Cryopreserved Cadaveric Arterial Allograft for Arterial Reconstruction in Patients with Prosthetic Infection

OBJECTIVE

The aim of this study was to report outcomes of cryopreserved arterial allografts used as a vascular substitute in the setting of prosthetic material infection.

METHODS

A retrospective analysis of prospectively collected data was conducted including all consecutive interventions performed with cryopreserved arterial allografts used for vascular reconstruction in the setting of prosthetic material infection between January 2005 and December 2014. Five year outcomes included allograft related re-interventions, survival, primary patency, and limb salvage rates.

RESULTS

Fifty-three procedures were performed using cryopreserved allografts for vascular prosthetic infection: 25 procedures (47%) were performed at aorto-iliac level (Group 1) and 28 procedures (53%) at peripheral level (Group 2). The mean follow-up was 52 months. Five year allograft related re-intervention was 55% in Group 1 (6 allograft ruptures and 5 allograft aneurysm degenerations) and 33% in Group 2 (2 allograft ruptures and 7 allograft aneurysm degenerations). Five year survival was 40% and 68%, primary patency was 89% and 59% and limb salvage was 100% and 89% for Group 1 and 2 respectively.

CONCLUSION

Use of cryopreserved arterial allografts provides acceptable results but is tempered by suboptimal 5 year outcomes with high re-intervention rates.

Moderate Exercise Allows for shorter Recovery Time in Critical Limb Ischemia

Whether and how moderate exercise might allow for accelerated limb recovery in chronic critical limb ischemia (CLI) remains to be determined. Chronic CLI was surgically induced in mice, and the effect of moderate exercise (training five times per week over a 3-week period) was investigated. Tissue damages and functional scores were assessed on the 4th, 6th, 10th, 20th, and 30th day after surgery. Mice were sacrificed 48 h after the last exercise session in order to assess muscle structure, mitochondrial respiration, calcium retention capacity, oxidative stress and transcript levels of genes encoding proteins controlling mitochondrial functions (PGC1α, PGC1β, NRF1) and anti-oxidant defenses markers (SOD1, SOD2, catalase). CLI resulted in tissue damages and impaired functional scores. Mitochondrial respiration and calcium retention capacity were decreased in the ischemic limb of the non-exercised group (V_max = 7.11 ± 1.14 vs. 9.86 ± 0.86 mmol 02/min/g dw, p < 0.001; CRC = 7.01 ± 0.97 vs. 11.96 ± 0.92 microM/mg dw, p < 0.001, respectively). Moderate exercise reduced tissue damages, improved functional scores, and restored mitochondrial respiration and calcium retention capacity in the ischemic limb (V_max = 9.75 ± 1.00 vs. 9.82 ± 0.68 mmol 02/min/g dw; CRC = 11.36 ± 1.33 vs. 12.01 ± 1.24 microM/mg dw, respectively). Exercise also enhanced the transcript levels of PGC1α, PGC1β, NRF1, as well as SOD1, SOD2, and catalase. Moderate exercise restores mitochondrial respiration and calcium retention capacity, and it has beneficial functional effects in chronic CLI, likely by stimulating reactive oxygen species-induced biogenesis and anti-oxidant defenses. These data support further development of exercise therapy even in advanced peripheral arterial disease.

Anatomical Study of Healthy Aortic Arches

BACKGROUND

With the steady increase of endovascular procedures involving the aortic arch (AA), an actual depiction of its anatomy has become mandatory. It has also become necessary to evaluate the natural evolution of the AA morphology as part of the evaluation of endovascular devices durability. The objective of this study was to perform a morphological and anatomical study of the AA and of the supra aortic trunks (SAT) in healthy patients, with an evaluation of their evolution with time, with a specific orientation applied to endovascular therapies of the AA.

METHODS

Sixty-one patients (31 men, mean age 50.8 [18-82]) with a normal anatomy were included in the study. Measurements included the diameters of the AA and SAT in 17 locations, their distance and angulation based on computed tomography angiography data. Statistical analysis focused on descriptive statistics, differences between genders, as well as correlations with age.

RESULTS

Aortic diameters (mean ± SD) were 29.5 ± 3.9 mm at the ascending aorta, 28.6 ± 3.9 mm at the innominate artery (IA), 27.1 ± 3.2 mm at the left common carotid artery (LCCA), 25.3 ± 3.0 mm at the left subclavian artery (LSCA), 23.9 ± 3.3 mm at the descending aorta. Mean angulation of the AA was 82° (95% confidence interval [CI]: 78.95-85.19°), mean angulation between LSCA/LCCA was -5.7° (95% CI: -0.9 to 18.7°) and -1.8° (95% CI: 5.4-26.4°) between LCCA/IA. Mean distance between the LSCA and the LCCA was 14.3 mm (95% CI: 13-15.6 mm) and 21.8 mm (95% CI: 20.3-23.4 mm) between LCCA and IA. All diameters of the AA increased with age (P < 0.05). Men had diameters statistically (P < 0.05) greater than women except at the LCCA ostium level. A statistically significant increase of the distances between the LSCA and the LCCA, between the LSCA and the IA and between the IA and the LCCA was found with age, P = 0.027, <0.01 and 0.012 respectively.

