Pierre-Edouard Magnan

Effects of cryopreservation on the viscoelastic properties of human arteries.

The purpose of this study was to use our newly developed mock circulation loop to determine the effects of cryopreservation on the common carotid artery (CCA) and the superficial femoral artery (SFA). Fourteen healthy arteries (7 CCA and 7 SFA) harvested from multiple organ donors between the ages of 18 and 35 years were tested before and after cryopreservation at −140° C using dimethyl sulfoxide and the vapor phase of liquid nitrogen. Mean storage time was 4.2 months. The mock pulse rate was 60 beats/min and the following four systolic/diastolic pressures settings were used: 50/110, 80/140, 110/170, and 140/200 mm Hg. Simultaneous measurements of intra-arterial pressure and external arterial diameter were made using an intra-arterial pressure sensor and external piezoelectric sensors. Measured data were used to calculate pulsatility, volumetric compliance, stiffness, midwall radial arterial stress, Youngs modulus, and the incremental modulus. After SFA cryopreservation, no significant changes were observed. Conversely, CCA cryopreservation led to a significant decrease in compliance and pulsatility and a significant increase in stiffness. Youngs modulus, the incremental modulus, and midwall radial arterial stress did not change significantly. A clearcut decrease in hysteresis was observed after cryopreservation in the CCA. No evidence of structural changes was detected on light and scanning electron microscopy. Baseline findings in this study were consistent with classification of the CCA as an elastic artery and the SFA as a muscular artery. Cryopreservation had no effect on the viscoelastic properties of muscular arteries (SFA). Cryopreservation affected only values related to the cylindrical shape of the elastic arteries (CCA). It had no effect on values related to wall structure.

Pelvic ischemia and quality of life scores after interventional occlusion of the hypogastric artery in patients undergoing endovascular aortic aneurysm repair

OBJECTIVE The aim of this study was to analyze the pelvic ischemic complications and their impact on quality of life after interventional occlusion of the hypogastric artery (IOHA) in patients undergoing endovascular aortic aneurysm repair (EVAR). METHODS Between January 2004 and April 2012, 638 consecutive patients with aortoiliac aneurysm treated by EVAR were prospectively registered in two teaching hospitals. We identified all EVAR patients who underwent IOHA. Demographic, clinical, and radiologic data were extracted from electronic databases and patient records as requested. All patients who survived the postoperative period took part in a quality of life survey, the Walking Impairment Questionnaire (WIQ), which included four items: pain, distance, walking speed, and stair climbing. Outcome measures included the 30-day rate of pelvic ischemic complications, the buttock claudication (BC) rate at 30 days and during follow-up, and the comparative WIQ scores between patients with persistent BC, those with regressive BC, and those who never had BC after the IOHA procedure. RESULTS A total of 71 patients (97% men; mean age, 76 years ± 7.69) required 75 IOHA procedures. These were deemed proximal in 44 cases and distal in 31, with use of coil embolization in 64%, Amplatzer plug in 24%, or a combination of coils and plugs in 12%. The technical success rate was 100%. Two patients (2.8%) experienced fatal acute pelvic ischemic complications in the postoperative period after EVAR. Another patient died of iliac rupture during EVAR, leading to an operative mortality rate of 4.3%. Eighteen patients (25.3%) suffered BC, among whom 11 cases resolved at a median follow-up of 42 months. Young age (odds ratio, 0.92; 95% confidence interval, 0.85-0.99; P = .03) and distal IOHA (odds ratio, 3.5; 95% confidence interval, 1.01-11.51; P = .04) were independent predictors of BC occurrence. The actuarial rate of persistent BC was 85% at 18 months. The WIQ scores were lower for patients with persistent BC (median score, 35.04; interquartile range, 16.36; P = .001) compared with patients with regressive BC (median score, 76.5; interquartile range, 36.66; P = .02) or those who never experienced BC after the IOHA procedure (median score, 65.34; interquartile range, 10.94; P < .0003). CONCLUSIONS Pelvic ischemia associated with IOHA may be severe and lead to fatality after EVAR. Our data show that BC may lead to severe quality of life impairment when it does not regress during follow-up.

