Extra-anatomic Bypass Grafting Research Articles

The anatomic repair of recurrent aortic arch obstruction in children and adolescents

ObjectiveSurgery for recurrent aortic arch obstruction is highly challenging and publications are rare. The aim of this retrospective, single-center study was to evaluate mortality, complications, and reintervention rate after an anatomic repair. MethodsBetween 1999 and 2022, in total 946 operations on the aortic arch were performed at the Children's Heart Center Linz. In 39 cases, the indication was a recurrent or residual aortic arch obstruction or coarctation in a patient aged 18 years or younger. This is our study cohort. The aorta was reconstructed by a direct anastomosis/autograft in 20 patients, patch in 17 patients, and interposition graft in 2 adolescents. In 32 procedures, cardiopulmonary bypass with whole body perfusion was employed, in 4, antegrade cerebral perfusion was employed, in 2, a left heart bypass was employed, and in 1 no cardiopulmonary bypass was used. ResultsMedian (Q1, Q3) age at operation was 253 days (100, 2198 days), weight 7.5 kg (4.5, 17.8 kg). Median cardiopulmonary bypass time was 177 minutes (115, 219 minutes), crossclamp time 73 minutes (49, 102 minutes). Three infants died during the hospital stay: 1 with Williams syndrome, 1 with hypoplastic left heart syndrome, and 1 with heterotaxia. There was no death due to an arch complication. The main complications were 1 neurologic injury after postoperative resuscitation (Williams syndrome) and 1 permanent recurrent laryngeal nerve paralysis. During the follow-up period of median 8.1 years (2.6, 12 years) 1 re-reintervention on the aortic arch was necessary. ConclusionsSophisticated reoperations on the aortic arch could be performed safely. In children, the growth potential of all segments of the aorta could be sustainably preserved by avoiding interposition or extra-anatomic bypass grafts.

Extra-anatomic bypass procedures for severe aortoiliac occlusive disease-A cohort study.

Extra-anatomic bypass (ExAB) grafting has been questioned due its inferior durability compared to anatomic bypass for aortoiliac occlusive disease (AIOD). This study aims to present early and late outcomes of patients treated with ExAB as well as to evaluate potential prognostic factors. This is a retrospective cohort study presenting a series of patients treated with ExAB for AIOD. All patients were treated between 2005 and 2022 within the Vascular Surgery Unit of a University Surgery Clinic. Both early (30-day) and late outcomes were evaluated. Univariate and multivariate analyses were conducted for potential predictors. Kaplan-Meier curve was produced for long-term patency. A total of 41 patients were treated (85.3% males; mean age: 76.3 ± 4.2years). Indication for treatment included severe claudication or critical limb ischemia (Rutherford stages III-VI). The following procedures were recorded: Femorofemoral bypass (FFB; n = 21) and axillofemoral bypass (AxFB; n = 20). All procedures were conducted using synthetic grafts with external rings. Early outcomes included no death, no myocardial infarction, no major bleeding, no graft infection, and no major amputation. Regarding late outcomes, 14.6% patients were lost after the first month. For the rest of patients (n = 35), five-year primary patency was 88.6%, primary-assisted patency was 94.3%, and secondary patency was also 94.3%. Limb salvage was 100% within follow-up. Endarterectomy at the distal anastomosis was the only independent predictor associated with worse patency in the long-term (OR = 5.356; 95% CI (1.012-185.562); p = .041). FFB and AxFB is a safe and durable strategy for treating patients with severe AIOD where no other option is feasible. Regarding predictors, only endarterectomy at the distal anastomosis site was associated with an increased risk for graft failure.

Coarctation Repair in an Adult Funambulist (Dombari)

Five to seven percent of all congenital cardiac disorders are caused by aortic coarctation. Funambulism or tight rope walking is a part of street circus acts earning livelihood for Dombari community, which requires utmost upper and lower limb strength and balance. Coarctation can be repaired surgically or with interventional approach. End-to-end anastomosis, subclavian flap aortoplasty, and extra-anatomic bypass grafts are a few surgical fixes. However, these approaches are not without risks involving the subclavian artery and spinal arteries thus putting limbs in jeopardy. Interventional procedures include balloon angioplasty and use of bare metal or covered stents but are associated with complications like repeated interventions or surgery, migration of stents compromising branches of aorta, thereby causing limb paresis or plegia, and are not very cost effective. The authors hereby discuss a cost-effective surgical management and spinal protection strategy for coarctation in a funambulist patient.