CONCLUSIONS

This study allows obtaining accurate information of the AA and the SAT anatomy. It enabled to obtain a better understanding of the three-dimensional aspects of the AA, confirmed the variability and heterogeneity of the SAT disposition, and discussed the principles of vascular aging.

Zenith Bifurcated Iliac Side Branch Device: Mid-term Results and Assessment of Risk Factors for Intraoperative Thrombosis

BACKGROUND

The aim of this study is to evaluate the short- and mid-term results of the Zenith bifurcated iliac side branch device (ZBIS) in the treatment of common iliac artery (CIA) aneurysms, and to assess risk factors for intraoperative internal iliac artery (IIA) thrombosis.

METHODS

All patients who underwent endovascular treatment of either an isolated CIA aneurysm or an aortoiliac aneurysm using the ZBIS device in the departments of vascular surgery of Strasbourg (France) and Lausanne (Switzerland) between January 2010 and December 2014 were retrospectively collected.

RESULTS

Thirty-one implantations were performed: 30 patients underwent 31 endovascular CIA aneurysm treatments with the ZBIS device. Mean operative time was 188 min. Technical success was obtained in 26 implantations (84%). In 5 implantations (16%), the final angiogram revealed an IIA thrombosis. Thirty-day mortality was 3.2%. Thirty-day morbidity was 13.3%. Mean follow-up was 15 months. Overall survival was 96% at 1 year and 89% at 2 years. In intention-to-treat analysis, primary patency of the internal iliac side branch was 84% at 1 year and 76% at 2 years (5 peroperative IIA occlusions and 1 late occlusion). Freedom from reintervention was 89% at 1 and 2 years. One case of type III endoleak and 2 cases of type II endoleaks were identified. Only type III endoleak required an additional intervention with a covered stent. Aneurysm diameter decreased in 15 implantations (48%) and remained stable in 16 implantations (52%). Clinical, radiological, and peroperative parameters were analyzed to identify risk factor for intraoperative thrombosis of the internal iliac side branch. Notion of intraoperative difficulties (any additional procedure that was not initially planned and increasing the operating time) appeared as a risk factor in multivariate analysis (P < 0.01, standard deviation 1.27, odds ratio 30.6).

CONCLUSIONS

The main findings of our study is that the procedure can be difficult to perform in particular conditions and can lead to peroperative failure in these cases, highlighting the need for adequate patients screening. When technical success is obtained, outcomes can be considered as satisfactory.

[Skeletal muscle ischemia-reperfusion and ischemic conditioning pathophysiology-clinical applications for the vascular surgeon]

Ischemia-reperfusion, which is characterized by deficient oxygen supply and subsequent restoration of blood flow, can cause irreversible damage to tissue. The vascular surgeon is daily faced with ischemia-reperfusion situations. Indeed, arterial clamping induces ischemia, followed by reperfusion when declamping. Mechanisms underlying ischemia-reperfusion injury are complex and multifactorial. Increases in cellular calcium and reactive oxygen species, initiated during ischemia and then amplified upon reperfusion are thought to be the main mediators of reperfusion injury. Mitochondrial dysfunction also plays an important role. Extensive research has focused on increasing skeletal muscle tolerance to ischemia-reperfusion injury, especially through the use of ischemic conditioning strategies. The purpose of this review is to focus on the cellular responses associated with ischemia-reperfusion, as well as to discuss the effects of ischemic conditioning strategies. This would help the vascular surgeon in daily practice, in order to try to improve surgical outcome in the setting of ischemia-reperfusion.

How can a vascular surgeon help in kidney transplantation

Kidney transplantation is a surgical procedure involving both vascular and ureteric anastomoses. As a matter of fact, it can be performed either by urologists or vascular surgeons. However, vascular surgeon's expertise can be helpful at different times. In the present paper we describe how can vascular surgeons help at the different stages of kidney transplantation process in modern care: 1) before kidney transplantation for recipient preparation in order to allow subsequent graft implantation, either by performing percutaneous embolization of renal arteries in the setting of polycystic kidney disease or treatment of aneurysmal or occlusive lesions that would contra-indicate graft implantation; 2) at the time of surgery graft back table preparation and repair; and 3) after surgery for long-term follow-up, including transplant renal artery stenosis treatment or transplant nephrectomy.

