Outcomes of chimney/snorkel endovascular repair for symptomatic and ruptured abdominal aortic aneurysms.

OBJECTIVE: Symptomatic and ruptured abdominal aortic aneurysms (AAAs) are increasingly being managed with endovascular aneurysm repair (EVAR). We aimed to identify the outcomes of symptomatic and ruptured AAAs that had undergone EVAR with a chimney or snorkel technique (ChEVAR). METHODS: A retrospective cohort study was performed using the Vascular Quality Initiative registry from March 2013 to July 2019. All patients with symptomatic and ruptured AAAs with a proximal aortic zone of disease from 6 to 9 who had undergone ChEVAR were included. The outcomes were analyzed in accordance with the Society for Vascular Surgery reporting standards for EVAR. RESULTS: ChEVAR was performed in 77 patients (ruptured, 35 [45.5%]; symptomatic, 42 [54.5%]). The median age was 73.0 years (interquartile range [IQR], 67.0-81.0 years), and 54 patients (70.1%) were men. The median maximum aneurysm diameter was 67.5 mm (IQR, 54.5-83.3 mm). All patients had American Society of Anesthesiologists class ≥III. For the patients with ruptured AAAs, the mean lowest preoperative systolic blood pressure was 95.3 ± 29.3 mm Hg. The fluoroscopy time was 57.4 minutes (IQR, 41.2-79.0 minutes). The proximal aortic zone of disease was zone 6 in 9 (11.7%), zone 7 in 21 (27.3%), zone 8 in 36 (46.8%), and zone 9 in 11 (14.3%) patients. ChEVAR involved more than one vessel in 55 patients (71.4%). No significant difference was found in 30-day mortality between the patients with ruptured vs symptomatic AAAs (11.4% vs 7.1%; P = .695). Reintervention was required for 10 patients (13.0%) at a median of 9 postoperative days, 2 (20.0%) of whom died. Postoperatively, 31 patients (40.3%) had experienced a major complication. A type I endoleak had occurred in nine patients (11.7%), two (22.2%) of whom died. Long-term follow-up data were available for 38 patients (49.4%) at a median of 406.5 days (IQR, 326.8-602.0 days) postoperatively. Of the 18 patients with long-term radiographic data, sac growth was detected in 4 (22.2%). A total of 14 patients had died at a median of 26.5 days (IQR, 3.0-468.5 days). CONCLUSIONS: ChEVAR for symptomatic and ruptured AAAs can be performed with acceptable rates of morbidity and mortality. Long-term data are needed to determine the durability.

Periprocedural Outcomes of Popliteal vs Upper Extremity Access in the Treatment of Superficial Femoral Artery Occlusive Disease.

PURPOSE: Percutaneous lower extremity revascularization is being performed via upper extremity, pedal, or popliteal access with increasing frequency. This study aimed to compare periprocedural outcomes of popliteal (POA) and upper extremity (UEA) access for the treatment of isolated superficial femoral artery (SFA) occlusive disease. MATERIALS AND METHODS: A retrospective cohort study compared the outcomes of patients undergoing primary percutaneous intervention of SFA occlusive disease with POA or UEA using the Vascular Quality Initiative database from December 2010 to June 2019. Our primary endpoint was technical success. Secondary endpoints included factors associated with perioperative complications. RESULTS: A total of 349 patients underwent isolated SFA intervention through the popliteal, radial, or brachial artery. UEA was performed in 188 (53.9%) patients and POA in 161 (46.1%). Technical success with TASC A lesions was 95.8% and with TASC D lesions, 65.0%. POA had a higher proportion of TASC D lesions (24.8% vs 10.6%, p<0.001), and larger (≥7 Fr) sheath size (14.3% vs 2.7%, p<0.001). UEA had a higher proportion of no calcification (27.1% vs 11.2%, p<0.001), and smaller (4-5 Fr) sheath size (46.8% vs 34.8%, p=0.023). There was no difference in technical success between UEA and POA (88.8% vs 84.5%, p=0.230), which was also seen on multivariable analysis (p=0.985). Univariate analysis revealed technical failure was associated with TASC D lesions (45.7% vs 12.9%, p<0.001) and the presence of severe calcifications (39.1% vs 17.5%, p=0.002). Multivariable analysis confirmed technical failure was associated with degree of calcification (OR, 2.4; 95% CI, 1.18 to 4.89; p=0.016) and TASC D lesions (OR, 5.01; 95% CI, 2.45 to 10.24; p<0.001). Postoperative complications were associated with UEA on univariate (p=0.041) and multivariate analysis (OR, 2.08; 95% CI, 0.80 to 5.37; p=0.016). Access site complications were also associated with UEA compared to POA (4.3% vs 0.0%, p=0.027). CONCLUSIONS: There is no difference in technical success between UEA and POA when treating isolated SFA occlusive disease, and UEA is associated with a higher complication rate. Technical success is dependent on calcification and TASC II classification. Based on similar technical success rates and low complication rates, POA should be considered as a viable alternative to UEA when planning endovascular interventions.

