Faculty Bibliography

OBJECTIVE:Beta-blockers are first-line anti-impulse therapy in patients presenting with acute type B aortic dissection (TBAD). However, little is understood about their impact after aortic repair. The aim of this study was to evaluate the role of postoperative beta-blocker use on outcomes of thoracic endovascular aortic repair (TEVAR) in TBAD. METHODS:The Vascular Quality Initiative database was queried for all patients undergoing TEVAR for TBAD from 2012 to 2020. Aortic-related reintervention, all-cause mortality and effect of TEVAR on false lumen thrombosis of the treated aortic segment were assessed and compared between patients treated with and without beta-blocker postoperatively. Cox proportional hazards models were used to estimate the effect of beta-blocker therapies on outcomes. RESULTS:1,114 patients undergoing TEVAR for TBAD were identified with a mean follow-up of 18±12 months. The mean age was 61.1±11.9 years, and 791 (71%) were male. 935 (84%) patients were maintained on beta-blocker at discharge and follow-up. Patients on beta-blocker were more likely to have an entry tear originating in zones 1-2 (22% vs 13%; P=.022). The prevalence of acute, elective and symptomatic AD, concurrent aneurysm, number of endografts used, distribution of the proximal and distal zones of dissection and operative time were comparable between the two cohorts. At 18-months, significantly more complete false lumen thrombosis (58 vs 47%; log-rank P=.018) was observed in patients on beta-blocker while the rates of aortic-related reinterventions (13% vs 9%; log-rank P=.396) and mortality (0.2% vs 0.7%; log-rank P=.401) were similar in patients with and without beta-blocker, respectively. Even after adjusting for clinical and anatomic factors, postoperative beta-blocker use was associated with increased complete false lumen thrombosis (HR 1.56; 95% CI: 1.10-2.21; P=.012) but did not affect mortality or aortic-related reintervention. A secondary analysis of beta-blocker use in acute versus chronic TBAD showed a higher rate of complete false lumen thrombosis in patients on beta-blocker in chronic TBAD (59% vs 38%; log-rank P=.038). In contrast, there was no difference in the rate of complete false lumen thrombosis in acute TBAD between the two cohorts (58% vs 51%; log-rank P=.158). When analyzed separately, postoperative ACE inhibitor use did not affect the rates of complete false lumen thrombosis, mortality and aortic-related reintervention. CONCLUSIONS:Beta-blocker use was associated with promotion of complete false lumen in patients undergoing TEVAR for TBAD. In addition to its role in acute setting, anti-impulse control with beta-blocker appears to confer favorable aortic remodeling and may improve outcomes after TEVAR, particularly for chronic TBAD.

OBJECTIVE:The optimal medical management strategy in the periprocedural period for patients undergoing carotid artery interventions is not well described. Renin-angiotensin-system blocking (RASB) agents are considered to be among the first line anti-hypertensive agents; however, their role in the perioperative period is unclear. The objective of this study was to examine the relationship between the use of RASB agents on periprocedural outcomes in patients undergoing carotid interventions-carotid endarterectomy (CEA), transfemoral carotid artery stenting (CAS), and transcervical carotid artery revascularization (TCAR). METHOD/METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing CAS, CEA, and TCAR between 2003 and 2020. Patients were stratified into two groups based upon their use of RASB agents in the periprocedural period. The primary endpoint was periprocedural neurologic events (including both strokes and transient ischemic attacks (TIAs)). The secondary endpoints were peri-procedural mortality and significant cardiac events, including myocardial infarction, dysrhythmia, and congestive heart failure. RESULTS:= 0.461). CONCLUSION/CONCLUSIONS:The use of peri-procedural RASB agents was associated with a significantly decreased rate of neurologic events in patients undergoing both CEA and TCAR. This effect was not observed in patients undergoing CAS. As carotid interventions warrant absolute minimization of perioperative complications in order to provide maximum efficacy with regard to stroke protection, the potential neuro-protective effect associated with RASB agents use following CEA and TCAR warrants further examination.

