Vena caval filter placement by intravascular ultrasound.

OBJECTIVE: Placement of vena caval filters under fluoroscopic surveillance incurs significant expense and potential risks associated with the transportation of critically ill patients. Intravascular ultrasound (IVUS) allows direct intraluminal visualization of the vena cava and the renal veins. The purpose of this study is to evaluate the accuracy of vena caval filter placement under IVUS in an animal model. METHODS: Fifteen Simon-Nitinol venal cava filters (C.R. Bard, Inc., Covington, GA) were placed under IVUS guidance into four anesthetized sheep. Twelve were placed transfemorally, and three were placed transjugularly. Accuracy of placement was confirmed with fluoroscopy by measurement between the filter tip and the targeted side branch. RESULTS: The vena caval filters placed femorally averaged 0.33+/-0.42 cm distance from the target vein side branch. Jugular approach filter placement was less accurate. Although two out of three filters placed from the jugular vein were correctly positioned, the distance from the target vein side branch was much greater averaging 2.5+/-1.04 cm. CONCLUSION: Femoral placement of vena caval filters under IVUS is extremely accurate. The transjugular route, however, was technically challenging and standard fluoroscopic vena caval filter placement appears to be more appropriate. Our success with the femoral approach merits further clinical investigation in the use of IVUS for critically ill patients that would benefit from bedside vena caval filter placement.

Remote superficial femoral artery endarterectomy: Multicenter medium-term results.

OBJECTIVE: The results of percutaneous transluminal angioplasty, atherectomy, and laser angioplasty for the treatment of long-segment (>10 cm) superficial femoral artery (SFA) occlusive disease have proved disappointing. Remote superficial femoral artery endarterectomy (RSFAE) is a minimally invasive procedure, performed through a single limited groin incision that may offer patency rates comparable with those of above-knee femoropopliteal (AKFP) bypass graft. In this retrospective multicenter study the medium-term results of RSFAE are examined. METHODS: Sixty patients were included in this study. Indications for the procedure were claudication in 52 patients and limb salvage in eight patients. RSFAE was performed with the MollRing Cutter device through a femoral arteriotomy. The distal "flap" of atheroma was anchored by balloon/stent angioplasty through the femoral arteriotomy. All patients underwent a follow-up examination with serial color flow ultrasound scanning. RESULTS: Ten patients with heavily calcified SFAs failed as "intentions to treat"; these patients underwent AKFP bypass grafting. The mean length of the endarterectomized SFAs was 22.3 cm (range, 8-37 cm). The primary cumulative patency rate by means of life-table analysis was 61.4% +/- 9% (SE), (mean, 12.9 months; range, 3-36 months). During follow-up, percutaneous transluminal angioplasty was necessary in 14 patients, for a primary-assisted patency rate of 82.6% +/- 8%. The locations of the restenoses after RSFAE were evenly distributed along the endarterectomized SFAs. There were no deaths and one wound complication (hematoma), and the mean hospital length of stay was 1.4 days +/- 0.8 days. CONCLUSIONS: RSFAE is a safe and moderately durable procedure. If long-term patency rates are similar to those of AKFP bypass graft, RSFAE may prove to be a minimally invasive adjunct for the treatment of SFA occlusive disease that will lower operative morbidity, reduce hospital LOS, and shorten recuperation.

Popliteal artery aneurysms: is endovascular reconstruction durable?

PURPOSE: To describe an endovascular method of performing femoropopliteal in situ saphenous vein (SV) bypass and popliteal artery aneurysm (PAA) embolization. METHODS: Twenty-two patients underwent PAA operations. Twelve patients had conventional SV bypasses with PAA proximal and distal ligation, whereas 10 underwent PAA embolization and an endovascular in situ SV bypass (EISB). The endovascular procedure was performed using an angioscopically guided side branch coil occlusion system. The PAAs were coil embolized under fluoroscopic surveillance. RESULTS: No deaths or wound complications occurred in the EISB group. The mean hospital length of stay (LOS) was 2.1 days. Seven EISB procedures were performed through 2 incisions, whereas 3 operations required an additional incision. One graft occluded at 3 months. All PAAs remained occluded by color-flow ultrasonography at follow-up ranging from 4 to 23 months (mean 13.6); cumulative primary patency was 89%. In the conventional bypass group, no deaths occurred, but 3 (25%) patients had wound complications. The mean LOS was 6.2 days, and 1 graft occluded, giving an 86% cumulative primary patency at 42 months. CONCLUSIONS: This minimally invasive technique obviates an extensive incision to harvest the SV and ligate the PAA proximally and distally. If long-term endovascular bypass graft patency and PAA occlusion rates prove to be similar to open operative results, the benefits of reduced wound complications, decreased hospital LOS, and increased health care savings support further investigation of this endovascular approach for the treatment of PAA.