Preoperative Stress Test and Postoperative MI in Patients Requiring Lower Extremity Bypass for Critical Limb Ischemia.

BACKGROUND: Patients with critical limb ischemia (CLI) often require lower extremity bypass surgery for limb salvage. A myocardial infarction (MI) is a major postoperative risk. Our objective is to assess the utility of preoperative stress test in determining patient outcomes. METHODS: This is a retrospective study utilizing the national Vascular Quality Initiative database. We collected data from 2013-2018 on all patients undergoing lower extremity bypass for CLI and assessed whether or not they had a preoperative stress test. Rates of an MI were then compared between groups of patients who either did not receive a stress test, had a normal stress test or a positive stress test. An MI was distinguished as troponin only and electrocardiogram (EKG)/clinical. Our secondary end point was in-hospital mortality. Univariate and multivariate analysis with the stress test as a covariate was used to determine significance. RESULTS: During this time period, 29,937 bypasses were performed on 27,219 patients. The average age was 67.5 years (±11.09), 66.3% were men, and 17.3% were African American. Risk factors included hypertension (89.5%), diabetes (55.9%), congestive heart failure (20%), coronary artery disease (32.5%), coronary artery bypass graft (22.2%), and percutaneous coronary intervention (21%). 19,108 patients (64.1%) did not undergo the stress test before bypass, 6,830 (22.9%) had a normal stress test, and 2,898 (9.7%) had a positive stress test. Overall rate of an MI was 4%, with 2% being troponin only and 2% EKG/clinical. The positive stress test had a higher rate of troponin only (2.85%) as well as EKG/clinical (3.37%) MI. For every 10 year increase in age, the odds of having a postoperative MI increased by 27% (P < 0.0001). Overall in-hospital mortality was 1.4%. Patients with positive stress tests had a 2.6% mortality compared with normal/not performed at 1.3%. Of the patients who died, 21.5% had an EKG/clinical MI. Of those patients, 50% did not have a stress test, 12% had normal stress tests, and 23% had positive stress tests. When comparing rates of patients who died or had an MI, there was no difference between patients who had no or a normal stress test (7.29%) versus those who had a positive stress test (7.58%), (P = 0.11). CONCLUSIONS: A positive stress test before lower extremity bypass is a significant predictor of a postoperative MI. However, mortality increase was minimal in patients with a positive stress test. Therefore, the stress test result should not delay care for patients needing urgent revascularization.

Cross-clamp location affects short-term survival in patients undergoing open abdominal aortic aneurysm repair.

INTRODUCTION: Open abdominal aortic aneurysm (oAAA) repair in the era of advanced endovascular aortic techniques is used in challenging anatomy. The impact of the location of the proximal aortic cross-clamp (suprarenal [SR] vs infrarenal [IR]) on outcomes remains to be determined. The aim of this study was to analyze the effect of proximal aortic cross-clamp location on short-term and overall survival after oAAA repair in a contemporary series. METHODS: A retrospective cohort study was performed comparing the outcomes of patients undergoing oAAA repair with SR and IR aortic cross-clamping using the Vascular Quality Initiative registry from January 2003 to September 2018. Our primary end point was short-term mortality. RESULTS: There were 7601 patients who underwent oAAA repair. Their mean age was 69.3 ± 8.5 years and 5555 patients (73.1%) were male. The aortic cross-clamp location was IR in 4044 patients (53.2%). The SR group had increased maximum AAA diameter (58 mm vs 56 mm; P < .0001), hypertension (85.5% vs 82.0%; P < .0001), preoperative creatinine (1.11 vs 1.08; P = .001), and were more likely to be in American Society of Anesthesiologists class IV (37.4% vs 30.6%; P < .0001). Postoperative renal failure occurred significantly more often in the SR group (24.4 vs 11.4%; P < .0001). Short-term mortality was 2.7% in the IR group and 4.7% in the SR group (P < .0001). Kaplan-Meier survival estimates were 93.7% and 83.8% in the IR group and 90.9% and 81.2% in the SR group at 1 and 5 years, respectively (P = .007). Multivariable analysis demonstrated that SR cross-clamping was significantly associated with short-term mortality (hazard ratio, 1.38; 95% confidence interval, 1.07-1.78; P = .01); however, it did not affect overall survival (hazard ratio, 1.13; 95% confidence interval, 1.00-1.28; P = .06). CONCLUSIONS: A SR cross-clamp location is associated with an increased short-term mortality in patients undergoing oAAA repair. Overall survival is not affected by a SR cross-clamp location.

