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Jean-Pierre Becquemin

Publications and source records attributed to Jean-Pierre Becquemin.

14 recordsLinked to original sources
PubMed2005

Midterm survival after endovascular versus open repair of infrarenal aortic aneurysms.

PURPOSE: To report the midterm survival after endovascular repair (ER) of infrarenal aortic aneurysms and to compare the outcomes to contemporaneous patients treated with open repair (OR). METHODS: Between January 1995 and December 2001, 498 patients were treated for abdominal aortic aneurysm: 289 (52%) underwent OR and 209 (48%) underwent ER at a single center. Preoperative risk factors were graded according to the SVS/AAVS risk stratification. A computerized database was used to record demographic, clinical, and follow-up data. RESULTS: Significant benefits (p<0.0001) were observed in the ER group in terms of mean procedural time (163+/-66 versus 132+/-61 minutes), mean blood loss (1268+/-923 versus 122.5+/-284 mL), and mean hospital length of stay (16.24+/-13.3 versus 9.3+/-11.6 days). The perioperative mortality for OR and ER patients were, respectively, 5.1% and 1.5% (p=0.04). The mean follow-up was 40 months in the OR group (range 0-85) and 19 months in the ER group (range 2-80). Contact was lost with 31 (6%) patients during the study. No overall survival advantage was observed for OR over ER, and comparison of OR and ER according the risk classifications did not yield any significant differences. No patients died of aneurysm rupture, but 7 ER patients had to be converted to open surgery. The cumulative freedoms from reinterventions at 4 years for the OR and ER groups, respectively, were 87% and 63% (p=0.001). Patients treated by OR had better clinical success (p=0.001). Patients in the ER group without iliac artery aneurysm showed a significant improvement (p=0.035) over patients with aneurysmal iliac arteries. CONCLUSIONS: Over the 7 years of this study, ER realized its goal: prevention of aneurysm rupture. Despite a greater number of reinterventions for ER patients, no overall survival difference was observed.

Adult↗
PubMed2004

Thoracic outlet syndrome surgery: long-term functional results.

The treatment of thoracic outlet syndrome (TOS) is controversial and long-term results are poorly documented. This retrospective study was carried out to assess clinical outcome 2 years after TOS surgery and to determine predictive factors of outcome. Between 1979 and 1999, 155 patients underwent TOS surgery. Of these patients, 140 (90.3%) had a minimum follow-up of 2 years. Thirty-six (25.7%) patients underwent bilateral procedures. A total of 176 procedures were reviewed and served as a basis for study. Presenting symptoms were neurologic in 15 cases (8.5%), arm or hand ischemia occurred in 38 cases (21.6%), and venous compression or thrombosis in 27 cases (15.4%). In 96 cases (54.5%), symptoms were mixed. A transaxillary approach (107 cases) was chosen to address venous symptoms and minor arterial dysfunction. A supraclavicular approach (69 cases) was used when there were large abnormal bony structures, neurologic symptoms, and/or severe limb ischemia. The first rib was resected either extensively from its neck to the sternal attachment (54 cases) or partially, including the mid-rib and neck or the mid-rib and sternal attachment (121 cases), depending on symptoms, approach, and surgeon's choice. Whenever present, cervical ribs, anterior scalenus muscle, and various fibrous or muscular compressive structures were also removed. The 2-year functional outcome according to Derkash's classification was assessed by means of a phone survey. Pre-, per-, and immediate postoperative data were recorded and compared to functional outcomes. Mean follow-up was 7.5 A+/- 3.4 years (2a "19 years). Functional results were excellent, good, fair, and poor in 87 (49.4%), 61 (34.6%), 14 (8%),and 14 (8%) procedures respectively. Predictive factors of negative outcomes were acute ischemia ( p < 0.01), sensory or motor deficit ( p < 0.01), and poorly systematized neurological symptoms as presenting symptoms ( p < 0.05), and extended resection of the first rib ( p < 0.01) and severe postoperative complications ( p < 0.01). This series showed that the 2-year results of TOS surgery were satisfactory in the majority of cases. Patients suffering from poorly systematized neurological symptoms in the arm had poor results. This subset of patients should be denied surgery or at least informed that postoperative results might be disappointing. Partial first-rib resection and a careful technique avoiding postoperative complications were also factors in long-term success.