Simultaneous Reconstruction of Infrarenal Abdominal Aorta and Renal Arteries

From 1980 to 1990, 48 (4.7%) of 1,002 patients underwent elective aortic reconstruction and simultaneous renal artery reconstruction. Forty-five men and three women (mean age: 66.5 years) had 59 renal artery lesions (51 stenoses, six occlusions, one dysplasia, and one aneurysm) associated with 20 infrarenal aortic aneurysms and 28 aortoiliac occlusive lesions. One nephrectomy and 58 renal artery reconstructions were performed (35 prosthetic bypasses, 11 vein bypasses, six direct reimplantations, five transaortic endarterectomies, and one resection of an intrahilar aneurysm followed by autotransplantation). Operation was always indicated for the aortic lesions. Indication for renal artery repair was hypertension in 33 cases (17 associated with renal insufficiency) and one with isolated renal insufficiency. In the remaining 14 cases, surgery was deemed preventive. One patient died (2%). There were 12 nonfatal complications two of which were kidney failures requiring chronic extrarenal epuration. Routine follow-up arteriograms showed four postoperative renal artery occlusions. Mean follow-up was 35.8 months. Four patients were lost to follow-up; 10 died secondarily. Five year survival was 72.1±19.1%. Secondary patency of renal artery reconstruction was 89.5±9.4% at five years. Late results were favorable in 45% of patients with hypertension and in 39% of patients with renal insufficiency. Mortality in simultaneous aortic and renal artery reconstruction is not superior to that of isolated infrarenal aortic surgery.

Multiple aneurysms in a seven-year-old child.

Arterial aneurysms, rarely encountered in childhood, pose difficult etiologic and therapeutic problems. We report the case of a seven-year-old Algerian girl with aortoiliac, visceral, and limb aneurysms revealed by a tumefaction in the left popliteal fossa. Aortic rupture subsequently occurred. The aneurysms were resected with subsequent prosthetic or vein graft replacement. Three years later, clinical and functional results of the grafts were satisfactory. Possible etiologies include inflammatory arteritis, dysplasia, or idiopathic primary aneurysms.

Use of descending thoracic aorta for lower limb revascularisation

From November 1984 to May 1991, descending thoracic aorta to femoral artery bypass was used to revascularise 51 lower limbs in 27 patients. There were 25 men and 2 women with a mean age of 60.2 years. There were four primary indications because of inability to use the abdominal aorta, and 23 secondary indications for late failure of a previous lower limb revascularisation: two aorto-prosthetic false aneurysms, nine infected aorto-bifemoral bypasses and 12 occluded grafts. Three deaths and one paraplegia occurred during the postoperative period, and three prosthetic occlusions and one popliteal embolism were successfully treated. During follow up (6-72 months) five deaths and three graft occlusions were observed; at 5 years, the cumulative life expectancy was 61.8 +/- 26.8%, and the cumulative secondary graft patency was 72.6 +/- 24.7%. One prosthetic infection and one ureteric fistula occurred and both were successfully treated. Thoracic aorta to femoral artery bypass is a simple extra-anatomic technique which can be used in cases of failure of a previous aorta to lower limb reconstruction. The haemodynamic results are good, and late results are better than axillo-femoral or bifemoral bypass.

Surveillance des endoprothèses aortiques abdominales : intérêt de l’échographie-doppler standard et avec contraste

