Elective popliteal aneurysms: does venous availability has an impact on indications?

AIM: The aim of this retrospective study was to evaluate the patency and limb salvage rates after prosthetics or venous bypasses for asymptomatic or mildly symptomatic popliteal aneurysms, in order to determine if small uncomplicated aneurysms (caliber <300%) should be operated or periodically controlled when a venous conduit is not available. METHODS: During a 18 years period, 100 popliteal aneurysms, including 85 asymptomatic and 15 associated with intermittent claudication, were operated on: group I consisted of 80 venous bypasses, and group II consisted of 20 prosthetic bypasses. RESULTS: Demographics and risks factors were similar in both groups. Local complications were more frequent in group I (17% vs 10% p=NS). Early vascular complications were rare in both groups. Late arterial complications were more frequent in group II. Primary patency, assisted primary patency, and secondary patency rates at 2 years were 94.3%, 97.3% and 98.7% in group I, and 61.5%, 89% and 88.4% in group II (p<0.05). In contrast, the limbs salvage rates were not significantly different for each type of graft (98.7% vs 100% p=NS). CONCLUSIONS: Our data shows that aneurysms treated with a prosthetic graft are at higher risk of late occlusion than those operated with a vein graft. This should be taken into account when facing a small uncomplicated aneurysm without available venous conduit. The presence of a suitable vein should be checked before deciding to operate a small uncomplicated popliteal aneurysm.

Technical aspects and current results of carotid stenting.

PURPOSE: We reviewed our experience with carotid stenting (CS), focusing on technical evolution and results. METHODS: From September 1995 to February 2000, 77 patients with 83 internal (n = 68) and common carotid artery lesions (n = 15) were selected for CS. This patient population was categorized into three consecutive periods based on patient selection, material, and technical skills. For internal carotid artery lesions, period I included 11 patients treated by means of direct carotid puncture with balloon expandable stents; period II included 42 patients treated by means of a femoral approach with self-expandable stents; and period III included 15 patients in whom monorail system and cerebral protection devices were used. Common carotid artery lesions were treated by means of carotid puncture in five patients and by means of a femoral approach in 10 patients. In only two of the latter cases, cerebral protection devices were used. RESULTS: The overall immediate success rate, defined as successfully treated stenosis with no neurological events, was 89.7% for internal carotid artery lesions and 100% for common carotid artery lesions. All neurological events, which consisted of reversible events (4.4%), minor stroke (1.5%), and major stroke (2.9%), occurred during periods I and II. In periods I, II, and III, the rate of surgical conversion was 18%, 9.5%, and 0%, respectively, the rate of transient ischemic attack and reversible ischemic neurologic deficit was 0%, 7%, and 0%, respectively, and the rate of minor and major stroke was 0%, 7%, and 0%, respectively. All major strokes were cleared with intra-arterial thrombolysis. At discharge, the success rates defined by means of the absence of conversion and neurological events were 82% during period I, 76% during period II, and 100% during period III. The freedom from neurological deficits rates were 100%, 97.6%, and 100%, respectively. During follow-up, six significant asymptomatic restenoses were detected with duplex scanning; however, only one patient required reintervention. CONCLUSION: Technical skills and technological improvement, including low-profile balloon and catheter, cerebral protection device, and intra-arterial rescue techniques, may reduce the rate of neurological events associated with CS. Technical improvements should be given careful consideration before the initiation of randomized trials comparing CS and carotid endarterectomy.

Percutaneous transluminal angioplasty in patients with ischemic tissue necrosis is worthwhile.

