Biomedical subjects
Publications and source records attributed to H Lacroix.
Thirty-three symptomatic scaphoid non-unions were treated by a simple, minimally invasive procedure using a percutaneous autologous corticocancellous bone graft. After an average follow-up of 3.5 years, union was observed in 29 cases. These patients had no, or mild, pain at work and an almost normal range of motion and grip strength. No progression to osteoarthritis was observed.
The case report of a 32-year-old man with a Brugada syndrome is presented. He was asymptomatic and without familial history of sudden death or syncope. Diagnosis criteria for Brugada syndrome were 1--a pattern of right bundle branch block and ST-segment elevation in leads V1 and V2 on the ECG, 2--no cardiac structural anomalies. Symptomatic patients with this electrical anomaly are at high risk of sudden death and need an automatic implantable defibrillator. The outcome and the treatment of asymptomatic patients are a matter of debate and are discussed in this report.
Rupture of a renal artery aneurysm during pregnancy is a rare event, with a high mortality rate for both mother and fetus. Until now, 25 cases have been reported in the English medical literature. Renal salvage with in situ repair of the renal artery has been documented in only four cases, and successful ex situ repair and autotransplantation in only one case. We report the case of a mother and fetus who both survived acute rupture of a renal artery aneurysm after treatment with ex situ repair and autotransplantation.
Vitamin D insufficiency is still a concern in countries where there is no routine food supplementation, such as France. A low vitamin D status is clearly associated with an increased risk of fracture in the elderly, but the long-term consequences of latent vitamin D insufficiency in young people and adults are not known. We fed 26 growing pigs a high calcium diet (1.1%) with a 1000 IU cholecalciferol/kg diet (controls), or without vitamin D (0D) for 4 months. We then analyzed the overall impact of low vitamin D status on osteotropic hormones (calcitriol and immunoreactive parathyroid hormone), plasma markers of bone remodeling (alkaline phosphatase [ALP] activity, carboxyterminal propeptide of type I procollagen [PICP], osteocalcin, hydroxyproline), whole bone parameters (ash content, bending moment), histomorphometry, and the populations of marrow osteoblastic and osteoclastic precursors by ex vivo cultures. The fall in plasma 25-dihydroxyvitamin [25(OH)D] in the 0D pigs indicated severe depletion of their vitamin D stores. However, they remained normocalcemic, were mildly hyperparathyroid after 2 months of vitamin D deprivation, and showed only a slight decrease in plasma calcitriol. The bone mineral content and bending moment of metatarsals decreased and they had increased osteoblastic (+59%, p < 0.05 0D vs. controls) and osteoclastic (+31%, p < 0.1 0D vs. controls) surfaces. This was not paralleled by increased bone turnover, because plasma hydroxyproline and ALP were unchanged and PICP and osteocalcin were decreased. The adherent fraction of bone marrow cells showed a great increase in the number of total stromal colony-forming units (CFU-F; +93%, p < 0.05 0D vs. controls) and in the percent of ALP(+) CFU-F (+58%, p < 0.01 0D vs. controls) in cultures from 0D pigs. More tartrate-resistant acid phosphatase-positive (TRAP(+)) multinucleated cells were generated in cultures of nonadherent marrow cells from 0D pigs, and the area of resorption was 345% greater than in controls. Thus, vitamin D deprivation caused only moderate hormonal changes in growing pigs fed a high-calcium diet, but affected their bone characteristics and greatly enhanced the pool of osteoblasts and osteoclasts by stimulating the commitment of their precursors in bone marrow.