Adult↗
PubMed2004

Outcomes of secondary interventions after abdominal aortic aneurysm endovascular repair.

PURPOSE: We assessed the distribution of secondary interventions after aortic stent grafting (EVAR) performed to treat infrarenal abdominal aortic aneurysm (AAA), and evaluated clinical success and survival in patients who underwent a secondary procedure (group 2) compared with patients who did not undergo a secondary procedure (group 1). METHODS: Two hundred fifty patients (mean age, 71.3 years) with asymptomatic AAAs (mean aneurysm diameter, 54.5 mm) underwent treatment with commercially available stent grafts. Mean follow-up was 28 months (median, 25 months). Secondary procedures were defined as any additional procedures performed after initial graft placement to treat endoleak, migration, kinking, stenosis, or occlusion. Overall clinical success was defined according to reporting standards of the Society for Vascular Surgery/American Association for Vascular Surgery. RESULTS: Sixty-eight patients (27%) required 112 secondary procedures, with a mean time from initial graft placement of 18.2 months. Patients who received grafts since removed from the market required more secondary procedures (59%, procedure:patient ratio) compared with patients who received devices still on the market (21%; P =.001). Thirty-six patients (53%) required a single secondary procedure, 24 patients (35%) required two procedures, 5 patients (10%) required three procedures, 2 patients (3%) required four procedures, and 1 patient required five secondary procedures. Ninety-eight procedures (87%) were performed with endovascular methods, including placement of 42 additional covered stent grafts (36 iliac, 6 aortic), with a success rate of 85%; 35 embolization procedures (21 lumbar, 9 internal iliac artery, 5 mesenteric), with only 23 (65%) successful; 14 angioplasty procedures, with 85% successful; 4 thrombolysis procedures, 2 of them successful (50%); and 3 successfully placed new endografts within a previous endovascular graft. Surgical secondary operations included nine femorofemoral bypass procedures and three femoral thromboendarterectomies, all of which remain patent; one cerclage of an external iliac limb; and one laparoscopic repair of a type II endoleak, which was successful. Overall clinical success rate for EVAR was 84% (211 of 250) in this series. Clinical success rate in groups 1 and 2 was 91% (166 of 182) versus 66% (45 of 68; P =.001) if all endoleaks on the most recent computed tomography scans are taken into account, and 94% (171 of 182) versus 76% (52 of 68; P =.001) if type II endoleak without aneurysm growth is not considered failure. The survival rate and rupture-free survival in groups 1 and 2 were, respectively, 97.7% +/- 1.0% and 98.5% +/- 1.4% at 1 month, 95.9% +/- 1.5% and 96.9% +/- 2.1% at 6 months, 94.4% +/- 2.0% and 93.2% +/- 3.4% at 1 year, and 80.8% +/- 5.2% and 88.5% +/- 5.0% at 3 years (P =.273, log-rank test). CONCLUSION: With close follow-up and a significant number of secondary operations, this 8-year experience has not included any aneurysm ruptures to date. Secondary operations did not lead to increased mortality, but were associated with more surgical conversions and with a higher clinical failure rate.

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PubMed2004

Vascular smooth muscle cell endovascular therapy stabilizes already developed aneurysms in a model of aortic injury elicited by inflammation and proteolysis.

