Endoluminal femoropopliteal bypass for intermittent claudication.
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OBJECTIVES: (i) to describe our initial clinical experience with endoluminal femoropopliteal bypass using a technique developed in a cadaveric model; (ii) to identify areas requiring technical modification to improve patency and complication rates. DESIGN: prospective, experimental pilot study. MATERIALS AND METHODS: fourteen consecutive patients with disabling intermittent claudication and superficial femoral artery occlusion underwent endarterectomy through a groin incision and endoluminal placement of a polytetrafluoroethylene graft. Follow-up was by duplex ultrasound and arteriography. RESULTS: two endovascular technical failures required conversion to open surgery. The cumulative primary (1 degrees), 1 degrees-assisted and secondary (2 degrees) patency rates at 1 year were 35.7%, 42.8% and 71.4% respectively; at 2 years the patency rates were 14.3%, 31.2% and 57.1%. Twenty-three endovascular interventions were required to maintain graft patency in 10 patients. Five patients subsequently required conventional bypass, of whom two proceeded to major amputation because of graft infection. Seven endovascular grafts remain patent at a mean follow-up of 50 months. CONCLUSIONS: this minimally invasive surgical technique is feasible, with acceptable patency rates. However, considerable investment of time and resources is required to maintain graft patency. With increasing experience and improved technical design, this procedure may offer a real alternative to conventional surgery in patients disabled by short-distance claudication. (+info)
Interobserver agreement in duplex scanning for vein grafts.
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BACKGROUND: although the precision of duplex scanning is of utmost importance in vein-graft surveillance, it has not been properly assessed. This study aims to analyse interobserver agreement on duplex scanning. METHODS: a blinded comparative trial of 69 infrainguinal vein bypass reconstructions. Two consecutive duplex scans were performed by different examiners and duplex ultrasound machines on the same patient. The duplex examinations were also compared with angiography, when available, and clinical follow-up. RESULTS: interobserver agreement in Kappa statistics was 0.69, signifying "good" agreement between the examinations in detecting haemodynamically significant changes in the grafts. The sensitivity, specificity and accuracy figures compared with a combination of angiography and follow-up data for the two scans were 80%, 91%, 88% and 85%, 93%, 91%, respectively. The limits of agreement were, however, wide for Doppler-derived velocity characteristics. CONCLUSION: duplex scanning is an accurate and reproducible method for detecting haemodynamically significant changes in infrainguinal vein grafts. (+info)
Utility and reliability of endovascular aortouniiliac with femorofemoral crossover graft for aortoiliac aneurysmal disease.
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OBJECTIVE: The purpose of this study was to determine the early efficacy of endovascular aortouniiliac stent grafts with femorofemoral bypass graft in the treatment of aortoiliac aneurysmal disease. METHODS: We analyzed 51 consecutive patients from January 1997 to March 1999 with a mean follow-up of 15.8 months. Patients ranged in age from 44 to 93 years (mean, 75 years) with a mean aortic aneurysm diameter of 6.2 cm. Technical success was achieved in 50 patients; one patient required conversion to open repair intraoperatively. We placed 28 custom-made and 22 commercial devices. The mean operative time was 223 minutes. The endograft was extended to the external iliac artery in 42% of cases. The contralateral common iliac artery was occluded using either a closed covered stent or intraluminal coils. RESULTS: The median hospital stay was 4 days with an average intensive care unit stay of 0.25 days. There were no operative mortalities. Two patients died during follow-up from unrelated conditions. Endoleaks occurred in 11 patients (22%); seven patients (14%) required intervention (four catheter based, three operative). Other complications occurred in 38% of patients but were largely remote or wound related. One femorofemoral bypass graft occluded immediately postoperatively as a result of an intraprocedural external iliac dissection yielding a 98% primary patency and 100% secondary patency. Clinical success was achieved in 88% of patients. CONCLUSIONS: These data suggest that this strategy represents a reliable method of repair of aortoiliac aneurysmal disease and extends the capability of an endoluminal approach to patients with complex iliac anatomy. (+info)
Incidence and treatment of intraoperative technical problems during endovascular repair of complex abdominal aortic aneurysms.
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PURPOSE: The purpose of this study was to assess the incidence and management of intraoperative technical problems during endovascular repair (EVR) of complex abdominal aortic aneurysms (AAA). METHODS: From February 1995 to March 1999, 204 EVRs of nonruptured AAA were performed at our institution. One hundred seventy-six patients had an in-house custom-made graft; 172 were aorto-uni-iliac grafts, and four were aortoaortic grafts. Twenty- eight patients had a bifurcated graft. One hundred fourteen patients (56%) were high risk for conventional open repair. One hundred nine patients (53%) were not suitable for most commercially available devices. RESULTS: Intraoperative technical problems occurred in 81 patients (40%). There were 37 endoleaks (27 proximal, 10 distal), 15 graft stenoses, one failure of graft deployment, two graft thromboses, three aortoiliac ruptures, five renal artery occlusions (one bilateral, four unilateral), and 18 internal iliac occlusions (five bilateral, 13 unilateral). Endovascular management of these problems was successful in 37 of the 81 patients (46%) and included 15 balloon dilatations, 21 additional stent placements, and one graft thrombectomy. Fifteen of the 81 patients (19%) had open procedures (four periaortic ligature placements, six open aneurysm repairs, three common iliac ligations, and two extra-anatomic bypass grafts). In the remaining 29 patients, the on-table problem was managed expectantly. During follow-up, two of 37 patients (5%) who were treated successfully with endovascular procedures experienced recurrence. There were five deaths (33%) among the 15 patients who underwent open procedures. CONCLUSION: Intraoperative problems occur frequently during the endovascular management of complex aneurysms. Many of these problems can be managed with additional endovascular techniques without an increased risk of recurrence or procedure-related complications. Open procedures in high-risk patients carry a high mortality rate. The team performing EVR of AAA should be skillful in advanced endovascular and open surgical procedures. (+info)
Association of sex with patency of femorodistal bypass grafts.
