Endotension after endovascular aneurysm repair: the Ancure experience

PURPOSE

The expansion of aneurysms after endovascular repair is a consequence of persistent sac pressure, usually resulting from an endoleak. Several authors have suggested that sac expansion can occur even in the absence of endoleak, referring to this phenomenon as endotension. This study undertakes a review of the largest US endograft trial data to better define the significance of aneurysm expansion in the absence of endoleak.

METHODS

The core laboratory imaging database from the Ancure (Guidant) endovascular graft Phase I and Phase II trials approved by the Food and Drug Administration was reviewed with attention to aneurysm size and endoleak. Aneurysm size was measured with standardized two-dimensional computed tomography (CT) scan at the area of largest initial aneurysm diameter. Endoleak was detected with CT scans, color duplex ultrasound scans, and angiography in selected cases. Patients were evaluated at baseline, 3 months, 6 months, 12 months, and every 12 months thereafter. An endograft was classified as leaking if any endoleak was detected with any modality at any time point.

RESULTS

A total of 658 patients were entered into these protocols and the data submitted to the core laboratory. A control group of 120 conventional aortic patients and a group of 62 without baseline CT data were excluded from further analysis. Of the remaining 476 patients, 144 (60 tube, 60 bifurcated, and 24 mono-iliac) were free of endoleak at all intervals and had baseline CT measurements to allow comparison. Overall, the average size decrease in this nonleaking group was 9.9 +/- 9.4 mm (range, -50.6-11.1 mm) at a mean follow-up of 23.3 months. Evaluation for overall aneurysm expansion revealed 17 patients who had an increase of 2.3 +/- 2.9 mm (range, 0.3-11.1 mm) at a mean follow-up of 14.1 months. Only two patients without evidence of endoleak exhibited growth of more than 5 mm at maximum follow-up (7.6 mm at 12 months and 11.1 mm at 36 months). Additional analysis of sealed endoleaks and late endoleaks failed to demonstrate any group with expansion in the absence of detectable endoleak.

CONCLUSIONS

Endotension appears to be rare in this large series of prospectively evaluated endografts. From this review, endotension seems more likely to represent missed endoleak than true aneurysm expansion in the absence of perigraft flow.

Steal syndrome complicating hemodialysis access procedures: can it be predicted?

The development of steal syndrome distal to an arteriovenous fistula (AVF) created for hemodialysis access remains a significant clinical problem. This study was undertaken to determine the role of intraoperative noninvasive testing in the prediction and management of steal syndrome following arteriovenous fistula creation. First, in order to determine a threshold digital/brachial index (DBI) for patients at risk for steal syndrome, we performed a retrospective review of patients who had had the DBI measured and who developed symptoms (steal syndrome) following AVF creation. This was followed by a prospective evaluation of the ability of the DBI to predict which patients undergoing AVF surgery would develop steal syndrome. A DBI of <0.6 identifies a patient at risk for steal syndrome. Intraoperative DBI cannot be used to predict which patient will develop steal syndrome; however, if revision is indicated, the DBI should be increased to >0.6. Failure to accomplish this puts the patient at risk for continued steal syndrome.

Duplex directed caval filter insertion in multi-trauma and critically ill patients

This study was undertaken to determine the safety and feasibility of inferior vena cava (IVC) filter insertion at the bedside using duplex imaging in multi-trauma and/or critically ill patients. From February 1996 to August 1997, 53 multi-trauma and/or critically ill patients, who were in the intensive care unit and referred for an IVC filter, were prospectively evaluated for possible duplex directed caval filter (DDCF) insertion. Screening IVC duplex scans were performed in all patients. Satisfactory ultrasound visualization in 46 patients (87%) allowed attempted DDCF insertion. All procedures were percutaneously performed at the bedside using Vena Tech IVC filters. The results from this series showed that DDCF insertion can be safely and rapidly performed at the bedside in multi-trauma or critically ill patients. The procedure is dependent on satisfactory visualization of the IVC by duplex ultrasonography, which was possible in 45 out of 53 (85%) patients. Insertion at the bedside substantially reduces the procedural cost and avoids the need for transport, radiation exposure, and intravenous contrast.

Subfascial perforator vein ablation: comparison of open versus endoscopic techniques

PURPOSE

To compare the outcomes and complications of open (OSPS) versus endoscopic subfascial perforator surgery (SEPS) for treatment of chronic venous insufficiency.

METHODS

Data were retrospectively collected on 25 patients who underwent 27 SEPSs from February 1996 to August 1997 and from 22 patients who underwent 29 OSPSs between March 1978 and May 1993. Outcomes were evaluated for postoperative complications, ulcer healing, recurrence, and venous dysfunction scores on the last follow-up for the SEPS group and at 1-year follow-up for the OSPS group.

RESULTS

The 2 groups were similar in age, sex, history of previous venous surgery, healed or active ulcers, etiology, deep venous incompetency, pathophysiology, and venous refill times. Eighteen (90%) of 20 active ulcers in the SEPS group healed with recurrences in 5 (28%) limbs at 7.5 +/- 5.4-month follow-up. All 19 ulcers in the OSPS group healed, with recurrences in 13 (68%) limbs at 35 +/- 35-month follow-up. Clinical venous dysfunction scores showed significant improvement following SEPS (10.0 +/- 3.6 to 5.4 +/- 4.1, p < 0.001) and OSPS (10.0 +/- 3.2 to 6.7 +/- 3.6, p < 0.001) with no significant difference between groups. Both groups also had significant improvement in anatomical and disability scores. There was no postoperative mortality in either group. The OSPS group had significantly more wound complications (45%) than the SEPS group (7%) (p < 0.005). The hospital stay and readmission rate for wound problems were also higher in the OSPS group.