OBJECTIVE Long-term surveillance is needed after endovascular aneurysm repair to monitor the aneurysm and search for persistent endoleaks. Our aim was to compare follow-up with duplex ultrasound, with and without a new contrast agent to track endoleaks, versus computed tomography angiography taken as the gold standard. MATERIAL AND METHOD Patients treated with endograft were included prospectively from December 2005 to July 2006. Aortic duplex ultrasound and computed tomography were used to measure maximal aneurysm diameter and detect endoleaks. Patients with a high risk of endoleaks had a contrast-enhanced ultrasound with Sonovue (Bracco, Milan, Italy). We compared echographic and tomographic diameter and studied the sensitivity of ultrasound endoleak diagnosis. RESULTS Sixty-seven patients were included. There was a good correlation between maximum anteroposterior diameters (CCI=0.98) measured by ultrasound and tomography, as well as mean maximum cross section diameters (CCI=0.96). Compared to tomography, the sensitivity of ultrasound endoleaks diagnosis was 44% (kappa=0.58). Contrast injection improved this sensitivity significantly (p<0.001) (sensitivity=88%; kappa=0.72). CONCLUSION These findings confirmed the performance of our ultrasound method for endograft surveillance. Contrast-enhanced ultrasound significantly improves the sensitivity of detection of endoleaks. We suggest alternating ultrasound and tomographic exams. A unique report chart for use nationwide would be useful for standardizing follow-up.

Long-Term Results of Stenting of the Aortic Bifurcation

BACKGROUND To evaluate the long-term results in a multicentric continuous series of narrowing lesions of the aortic bifurcation treated with a kissing stent. METHODS From January, 1st 1999 to the December, 31st 2001, all of the patients (n = 80) presenting with stenosis of the aortic bifurcation (n = 15) and/or the 2 common iliac arteries (n = 65), treated with a kissing stent, in 8 teaching hospitals were collected retrospectively. The risk factors were smoking (91%), dyslipidemia (60%), arterial hypertension (42%) and diabetes (27%). In 84% of cases, the indication for treatment was claudication. The lesions were stenotic < 70% (n = 76) and/or thrombotic (n = 18). The associated lesions were external iliac stenoses (n = 21), common femoral stenoses (n = 19), femoro-popliteal stenoses (n = 42), arteriopathy in the leg (n = 35). Follow-up was clinical examination and Doppler US scan. RESULTS The success rate of the technique was 89%. There were 4 cases (5.3%) of residual stenosis and 4 cases (5.3%) of dissection. The length of the lesions treated in the aorta and the iliac arteries was respectively 17.1 ± 7 and 17.3 ± 9 mm. The stents were all placed as kissing stents, and had a mean diameter and a mean length of 13.75 mm and 56 mm in the aorta and 9 mm and 48 mm in the iliac arteries, respectively. At 5 years, 19 patients had required repeat angioplasty in the treated area, and 13 had undergone open surgery. Primary and assisted primary patency at 5 years were 64.5% and 81.8%, respectively. CONCLUSION Long-term follow-up of endovascular treatment with kissing stents for stenosis of the aortic bifurcation shows that this technique gives good results, though it does not justify doing away with classical revascularisation surgery, in a population with major cardiovascular risk factors.

Subscapular artery Y-shaped flow-through muscle flap: A novel one-stage limb salvage procedure

OBJECTIVES Major tissue loss caused by the critical limb ischemia requires improvement of distal perfusion and cover of large tissue defects. We propose a new method, the y-shaped subscapular artery flow-through (Y-SCAFT) muscle flap using the subscapular artery that yields an arterial graft and a free muscle flap sustained by a collateral branch of this artery. This prospective study evaluated the feasibility of this technique and analyzed wound healing, graft patency, and limb salvage. METHODS Between 2002 and 2007, 20 patients, mean age 64 years (range, 55-79 years), were treated with this technique. All presented with critical ischemia and major tissue loss, with exposure of the tendons, bones, or joint, and were candidates for major amputation. Revascularization and cover of tissue loss with the same Y-SCAFT anatomic unit was used for all patients. The distal anastomosis was performed between the distal branch of the Y-SCAFT and the pedal artery in 9, posterior tibial artery in 4, peroneal artery in 1, lateral tarsal artery in 3, and the plantar artery in 3. In four patients, the distal part of the arterial graft, including the anastomosis, was covered with the muscle flap because the tissue loss was nearby. The proximal anastomosis was performed between a leg artery and the arterial graft in 10 patients. A venous graft was necessary in 10 patients to extend the bypass proximally. RESULTS One patient died during the postoperative period. Duplex control evidenced patency all the Y-SCAFT muscle flaps. Healing was achieved in all patients. Mean follow-up was 31 months (range, 6-58 months). No patients died during follow-up. One patient presented occlusion of the Y-SCAFT muscle flap and underwent amputated. One patient had major amputation despite a patent graft. At 2 years, leg salvage was 85%, patency was 94%, and survival was 94%. At the end of the follow-up, 17 patients (1 death, 2 amputations) had a patent graft, a viable muscle flap, wound healing, and a functional leg. CONCLUSION We showed the clinical feasibility of the technique of Y-SCAFT muscle flap, which allows for revascularization and cover of major tissue loss with one anatomic unit. This method is particularly useful in selected cases with poor run-off and large ischemic lesions.