Wild-type or equipotent variants of recombinant staphylokinase (rSak) were given intra-arterially (as a 2 mg bolus injection followed by an infusion of 1 mg/h or 0.5 mg/h overnight, with concomitant heparin [1000 IU/h]) to 191 patients of less than 80 years (62 +/- 1 years, mean +/- SEM), with a peripheral arterial occlusion (PAO) of less than 120 days (mean 14 +/- 1 days, median 11 days, 5 to 95 percentiles 3 to 30 days). Ninety nine patients presented with acute or subacute ischemia, 57 with severe claudication, 33 with chronic rest pain and 2 with gangrene. Occlusion occurred in 122 native arteries and in 69 grafts. Revascularization was complete in 83 percent (158/191), partial in 13 percent (24/191) and absent in 4 percent (7/191) after administration of 12 +/- 0.5 mg rSak over 14 +/- 0.7 h. Complete revascularization of acute occlusions of popliteal or more distal arteries was less frequent (60 percent, 15/25) than of acute occlusions of more proximal native arteries (95 percent, 37/39, p <0.001) or grafts (89 percent, 50/56, p = 0.005). Additional endovascular procedures were performed in 47 percent and subsequent elective bypass surgery in 23 percent of patients. Major bleeding occurred in 12 percent (23/191), one month mortality was 3.1 percent (6/191) and one year mortality was 6.9 percent (12/174). However, four patients (2.1 percent) had an intracranial bleeding following therapy: a 85 year old woman with severe diabetic arteriopathy, who was included in violation of the protocol, a 79 and a 74-year-old woman and a 74-year-old man, all with severe hypertension and limb threatening ischemia; these four patients died within two months after treatment. Amputations were performed within the first year in 16 of 162 surviving patients (9.8 percent): in 7 percent (7/96) with an occluded native artery and 14 percent (9/66) with an occluded graft (p = 0.19). No significant difference in lysis rate, one month mortality or one year amputation-free survival was observed in occlusions of recent onset (< or =14 days, n = 126) as compared to occlusions of longer duration (>14 days, n = 65). Treatment was interrupted prematurely in 4 patients because of a suspected allergic reaction. Fibrinogen levels remained unaffected during treatment (3.3 +/- 0.1 g/l before vs. 3.3 +/- 0.1 g/l after infusion, n = 167). In conclusion, rSak appears to be a highly effective thrombolytic agent in patients with PAO, resulting in a low one month mortality (3.1 percent) and a high one year amputation free survival (84 percent), with an acceptable incidence of major bleedings, but with occasional fatal intracranial hemorrhages.
BACKGROUND: The aim of this study was to evaluate the ability of dipyridamole thallium scintigraphy and dobutamine stress echocardiography to predict cardiac complications following elective reconstruction of the abdominal aorta in patients with a stable preoperative cardiac condition and to compare this with information obtained from the medical history, ECG and resting echocardiography alone. METHODS: This evaluation was performed from January 1993 until December 1995 as part of a prospective, randomised study in 200 patients, with a mean age of 65 (5% women). Dipyridamole thallium scintigraphy was performed on 195 patients and dobutamine stress echocardiography was added to the protocol in the last 83 patients. Cardiac complications were defined before the start of the study. RESULTS: In the postoperative period 62 cardiac complications occurred (31%). In patients clinically suspected of having coronary artery disease the incidence of complications was 40% (51/126), compared to 15% (11/74) when no coronary pathology was suspected (p<0.001). When reversible defects were present on dipyridamole thallium scintigraphy the incidence of complications was 36% (20/55), compared to 29% (41/140) when no reversible defects had been found (NS). Dobutamine stress echocardiography was impossible or contraindicated in 21 patients. In the remaining patients the incidence of complications was 71% (5/7) when new regional wall motion abnormalities were found, compared to 16% (9/55) when such abnormalities had not been detected (p<0.005). CONCLUSIONS: These data suggest that cardiac complications following reconstruction of the abdominal aorta in patients with a stable cardiac condition are best predicted by dobutamine stress echocardiography. Dipyridamole thallium scintigraphy, however, does not seem to be useful in this respect.
Inflammatory abdominal aortic aneurysms may present a challenge to the surgeon, especially because of associated retroperitoneal fibrosis and possible ureteral complications. We present a case of inflammatory abdominal aortic aneurysm with bilateral ureteral entrapment and complete anuria, successfully treated by endovascular grafting and temporary ureteral stenting.
The aim of this study was to test the hypothesis that a drop in the systolic blood flow velocity in the middle cerebral artery of 70% or more, measured by transcranial Doppler, is a better criteria in the detection of cross-clamp intolerance than electroencephalogram (EEG) and somatosensory evoked potential (SSEP) monitoring. After exclusion of patients with a recent stroke, urgent procedures and combined procedures, a transcranial Doppler with compression test was scheduled in 85 patients. In 13 patients the drop was 70% or more and in these patients a transcranial Doppler was also performed during the reconstruction of the internal carotid artery (the study group) under general anaesthesia. A shunt was used because of EEG and SSEP abnormality in one patient. No changes were observed in the remaining patients and no intraoperative strokes were seen. The transcranial Doppler monitoring was unreliable in three patients. During cross-clamp, the systolic blood flow velocity in the middle cerebral artery dropped less than 70% in four and 70% or more in six patients. It is concluded that using a drop of 70% or more of the systolic blood flow velocity in the middle cerebral artery during internal carotid artery cross-clamp, as an indicator of cross-clamp intolerance, will lead to unnecessary shunting.