PURPOSE: Ischemic tissue necrosis is usually associated with long or sequential arterial obstructions. As a result, the role of percutaneous transluminal angioplasty (PTA), which addresses only short lesions, in patients presenting with trophic changes remains questionable. The purpose of this study was to evaluate the effectiveness of PTA in diabetic and non-diabetic patients presenting with grade 4 Fontaine's classification. METHOD: Between January 1992 and December 1997, 1352 patients with aorto-iliac and/or infrainguinal occlusive diseases were admitted to our institution. Three hundred and ten patients who presented with distal gangrene (95.5%) or ischemic ulcers (4.5%) were identified. The patients consisted of 117 diabetics and 193 non-diabetics. PTA alone was performed in 26 diabetics (group 1) and in 30 non-diabetics (group 2). Their charts were retrospectively reviewed and the patients were recalled for clinical examination and non-invasive monitoring. RESULTS: Follow-up was available for all patients and ranged from 1 to 4 years. The survival rate was significantly higher in diabetic patients than in non-diabetic patients (96% vs 77% at 1 year; p<0.05 and 91% vs 66% at 3 years; p<0.05). In group 1, the primary cumulative patency rate at 1 and 3 years was 76%. In group 2, the primary cumulative patency rate at 1 and 3 years were 85% and 80%, respectively. Three patients in group 1 required a redo PTA at 4 months, resulting in an assisted primary patency rate at 1 and 3 years of 88%. In contrast, no patients in group 2 required additional PTA. In group 1, the limb salvage rate at 1 and 3 years was 84%; and in group 2, 80% and 75%, respectively. CONCLUSION: The results of PTA in both groups were encouraging. Dilation of one or two short stenoses, despite multiple distal lesions, may improve distal flow sufficiently to promote wound healing. Thus, this procedure may be recommended in selected patients suffering from ischemic tissue loss. However, during the first 6 months following PTA, diabetic patients should be followed carefully with Duplex as they are prone to early restenosis.

Follow-up evaluation of endoluminally treated abdominal aortic aneurysms with duplex ultrasonography: validation with computed tomography.

OBJECTIVE: A growing number of patients with abdominal aortic aneurysms are currently being offered endoluminal treatment. However, the incidence of endoleaks, stenosis, and thrombosis is around 25% to 30%. As a result, a strict post procedure imaging surveillance protocol is necessary. The purpose of this study was to compare duplex ultrasonography (DU) and computed tomography (CT) for the follow-up of endoluminally treated aortic aneurysms. METHODS: A total of 89 patients were followed up with serial CT and DU at 1, 3, 6, 12, and 24 months after endoluminal treatment. Special attention was directed toward the presence of endoleaks and aneurysm diameter evolution. Preoperative CT and DU were also reviewed to assess aneurysm diameter correlation. RESULTS: With DU, 14 type I and 21 type II endoleaks were identified. In one case the DU did not visualize a type II endoleak present on CT, and CT did not confirm three type II leaks identified with DU. There was only one false positive for type I endoleak with DU. The sensitivity of DU was 96% with a specificity of 94%, when compared with CT. A linear regression analysis of the diameters obtained with DU and CT revealed a good correlation. However, variability was high, indicating poor agreement. Regarding diameter evolution, the range was identical in 45%, and the trend was similar in 73%. However, in 9% of the cases, DU showed a decrease in diameter, whereas CT showed a significant increase. CONCLUSION: DU is an accurate tool for the diagnosis of endoleaks, but is less valuable for diameter measurements, when compared with CT. Currently, DU is a useful tool, but CT remains a key part of the postoperative evaluation after endoluminal treatment of abdominal aortic aneurysms. At institutions where DU is used for follow-up, researchers should perform quality control studies to avoid potentially significant errors.

[Surgery of the internal carotid: locoregional or general anesthesia?]. / Chirurgie de la carotide interne: anesthésie locorégionale ou générale?