Dialister pneumosintes and aortic graft infection – a case report

BackgroundDialister pneumosintes is an anaerobic, Gram negative bacillus, found in the human oral cavity and associated with periodontitis. It has also been isolated from gastric mucosa and stool samples. Recent case reports implicate D. pneumosintes in local infection such as dental root canals, sinusitis, Lemierres syndrome and brain abscesses, as well as distal infections of the liver and lung through haematogenous spread.Case presentationWe present a novel case of aortic graft infection and aortoenteric fistula (AEF) in a 75 year old Caucasian male, associated with D. pneumosintes bacteraemia. Microbiological evaluation of septic emboli in the lower limbs revealed other gastrointestinal flora. This suggests either AEF leading to graft infection and subsequent distal emboli and bacteraemia, or a dental origin of infection which seeded to the graft, resulting in AEF and systemic infection. To our knowledge this is the first report of D. pneumosintes associated aortic graft infection. The patient underwent surgical explantation, oversew of the aorta and placement of extra-anatomical bypass graft in conjunction with antimicrobial therapy, making a good recovery with discharge home after a 35-day hospital admission.ConclusionWe report a case of Dialister pneumosintes bacteraemia associated with aortic graft infection. To our knowledge, vascular graft-associated infection with D. pneumosintes has not been reported before.

Successful surgical treatment of infected aorto-femoral­ bifurcation prosthesis by its explantation and bifurcation bypass grafting outside the area of previous reconstruction. Clinical case description

Vascular graft infections are associated with a significant risk of mortality and morbidity and cost approximately $640 million per year in the United States. Clinical pattern depends on the time elapsed since the implantation and surgery location. A thorough collection of medical history and physical examination in combination with various imaging methods are often necessary to confirm a diagnosis. There are several treatment options for infected aortic grafts, including graft excision with extra-anatomic bypass grafting, in situ reconstruction or neo-aortoiliac system reconstruction. The treatment of infected endovascular aortic grafts is similar. In cases of infected peripheral shunts, graft preservation techniques may be used, but if these are not feasible, graft removal and revascularization through uninfected tissues are necessary. The authors discuss the diagnosis, general management and surgical approaches to the treatment of infected vascular grafts, as well as a clinical case of successful surgical management of an infected aortofemoral bifurcation prosthesis by its explantation and bifurcation bypass grafting outside the area of previous reconstruction. Keywords: graft infection, reconstructive surgery, re-intervention

Open after endovascular repair for previous extra anatomic bypass of adult coarctation.

During follow-up, aneurysm formation in adults with coarctation of aorta has been reported after undergoing extra-anatomical aortic bypass grafting. Endovascular repair was a reasonable treatment option but there were still complications. A 48-year-old male who underwent extra-anatomical aortic bypass grafting, presented with severe back pain and hemoptysis. He had a diagnosed pseudoaneurysm with concealed rupture at the bypass grafting. He underwent endovascular repair and coil embolization. A postsurgical CT-angiogram showed there was extravasation from stent into the pseudoaneurysm. An open repair with endovascular stent removal instead of restenting was performed.

Right cervical aortic arch associated with anomaly of epiaortic vessels and haemodynamically significant obstruction between ascending and descending aorta. Extra-anatomic bypass graft between ascending and descending aorta and long-term follow-up.

Right cervical aortic arch is a rare malformation in which a right-sided aortic arch is unusually long, forms a loop, descends, and crosses behind the oesophagus to continue as a left descending aorta. We present a case of right cervical aortic arch associated with anomaly of epiaortic vessels and aortic obstruction, surgically treated with extra-anatomic bypass graft between ascending and descending aorta.