Cryopreserved femoral vein grafts for difficult hemodialysis access.

Improved survival of patients with renal failure has led to the need for complex angioaccess procedures. The use of cryopreserved femoral vein for angioaccess when prosthetic arteriovenous grafts (AVG) could not be placed, owing to infection or the loss of conventional angioaccess sites from multiple AVG failures, was prospectively evaluated. Forty-eight cryopreserved femoral vein AVGs were placed in 44 patients. Thirty-eight (82%) of the cryopreserved femoral vein AVGs were placed for infection, whereas the other 10 (18%) were placed for multiple graft failures with compromised venous outflow. Even with implantation of the cryoveins into infected patients, there were no cryopreserved femoral vein AVG infections. The 1-year primary graft patency rate was 49% and the secondary graft patency rate was 75%. During the same time interval, 68 prosthetic brachial artery-to-axillary vein AVGs were placed. The 1-year primary and secondary patency rates for the prosthetic AVGs were 65 and 78%, respectively. In this study the overall patency rate of the cryopreserved femoral vein AVGs was similar to that for the PTFE AVGs (p = 0.519). In conclusion, the cryopreserved femoral vein proved useful in difficult angioaccess cases. The lack of infection after cryovein implantation around an infected area shows promise for salvaging an angioaccess site that would otherwise have been abandoned.

Comparison between the transabdominal and retroperitoneal approaches for aortic reconstruction in patients at high risk.

PURPOSE: The purpose of this study was to compare the transabdominal approach with the retroperitoneal approach for elective aortic reconstruction in the patient who is at high risk. METHODS: From January 1992 through January 1997, 148 patients underwent aortic operations: 92 of the patients were classified as American Society of Anesthesia (ASA) class IV. Forty-four operations on the patients of ASA class IV were performed with the transabdominal approach (25 for abdominal aortic aneurysms and 19 for aortoiliac occlusive disease), and 48 operations were performed with the retroperitoneal approach (27 for abdominal aortic aneurysms and 21 for aortoiliac occlusive disease). There were no significant differences between the groups for comorbid risk factors or perioperative care. RESULTS: Among the patients of ASA class IV, eight (8.7%) died after operation (retroperitoneal, 3 [6.26%]; transabdominal, 5 [11.3%]; P =.5). There was no difference between groups in the number of pulmonary complications (retroperitoneal, 23 [47.9%]; transabdominal, 19 [43.2%]; P =.7) or in the development of incisional hernias (retroperitoneal, 6 [12.5%]; transabdominal, 5 [11.3%]; P =.5). The retroperitoneal approach was associated with a significant reduction in cardiac complications (retroperitoneal, 6 [12.5%]; transabdominal, 10 [22.7%]; P =.004) and in gastrointestinal complications (retroperitoneal, 5 [8.3%]; transabdominal, 15 [34.1%]). Operative time was significantly longer in the retroperitoneal group (retroperitoneal, 3.35 hours; transabdominal, 2.98 hours; P =.006), as was blood loss (retroperitoneal, 803 mL; transabdominal, 647 mL; P =.012). The patients in the retroperitoneal group required less intravenous narcotics (retroperitoneal, 36.6 +/- 21 mg; transabdominal, 49.5 +/- 28.5 mg; P =.004) and less epidural analgesics (retroperitoneal, 39.5 +/- 6.4 mg; transabdominal, 56.6 +/- 9.5 mg; P =.004). Hospital length of stay (retroperitoneal, 7.2 +/- 1.6 days; transabdominal, 12.8 +/- 2.3 days; P =.024) and hospital charges (retroperitoneal, $35,587 +/- $980; transabdominal, $54,832 +/- $1105; P =.04) were significantly lower in the retroperitoneal group. The survival rates at the 40-month follow-up period were similar between the groups (retroperitoneal, 81.3%; transabdominal, 78.7%; P =.53). CONCLUSION: In this subset of patients who were at high risk for aortic reconstruction, the postoperative complications were common. However, the number of complications was significantly lower in the retroperitoneal group. Aortic reconstruction in patients of ASA class IV appears to be more safely and economically performed with the retroperitoneal approach.

