Stefano Bonvini

Prospective, randomized study of external jugular vein patch versus polytetrafluoroethylene patch during carotid endarterectomy: perioperative and long-term results

OBJECTIVES The purpose of this study was to evaluate the relative risks and advantages of using external jugular vein (EJV) patch, compared with polytetrafluoroethylene (PTFE) patch, during carotid endarterectomy. The primary end point was the relevant neurologic complication rate (RNCR; fatal or disabling stroke) at any time during follow-up. Secondary end points included stroke-free survival, 30-day and long-term mortality, recurrent stenosis rate (> or =50%), occlusion, patch infection, aneurysm formation, and other local complications. METHODS The study, a prospective randomized clinical trial carried out at a single center, was divided into two 3-year phases: December 1996 to March 1999, when patients were enrolled, and March 1999 to March 2002, which was the follow-up period. Inclusion criteria included an external jugular vein suitable for patching, defined as vein diameter 3 mm or larger and absence of collateral vessels noted on preoperative color duplex ultrasound scans. Patients were prospectively randomized 1:1 to receive either the EJV (n = 80; group A) or synthetic (n = 80; group B) patch. RESULTS Carotid endarterectomy and patching was performed by one surgeon. At 30 months the RNCR-free rate, analyzed with the Kaplan-Meier method, was 98.7% for group A (1 ipsilateral lethal stroke) and 94.6% for group B (4 ipsilateral disabling strokes), and remained stable to 60 months. No statistical difference was observed with the log-rank test. Stroke-free survival rate was 100% for group A and 98.7% for group B at 1 year, 98.7% for group A and 93.6% for group B (1 ipsilateral minor stroke) at 30 months, and was unchanged at 60 months. Life table analysis demonstrated freedom from significant recurrent stenosis (> or =50%) of 97.5% for both groups at 6 months, 93.6% for group A and 92.2% for group B at 30 months, and 90.2% for group A and 86.7% for group B at 60 months. No statistical difference was observed with the log-rank test. In no patients was recurrent stenosis greater than 70%. No aneurysm formation was noted during follow-up. CONCLUSIONS We can conclude, with the power limitation of the study, that carotid endarterectomy can be safely performed with either the EJV or PTFE patch. Advantages of the EJV for carotid angioplasty include no cost for material, low risk for graft infection, and preservation of the saphenous vein.

Synchronous carotid endarterectomy and retrograde endovascular treatment of brachiocephalic or common carotid artery stenosis.

OBJECTIVES To retrospectively evaluate the safety and the long-term results of retrograde brachiocephalic and common carotid angioplasty and stenting (AS) performed for >70% stenosis synchronously with the carotid endarterectomy (CEA). PATIENTS Sixteen patients operated between April 1999 and March 2002. RESULTS 14/16 procedures were successful. There was no neurological morbidity or mortality. Per-operative angiography showed the optimal stent positioning and patency of both proximal and distal arteries in all patients. In the follow-up, all patients showed patency of the treated vessels without restenosis and the absence of any cerebrovascular symptoms. CONCLUSION Intra-operative retrograde AS combined with CEA is an effective, safe and durable alternative to conventional surgery when a tandem significant proximal lesion is identified in a patient with an high grade carotid stenosis.

Role of aneurysm sac embolization during endovascular aneurysm repair in the prevention of type II endoleak-related complications

OBJECTIVE The goal of this study was to evaluate the role of intraoperative aneurysm sac embolization during endovascular aneurysm repair (EVAR) using a standard dose of coils and fibrin glue in the prevention of type II endoleak (EII). METHODS Two groups were compared: 83 patients underwent standard EVAR during the period 2008-2009 (group A) and 79 patients underwent EVAR during the period 2010-2011 (group B). Computed tomography scans were evaluated with Osirix Pro 4.0 software to obtain aneurysm sac volume. EII rates at the first computed tomography scan follow-up, as well as midterm freedom from EII and freedom from related reintervention, were compared. Preoperative number of patent aortic side branches (inferior mesenteric artery, lumbar arteries, accessory renal arteries), sac thrombus, and sac volume were evaluated for their association with EII in the two groups using multiple logistic regressions. RESULTS Patient characteristics, Society for Vascular Surgery comorbidity scores (0.85 ± 0.44 vs 0.82 ± 0.46; P = .96), and operative time (185 ± 52 vs 179 ± 49; P = .92) were similar for groups A and B. The first computed tomography scan (≤3 months) revealed a significantly larger number of EIIs in group A than in group B (23% vs 10%; P = .02). Spontaneous EII resolution occurred in 65% of patients in group A and in 79% in group B (P = 1.0), whereas sac volume increased in 25% and 10% (P = .63) of cases, respectively. At 18 months (range, 6 months to 4.4 years), overall mean differences in sac volume shrinkage (27 ± 12 cm(3) vs 25 ± 12 cm(3); P = .19) and freedom from EII (92% vs 96%; P = .33) were similar, whereas freedom from reintervention was significantly lower in group A (93% vs 99%; P = .03) than in group B. Multivariate analysis showed preoperative aneurysm sac volume >125 cm(3) to be the only independent significant predictor of EII (odds ratio, 4.0; 95% confidence interval, 1.5-10.5; P = .005). CONCLUSIONS Although further confirmatory studies are needed, sac embolization during EVAR may be a valid approach to preventing EII and its complications during short- and midterm follow-up. More aggressive intraoperative embolization should be considered for patients with a preoperative aneurysm sac volume >125 cm(3).