OBJECTIVES: to identify risk factors for complications following endovascular repair of abdominal aortic aneurysms (AAAs). MATERIALS AND METHODS: endovascular AAA exclusion was attempted in 64 patients. Patient characteristics, anatomic features of the aneurysm, operative technical aspects, and the experience of the teams were correlated with mortality, occurrence of endoleak, and other complications. Perioperative complications were graded following the recommendations of the Ad Hoc Committee on reporting standards. For the assessment of correlation between risk factors and outcomes a logistic regression analysis was used. RESULTS: complications were observed in 43% of the procedures and were classified as mild (24%), moderate (55%) or severe (21%). American Society of Anaesthesiology (ASA) risk class 3 or 4, and advanced age were independent risk factors for perioperative death and complications. Adjuvant procedures or overstenting of the renal arteries with the uncovered part of the stent were not associated with increased risk of complications. Nevertheless, in four of 24 overstented renal orifices, a renal infarction or ischaemia of the kidney was observed on a postoperative CT scan. Advanced experience was associated with less complications, less endoleaks, and shorter operating time. CONCLUSIONS: high age and medical co-morbidity were associated with increased risk for perioperative complications and death. Additional perioperative procedures are usually well tolerated. With greater experience in endovascular AAA grafting the incidence of complications and endoleaks decreased.
Arterial occlusion after total knee arthroplasty is an uncommon complication. In the literature only a few cases have been reported, and non consensus exists on the optimal management for this condition. The authors report two patients with popliteal artery thrombosis in the early postoperative period. Both patients were treated with percutaneous thrombus aspiration, a technique that has not been reported previously for this indication. In both patients complete restoration of arterial perfusion and limb salvage was achieved, although ischemic necrosis of the anterior compartment muscles of the lower leg could not be prevented.
Although sound evidence is lacking, many surgeons claim that stripping of the long saphenous vein (LSV) is best performed by invagination. The aim of this prospective, randomized study was to test the hypothesis that invaginating stripping of the LSV is associated with less pain, smaller haematomas and less frequent injury to the saphenous nerve. Thirty patients with bilateral varicose veins and incompetent LSV, but normal short saphenous veins and deep venous systems, were treated by high ligation and stripping of the LSV and multiple stab avulsions. At one side the stripping was performed by invagination (group I), while a classic stripping was done on the other side (group C), so that one leg served as the control of the other. The results were analysed on an intention to treat basis. The median surface of the thigh haematoma between post-operative day seven and ten was 115 cm2 in group I and 135 cm2 in group C (NS). The median pain score was 0.25 and 1.75 respectively (NS). The incidence of saphenous nerve injury was 13% in group I and 17% in group C (NS). At one month 23% of patients stated that the leg with the invaginating stripping had been the more painful, while 33% of patients claimed that the side of the classic stripping had been more painful. The results show that the benefit of invaginating stripping is not as obvious as is generally suggested.
This retrospective study was undertaken to investigate the patency and limb salvage rates of 308 PTFE infrainguinal bypasses in 272 patients over a 5-year period. In addition a univariate analysis was performed to identify factors that could predict the outcome of these operations. Long-term survival was 83% and 50% at one and five years respectively. For the whole series the primary cumulative patency at one and five years was 70% and 41% respectively. Graft revision for failed or failing grafts resulted in secondary patency rates of 78% and 43% for the same periods. The limb salvage rates were 93% and 84% at one and five years. Patency rates showed no statistical significant difference for gender, age at operation or the use of a venous cuff at the distal anastomosis. Although there was a tendency towards better results for above the knee operations, this difference failed to achieve statistical significance. Only redo operations were associated with a significant worse outcome.
In recent years laparoscopic techniques have been adapted for application in vascular surgery. Since 1993 several authors have published preliminary results of complete or videoscopic-assisted reconstructions of the abdominal aorta. The aim of this retrospective study was to report our initial results with the retroperitoneal videoscopic-assisted technique of aorto-bifemoral grafting (AFG) in ten patients (age 45-71). In one case, conversion into classic reconstruction was necessary because the aorta was to heavily calcified. The duration of the procedures varied between 230 and 390 minutes. The length of the incision ranged between 6 and 9 cm. The hospital stay varied between 5 and 13 days. One patient developed gout, and a left sided, temporary ureteral stent was necessary in another because of hydronephrosis. It is confirmed that video-assisted AFG is feasible. However, whether this technique is truely less invasive, will have to be demonstrated by randomized, prospective studies, once the equipment and instruments have sufficiently been developed and a technique of choice finalized.
In this clinical case we report the use of the superficial femoral vein as an autologous venous interposition graft for the reconstruction of the iliofemoral vein in a 21-year-old female who presented with an asymptomatic primary aneurysm of the left iliofemoral vein. The choice of surgical technique used is discussed.