OBJECTIVE:Data on the efficacy of non-reversed and reversed great saphenous vein bypass (NRGSV and RGSV) techniques are lacking. The aim of the study was to compare the outcomes of patients undergoing open infrainguinal revascularisation using NRGSV and RGSV from a multi-institutional database. METHODS:The Vascular Quality Initiative database was queried for patients undergoing infrainguinal bypasses using NRGSV and RGSV for symptomatic occlusive disease from January 2003 to February 2021. The primary outcome measures included primary and secondary patency at discharge and one year. Secondary outcomes were re-interventions at discharge and one year. Cox proportional hazards models were used to evaluate the impact of graft configuration on outcomes of interest. RESULTS:Of 7 123 patients, 4 662 and 2 461 patients underwent RGSV and NRGSV, respectively. At one year, the rates of primary patency (78% vs. 78%; p = .83), secondary patency (90% vs. 89%; p = .26), and re-intervention (16% vs. 16%; p = .95) were similar between the RGSV and NRGSV cohorts, respectively. Subgroup analysis based on outflow bypass target and indication for revascularisation did not show differences in primary and secondary outcomes between the two groups. Multivariable analysis confirmed that RGSV (NRGSV as the reference) configuration was not independently associated with increased risk of primary patency loss (hazard ratio [HR] 1.01; 95% confidence interval [CI] 0.91 - 1.13; p = .80), secondary patency loss (HR 0.94; 95% CI 0.81 - 1.10; p = .44), and re-intervention (HR 1.03; 95% CI 0.91 - 1.16; p = .67) at follow up. CONCLUSION/CONCLUSIONS:The study shows that RGSV and NRGSV grafting techniques have comparable peri-operative and one year primary and secondary patency and re-intervention rates. This effect persisted when stratified by outflow targets and indication for revascularisation. Therefore, optimal selection of vein grafting technique should be guided by the patient's anatomy, vein conduit availability, and surgeon's experience.

BACKGROUND:Potential complications of pelvic flow disruption during aortic aneurysm repair include buttock ischemia and mesenteric ischemia. Unilateral or bilateral hypogastric artery flow interruption, either from atherosclerosis or intentionally to facilitate aneurysm repair, is considered problematic in endovascular repair; however, it has not been well studied in open abdominal aortic aneurysm (AAA) repair (OAR). We sought to examine the effect of interruption of flow to one or both hypogastric arteries on outcomes after OAR. METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. (redundant) Patients with appropriate data on their hypogastric arteries postoperatively were stratified into two groups-patent bilaterally (normal pelvic perfusion, NPP) and unilateral or bilateral occlusion or ligation (compromised pelvic perfusion, CPP). Primary endpoints were 30-day major morbidity (myocardial infarction, respiratory complications, renal injury, and lower extremity or intestinal ischemia) and mortality. RESULTS:During the study period, 9.492 patients underwent elective open AAA repair-860 (9.1%) with compromised pelvic perfusion and 8,632 (90.9%) with patent bilateral hypogastric arteries. The groups had similar cardiac risk factors, including a history of coronary artery disease, prior coronary intervention, and the use of P2Y12 inhibitors and statins. A majority of patients in the CPP cohort had concurrent iliac aneurysms (63.3% vs. 24.8%; P < 0.001). The perioperative mortality was significantly higher in patients with compromised pelvic perfusion (5.5% vs. 3.1%; P < 0.001). Bilateral flow interruption had a trend toward higher perioperative mortality compared to unilateral interruption (7.1% vs. 4.7%; P < 0.147). The CPP group also had increased rates of myocardial injury (6.7% vs. 4.7%; P = 0.012), renal complications (18.9% vs. 15.9%; P = 0.024), leg and bowel ischemia (3.5% vs. 2.1%; P = 0.008; and 5.7% vs. 3.4%; P < 0.001, respectively). On multivariable analysis, CPP was associated with increased perioperative mortality (OR 1.47, CI 1.14-1.88, P = 0.003). On Kaplan-Meier analysis, there was no difference in survival at 2 years postdischarge between the NPP and CPP cohorts (86.1% vs. 87.5%, log-rank P = 0.275). CONCLUSIONS:Compromised pelvic perfusion is associated with increased perioperative complications and higher mortality in patients undergoing OAR. The sequelae of losing pelvic perfusion, in addition to the presence of more complex atherosclerotic and aneurysmal disease resulting in more difficult dissection, likely contribute to these findings. Thus, patients considered for OAR who have occluded hypogastric arteries or aneurysmal involvement of the hypogastric artery preoperatively may be candidates for more conservative management beyond traditional size criteria.