Long Term Outcomes and Sac Volume Shrinkage After Endovascular Popliteal Artery Aneurysm Repair

OBJECTIVES The aim was to evaluate long-term outcomes and sac volume shrinkage after endovascular popliteal artery aneurysm repair (EVPAR). METHODS This study was a retrospective review of all EVPAR cases between 1999 and 2012. Sac volume shrinkage, long-term patency, limb salvage, and survival were evaluated using Kaplan-Meier estimates. The association of anatomical and clinical characteristics with patency was evaluated using multivariate analysis. RESULTS Forty-six EVPAR were carried out in 42 patients (mean age 78 years, 86% male; mean sac volume 45.5 ± 3.5 mL). In 93% of cases (n = 43) the procedure was elective, while in 7% of cases it was for rupture (n = 2) or acute thrombosis (n = 1). Of the 43 patients who underwent elective repair, 58% were asymptomatic and 42% symptomatic (14 claudication, 3 rest pain, and 1 compression symptoms). Technical success was 98%. Mean duration of follow-up was 56 ± 21 months. Primary patency at 1, 3, and 5 years was 82% (SE 2), 79% (SE 4), and 76% (SE 4), while secondary patency was 90% (SE 5), 85% (SE 4), and 82% (SE 1) respectively; at 5 years there was 98% limb salvage and an 84% survival rate. During follow-up 11 limbs had stent graft failure: six required conversion, one underwent amputation, and four continued with mild claudication. Of those with graft failure, 63% (7/11) occurred within the first year of follow-up. The mean aneurysm sac volume shrinkage between preoperative and 5-year post-procedure measurement was significant (45.5 ± 3.5 mL vs. 23.0 ± 5.0 mL; p < .001). Segment coverage >20 cm was a negative predictor for patency (HR 2.76; 95% CI 0.23; p = .032). CONCLUSIONS EVPAR provides successful aneurysm exclusion with good long-term patency, excellent limb salvage, and survival rates. Close surveillance is nevertheless required, particularly during the first postoperative year. Patients requiring long segment coverage (>20 cm) may be at increased risk for failure.

ViPS technique as a novel concept for a sutureless vascular anastomosis

OBJECTIVE To describe a novel technique (Viabhan Padova Sutureless [ViPS]) that connects a vascular prosthetic graft to a target artery in a sutureless fashion. METHODS The patient was a 74-year-old male with complete superficial femoral artery (FA) occlusion and reconstitution of a circumferentially calcified above-knee popliteal artery (ANPA). The proximal end of a surgeon-modified 7-mm Viabahn endoprosthesis was sutured to a 7-mm polytetrafluoroethylene graft (PTFEg). After surgical exposure, the ANPA was transected, and the undeployed distal portion of the Viabahn was inserted, supported by a stiff guidewire. The distal portion of the Viabahn graft was then deployed and ballooned with optimal apposition. Finally, the proximal end of the PTFEg was sutured to the common FA. RESULTS Operative time was 60 minutes. Completion angiogram and the computed tomography angiogram at 6 months demonstrated a patent graft. CONCLUSION The ViPS technique provides an alternative for bypass creation when challenging arterial anastomoses are required.

The Peritoneum as a Natural Scaffold for Vascular Regeneration

Objective The peritoneum has the same developmental origin as blood vessels, is highly reactive and poorly thrombogenic. We hypothesize that parietal peritoneum can sustain development and regeneration of new vessels. Methods and Results The study comprised two experimental approaches. First, to test surgical feasibility and efficacy of the peritoneal vascular autograft, we set up an autologous transplantation procedure in pigs, where a tubularized parietal peritoneal graft was covered with a metal mesh and anastomosed end-to-end in the infrarenal aorta. Second, to dissect the contribution of graft vs host cells to the newly developed vessel wall, we performed human-to-rat peritoneal patch grafting in the abdominal aorta and examined the origin of endothelial and smooth muscle cells. In pig experiments, the graft remodeled to an apparently normal blood vessel, without thrombosis. Histology confirmed arterialization of the graft with complete endothelial coverage and neointimal hyperplasia in the absence of erosion, inflammation or thrombosis. In rats, immunostaining for human mitochondri revealed that endothelial cells and smooth muscle cells rarely were of human origin. Remodeling of the graft was mainly attributable to local cells with no clear evidence of c-kit+ endothelial progenitor cells or c-kit+ resident perivascular progenitor cells. Conclusions The parietal peritoneum can be feasibly used as a scaffold to sustain the regeneration of blood vessels, which appears to occur through the contribution of host-derived resident mature cells.