Systematic cervical approach for endovascular treatment of thoracic aortic diseases with debranching

Endovascular treatment of thoracic aorta (TEVAR) often requires supra-aortic arterial trunks debranching to provide an acceptable proximal landing zone. To facilitate TEVAR procedures involving landing zones 1 to 3, we propose a systematic 4-step strategy with 1) a primary surgical cervical exposure of the supra-aortic trunks; 2) insertion through this access of a 5 Fr introducer in the first non-covered supra-aortic trunk to delineate precisely the landing zone; 3) followed by deployment of the thoracic endograft through one femoral access; 4) immediate completion of the surgical debranching, i.e. transposition or bypass.

Cystic adventitial pathology as an entity in peripheral arterial disease

BACKGROUND

Cystic adventitial disease (CAD) is a rare condition in which mucinous cyst forms within the adventitia of arteries and veins. The management of CAD still remains unclear and a wide range of imaging and treatment options has been described. The purpose of this study is to propose an update of etiology, clinical diagnosis, imaging modalities and treatment options in the setting of CAD described on arterial territory.

METHODS

We performed a systematic review including studies reporting case or case series of CAD, searching across the Medline, Embase and Cochrane databases.

RESULTS

We identified 513 reports and 677 arterial cysts. Various imaging modalities such as Duplex ultrasonography, magnetic resonance imaging, computed tomographic angiography and conventional angiography were included. A wide range of treatment options have been performed with the most common being cyst resection followed by saphenous vein graft reconstruction in 259 cases. Follow-up was described in 431 cases with an average of 33 months. There were 51 patients who developed cyst recurrence. Among the 102 cases where joint connection was identified, 40 had either ligation of the joint connection or joint resection, which led to no recurrences.

CONCLUSIONS

CAD must be considered as en entity in peripheral arterial disease and considered in the differential diagnosis, in particular for middle-aged male patients who show no evidence of atherosclerotic disease. A better understanding of the pathogenesis of CAD will allow a consensus on treatment strategy and improve outcomes by reducing recurrence rates.

Vascular access complications in endovascular procedures with large sheaths

Endovascular procedures, such as transcatheter aortic valve implantation (TAVI), thoracic endovascular aortic repair (TEVAR), and endovascular abdominal aortic repair (EVAR) have been established as promising less invasive therapeutic options. However, despite continuous advances and device improvements, the use of large-sheaths still remains an important challenge, since significant coexisting arterial disease may be encountered in patients undergoing such procedures. Identification of coexisting arterial diseases by optimal preoperative imaging assessment is essential to anticipate these difficulties and avoid the complications by using adequate access options. Should a vascular complication such as iliac rupture occur, vascular interventionists must be aware of salvage procedures to control and treat major complications, such as maintaining wire access across the rupture for occlusion balloon placement and vessel control, while disruption is addressed either through an endovascular or an open approach. The aims of this review are to describe how to prevent vascular complications by optimal preoperative imaging assessment, to detail intraoperative options available for addressing difficult access issues and to discuss how to manage intraoperative major vascular complications.

Learning Curve of Robotic-Assisted Anastomosis: Shorter than the Laparoscopic Technique? An Educational Study

BACKGROUND

Achieving aortic anastomosis in laparoscopic surgery remains a technical challenge. The Da Vinci robot could theoretically counteract this issue by minimizing the technical challenge. The aim of this study was to compare the learning curves of performing vascular anastomoses by trainees without any experience using purely laparoscopic versus robotic-assisted techniques.

METHODS

Surgery residents were randomly included in the laparoscopic group (group A, n = 3) and the robotic group (group B, n = 3). They performed 10 end-to-end anastomoses on 18-mm-diameter tubular expanded polytetrafluoroethylene grafts. The parameters recorded were duration to complete the anastomosis and an indirect sealing quality evaluation (ISQE) defined as the following ratio: number of stitches with a distance of less than 4 mm/total number of stitches.

RESULTS

The mean duration to perform the anastomosis decreased from 2340 s (±64) for the first anastomosis to 651 s (±248) for the last in group A (P < 0.05) and from 1989 s (±556) to 801 s (±120) in group B (P < 0.05). The mean ISQE increased from 74% (±18) for the first anastomosis to 98% (±3) for the last in group A (P < 0.05) and decreased from 100% to 98% (±2) in group B (nonsignificant). The mean duration to perform the first anastomosis was lower in group B than in group A (P < 0.05). The mean duration to perform the last anastomosis was not significantly different between the groups. Sealing tended to be better in group B for the first anastomosis compared with group A.

CONCLUSIONS

Minimally invasive laparoscopic technique training demonstrates a learning curve to perform vascular anastomoses. The robotic-assisted technique tended to improve suturing skills and should be considered as a valuable tool to reduce the technical learning curve.