Minimally invasive in situ bypass.

Since the report of a successful femoropopliteal in situ saphenous vein bypass in 1962, surgeons have attempted to make this bypass a less invasive operation and simplify the two principal technical components of the operation: (1) rendering the saphenous vein valves incompetent and (2) occluding the venous side branches. To accomplish this bypass, however, a long incision that is the length of the leg over the course of the saphenous vein is often necessary, which can be fraught with hazard, especially in patients with diabetes in whom wound complications can be devastating. An angioscopically assisted technique that allows the surgeon to perform valvulotomy and occlude venous side branches from within the saphenous vein--a minimally invasive in situ vein bypass--has been developed. This article discusses preclinical, fluoroscopic clinical, and angioscopic clinical studies of minimally invasive in situ bypass.

Transposed basilic vein versus polytetrafluorethylene for brachial-axillary arteriovenous fistulas.

BACKGROUND: Both transposed basilic vein (BV) and polytetrafluorethylene (PTFE) upper arm arteriovenous fistulas (AVF) are common angioaccess operations. To evaluate the patency and complication rates after AVF, a concurrent series of patients was reviewed. METHODS: Ninety-eight patients underwent brachial artery to axillary vein AVF: 30 BV and 68 PTFE. The PTFE grafts were performed in the standard fashion, whereas the basilic veins were translocated subcutaneously to the brachial artery. RESULTS: Risk factors were similar between the two groups. Basilic vein AVF had better patency at 24 months (70% BV versus 46% PTFE, P = 0.023). The dialysis access complications were higher in the BV group (20%) versus PTFE (5%), but the PTFE group had a higher infection rate (10%) than BV (0%). CONCLUSIONS: The primary and secondary patency rates were superior in the BV AVFs. The BV AVF preserves the venous outflow tract after AVF thrombosis for a future PTFE AVF operation.

Iliofemoral venous thrombosis caused by compression of an internal iliac artery aneurysm: a minimally invasive treatment.

PURPOSE: To report the success of a minimally invasive treatment for phlegmasia cerulea dolens without gangrene caused by compression from an internal iliac artery aneurysm. METHODS AND RESULTS: An 81-year-old male with a 1-month history of paralysis owing to a hemorrhagic stroke presented with massive edema and skin mottling of the right lower extremity. Imaging confirmed right iliofemoral deep vein thrombosis caused by compression from a 4-cm internal iliac artery aneurysm. With thrombolysis ruled out, a minimally invasive treatment plan was undertaken, featuring percutaneous coil embolization of the aneurysm and surgical venous thrombectomy with proximal arteriovenous fistula creation and iliac vein stent placement. Failure of the coils to embolize the iliac aneurysm prompted the use of an endovascular graft to exclude the aneurysm. The patient's symptoms subsided, and he has a patent right iliofemoral venous system and internal iliac artery at his latest (16-month) follow-up. CONCLUSIONS: This case demonstrates that minimally invasive endovascular and open techniques can be combined to achieve an optimum outcome in patients at high risk for standard surgical approaches.

Popliteal artery aneurysm treated with a minimally invasive endovascular approach: an initial report.

PURPOSE: To report a minimally invasive approach to popliteal artery aneurysm (PAA) treatment. METHODS AND RESULTS: A 48-year-old male with a 3-cm PAA was treated electively with an endovascular in situ saphenous vein bypass and transluminal antegrade coil embolization of the PAA prior to completion of the proximal anastomosis. Two short incisions at the anastomosis sites resulted in no wound complications, and the patient was discharged after 2 days. After 14 months of follow-up, the patient is asymptomatic with continued patency of the in situ bypass and occlusion of the PAA. CONCLUSIONS: This endovascular approach for minimally invasive femoropopliteal in situ saphenous vein bypass grafting appears feasible for treatment of PAAs. This method may reduce the rate of wound complications attending classic open in situ bypass grafts.