Aortic hybrid sutureless anastomosis on porcelain aorta.

Purpose: To describe a hybrid sutureless anastomosis technique between a prosthetic graft, an endograft, and a circumferentially calcified infrarenal aorta. Technique: The technique is demonstrated in a 65-year-old man with flush distal aortoiliac occlusion and patent infrarenal porcelain aorta (IPA). After laparotomy, the IPA was occluded below the renal arteries by inflating an aortic balloon introduced via an axillary access. The IPA was transected in its distal part and aortic thrombectomy performed. A Zenith iliac extension was modified on a back table by cutting the terminal tip; the device was then was inserted and deployed into the IPA in a standard fashion and the sheath removed. A Dacron bifurcated graft was sutured in an end-to-end anastomosis to the endograft and terminal aorta. The 12-month computed tomography scan showed patency of the graft. Conclusions: This sutureless anastomosis technique seems safe and feasible and represents a valid alternative to standard surgical approaches in cases of heavy and circumferentially calcified infrarenal aorta.

Modification of the Viabahn Padova Sutureless Technique for Challenging Anastomosis Between a Prosthetic Graft and a Circumferentially Calcified Target Artery

Purpose To describe modification of the Viabahn Padova Sutureless (ViPS) technique for challenging anastomosis between a prosthetic graft and a circumferentially calcified target artery. Technique The technique is demonstrated in a 75-year-old man with complete superficial femoral artery (SFA) occlusion and reconstitution of a circumferentially calcified above-knee popliteal artery. A 7-mm Viabahn endoprosthesis with its constraining string was withdrawn from its delivery system; the string at the proximal edge of the stent was gently cut with a scalpel, causing the proximal part of the stent to deploy, while the undeployed distal tip with its smooth profile retained its commercial orientation. The proximal end was subsequently sutured to a 7-mm polytetrafluoroethylene (PTFE) graft. After surgical exposure, the popliteal artery was transected, and the undeployed distal portion of the Viabahn was inserted into the distal segment, supported by a stiff guidewire. By pulling the constraining string, the stent was deployed in a “non-reversed” fashion and subsequently dilated to achieve optimal apposition. Finally, the proximal end of the PTFE graft was tunneled under the sartorius muscle and sutured to the common femoral artery. Conclusion This modification to the ViPS technique using a “non-reversed” method of Viabahn stent preparation allows a safer and more accurate deployment of the endoprosthesis in the calcified target artery.

Use of a Thoracic Endograft in an Acute Abdominal Aortic Setting: Case Report and Literature Review.

Purpose: We report the case of a thoracic endograft used to achieve exclusion of a ruptured proximal paranastomotic abdominal aortic aneurysm (PAAA) as a consequence of aortic ballooning. Case Report: A type I proximal endoleak was evidenced following endovascular repair of a PAAA with an aortic cuff. The leak was treated with ballooning, which caused distal aortic rupture. A thoracic endograft was deployed inside the cuff, achieving complete exclusion. At 1 year, there are no signs of migration or endoleak with complete PAAA thrombosis, according to computed tomographic angiography. Conclusion: In hostile proximal abdominal aortic neck, challenging anatomies, or urgent cases, the structural adaptability of thoracic endografts could provide safe and successful abdominal aortic endovascular exclusion.

Systemic Inflammatory Response and Severe Thrombocytopenia after Endovascular Thoracic Aortic Aneurysm Repair

After Endovascular repair of thoracic aortic aneurysm, a systemic inflammatory response, named postimplantation syndrome, can develop. This syndrome is characterized by fever, leukocytosis, and elevated CRP plasma levels and its pathogenetic mechanisms are still unknown. Although this syndrome generally resolves within few days, some patients develop a persisting severe inflammatory reaction leading to mild or severe complications. Here we describe the case of a male patient who developed postimplantation inflammatory syndrome and severe thrombocytopenia after endovascular repair of thoracic aortic aneurysm. Treatment with prednisone (50 mg/bid) for two weeks did not improve the clinical and laboratory findings. We utilized danazol, a weak androgen that has been shown to be effective in the treatment of immune and idiopathic thrombocytopenic purpura, and after 12 days of treatment with danazol (200 mg/bid), the patient improved progressively and platelet number increased up to 53,000/μL. Patients undergoing endovascular repair of thoracic aortic aneurysm should be carefully monitored for the development of postimplantation syndrome. This clinical condition is relatively common after the endovascular repair of aortic aneurysm but is rarely observed after endovascular repair of thoracic aortic aneurysms. The different known therapeutical approaches are still empiric, with reported beneficial effects with the use of NSAID, corticosteroids, and danazol.