BACKGROUND:Mannitol is often administered during open juxtarenal or suprarenal aortic surgery to prevent ischemic injury to the kidneys. Prior evidence evaluating the benefits of intraoperative mannitol in reducing ischemia/reperfusion injury is conflicting and largely based on small, retrospective series. The aim of this study was to evaluate the effect of mannitol in preventing postoperative hemodialysis in patients undergoing open abdominal aortic aneurysm (AAA) repair where proximal control involved temporary renal ischemia. METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. Patients were included in the current analysis if the proximal aortic clamp was placed above at least one renal artery. Chronic kidney disease (CKD) was defined as Cr > 1.8 mg/dL. Primary end points were 30-day major morbidity (myocardial infarction, respiratory complications, lower extremity or intestinal ischemia, and the need for temporary or permanent hemodialysis) and mortality. Comparisons were made between the mannitol and nonmannitol cohorts and stratified by the presence of preexisting CKD. RESULTS:During the study period, 4,156 patients underwent elective open AAA repair requiring clamp placement more than one (32.7%) or both (67.3%) renal arteries; 182 patients (4.4%) had preexisting CKD. Overall, 69.8% of patients received mannitol during their surgery. Mannitol was more frequently used in cases involving clamp placement above both renal arteries (70.3%) than one renal artery (61.5%). While prolonged ischemia time (more than 40 min) was associated with a higher risk of postoperative dialysis in patients without CKD, it was not significant in patients with baseline CKD. On a univariate analysis, mannitol use in patients with CKD was associated with a lower risk of postoperative dialysis (P = 0.005). This remained significant on a multivariate analysis (P = 0.008). Mannitol use did not appear to confer renal protective effects in patients without baseline CKD. CONCLUSIONS:Mannitol use was associated with a decreased risk of need for postoperative hemodialysis in patients with CKD undergoing suprarenal aortic clamping for open aneurysm repair. In appropriately selected patients, particularly those with underlying renal insufficiency, mannitol may confer a renal protective effect in open repair of pararenal AAA requiring suprarenal clamping.

OBJECTIVE:Autologous great saphenous vein (GSV) is considered the conduit of choice for lower extremity bypass (LEB). However, the optimal configuration remains the source of debate. We compared outcomes of patients undergoing LEB using in-situ and reversed techniques. METHODS:The Vascular Quality Initiative database was queried for patients undergoing LEB with a single-segment GSV in in-situ (ISGSV) and reversed (RGSV) configurations for symptomatic occlusive disease from 2003 to 2021. Patient demographics, procedural detail, and in-hospital and follow-up outcomes were collected. The primary outcome measures included primary patency at discharge or 30 days and one year. Secondary outcomes were secondary patency, and reinterventions at discharge or 30 days and one year. Cox proportional hazards models were created to determine the association between bypass techniques and outcomes of interest. RESULTS:= 0.985) at follow-up, compared to reversed bypass. A subgroup analysis of bypasses to crural targets showed that in-situ and reversed bypasses had similar rates of primary patency loss and reinterventions at 1 year. Among patients with chronic limb-threatening ischemia, in-situ bypass was associated with a decreased risk of reinterventions but similar rates of primary and secondary patency and major amputations at 1 year. CONCLUSIONS:In patients undergoing LEBs using the GSV, in-situ configuration was associated with more perioperative reinterventions and lower primary patency rate. However, this was offset by decreased risks of loss of primary patency and reinterventions at 1 year. A thorough intraoperative graft assessment with adjunctive imaging may be performed to detect abnormalities in patients undergoing in-situ bypasses to prevent early failures. Furthermore, closer surveillance of reversed bypass grafts is warranted given the higher rates of reinterventions.