Promising Results of the Forearm Basilic Fistula Reveal a Worthwhile Option between Radial Cephalic and Brachial Fistula

BACKGROUND

Use of the forearm basilic vein for the creation of an arteriovenous fistula has been codified as second-choice vascular access for hemodialysis in the last clinical guidelines of the Society for Vascular Surgery in 2008. Poor literature data on this technical option and on its evaluation and outcomes led us to initiate a retrospective single-center study.

METHODS

We analyzed the outcomes of every arteriovenous fistula using the forearm basilic vein created in our department. It is a retrospective study in which we collected data prospectively by contacting dialysis centers, nephrologists, and patients. Primary end point was primary patency rate at 1 year. Secondary end points were secondary patency rate at 1 year, time of maturation, and Doppler flow measurement before the first puncture.

RESULTS

From February 2004 to June 2014, 49 forearm basilic arteriovenous fistulas were created: 33 ulnar-basilic and 16 radial basilic arteriovenous fistulas. Initial technical success rate was 98%. Functional success rate was 60%. Primary and secondary patency rates at 1 year were respectively 21% and 48%. Median time of maturation was 81 days, and mean Doppler flow measurement was 678 mL/min. Ulnar-basilic fistulas had a statistically significant shorter time of maturation than radial basilic fistulas (P ≤ 0.05).

CONCLUSIONS

Despite poor primary patency rate and a long time of maturation, forearm basilic arteriovenous fistula has satisfactory secondary patency rate and keeps all the advantages of a distal-located vascular access concerning complications. It is worth its second-choice place in the current algorithm of creation of vascular access for hemodialysis.

Results of isolated infrapopliteal percutaneous transluminal angioplasty for critical limb ischemia in high-risk diabetic patients

AIM

Infrapopliteal occlusive arterial lesions mostly characterize diabetic patients arteriopathy. Diabetic patients are prone to multiple comorbidities that make them candidates for low-invasive therapeutic options. The aim of this study was to evaluate the safety of infrapopliteal angioplasty in high-risk diabetic patients.

METHODS

We undertook a study (retrospective study of a prospectively collected database) of all infrapopliteal endovascular revascularizations performed for critical limb ischemia in high-risk (≥3 major comorbidities) diabetic patients in our institution between 2008 and 2010. Study end points were safety, technical success rate, healing rate, overall 1-year survival, primary patency, secondary patency and limb salvage rates.

RESULTS

A total of 101 high-risk diabetic patients (160 arterial lesions: 94 stenosis and 66 occlusions) underwent infrapopliteal endovascular surgery. No major adverse cardiovascular or cerebrovascular event was recorded within 30 days. Two major adverse limb events (two thromboses requiring major amputation) and seven minor adverse events were recorded. Technical and healing rates were, respectively, 83% and 78%. The 1-year survival, primary patency, secondary patency and limb salvage rates were, respectively, 86%, 67%, 83% and 84%.

CONCLUSION

Infrapopliteal angioplasty can be considered as a safe and feasible option for high-risk diabetic patients with critical limb ischemia.

A semi-automated image segmentation approach for computational fluid dynamics studies of aortic dissection

Computational studies of aortic hemodynamics require accurate and reproducible segmentation of the aortic tree from whole body, contrast enhanced CT images. Three methods were vetted for segmentation. A semi-automated approach that utilizes denoising, the extended maxima transform, and a minimal amount of manual segmentation was adopted.

[Contribution of mathematical models and biomechanical properties in predicting the risk of abdominal aortic aneurysm rupture]

INTRODUCTION

Rupture is the worst outcome of abdominal aortic aneurysm (AAA). The decision to operate should include counterbalancing the risk of aneurysm rupture against the risk of aneurysm repair, within the context of a patient's overall life expectancy. Current surgical guidelines are based on population studies, and important variables are missed in predicting individual risk of rupture.

METHODS

In this literature review, we focused on the contribution of biomechanical and mathematical models in predicting risk of AAA rupture.

RESULTS

Anatomical features as diameter asymmetry and lack of tortuosity are shown to be anatomical risk factors of rupture. Wall stiffness (due to modifications of elastin and collagen composition) and increased inflammatory response are also factors that affect the structural integrity of the AAA wall. Biomechanical studies showed that wall strength is lower in ruptured than non-ruptured AAA. Intra-luminal thrombus also has a big role to play in the occurrence of rupture. Current mathematical models allow more variables to be included in predicting individual risk of rupture.

CONCLUSION

Moving away from using maximal transverse diameter of the AAA as a unique predictive factor and instead including biological, structural and biomechanical variables in predicting individual risk of rupture will be essential in the future and will help gain precision and accuracy in surgical indications.