Outcomes Following in Situ Reconstruction for Aortic Infection with the Neo-Aortoiliac System and Aortic Homograft

In situ reconstruction is one of the primary surgical options for primary aortic and graft and endograft infections. One institution's outcomes following aortic reconstruction with femoro-popliteal vein (i.e., the neo-aortoiliac system) and cryopreserved aortic allografts are described. A retrospective review was performed of any patient who underwent aortic reconstruction with femoropopliteal vein or cryopreserved aortic allograft from 2013-2022 at a single tertiary-care institution. Twenty four patients underwent in situ reconstruction with the neo-aortoiliac system or with cadaveric allograft for primary or secondary aortic infection from 2013-2022. Short-term (30-day) mortality remains low (3/24 or 12.5%) despite the high incidence of major postoperative complications that necessitated reintervention in 11/24 or 45.8% of the cohort, most often for recurrent intracavitary infection. Gram-negative and drug-resistant pathogens were the most commonly implicated organisms in recurrent intra-abdominal infection. Management of early allograft degeneration is also described with extra-anatomic bypass grafting, conduit/graft embolization, which is then followed by allograft explantation and wide surgical debridement. Despite low short-term (30-day) mortality, all-cause 1-year mortality remains elevated at 38.1% (8/21) in those with an adequate follow-up interval. In situ reconstruction for primary or secondary aortic infections results in excellent short-term patient outcomes but is characterized by a high incidence of reintervention and an elevated all-cause 1-year mortality.

Extraanatomic bypass grafting in a patient with an infected femoral defect caused by a rollover accident: a case report

A 59-year-old male patient presented to the emergency department after a tractor rollover accident. His Injury Severity Score was 41 points. He had multiple pelvic bone fractures and a left common femoral artery injury with soft tissue loss. The injured arteries with skin defect were initially managed with endarterectomy and primary repair. However, the sepsis secondary to the infection from a skin defect became uncontrolled. The infected wound developed massive hemorrhage from the repaired arteries. Supportive measures were initiated to achieve hemostasis but unsuccessful. We performed an anastomosis with a prosthetic graft from the common iliac artery to the femoral artery above the knee, avoiding the wound through the lateral side of the anterior superior iliac spine. After revascularization, the patient recovered uneventfully. An extraanatomic graft reconstruction should be considered early when the autologous vein is unsuitable.

Management for lower limb malperfusion in acute type a aortic dissection patients.

Acute type A aortic dissection (ATAAD) accompanied with lower limb malperfusion (LLM) is considered to be a catastrophic event, and remains a great challenge for cardiac surgeons. Here we introduce our experience in treating ATAAD patients accompanied with LLM. 61 patients diagnosed with ATAAD accompanied by LLM enrolled in this study. All patients received aortic repair (Total-arch replacement or Hemi-arch replacement) as soon as possible on admission. Patients who still suffered LLM were performed extra-anatomic bypass using artificial vessels. All the discharged patients underwent the standard follow-up protocol. 38 patients (38/61, 62.3%) got satisfied reperfusion of the lower limbs after aortic repair while the others did not. Five patients had femorofemoral bypass, 16 received aortofemoral bypass, and two underwent aortofemoral bypass plus femorofemoral bypass. The ICU stay time was 5.4 ± 3.6days. Fifty-five patients were discharged home successfully, while six patients died postoperatively with hospital mortality of 9.8%. Major postoperative complications included acute kidney injury requiring hemodialysis in seven patients, delayed wake-up (>3days) in 5, prolonged ventilation (>4days) in 8, and lower limb ischaemia in 1. Follow-up was successfully conducted in 50 patients with a mean follow-up time 4.9 ± 2.6years. Five patients died during the follow-up. The estimated 5-year survival rate was 87.5 ± 6.1%. CTA images showed 100% patency of the extra-anatomic bypass. Aortic repair plus concomitant extra-anatomic bypass grafting in one operative setting could be a simple, safe and effective treatment on ATAAD patients with LLM.