OBJECTIVE: To investigate the efficiency of endovascular smooth muscle cell (VSMC) seeding in promoting healing and stability in already-developed aneurysms obtained by matrix metalloproteases (MMPs)-driven injury. SUMMARY BACKGROUND DATA: VSMCs are instrumental in arterial healing after injury and are in decreased number in arterial aneurysms. This cellular deficiency may account for poor healing capabilities and ongoing expansion of aneurysms. METHODS: Aneurysmal aortic xenografts in rats displaying extracellular matrix injury by inflammation and proteolysis were seeded endoluminally with syngeneic VSMCs, with controls receiving culture medium only. Diameter, structure, and the destruction/reconstruction balance were assessed. RESULTS: Eight weeks after endovascular infusion, aneurysmal diameter had increased further, from 3.0 +/- 0.3 mm to 10.9 +/- 6.5 mm (P = 0.009), and medial elastin content had decreased from 36.5 +/- 8.5 to 5.2 +/- 5.5 surface-percent (S%; P = 0.009) in controls, whereas these parameters remained stable in the seeded group (3.0 +/- 0.3 to 2.7 +/- 0.2 mm, P = 0.08; 36.5 +/- 8.4 to 31.6 +/- 9.7 S%, P = 0.22). VSMC seeding was followed by a decrease in mononuclear infiltration. MMP-1, -3, -7, -9, and -12 mRNA contents were sharply decreased in the diseased wall in response to seeding. Tissue inhibitor of metalloproteinase-1, -2, and -3 mRNAs in the intima were increased in a 2 to 10 magnitude in comparison with controls. Gelatin zymography showed the disappearance of MMP-9 activity and reverse zymography a strong increase in tissue inhibitor of metalloproteinase-3 activity in the seeded group. VSMC-seeded aneurysms were rich in collagen and lined with an endothelium instead of a thrombus in controls. CONCLUSIONS: VSMCs endovascular seeding restores the healing capabilities of proteolytically injured extracellular matrix in aneurysmal aortas, and stops expansion.

Animals↗
PubMed2003

Iliac artery rupture during balloon dilatation: what treatment?

Intraoperative and postoperative arterial ruptures associated with 657 iliac artery balloon dilatation procedures in our department from 1981 to 2000 were prospectively collected and retrospectively analyzed. Our results showed that failure to exercise basic safety principles and the presence of heavily calcified plaque are the major predictors of iliac artery rupture during balloon dilatation. If rupture is contained, surveillance alone is unreliable. Optimal treatment requires temporary hemostasis by balloon tamponade followed by placement of a covered stent to occlude the opening.

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PubMed2003

Paracrine secretion of transforming growth factor-beta1 in aneurysm healing and stabilization with endovascular smooth muscle cell therapy.

BACKGROUND: Identification of molecular factors involved in artery wall stabilization after extracellular matrix injury elicited by inflammation and proteolysis has a major role in the development of new therapies for atherosclerosis. A study from our group demonstrated that endovascular seeding of vascular smooth muscle cells (VSMCs) promotes healing and stabilizes experimental aneurysms by downregulating matrix metalloproteinase and upregulating tissue inhibitor of metalloproteinase and collagen gene expression. We analyzed expression of transforming growth factor-beta (TGF-beta) and its receptors in experimental aneurysms treated with endovascular VSMC therapy. METHODS AND RESULTS: Aneurysms were generated in Fischer 344 rats by 14-day orthotopic implantation of a segment of guinea pig abdominal aorta (xenograft). During an endovascular repeat operation, syngeneic VSMCs were seeded in the aneurysm, always resulting in aneurysm diameter stabilization after 8 weeks, whereas diameter of control aneurysms infused with culture medium further increased. Seven days after repeat operation the intima or thrombus was separated from the aneurysmal wall in the two groups. Reverse transcriptase polymerase chain reaction with the domestic gene 18s as a standard demonstrated that aneurysm stabilization was associated with a statistically significant increase in TGF-beta(1), but not TGF-beta(2) or TGF-beta(3), messenger RNA levels in the intima. Enzyme-linked immunosorbent assay demonstrated increased TGF-beta(1) protein in the aneurysmal wall. mRNA levels of the two serine and threonine kinase TGF-beta receptors remained unchanged. CONCLUSIONS: Healing and stabilization of aneurysms with endovascular cell therapy is associated with a specific pattern of gene expression, resulting in paracrine secretion of TGF-beta(1). Our study provides insight into the molecular mechanisms of arterial aneurysm healing and stabilization.