AIM OF THE STUDY: The aim of this retrospective study was to assess the advantages of regional anesthesia over general anesthesia in carotid artery surgery. PATIENTS AND METHOD: From January 1989 to December 1998, 670 patients with severe internal carotid artery stenosis were operated in the same center and were classified into two groups according to the type of anesthesia: group I, general anesthesia (n = 312) and group II, regional anesthesia (n = 358). Characteristics of the two groups were almost similar except for a higher rate of unstable heart disease in group I and bypass grafts in group II. RESULTS: A shunt was used in 16.3% of cases in group I and in 8.4% in group II. Complications resulting from the use of a shunt and intraoperative complications observed with regional anesthesia were reported. There was a conversion from regional to general anesthesia in 6 patients. Median duration of clamping was longer in group II (30 min vs 25 min). Cardiac complication rates were similar in the two groups, particularly cardiac mortality (0.6%). There were more pulmonary and miscellaneous complications in group I. Neurological complications were more frequent in group I, particularly fatal strokes (1% versus 0%). Neurological mortality and morbidity cumulative rates were 3.1% and 1.5%, respectively, not significantly different. CONCLUSION: These results, in agreement with those of the literature, confirm that carotid artery endarterectomy is associated with a low rate of neurological mortality and morbidity. Although regional anesthesia was associated with a lower rate of complications, we are not allowed to conclude to its superiority, as the present study was retrospective and the difference was not statistically significant.

Acute occlusion of popliteal and/or tibial arteries: the value of percutaneous treatment.

OBJECTIVES: to describe early and mid-term results with a percutaneous therapeutic protocol including thromboaspiration, thrombolysis, and correction of the underlying lesion by PTA. METHODS: thirty-three consecutive selected patients with recent (<1 month) reversible acute ischaemia associated with popliteal and/or tibial occlusion were studied. The primary endpoints were technical success (defined as residual mural thrombus less than 20% of the lumen and the presence of at least one tibial artery on angiogram), patient survival and limb salvage at 1 and 12 months. Secondary endpoints included complications, primary, assisted primary and secondary patency determined by duplex scan at 1, 6 and 12 months. RESULTS: technical success was achieved in 27 patients (82%). Twenty patients were treated by thrombo- aspiration+/-thrombolysis only, and seven required additional PTA (26%). In six patients (18%), percutaneous techniques failed, and embolectomy was performed in two, bypass in one and major amputations in three (9%). For the entire series, the survival rate was 100% at 1 month and 94% at 1 year. The limb salvage rate was 91% at 1 month and 1 year. The cumulative primary patency, assisted primary patency and secondary patency rates were 81%, 81% and 86% respectively at 1 month and 66%, 72% and 77%, respectively, at 12 months. Early complications occurred in 10 patients (30%): five groin haematomas (15%), four compartment syndromes (12%) and one haemoglobinuria (3%). CONCLUSION: percutaneous techniques offer excellent early and mid-term results in selected patients presenting with acute ischaemia with popliteal and/or tibial arteries occlusion.

[Metaplasia of aortic tissue into tracheal tissue. Surgical perspectives]. / Métaplasie de tissu aortique en tissu trachéal. Perspectives chirurgicales.

Tracheal reconstruction after extensive resection remains an unsolved surgical problem. Numerous attempts have been made using tracheal grafts or prosthetic conduits with disappointing results. In this study, we propose a new alternative using an aortic autograft as tracheal substitute. In a first series of experiments, a half circumference of two rings was replaced with an autologous carotid artery patch. In a second series, a complete segment of trachea was replaced with an autologous aortic graft supported by an endoluminal tracheal stent. No dehiscence or stenosis was observed. Microscopic examinations at 3 and 6 months showed the replacement of the aortic tissue by tracheal tissue comprising neoformation of cartilage and mucociliary or non-keratinizing metaplastic polystratified squamous epithelium. Although these results need to be confirmed by a larger series of experiments, they showed that a vascular tissue placed in a different environment with a different function can be submitted to a metaplastic transformation which tends to restore a normal structure adapted to its new function. These remarkable findings offer new perspectives in tracheal reconstruction in human.

Mid-term results of endovascular versus open repair for abdominal aortic aneurysm in patients anatomically suitable for endovascular repair.