Complexity of Aortic Arch Anatomy Affects the Outcomes of Transcarotid Artery Revascularization Versus Transfemoral Carotid Artery Stenting.

BACKGROUND: Transcarotid artery revascularization (TCAR) has been shown to have half the rates of transient ischemic attack (TIA), stroke, and death compared with transfemoral carotid artery stenting (TFCAS). Successful outcomes of TFCAS require careful patient selection. The aim of this study was to determine the outcomes of TFCAS versus TCAR in both simple (type I) and complex (type II and III) aortic arches. METHODS: A retrospective cohort study was performed comparing the outcomes of patients undergoing TFCAS versus TCAR with simple and complex aortic arches using the Vascular Quality Initiative registry from August 2011 to May 2019. The primary outcome was a composite of in-hospital TIA/stroke/death. RESULTS: About 6,108 carotid artery interventions were analyzed, including 3,536 (57.9%) patients with type I, 2,013 (33.0%) with type II, and 559 (9.2%) with type III aortic arch. In 3,535 patients with a simple arch, 1,917 underwent TFCAS and 1,619 had TCAR. Mean age was 70.6 (±9.5) years, and 2,382 (67.4%) patients were males. The primary outcome of postoperative TIA/stroke/death was seen significantly less frequently in those undergoing TCAR compared with TFCAS in simple arches (odds ratio [OR], 0.63; 95% confidence interval [95% CI], 0.43-0.94; P = 0.0236). Although the individual outcome of death occurred less often in TCAR (P = 0.0025), there was no difference in the occurrence of in-hospital stroke (P = 0.8836) or TIA (P = 0.4608). On multivariable analysis, TCAR was associated with improved outcomes (P = 0.0062). A worse outcome was associated with increasing age (P < 0.001), a prior stroke (P < 0.0001), and increasing number of stents (P = 0.0483). In 2,572 patients with a complex arch, 1,416 underwent TFCAS and 1,156 had TCAR. Mean age was 73.0 (±9.1) years, and 1,655 (64.4%) were males. In complex arch anatomy, the primary outcome of in-hospital TIA/stroke/death was seen significantly less frequently in TCAR compared with TFCAS (OR, 0.49; 95% CI, 0.31-0.77; P = 0.0022). Again noted was a significant difference in death, with better outcomes in TCAR (P = 0.0133). Although the occurrence of in-hospital TIA was no different between the 2 approaches (P = 0.6158), there were significantly fewer strokes in those treated with TCAR (P = 0.0132). TCAR (P = 0.0146) was associated with improved outcomes. A worse outcome was seen with advancing age (P = 0.0003), prior strokes (P = 0.01), and a left-sided lesion (P = 0.0176). CONCLUSIONS: TCAR has improved outcomes of TIA/stroke/death compared with TFCAS in both simple and complex aortic arch anatomy. In simple aortic arches, there is no difference in neurologic outcomes between both approaches. In complex arch anatomy, TCAR has fewer strokes.

Embolization Techniques for Arteriovenous Malformations in Parkes-Weber Syndrome.

BACKGROUND: Multiple high-flow arteriovenous malformations (AVMs) are the hallmark of Parkes-Weber syndrome (PWS). Surgical resection has historically shown poor outcomes with PWS. The aim of this study was to assess the management of PWS in the current era. METHODS: A retrospective review was performed from 2004 to 2017 on all patients presenting to a single institution for the management of PWS. Presentation, techniques, complications, and outcomes were reviewed. RESULTS: Fourteen patients (50% male) with PWS were seen at our institution, and mean age was 19.9 years (range, 4.7-68.8). The lower extremity was affected in 12 (86%) and the upper extremity in 2 (14%) patients. All patients presented with pain and swelling in the affected limb. Seven (50%) patients presented with ulcers, of which 3 (43%) had extensive wounds. Five (36%) patients had echocardiographic evidence of high-output cardiac failure. All patients underwent angiography with the intention to treat. Three (21%) patients were found to have diffuse arteriovenous communication with no discrete AVM nidus and thus did not undergo intervention. The remaining 11 (79%) patients underwent transcatheter embolization of the AVM's arterial inflow. Six (55%) patients required multiple or staged inflow embolization procedures, with a mean of 3.3 (range, 1-10) interventions. Thirty-two arterial embolization procedures were performed in total. n-Butyl-2-cyanoacrylate (nBCA) adhesive was used in 22 (69%), microspheres in 8 (25%), and a combination of coils and nBCA adhesive in 2 (6%) cases. Technical angiographic success was seen in all patients. Six (55%) patients also had interventions to treat the venous component of the malformation, either concomitantly or during a separate procedure. This included radiofrequency ablation in 1 (17%), coil embolization in 1 (17%), sodium tetradecyl sulfate (STS) sclerotherapy in 2 (33%), and a combination of STS, coil embolization, and vein stripping in 2 (33%) patients. Ten (91%) patients experienced a partial response and 1 (9%) patient experienced no response to treatment. No patients had a complete response, as expected with the diffuse nature of this disease. There were no periprocedural complications. Two of 3 patients with complex wounds required major amputations for gangrene, including one above-knee and one below-knee amputation at 128 months and 66 months after the index procedure, respectively. CONCLUSIONS: AVMs in PWS can be successfully treated by a transcatheter approach. Multiple interventions are usually required. Patients with extensive wounds remain at risk for loss of limb.