Endovascular Repair of Abdominal Aortic Aneurysms with a Unibody Stent-Graft: 3-Year Results of the French Powerlink Multicenter Trial

Purpose: To report the results of a prospective multicenter study on endovascular repair of abdominal aortic aneurysms (AAA) using the bifurcated Powerlink stent-graft. Methods: Between June 2000 and July 2001, endovascular AAA repair using the bifurcated Powerlink stent-graft was performed at 14 centers on 64 patients (61 men; mean age 70 years, range 56–90) fit for open repair. All procedures were attended by a proctor. Data were collected prospectively, and surveillance computed tomograms were reviewed by an independent center. Results: Technical success was achieved in all cases. There was no postoperative death. During a minimum 3-year follow-up (mean 40.6 months, range 1–51), there were 3 (4.7%) stent-graft migrations associated with type I endoleaks. Two (3.1%) of these patients were converted to open repair, and 1 had a proximal extension implanted. No aneurysm rupture occurred, and no stent-graft degradation was observed. Six (9.4%) patients had secondary endoleak (3 type I and 3 type II). The limb occlusion rate was 3.1%. Six (9.4%) patients had secondary procedures. At 3 years, 58 (91.0%) patients were available for follow-up (4 deaths, the 2 conversions). There was a significant decrease between preoperative and 3-year mean AAA diameter (54.6±7 versus 47.6±10 mm, respectively; p < 0.001). Aneurysm sac shrinkage was observed in 32 (55.2%) patients. Twenty-five (43.1%) patients had a stable aneurysm sac diameter. Conclusions: Endovascular repair using the bifurcated Powerlink stent-graft is safe and effective. Unibody design seems to confer advantages in terms of durability. These results need to be confirmed by longer follow-up and larger series.

In Vitro Antistaphylococcal Activity of Collagen-Sealed Dacron Vascular Pros theses Bonded With Rifampin, Vancomycin, or Amikacin

The goals of this study were to evaluate the in vitro antistaphylococcal activity of vascular Dacron prostheses to which a type I collagen and an antibiotic had been bonded. Collagen was fixed to the prosthesis either by an original grafting procedure or by impregnation. The antibiotics used included rifampin, vancomycin, and amikacin. They were bonded to the prosthesis either at the same time as the collagen or by soaking the prosthesis in an antibiotic solution at the beginning of the experiment. Each prosthesis was sliced into 6 mm diameter circles and preserved in a solution of saline and albumin, which was changed every day. Three disks were retrieved from each prosthesis at the beginning of the experiment and then every 24 hours; these were placed in gelose smeared withStaphylococcus aureus. The diameter of the inhibition area of each disk was measured at 24 hours. The initial inhibition area (So), the time at which the inhibition area was equal to 50% of So, and the time at which the activity was nil were used to characterize the activity of the prostheses and to calculate a beta coefficient of decreasing activity. The prostheses bonded with vancomycin or amikacin did not show adequate activity. Those bonded with rifampin were effective for at least 4 days. When rifampin was grafted to the prosthesis, the So was 278.6 mm2, 50% of So was reached within 10.4 days, the duration of effective activity was 25.7 days, and the beta coefficient was 0.067. The two prostheses soaked in rifampin had a significantly more rapid decrease (beta=0.19 and 0.56) and a shorter duration of effective activity (12.4 and 4.5 days). Both collagen-coated prostheses, whether impregnated or soaked with rifampin, have a sufficient duration of activity to be tested in an animal model.