Impact of extra-anatomical bypass on coarctation fluid dynamics using patient-specific lumped parameter and Lattice Boltzmann modeling

Accurate hemodynamic analysis is not only crucial for successful diagnosis of coarctation of the aorta (COA), but intervention decisions also rely on the hemodynamics assessment in both pre and post intervention states to minimize patient risks. Despite ongoing advances in surgical techniques for COA treatments, the impacts of extra-anatomic bypass grafting, a surgical technique to treat COA, on the aorta are not always benign. Our objective was to investigate the impact of bypass grafting on aortic hemodynamics. We investigated the impact of bypass grafting on aortic hemodynamics using a patient-specific computational-mechanics framework in three patients with COA who underwent bypass grafting. Our results describe that bypass grafting improved some hemodynamic metrics while worsened the others: (1) Doppler pressure gradient improved (decreased) in all patients; (2) Bypass graft did not reduce the flow rate substantially through the COA; (3) Systemic arterial compliance increased in patients #1 and 3 and didn’t change (improve) in patient 3; (4) Hypertension got worse in all patients; (5) The flow velocity magnitude improved (reduced) in patient 2 and 3 but did not improve significantly in patient 1; (6) There were elevated velocity magnitude, persistence of vortical flow structure, elevated turbulence characteristics, and elevated wall shear stress at the bypass graft junctions in all patients. We concluded that bypass graft may lead to pseudoaneurysm formation and potential aortic rupture as well as intimal hyperplasia due to the persistent abnormal and irregular aortic hemodynamics in some patients. Moreover, post-intervention, exposures of endothelial cells to high shear stress may lead to arterial remodeling, aneurysm, and rupture.

Abstract No. 122 Endovascular treatment of extra-anatomic bypass graft thrombosis

Abstract No. 122 Endovascular treatment of extra-anatomic bypass graft thrombosis

Repair of pseudoaneurysm in extra-anatomic aortic arch bypass graft.

Repair of pseudoaneurysm in extra-anatomic aortic arch bypass graft.

Aortoaortic bypass after ineffective extra anatomic bypass grafting for disabling claudication due middle aortic syndrome

Middle aortic syndrome is a coarctation of the distal thoracic and/or abdominal aorta seen in 0.5% to 2.0% of the general population and believed to be the result of a congenital abnormality, granulomatis vasculitis or von Recklinghausen disease. Treatment is often indicated because of renal hypertension or claudication, or, both and has been advocated during the “burn-out” stage in patients with vasculitis.1-3

Descending aortic transection for recurrence of a pseudoaneurysm previously treated with a stent graft after extra-anatomical bypass for aortic coarctation: a case report

BackgroundIn adult patients with primary or recurrent coarctation of the aorta (CoA), extra-anatomic bypass grafting (EABG) has been widely used as a surgical treatment option. However, there have been few reports on pseudoaneurysms (PAs) of the distal anastomotic sites after extra-anatomic bypass for CoA.Case presentationA 51-year-old man with hemoptysis was transferred to our hospital. Twenty years ago, he had undergone EABG from the ascending to the descending aorta (ascending-to-descending EABG) for CoA with right aortic arch. Eight years ago, he underwent thoracic endovascular aortic repair (TEVAR) for the ruptured PA on the distal anastomotic site of the EABG. Contrast-enhanced computed tomography scans revealed recurrent ruptured PA on the distal anastomotic site of the EABG. Therefore, we decided to replace the descending aorta, followed by end-to-side anastomosis of the EABG to the replaced descending aorta. However, due to massive adhesion of the lung to the EABG and PA, we performed transection of the descending aorta to decompress the PA. The postoperative course was uneventful, and the patient is doing well 5 months after surgery.ConclusionsAortic transection between the CoA and the distal anastomosis site may be a useful additional procedure in patients previously treated with TEVAR for PAs in the distal anastomosis site after EABG.

Graft-renal bypass surgery during intraoperative dissection of renal artery in a patient with high occlusion of the aorta

Despite advances in the development of endovascular techniques of revascularization of renal arteries, in certain clinical cases still remains the need to perform extra-anatomic renal bypass grafting. To such instances belong complicated atherosclerotic aortic lesions, technical difficulties occurring during open revascularization of the aorta and its branches, as well as aneurysms of the juxtarenal portion of the abdominal aorta. Presented herein is a clinical case concerning a patient subjected to non-standard restoration of blood flow in the right renal artery after thromboendarterectomy from the juxtarenal aorta, performed from the left-sided extraperitoneal phrenolumbotomic approach and complicated by secondary dissection of the intima in the right renal artery.