OBJECTIVES: to prospectively evaluate the mid-term results of endovascular and open repair in patients with abdominal aortic aneurysm (AAA) anatomically suitable for endovascular repair. MATERIAL AND METHODS: between January 1995 and March 1999, among 438 patients treated for AAA, 180 (41%) were suitable for endovascular repair as assessed by computed tomography (CT) scan and angiogram. Seventy-three were treated by various commercially available endovascular grafts (EV) and 107 by open repair (OR). Postoperatively, patients were followed every 6 months with clinical examination, duplex scan and in the EV group, CT scans. Patients>> demographic data, intra- and postoperative events were recorded prospectively in a computerised database and compared for each group. RESULTS: median age, sex ratio, preoperative risk factors and aneurysm diameters were not statistically different between the two groups. Respectively in the EV and OR, the average duration of operation was 149+/-73 mn, and 133+/-44 mn (NS), blood loss 96 ml+/-28 and 985 ml+/-113 (p<0.01), duration of hospitalisation 7 days+/-2 and 13 days+/-7 (p<0.01). The one-month mortality was 2.7% (n=2) for EV and 2.8% (n=3) for OR. The rate of cardiac and pulmonary complications was significantly higher in the OR group (6. 9% versus 19.6%, p=0.017). At a mean follow-up of 1 year, the cumulative survival rate was 82.2%+/-7.5 for EV and 96%+/-2.12 for OR (log-rank test p=0.043). No patients died of rupture, but three patients had to be converted to open surgery. Twenty-two percent (n=16) patients in the EV and 7.5% (n=8) in the OR were submitted to a subsequent minor or major reintervention (p=0.007). At 1 year, the cumulative rates free of any reintervention were respectively 78. 8%+/-6.7% and 92.9%+/-2.7% (p=0.001). In the EV there were 17 early endoleaks (23.3%). At the end of patient's follow-up seven endoleaks (9.6%) persisted. The primary success rate defined by the absence of endoleak and the absence of reintervention was 54 (74%) with EV and 101 (94%) with OR (p=0.001). CONCLUSION: EV is a promising technique. However, with current devices and indications the immediate benefits, mainly less blood loss, fewer cardiac and pulmonary complications, and shorter hospitalisation time, are outweighed by a higher rate of reinterventions to treat endoleak, or to maintain patency of the graft.

Percutaneous stenting of an latrogenic superior mesenteric artery dissection complicating suprarenal aortic aneurysm repair.

PURPOSE: To report endovascular repair of an iatrogenic superior mesenteric artery (SMA) dissection caused by a balloon occlusion catheter. CASE REPORT: A 68-year-old man with a suprarenal aortic aneurysm underwent conventional prosthetic replacement, during which visceral artery back bleeding was controlled with balloon occlusion catheters. Six hours postoperatively, the patient experienced an episode of bloody diarrhea with abdominal pain and tenderness and mild metabolic acidosis. Colonoscopy revealed colitis (grade I) without necrosis of the right and left colon. An emergent abdominal computed tomographic scan showed signs of mesenteric ischemia with bowel dilatation and SMA wall hematoma; angiography identified a dissection 1 cm distal to the SMA origin. An Easy Wallstent was deployed percutaneously, successfully reestablishing SMA patency. The postoperative course was uneventful, and the patient remains asymptomatic with a patent SMA stent and aortic graft at 1 year. CONCLUSIONS: latrogenic SMA dissection should be suspected after suprarenal aortic aneurysm repair if signs of mesenteric ischemia arise. Prompt and thorough imaging studies are necessary to confirm the diagnosis and assess the potential for an endoluminal treatment.

[Radiation-induced aorto-ilio-femoral arterial arteritis. Mediocrity of the long-term results after conventional surgery]. / Artérites radiques aorto-ilio-fémorales. Médiocrité des résultats à long terme après chirurgie conventionnelle.