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OBJECTIVE: There is evidence for superior patency in infra-inguinal bypass procedures in men compared to women. A large, prospectively planned series was investigated in order to confirm this finding and to determine the origin of this difference in outcome. METHODS: Patients underwent femorodistal bypass surgery and a prospectively planned 12-month follow-up. Outcomes in male and female patients were compared and investigated for associations with characteristics of the patients and the surgical procedures. RESULTS: A total of 517 patients received femorodistal bypass grafts, including 424 vein grafts and 93 prosthetic and vein-prosthetic composite grafts. Patency was confirmed to be higher in male than in female patients (56% vs. 42%, p=0.005). Fewer male patients received prosthetic or composite grafts (21% vs. 33%, p=0.005), but the difference in patency was evident only in patients receiving vein grafts. Female patients were smaller, included fewer smokers (p<0.001) and had worse symptoms (p=0.03), but none of these characteristics explained the difference in outcome. Patency in vein grafts was associated with graft diameter (p=0.004), but graft diameter was not significantly associated with sex (p=0.09) or with body size. CONCLUSIONS: It was confirmed that patency of femorodistal bypasses is significantly higher in males than females. None of the factors investigated here explain this difference, but the greater use of prosthetic and composite grafts in female patients suggests that poorer vein quality should be investigated as a possible source of the inferior outcome in female patients. (+info)
Incidence of stenoses in femorodistal bypass vein grafts in a multicentre study.
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OBJECTIVES: To establish the incidence of graft stenosis in a large population of patients undergoing femorodistal bypass procedures and to investigate the differences in incidence between individual surgical centres and other subpopulations. PATIENTS AND METHODS: A total of 277 patients with femorodistal bypasses underwent duplex scanning of vein grafts for 12 months for the detection of graft stenoses. A standard definition of a significant stenosis was used in all twenty participating centres. RESULTS: Overall stenosis rate was 27%. Stenoses were more common in composite vein grafts (43%) than in single segment vein grafts (25%) p=0.05. Stenoses were more common in female patients (38%) than males (22%) p=0.02. Stenosis rates in individual centres entering more than 20 patients varied from 9% to 56%. In a multiple regression analysis only aspirin use, sex and centre were significant factors predicting the likelihood of graft stenosis. CONCLUSION: Female patients, those taking aspirin and patients with composite vein grafts appear to be more at risk of graft stenosis, but this does not fully explain wide variations in the incidence of stenoses reported by individual centres. (+info)
Application of the New York State PTCA mortality model in patients undergoing stent implantation.
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BACKGROUND: This study applied the New York State conventional coronary angioplasty (PTCA) model of clinical outcomes to evaluate whether it has relevance in the current era of stent implantation. The model was developed in 62 670 patients treated with conventional PTCA from 1991 to 1994 to risk adjust mortality and bypass surgery after PTCA. Since then, stents have become the dominant form of intervention. Whether that model remains relevant is uncertain. METHODS AND RESULTS: All patients undergoing stenting at the Mayo Clinic from 1995 to 1998 were analyzed for in-hospital mortality, bypass surgery performed after attempted stenting, and longer-term mortality. No patients were excluded. The New York model was used to risk adjust and predict in-hospital and follow-up mortality. There were 3761 patients with 4063 procedural admissions for stenting; 6,472 target vessel segments were attempted, and 96.1% of procedures were successful. With the New York multivariable risk factor equation, 79 in-hospital deaths were expected (1.95%); 66 deaths (1.62%) were observed. The New York model risk score in a logistic regression model was the most significant factor associated with in-hospital mortality (OR, 1.86; P<0.001). During a mean follow-up of 1.2+/-1.0 years, there were 154 deaths. Multivariable analysis documented 6 factors associated with subsequent mortality; New York risk score was the most significant (chi(2)=16.64, P=0.0001). CONCLUSIONS: Although the New York mortality model was developed in an era of conventional angioplasty, it remains relevant in patients undergoing stenting. The risk score derived from that model is the variable most significantly associated with not only in-hospital but also longer-term outcome. (+info)
Photoangioplasty: An emerging clinical cardiovascular role for photodynamic therapy.
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Photodynamic therapy (PDT) has been studied and applied to various disease processes. The potential of PDT for selective destruction of target tissues is especially appealing in cardiovascular disease, in which other existing interventional tools are somewhat nonselective and carry substantial risk of damage to the normal arterial wall. Enthusiasm for photoangioplasty (PDT of vascular de novo atherosclerotic and, potentially, restenotic lesions) is fueled by more effective second-generation photosensitizers and technological advances in endovascular light delivery. This excitement revolves around at least 4 significant attributes of light-activated therapy: the putative selectivity and safety of photoangioplasty, the potential for atraumatic and effective debulking of atheromatous plaque through a biological mechanism, the postulated capability to reduce or inhibit restenosis, and the potential to treat long segments of abnormal vessel by simply using fibers with longer light-emitting regions. The available nonclinical data, coupled with the observations of a new phase I trial in human peripheral atherosclerosis, suggest a promising future for photoangioplasty in the treatment of primary atherosclerosis and prevention of restenosis. (+info)