Comparison of Physician-Modified Fenestrated/Branched Stent-Grafts and Hybrid Visceral Debranching Plus Stent-Graft Placement for Complex Thoracoabdominal Aortic Aneurysm Repair

Purpose: To evaluate the immediate postoperative and midterm outcomes of complex thoracoabdominal aortic aneurysm (TAAA) treatment with fenestrated/branched physician-modified endovascular grafts (PMEGs) or open debranching of the visceral aorta with bypass graft revascularization plus endovascular aneurysm exclusion (hybrid repair). Materials and Methods: A retrospective analysis was conducted of 88 patients (mean age 70.0±10.6 years; 73 men) with complex TAAAs who underwent treatment with PMEGs (60, 68%) or a hybrid technique (28, 32%) between 2016 and 2019. The mean aneurysm diameter was 64.5±11.7 mm, and 37 patients (42%) were symptomatic. The Zenith TX2 and Ankura were the main stent-grafts used in the PMEG group. The hybrid technique involved visceral debranching with extra-anatomical bypass graft revascularization and subsequent stent-graft deployment (1- or 2-stage procedure). Results: In the PMEG group, 35 patients received modified stent-grafts with 4 fenestrations, 8 patients had 4 branches per device, and 17 patients had combinations (50 fenestrations and 18 branches) that successfully revascularized 228 of the 240 targets (95%). In the 28 hybrid cases, all 110 target vessels were successfully revascularized with bypass grafts. The overall 30-day mortality was 3.4% (2 PMEG and 1 hybrid), and the early rate of target vessel stenosis/occlusion was 3.3% (5 in PMEG group and 6 in the hybrid repair group). The 30-day morbidity was mainly attributed to pulmonary complications (15%), lower limb ischemia (8%), or spinal cord ischemia with paraplegia (6%). Eleven patients (13%) had deteriorated renal function with a >30% decrease in the glomerular filtration rate. The mean follow-up was 22.3±4.9 months, and mortality was 4.5% (3.3% in the PMEG group vs 7.1% in the hybrid repair group). Conclusion: PMEGs and hybrid techniques seem to be feasible treatment options for aortic aneurysms necessitating visceral vessel revascularization. PMEGs may have a lower morbidity than the hybrid technique, which nonetheless remains an important option available for complex aortic aneurysms.

Selective Use of Anticoagulation or Dual Antiplatelet Therapy for Patients with Extra-anatomic Bypasses

The benefit of long-term anticoagulation or dual antiplatelet therapy (DAPT) for patients with extra-anatomic bypasses to the lower extremity remains poorly defined. Our study analyzed the real-world use of antithrombotic therapy in patients with extra-anatomic bypass grafts to the lower extremity and compared graft and patient outcomes by antithrombotic regimen. We studied patients who underwent axillofemoral or femoral-femoral bypass within the Vascular Quality Initiative with one-year follow-up data. Primary exposures were anticoagulation and DAPT, at the time of index procedure and one-year follow-up. Primary outcomes were major adverse limb events (MALE) defined as reintervention or above-ankle amputation, and primary patency. Secondary outcomes included perioperative blood transfusion requirements and the need for reoperation specifically for bleeding. We analyzed outcomes using the Kaplan-Meier estimation and examined factors associated with choice of antithrombotic therapy via logistic regression. Our cohort included 2,760 patients (axillofemoral bypass, n=857; femoral-femoral bypass, n=1,903) across 168 centers from 2009 to 2018. Mean age was 66.5±10.5years and 59% were male. Patients were infrequently prescribed long-term anticoagulation (19%) or DAPT (22%). One-year primary patency was 86% and was similar by anticoagulation (log-rank P=0.12) and DAPT status (log-rank P=0.26). Freedom from MALE was 87% at 1year and was slightly inferior for patients on anticoagulation (88 vs. 83%, log-rank P=0.001) but was similar by DAPT (log-rank P=0.19). Transfusion was more common in patients who were anticoagulated than those who were not (30 vs. 25%, P<0.01), but there was no increase in reoperation because of bleeding (anticoagulation 0.8 vs. 0.8, P=0.98). Anticoagulation was more commonly prescribed according to disease severity, such as rest pain (adjusted odds ratio (OR): 1.6 (95% confidence interval (CI): 1.20-2.20), tissue loss (OR: 1.9, CI: 1.28-2.73), or acute limb ischemia (OR: 1.9, CI: 1.35-2.71) or prior bypass graft (OR: 2.6, CI: 2.07-3.35). Patients were more commonly prescribed DAPT according to comorbidities, including hypertension (OR: 1.4, CI: 1.04-1.94) and coronary artery disease (OR: 1.6, CI 1.26-1.95). Antithrombotics are selectively used in patients with extra-anatomic bypass to the lower extremity, the selection of which appears associated with disease severity for anticoagulants and patient comorbidities for DAPT. Primary patency and MALE rates are similar with focused utilization of anticoagulants or DAPT. Blood transfusions are more common among patients on antithrombotics without a difference in the need for reoperation for bleeding.