Animals↗
PubMed2003

Systematic versus selective stent placement after superficial femoral artery balloon angioplasty: a multicenter prospective randomized study.

PURPOSE: Outcome with selective or systematic stenting with the Palmaz vascular stent was compared in patients with limb-threatening ischemia or persistent disabling claudication despite medical therapy, with less than 7 cm stenosis or occlusion of the superficial femoral artery. METHODS: This was a multicenter prospective randomized trial with centralized allocation of treatment and independent review of vascular events. The primary end point was presence of more than 50% stenosis at 1-year angiographic follow-up. Secondary end points were survival; occurrence of vascular events in the treated leg; and number of failed procedures, defined as more than 50% stenosis or death at 1 year. RESULTS: Two hundred twenty-seven patients were enrolled in the study, 112 in the selective stent group, and 115 in the systematic stent group. Seventeen patients (15%) in the selective stent group received a stent after suboptimal results of percutaneous transluminal angioplasty. Angiograms for 140 patients were available at 1-year follow-up and demonstrated no statistical difference between the two groups; more than 50% stenosis of the dilated site was noted in 21 of 65 patients (32,3%) in the selective stent group and 26 of 75 patients (34.7%) in the systematic stent group (P =.85, Fisher exact test). Survival in the percutaneous transluminal angioplasty and stent groups was, respectively, 92% and 96% at 1 year, 89% and 93% at 2 years, and 82% and 80% at 4 years (P =.40, log-rank test). Survival free of new vascular events in the treated limb was 77% and 65% at 1 year, 70% and 53% at 2 years, and 57% and 44% at 4 years (P =.017, log-rank test). Number of failed procedures at 1 year was 29 of 86 (33%) and 30 of 89 (34%) (P = 0.9). CONCLUSION: Systematic stenting of short stenosis or occlusion of the superficial femoral artery is not justified. Palmaz vascular stent placement should be reserved for use in patients with suboptimal results of balloon angioplasty.

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PubMed2003

Cardiac autonomic control during balloon carotid angioplasty and stenting.

Hemodynamic alterations during balloon carotid angioplasty (BCA) and stenting have been ascribed to the consequences of direct carotid baroreceptor stimulation during balloon inflation. BCA with stenting in patients with carotid atheromatous stenoses offers a unique opportunity for elucidating the cardiovascular autonomic response to direct transient intravascular stimulation of the baroreceptors. We analysed the consequences of BCA on the autonomic control of heart rate and on breathing components in nine patients with atheromatous stenoses involving the bifurcation and the internal carotid. A time-frequency domain method, the smoothed pseudo-Wigner-Ville transform (SPWVT), was used to evaluate the spectral parameters (i.e., the instantaneous amplitude and centre frequency (ICF) of the cardiovascular and respiratory oscillations). Those parameters and their dynamics (8 and 24 h later) were evaluated during and after the procedure. BCA stimulates baroreceptors in all patients, which markedly reduces heart rate and blood pressure. Vagal baroreflex activation altered the respiratory sinus arrhythmia in terms of amplitude and frequency (ICF HF RR shifted from 0.27 +/- 0.03 to 0.23 +/- 0.04 Hz pre-BCA vs. BCA, respectively; p < 0.01). Both the high- and low-frequency amplitudes of heart rate oscillations were altered during carotid baroreceptor stimulation, strongly supporting a contribution of the baroreflex to the generation of both oscillations of heart rate. Carotid baroreceptors stimulation increased the inspiratory time (Ti) (1.5 +/- 0.5 to 2.3 +/- 0.6 s pre-BCA vs. BCA, respectively; p < 0.01). In awake patients, BCA with stenting of atheromatous stenosis involving the bifurcation and internal carotid causes marked changes in the cardiac autonomic and respiratory control systems.

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PubMed2003

Carotid stenting versus carotid surgery: a prospective cohort study.