Major Limb Amputations in Patients with Congenital Vascular Malformations.

BACKGROUND: The need for major amputations in patients with vascular malformations is rare. This study reviews our contemporary experience with major amputations in patients with vascular malformations. METHODS: A retrospective review from April 2014 to November 2018 identified 993 patients undergoing management of a vascular malformation involving the upper or lower extremity at a tertiary center. This population was analyzed to identify those requiring either a transfemoral or transhumeral amputation. This cohort was investigated for clinical course, surgical procedures, and outcomes. RESULTS: Five patients (0.5%) underwent major amputation, including 3 transhumeral and 2 above-knee amputations. The median age was 37.8 years (interquartile range (IQR): 25.4-40.2), and 2 (40%) were male. Four (80%) patients had high-flow arteriovenous malformations, including 1 (20%) with Parkes-Weber syndrome. One (20%) patient had a low-flow venous malformation associated with Klippel-Trénaunay syndrome. All patients had malformation extending into the chest or pelvis, with the amputation being at the level of residual malformation. As such, amputation had been initially felt to be high risk because of the proximal extent of the lesions. Before amputation, a median of 11 procedures (IQR: 4-39) were performed per patient. This included 29 transarterial embolizations, 4 transvenous embolizations, 20 direct stick embolizations, 3 debulking procedures, 38 debridements, 6 skin grafts or muscle flaps, and 4 minor amputations. The median time course of treatment before amputation was 117 months (IQR: 44-171). Indications for major amputation included chronic pain and recurrent bleeding in all 5 (100%) patients, loss of function in 2 (40%), nonhealing wounds in 2 (40%), and sepsis in 1 (20%) patient. There were no perioperative deaths. The median blood loss was 1,000 mL (IQR: 650-2,750). All patients required transfusion of packed red blood cells with a mean of 1.6 units (standard deviation: 0.54). Transhumeral amputation was facilitated by transcatheter embolization in 1 (33%) and an occlusion balloon within the subclavian artery in 2 (66%) patients. The median length of stay was 6 days (IQR: 5-13). The median length of follow-up was 132 months (IQR: 68-186) from initial intervention and 12 months (IQR: 8-31) from amputation. Two patients (40%) who had undergone transhumeral amputation required revision of the amputation site for recurrent ulceration at 2 and 38 months. Of these, 1 patient underwent 3 transcatheter embolization procedures before revision and 1 underwent 1 embolization after revision. CONCLUSIONS: Although rare, successful amputation at the level of residual malformation can be performed in select patients with refractory complications of vascular malformations including intractable pain, bleeding, or nonhealing wounds. Specific preoperative and intraoperative measures may be critical to achieve satisfactory outcomes, and endovascular techniques continue to play a role after amputation.

A genetic screen for temperature-sensitive morphogenesis-defective Caenorhabditis elegans mutants.

Morphogenesis involves coordinated cell migrations and cell shape changes that generate tissues and organs, and organize the body plan. Cell adhesion and the cytoskeleton are important for executing morphogenesis, but their regulation remains poorly understood. As genes required for embryonic morphogenesis may have earlier roles in development, temperature-sensitive embryonic-lethal mutations are useful tools for investigating this process. From a collection of ∼200 such Caenorhabditis elegans mutants, we have identified 17 that have highly penetrant embryonic morphogenesis defects after upshifts from the permissive to the restrictive temperature, just prior to the cell shape changes that mediate elongation of the ovoid embryo into a vermiform larva. Using whole genome sequencing, we identified the causal mutations in seven affected genes. These include three genes that have roles in producing the extracellular matrix, which is known to affect the morphogenesis of epithelial tissues in multicellular organisms: the rib-1 and rib-2 genes encode glycosyltransferases, and the emb-9 gene encodes a collagen subunit. We also used live imaging to characterize epidermal cell shape dynamics in one mutant, or1219ts, and observed cell elongation defects during dorsal intercalation and ventral enclosure that may be responsible for the body elongation defects. These results indicate that our screen has identified factors that influence morphogenesis and provides a platform for advancing our understanding of this fundamental biological process.