate analysis demonstrated that MACE was associated with blood transfusion (P = 0.009), lower Hgb nadir (P = 0.02), and higher blood loss (P = 0.003). On multivariate analysis, transfusion was independently associated with MACE for patients with a Hgb nadir >8 g/dL (OR: 3.09; P = 0.006), but not for patients with Hgb nadir 7-8 g/dL (OR: 0.818; P = 0.77). Additionally, patients with MACE had significantly longer length of hospital stay than for patients without (13 vs. 7.7 days, P = 0.001). CONCLUSIONS: For patients undergoing infra-inguinal bypass, receiving a red blood cell transfusion with a Hgb nadir >8 g/dL was associated with a 3-fold increase in MACE, with nearly twice the length of stay. For patients with a Hgb 7-8 g/dL, transfusion did not increase or reduce the incidence of MACE. These findings suggest no benefit of blood transfusion for patients with Hgb nadir >7 g/dL and harm for Hgb >8 g/dL, however causation cannot be proven due to the retrospective nature of the study and randomized studies are needed to confirm or refute these findings.

Endovascular versus open repair of isolated superficial femoral and popliteal artery injuries.

OBJECTIVE: Despite the increasing use of endovascular therapy for traumatic arterial injuries, little is known about the outcomes of endovascular repair of superficial femoral artery (SFA) and popliteal artery (PA) injuries. In the present study, we compared the characteristics and outcomes of endovascular vs open repair of traumatic SFA and PA injuries. METHODS: We performed a retrospective National Trauma Data Bank analysis of trauma patients with a blunt or penetrating injury of the SFA and/or PA who had undergone endovascular or open repair from 2007 to 2014. Multivariate logistic regression was used to compare the outcomes, with propensity score matching used for sensitivity analysis. RESULTS: The incidence of SFA and PA injuries was 0.2%, with an overall increase in the annual use of endovascular stent repair from 3.2% in 2007 to 7.6% in 2014 (P = .002). A total of 2,873 patients with an isolated SFA and/or PA injury were included in the present study, of whom 163 (5.7%) had undergone endovascular repair. SFA injuries were more frequently treated with endovascular repair (70% vs 27%) and PA injuries were more often associated with open repair (41.1% vs 54.7%). Open repair was more frequently associated with a concomitant femur fracture or knee dislocation (30.7% vs 38.8%; P = .039). Endovascular repair was not associated with worse in-hospital amputation-free survival (AFS) compared with open repair on univariate analysis (91.1% vs 89.7%; P = .573) or multivariate logistic regression (odds ratio [OR], 1.053; 95% confidence interval [CI], 0.551-2.012; P = .876). Propensity score matching revealed that in-hospital mortality was higher (OR, 3.69; 95% CI, 1.37-9.82; P = .01) and fasciotomy was lower (OR, 0.23; 95% CI, 0.14-0.37; P < .001) in the endovascular repair group, with no significant differences in AFS (OR, 0.86; 95% CI, 0.48-1.67; P = .65). CONCLUSIONS: Endovascular repair of SFA and PA injuries has in-hospital AFS comparable to that for open repair, supporting the increasing use of endovascular repair for traumatic SFA and PA injuries in appropriately selected cases. Given the unexpected finding of increased in-hospital mortality after endovascular repair, further studies are necessary to determine the appropriate patient selection and the durability of endovascular repair.

Technique for transcarotid artery revascularization of tandem lesions.

The repair of tandem carotid lesions has been described using myriad methods, often involving a hybrid approach of stenting with carotid endarterectomy. Because of the worrisome stroke rates associated with this method, we have reported an innovative technique of transcarotid artery revascularization (TCAR) for tandem lesions in a patient with high-grade stenosis of the right common and internal carotid arteries. Technical success was achieved with TCAR via retrograde and antegrade access using dynamic flow reversal for the treatment of both lesions. The patient experienced no postoperative complications, highlighting the successful repair of tandem carotid lesions using TCAR in a patient who is too high risk for carotid endarterectomy.