PURPOSE: To compare the results of carotid stenting and carotid surgery in a consecutive group of 455 patients (482 lesions). METHODS: Between January 1995 and July 2002, 107 patients (114 lesions) were treated with carotid stenting and 348 patients (368 lesions) with carotid surgery. A cerebral protection device was routinely used in the last 46 stent cases. All patients were followed with duplex examination at 1 and 6 months postoperatively and yearly thereafter. RESULTS: The stent and surgery groups were similar in terms of mean age (70.5 and 71.1 years, respectively), sex distribution (men 72% versus 75%), and symptoms (transient ischemic attack [TIA] or minor stroke 32.7% versus 42.2%). Median follow-up was 15 months in stent patients and 14 months in the surgical group. At 1 month postoperatively, there were 7 minor strokes (5 temporary lasting <21 days and 2 persistent) and 1 major stroke in the stent group versus 1 persistent minor stroke in the surgical patients. The overall neurological event rate (including TIA) was 10.5% versus 1.9% (p=0.0002) in the surgical patients; cardiac morbidity was 3.5% versus 1.6% (p=NS), and the death rate was 0% versus 0.8% (p=NS). The combined permanent stroke/death rate was 2.6% in stent patients and 1.1% in surgery patients (p=NS). During follow-up, the cumulative all stroke rate was 8.8% versus 1.9% (p=0.001), but the 3-year cumulative survival rate free from ipsilateral major neurological events was 95.2% in stent patients and 96.9% in the surgery cohort (p=NS). There was a 7.5% rate of restenosis in stented arteries versus 1.4% in surgery patients (p=0.001). CONCLUSIONS: This series showed encouraging and comparable major stroke and deaths rate of carotid stenting and carotid surgery. However, there was more restenosis in the stented group on midterm follow-up.

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PubMed2003

Frequency, predictive factors, and consequences of stent-graft kink following endovascular AAA repair.

PURPOSE: To determine from the EUROSTAR registry the incidence of stent-graft kink, predictive factors for kinking, and the consequences of this complication on graft patency and aneurysm exclusion. METHODS: From January 1994 to June 2002, 4613 patients who underwent endovascular aneurysm repair were registered in the EUROSTAR registry. Presence of kink was determined according to the information available on the follow-up Case Record Form. The population was divided into those with and without stent-graft kink. Patient characteristics, morphological aneurysm features, team experience, type of device, period of implantation, and outcome were compared between the groups by univariate analysis. Significant factors were subsequently submitted to a multivariate Cox proportional hazard analysis. RESULTS: One hundred seventy (3.7%) patients were reported as having a kink of the stent-graft during a mean follow-up of 21 months (range 1-72). Gender, neck angulation, team experience, period of implantation, ASA classification, and device type were independent predictors of kink. The presence of a kink was significantly associated with type I endoleaks (proximal and distal), type III endoleaks (midgraft), graft stenosis, graft limb thrombosis, graft migration, and conversion to open repair. No relationship was found between a decrease in the aneurysm diameter and the occurrence of stent-graft kink. CONCLUSIONS: Kinks of stent-grafts were infrequent events in the intermediate term. Patients most at risk were women with angulated aortic necks treated by a minimally experienced team. Kinks are potentially damaging events because they may lead to delayed device-related endoleaks, graft stenosis, thrombosis, and conversion to open repair. They appear more closely associated to graft migration than to aneurysm diameter reduction.

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PubMed2002

Percutaneous coil embolization of postcatheterization arterial femoral pseudoaneurysms.