Surgical management of Coarctation of the Aorta in the Pediatric Population: A fifteen-year experience

Coarctation of the aorta is one of the most commonly encountered congenital heart defects (CHD), in the pediatric population. It is defined as a hemodynamically significant stenosis of the descending aorta, typically at the site of insertion of ductus arteriosus. It has an estimated incidence of 4-6 cases per 100,000 births, accounting for 5-8% of all congenital heart defects [1-4]. According to The New England Regional Infant Cardiac Program (NERICP), coarctation of the aorta is the fourth most common defect requiring surgery during the first year of life [5]. It can present as an isolated lesion or coexist with other cardiac or extra-cardiac congenital defects. The most common one include bicuspid aortic valve, patent ductus arteriosus, ventricular septal defect, mitral stenosis, berry aneurysms in the circle of Willis [6-8]. Clinical presentation is heterogenous, varying from asymptomatic to congestive heart failure, acute pulmonary edema and cardiogenic shock, depending on the degree of coarctation, the development of collateral circulation and age at presentation [9]. During the neonatal period patients may present with circulatory collapse and pulmonary edema, reduced or absent peripheral pulses, tachypnea, lethargy and progressive metabolic acidosis [9-13]. In early childhood, they present primarily with symptoms of congestive heart failure (CHF) including tachypnea, irritability, sweating, feeding difficulties and failure to thrive [9-13]. In adolescence and adulthood patients may be asymptomatic, presenting with non-specific symptoms including exercise intolerance, fatigue and cramps in the lower limbs, recurrent headaches, epistaxis, vertigo, tinnitus, high blood pressure and difference in blood pressure between arms and legs and reduced or absent peripheral pulses [9-13]. Treatment options for coarctation of the aorta include both surgery and catheter-based procedures. Several surgical techniques have been developed including extended resection with end-to-end anastomosis, prosthetic patch aortoplasty, subclavian patch aortoplasty, interposition grafting and extraanatomic bypass grafting [9-11,13-18]. Catheter-based approaches include balloon angioplasty and stenting. The choice is based on the age at presentation, the type of coarctation, and the presence of associated anomalies, as well as other patient-specific characteristics.

Central venous occlusion in dialysis patients – Novel surgical management

Introduction: The progress in the management of maintenance hemodialysis and renal transplant has led to longer survival and also increased incidence of delayed complications. One of its dreadful complications is central venous occlusion which needs a satisfactory management. Materials and Methods: Bilateral subclavian vein occlusion, innominate vein occlusion, or superior vena cava occlusion remains the most dreadful scenario for central venous stenosis and central venous obstruction (CVO) in dialysis patients. In these patients who are refractory to endovascular options, surgery must be considered. We hereby describe our experience of managing these complications by a novel surgery of draining the area proximal to CVO to the right atrium by reinforced Polytetrafluoroethylene graft. Results: Three of our patient's symptom relief, salvage of arteriovenous fistula, and primary graft patency (mean – 20 months) were achieved satisfactorily. No postoperative mortality or no severe morbidity noted. Anticoagulation orally used up to 3 months of operation. One patient had graft occlusion and mild symptom recurrence. Conclusions: All the current endovascular options for CVO in dialysis patients are prone to recur. Extra-anatomic central venous bypass grafting draining into right atrial appendage is a novel management to relieve the complications. A satisfactory conduit with long-term patency and minimum thrombotic complications is still not available. Randomized control trials with long-term follow-up are needed to develop appropriate treatment algorithms.