The authors present a retrospective study on 30 patients with prosthetic graft infection. Included are 25 patients with aortic graft infection, three with infection of a femorodistal bypass and two with infected axillofemoral grafts. There were 23 isolated primary prosthetic graft infections and seven aorto-enteric fistulas. Treatment consisted of graft excision and replacement with cryopreserved arterial homografts, harvested from brain-death multi-organ donors. The in situ technique was used in 27 cases. Eight patients died postoperatively and two deaths were from allograft related complications. The operative mortality rate was 11% for isolated aortic graft sepsis and the early limb salvage rate was 100%. Persistent or recurrent infection was noted in two cases. The mean follow-up of the series was 24.5 months and occlusive complications occurred in five patients (23%), which resulted in two major amputations. Serial CT scans showed abnormalities in six of the 22 survivors, all of them related to the aortic segment of the allograft. It is concluded that in situ reconstruction with cryopreserved arterial allografts represents an acceptable alternative, especially in the treatment of isolated aortic graft sepsis. Continued follow-up towards late deterioration and/or occlusive complications remains mandatory.
The development of docetaxel, a member of the taxoid family, has been recent and rapid. Phase I studies recommend that a dose of 100 mg/m(2) be administered every three weeks in a 1-h infusion. These studies have also demonstrated that the major dose-limiting toxicity is neutropenia. Major clinical research projects are now being carried out for breast cancer, non-small-cell lung cancer (NSCLC), squamous cell carcinoma of the head and neck (SCCHN) and gastric cancer. In advanced and metastatic NSCLC, Phase II studies have shown a response rate of 30 - 40%, and responses have been obtained in cis-platinum failures. In advanced and metastatic breast cancer, first-line treatment has yielded a response rate of 54 - 68%, and the rate for second-line response is only slightly lower, indicating an absence of cross-resistance. Phase II combination studies with docetaxel are in progress, and preliminary results are promising. The first Phase III study demonstrated preliminary response rates significantly higher than seen with doxorubicin, although survival data have not yet been published. Fewer results are available from SCCHN studies, but response rates have been encouraging (around 40%). Although further long-term data are needed to determine the precise role of docetaxel in combination with other drugs, it is apparent that this promising drug shows one of the best response rates for monotherapy in NSCLC and breast cancer.
BACKGROUND: The thrombolytic potency and antibody induction of selected variants of recombinant staphylokinase (SakSTAR), including SakSTAR(K74) with Lys74, SakSTAR(E75) with Glu75-, SakSTAR(EER) with Glu38, Glu75, and Arg77, and SakSTAR(K74ER) with Lys74, Glu75, and Arg77 replaced by Ala, were studied. METHODS AND RESULTS: In rabbits, SakSTAR(74) and SakSTAR(EER) elicited significantly less circulating neutralizing activity than SakSTAR and SakSTAR(E75) (P = .005 and P = .0002 versus SakSTAR, respectively). In baboons, SakSTAR(K74) induced significantly fewer antibodies than wild-type SakSTAR (P < .05). Intra-arterial administration in patients with peripheral arterial occlusion of SakSTAR(K74) (n = 11) or SakSTAR(K74ER) (n = 6) induced significantly fewer circulating neutralizing antibodies [median values and interquartile ranges, 20 (3.8 to 26) and 2.4 (0.2 to 59) micrograms compound neutralized/mL plasma after 3 to 4 weeks (P = .01 and P = .035 versus SakSTAR, respectively)] than SakSTAR (n = 9) [median value and interquartile range, 93 (24 to 110) micrograms compound neutralized/mL plasma]. Overt neutralizing antibody induction (> 10 micrograms compound neutralized/mL plasma) occurred in all 9 patients given wild-type SakSTAR, in 6 of the 11 SakSTAR(K74ER) patients (P = .038 versus SakSTAR), and in 2 of the 6 SakSTAR(K74ER) patients (P = .011 versus SakSTAR). CONCLUSIONS: SakSTAR(K74), a variant of recombinant staphylokinase with a single substitution of Lys74 with Ala, and SakSTAR(K74), with Lys74, Glu75, and Arg77 substituted with Ala, have intact thrombolytic potencies but induce significantly less antibody formation in patients.
The aim of our study was to evaluate the results of catheter-directed thrombolysis and complementary procedures to treat acute iliofemoral deep vein thrombosis (DVT). A total of 24 consecutive patients with acute iliofemoral DVT underwent intrathrombus drip infusion of alteplase (3 mg/h; mean dosage 86 mg, range 45-174 mg), while intravenous heparin (1000 U/h) was continued. Complementary procedures were hydrodynamic thrombectomy in 3 and primary insertion of a Wallstent in 9 patients. Patency of 19 thrombosed veins (79 %) was restored with prompt symptomatic relief. An underlying anatomical anomaly or lesion was present in 13 patients: iliac vein compression syndrome (n = 8), absent (n = 2) or obstructed (n = 1) vena cava or venous stenosis (n = 2). Ten of the abnormalities were unknown before lysis and eight were relieved by stent deployment. Puncture site bleeding was the only complication but led to transfusion in 6 patients (25 %). Symptomatic reocclusion occurred in 4 patients. Catheter thrombolysis of iliofemoral vein thrombosis revealed many anatomical abnormalities which may predispose to thrombosis and are often amenable to stenting.