STUDY DESIGN: This study was a prospective monocentric study to assess the safety and effectiveness of percutaneous embolization with coils of postcatheterization femoral pseudoaneurysm (PCFP). PATIENTS AND METHODS: Seventeen PCFPs of 32-mm mean diameter in 16 patients were embolized while anticoagulant or antiplatelet therapy was maintained. Ultrasound scan-guided compression repair failed at least one time in 13 cases and was contraindicated in the four remaining cases. With ultrasound-Doppler scan guidance, the PCFPs were percutaneously punctured with a 16-gauge intravenous catheter. An angiogram was performed through the catheter to ensure its location within the sac. Stainless steel spring coils with synthetic fibers were introduced within the PCFP with fluoroscopic control. Successful thrombosis was checked with ultrasound-Doppler scan and was repeated at days 1, 30, and 180 when possible. RESULTS: All PCFPs of 32-mm mean diameter were successfully treated with two to nine coils. After embolization, gentle additional compression was necessary for complete occlusion, with a mean duration of 6.3 minutes (range, 0 to 15 minutes), except in one case with treatment with abciximab in which it was 45 minutes. All procedures were uneventful and painless. The mean follow-up period was 9.5 months (range, 1 to 21 months). Two recurrences (11.7%) were observed, and one was successfully treated with a second embolization. CONCLUSION: Percutaneous embolization with coils appears to be a safe and effective method for treatment of PCFP. It may be performed in patients undergoing anticoagulant or antiplatelet therapy and must be attempted when ultrasound scan-guided compression repair has failed or is contraindicated.

Adult↗
PubMed2002

Paracrine effect of vascular smooth muscle cells in the prevention of aortic aneurysm formation.

OBJECTIVE: Inflammation and elastinolysis are observed in the media of abdominal aortic aneurysms (AAAs) where vascular smooth muscle cell (VSMC) density is decreased. In contrast, elastin and VSMCs are preserved in the noninflammatory media of stenotic atherosclerotic lesions. We have tested the hypothesis that VSMCs exert a protective effect against inflammation and proteolysis in a model of AAA in rats, in which medial elastin degradation is driven by inflammation and matrix metalloproteinases. METHOD: Decellularized guinea pig aortas (xenografts) were implanted orthotopically into Fischer-344 rats and seeded with a suspension of rat VSMCs syngeneic to the rat recipient, or were infused with culture medium as a control. Diameter and elastin in the media were quantified 8 weeks after implantation. Inflammation, matrix metalloproteinase (MMP) and tissue inhibitor of matrix metalloproteinase (TIMP) expression were analyzed 1 and 2 weeks after implantation. RESULTS: VSMC addition prevented AAA formation (mean +/- standard deviation diameter increase: 198.2% +/- 106.6% vs 35.3% +/- 17.8%, P =.009), elastin degradation, and decreased infiltration by monocyte-macrophages. Reverse-transcriptase polymerase chain reaction, zymography and reverse zymography for MMP-2, MMP-9, TIMP-1, TIMP-2, and TIMP-3 demonstrated a shift of the proteolytic-antiproteolytic balance upon addition of VSMCs. Transcriptional changes were observed in the adventitia, although seeded VSMCs remained located in the intima. CONCLUSIONS: VSMCs exert a paracrine effect on the adventitia that participate in artery wall homeostasis against inflammation and proteolysis. Failure of this protective mechanism results in AAA formation. The understanding of the molecular mechanisms underlying VSMC protective effect may represent a new approach in the treatment of aneurysm and plaque rupture.

Animals↗
PubMed2002

Endograft fabric disintegration simulating a type II endoleak.

PURPOSE: To report a case of endograft disintegration misinterpreted as a type II endoleak. CASE REPORT: An 86-year-old man underwent successful Vanguard stent-graft implantation for a 49-mm abdominal aortic aneurysm. At 1 month, a distal type I endoleak was repaired, but another endoleak thought to arise from the lumbar or inferior mesenteric arteries remained. Multiple interventions to embolize the feeding arteries were unsuccessful, and the endoleak persisted. At 1 year, the leak was still present, and the aneurysm had increased to 69 mm. After failing to demonstrate the source of the leak radiographically, surgery was performed. At operation, the endoleak was traced to small holes in the graft fabric. The endograft was removed without difficulty, and the flow was re-established with an aortobi-iliac woven graft. CONCLUSIONS: Chronically implanted stent-grafts can show signs of failure that are confusing or misleading. Correct diagnosis of endoleaks may be difficult, but every effort must be made to identify their source. It is vital that no enlarging aneurysm be left untreated.

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