OBJECTIVES: To assess long-term outcome after surgical cure of radiation-induced aorto-ilio-femoral arterial occlusion and to deduce therapeutic indications. PATIENTS AND METHODS: Over a 20-year period, 15 patients were treated for occlusion of the aorto-ilio-femoral vessels 4 to 28 years after receiving radiotherapy. Primary treatment was medical (n=1), balloon dilatation (n=5), anatomic revascularization (n=5), and extra-anatomic bypass (n=4). Mean follow-up was 6.8 years. RESULTS: Among the 5 balloon dilatations, there was one failure requiring right axillofemoral bypass that was followed shortly by fatal septic shock; the 4 others have remained patent at 2 to 15 years, one having required stent dilatation at 6 months. Among the 5 patients who had anatomic revascularization, excepting on patient who died shortly after surgery from her cancer, all have required revision; 2 patients died of infection at 9 and 10 years; the two others are alive at 5 and 18 years. Among the 4 patients with extra-anatomic bypass (one aortothoracic-bifemoral bypass, two axillofemoral bypasses and one cross-over bypass), 2 died with prosthetic sepsis at 3 and 7 years and 2 others have had a bypass replacement. Overall, at last follow-up, half of the operated patients have died from infection (n=5) or cancer (n=2). DISCUSSION: In reports in the literature, revision and infection after conventional surgery is frequent. There is less risk with the endovascular approach, but it can be only applied for short occlusions. CONCLUSION: Excepting easily accessible occlusions with an apparent minimal risk for percutaneous balloon dilatation, irradiated arteries should be operated on only in case of severe ischemia. Patients with claudication should be treated conservatively because of the high risk of complications for prosthesis implantation with irradiated arteries.

The role of thrombolytic therapy in the management of paradoxical embolism.

Paradoxical emboli are considered a rare event, representing less than 2% of all arterial emboli. The most common intracardiac defect associated with paradoxical emboli is a patent foramen ovale. Most commonly, a pulmonary embolism is the cause of the acute increase in right atrial pressure leading to a reversal of intracardiac flow and passage of venous embolic material to the left heart. We present a patient with a pulmonary embolism and paradoxical emboli, and discuss therapeutic approach. We suggest that the treatment of choice for the patient with pulmonary embolism and non-limb-threatening acute ischemia due to a paradoxical emboli should be thrombolytic therapy and intracaval filter placement, followed by patent foramen ovale repair.

Endothelial dysfunction following thrombolysis in vitro.

OBJECTIVES: Thrombolytic therapy is frequently used to manage vascular graft thrombosis. However, long-term patency after thrombolysis remains poor. The purpose of this study was to characterise the morphological and functional response of endothelial cells (EC) exposed to a thrombus and subsequently lytic therapy. METHODS: Human EC were exposed to human whole blood thrombus for 2, 6, 12, and 24 h. The thrombus was lysed with urokinase. Cell morphology was studied with electron microscopy. Northern blot analyses were performed with human c-DNA probes for endothelin-1, thrombomodulin, tissue factor, tissue plasminogen activator, plasminogen activator inhibitor, and triose phosphate isomerase. RESULTS: EC retraction occurred for each period of incubation. Thrombomodulin expression was increased 2.2-fold at 6 h and 2.4-fold at 24 h. t-PA expression was depressed proportionally to the duration of thrombus exposure. PAI and TF expression transiently increased 1.5-fold at 2 h of exposure and returned to baseline at 6 h. Endothelin expression remained unchanged. CONCLUSIONS: Except for a transient increase in TF expression and reversal of the tPA/PAI ratio, EC exposed to thrombus do not appear to become actively procoagulant. The increase in TM expression may reflect enhanced thromboresistance. However, EC retraction may be responsible for an increase thrombogenicity of saphenous vein graft after thrombosis and Urokinase therapy.