Myocardial injury after non-cardiac surgery (MINS) is common. We investigated the incidence and outcomes of MINS, and mechanistic underpinnings using pre-operative whole blood gene expression profiling in a prospective cohort study of individuals undergoing lower extremity revascularization (LER) for peripheral artery disease (PAD). Major adverse cardiovascular and limb events (MACLE) were defined as a composite of death, myocardial infarction, stroke, major lower extremity amputation or reoperation. Among 226 participants undergoing LER, MINS occurred in 53 (23.5%). Patients with MINS had a greater incidence of major adverse cardiovascular events (49.1% vs. 22.0%, adjusted HR 1.87, 95% CI 1.07-3.26) and MACLE (67.9% vs. 44.5%; adjusted HR 1.66, 95% CI 1.08-2.55) at median 20-month follow-up. Pre-operative whole blood transcriptome profiling of a nested matched MINS case-control cohort (n = 41) identified upregulation of pathways related to platelet alpha granules and coagulation in patients who subsequently developed MINS. Thrombospondin 1 (THBS1) mRNA expression was 60% higher at baseline in patients who later developed MINS, and was independently associated with long-term cardiovascular events in the Duke Catheterization Genetics biorepository cohort. In conclusion, pre-operative THBS1 mRNA expression is higher in patients who subsequently develop MINS and is associated with incident cardiovascular events. Pathways related to platelet activity and coagulation associated with MINS provide novel insights into mechanisms of myocardial injury.

OBJECTIVE:Transplant renal artery stenosis (TRAS) after renal transplantation is a common cause of graft dysfunction and failure. Endovascular intervention in the form of percutaneous transluminal angioplasty (PTA) and stenting has rapidly become the dominant treatment modality for the TRAS. There is a paucity of clinical data on use of drug-eluting stent (DES) for TRAS. We investigated the outcomes of patients with clinically significant TRAS undergoing DES placement. METHODS:A retrospective review of patients with clinically significant TRAS undergoing PTA with DES placement from June 2014 to April 2021 was conducted. Patients treated for TRAS exhibited uncontrolled hypertension and/or unexplained allograft dysfunction. Patient demographics, procedural details, and follow-up outcomes were collected. Primary endpoints were the in-stent primary patency and graft survival. Secondary endpoints were freedom from reintervention, primary-assisted patency and access-related complications. RESULTS:Thirteen TRAS in twelve patients with graft function alteration were treated with DES. The median age was 57 years (interquartile range (IQR), 48-63 years), and nine (70%) patients were male (Table). The median follow-up was 9 months (IQR, 4-52 months). The most common comorbidity was hypertension (100%), coronary artery disease (83%) and diabetes. The median time from deceased donor transplant to intervention was 5.8 months (IQR, 3.5-6.7 months). TRAS was most commonly found at the juxta-ostial segment (77%). The procedure was performed with carbon dioxide angiography with minimal amount of iodinated contrast (median, 3 mL) under local anesthesia in nine (69%) and general anesthesia in four (31%) patients. The median stent diameter was 4.5 mm (IQR, 4-5 mm), and the median stent length was 15 mm (IQR, 15-18 mm). No intraoperative complications occurred. The rates of stenosis-free primary patency of the DES and graft survival were 76% and 100%, respectively. All three reinterventions for restenosis resulted from the kinking of the transplant renal artery proximal to the DES, which were treated by extending the stent more proximally 1-2 mm into the external iliac artery. There were no access-related complications. The median time to reintervention was 0.9 months (range, 0.23-2 months). Freedom from reintervention and primary-assisted patency were 76% and 100%, respectively. CONCLUSIONS:Our study demonstrates that DES is a safe and effective treatment modality in patients with TRAS at short to mid-term follow-up. As all reinterventions after DES were performed due to kinking of the transplant renal artery proximal to the stent, bridging of the DES 1-2 mm into the external iliac artery is recommended.