Should vein be saved for future operations? A 15-year review of infrainguinal bypasses and the subsequent need for autogenous vein.

The decision to use prosthetic or autogenous vein as the initial conduit for first-time vascular bypass of the lower extremity depends in part on the likelihood of subsequent need for autogenous conduit for another leg or heart bypass. The true frequency of these later events is not known. To answer this question, we analyzed a database of infrainguinal and coronary artery bypasses (CABG) performed at one institution between January 1980 and July 1995, to determine how many patients required subsequent infrainguinal bypass or CABG after their initial leg bypass. Five hundred and seventy-two infrainguinal bypasses were performed on 440 patients (mean age 63.9); average follow-up was 5.6 years. The clinical philosophy favored autogenous vein for first bypass, which was used in 84% of first operations performed during the study period while prosthetic material was used in 16%. For patients in which vein was used for the first operation, and who went on to have a second operation, the use of prosthetic conduit rose from 16% of operations to 27% (p < 0.05). The rate of subsequent CABG after leg bypass was very low, 2% at 5 years, 3% at 10 years. The cumulative probability of requiring a subsequent infrainguinal bypass was 27% at 5 years, 32% at 10 years. Of these, 46% were ipsilateral and 54% were contralateral. Considering only subsequent tibial bypasses (where vein might be considered obligatory), the cumulative 5-year rate of subsequent leg bypass was only 13%. Another bypass was most likely to occur within the first 3 years, rarely thereafter. In summary, after primary infrainguinal bypass, additional procedures using vein may arise in 1/4 to 1/3 of patients, mostly in the first 3 years. However, only 13% will definitely need vein for tibial bypass in 5 years, and subsequent CABG is uncommon.

Diagnosis of aortocaval fistula by computed tomography.

A case of an aortocaval fistula documented by contrast-enhancement computed tomography is reported. In the presence of a large abdominal aortic aneurysm, the computed tomography (CT) triad findings of: (1) vena caval effacement, (2) loss of the fat plane between the aorta and vena cava, and (3) rapid flow of contrast from the aorta into a dilated inferior vena cava is characteristic of an aortocaval fistula.

The limits of generalized cardiac screening tests for predicting cardiac complications after infrainguinal arterial reconstruction.

We examined the relative efficacies of different cardiac screening strategies for infrainguinal arterial bypass. The outcomes of 205 elective leg bypass procedures over a 10-year period, including myocardial infarction (MI), total cardiac complications, and mortality were tallied. Clinical risk factors popularized by Goldman and Eagle, and the results of dipyridamole thallium myocardial imaging (DThal) were recorded. The overall mortality rate was 3.4%, with a 3.4% incidence of MI and a 5.4% total cardiac complication rate. Both abnormal DThal (p = 0.011) and Goldman class II-IV (p = 0.030) were significant predictors of MI and cardiac death, but both suffered from poor specificity and positive predictive value. Because logistic regression analysis identified a correlation between angina, CHF, and an abnormal DThal, a customized screening strategy was developed to include the presence of angina, CHF and an abnormal DThal. Eighty-eight percent of patients suffering MI or death met these criteria, while only 11% of the complication-free group did. This screening strategy provided a superior sensitivity of 88%, specificity of 89%, positive predictive value of 25%, and 99% negative predictive value. A customized screening strategy (angina, CHF, abnormal DThal), developed from a 10-year experience with a single patient group, provided better predictive accuracy than any generalized screening formula.

Traumatic carotid artery dissection and pseudoaneurysm treated with endovascular coils and stent.

PURPOSE: To report a case of post-traumatic internal carotid artery dissection and pseudoaneurysm formation at the C-1 level successfully treated by a percutaneous endovascular technique. METHODS AND RESULTS: A 20-year-old female presented 72 hours after a motor vehicle accident with incomplete occulosympathetic paresis (Horner's syndrome), carotidynia, and leftsided 1.5-cm x 2.5-cm pseudoaneurysm at the C-1 level. Neuroradiologists embolized the pseudoaneurysm with Guglielmi detachable coils and controlled the dissection with placement of a Wallstent. CONCLUSIONS: This report illustrates successful percutaneous endovascular treatment of a carotid dissection and pseudoaneurysm near the base of the skull.