CONCLUSIONS

The early outcome showed equal improvement in clinical venous dysfunction scores in the 2 groups, but with significantly fewer complications in the SEPS group. Although the long-term durability of the endoscopic approach has not been determined, the short-term results would favor SEPS for treatment of severe venous insufficiency when perforator incompetence is a significant component.

Endoleak after aortic stent graft repair: diagnosis by color duplex ultrasound scan versus computed tomography scan

PURPOSE

The purpose of this study was to compare the accuracy of a color duplex ultrasound scan (CDU) to a computerized axial tomography scan (CT) in the diagnosis of endoleaks after stent graft repair of abdominal aortic aneurysms.

METHODS

The Endovascular Aneurysm Clinical Trial Core Laboratory records were reviewed from 117 concurrent CDU and CT studies that were performed in 79 patients who were implanted with the Endovascular Technologies stent graft device between December 1995 and January 1997. All of the studies were interpreted by the Core Laboratory as having the presence or the absence of an endoleak or as being indeterminate because of technical factors. Of the 117 videotaped CDU studies available for reexamination, 100 were reassessed for technical adequacy on the basis of the following criteria: a satisfactory imaging of the aneurysm sac and of the stent graft with gray scale, and both color and spectral Doppler scan evaluation for endoleak outside the endograft and within the aneurysm sac.

RESULTS

Of the 117 studies, 103 CDUs (88%) and 114 CTs (97%) were recorded as having the presence or the absence of an endoleak and 14 CDUs (12%) and 3 CTs (3%) were indeterminate. For the studies that were recorded to have the presence or the absence of an endoleak, the sensitivity, the specificity, the positive and the negative predictive values, and the accuracy of CDUs as compared with CTs were 97%, 74%, 66%, 98%, and 82%, respectively. Of the 100 CDU videotaped studies available for review, the following results were seen: (1) 93 CDUs had satisfactory B-mode images, (2) 76 had satisfactory color Doppler scan images to evaluate for endoleaks, (3) 55 had color Doppler scan assessment of the entire abdominal aortic aneurysm sac for endoleak, and (4) 27 had spectral Doppler scan waveform confirmation of suspected endoleaks. Only 19 CDU studies (19%) with all 4 criteria for complete assessment of endoleak were performed.

CONCLUSION

Although most of the CDU studies were technically suboptimal, the CDUs reliably identified endoleaks with an excellent sensitivity and a negative predictive value as compared with CT scans.

A comparison of surgery for neurogenic thoracic outlet syndrome between laborers and nonlaborers

OBJECTIVE

To determine factors of outcome following surgical intervention for neurologic thoracic outlet syndrome (NTOS).

METHODS

In a retrospective study of patients surgically treated for NTOS, outcome was evaluated by postoperative symptoms and the ability of patients to return to work.

RESULTS

Good, fair, and poor results were obtained in 26 (48%), 21 (39%), and 7 (13%) patients, respectively. The best predictor of a good outcome was occupation. Nonlaborers were more likely to have good outcome (21 of 32, 66%) when compared with laborers (5 of 22, 23%; P = 0.0025). Only 6 of 20 (30%) laborers were able to return to their original occupation compared with 17 of 26 (65%) nonlaborers (P = 0.036).

CONCLUSIONS

Laborers with NTOS are less likely to have a good result from surgical intervention, are unlikely to return to their original occupation, and may require retraining for a non-labor-intensive occupation if they cannot return to their original work.

Long-term outcome after early infrainguinal graft failure

PURPOSE

To determine the long-term outcome and prognostic factors after early infrainguinal graft failure (< 30 days).

METHODS

Retrospective analysis of limb salvage data, patency data, and prognostic risk factors in 112 new infrainguinal bypass grafts from 1985 to 1995 that occluded within 30 days of operation.

RESULT

Thirty-six femoropopliteal and 76 femorotibial/femoropedal arterial bypass ("index") procedures were performed for rest pain (50%), tissue loss (31%), or disabling claudication (19%). In 103 patients, an immediate additional revascularization ("takeback") procedure was performed at the time of early graft failure. Life table analysis of the takeback procedures for threatened limbs (n = 84) revealed limb salvage rates of 74%, 54%, 40%, and 31% at 1 month, 1 year, 3 years, and 5 years, respectively. The 1-month limb salvage rate (threatened limbs) was 12% (1 of 8) in patients who were not taken back for revascularization and 33% (4 of 12) in patients who had undergone more than one takeback procedure within 30 days. The secondary graft patency rates for the takeback procedures (n = 103) were 70%, 37%, 27%, and 23% at 1 month, 1 year, 3 years, and 5 years, respectively. Univariate and life table analysis revealed that patients who were given anticoagulation medication after the index procedure (before graft thrombosis) or patients who had undergone previous ipsilateral leg revascularization had significantly lower rates of limb salvage and graft patency (p < 0.05). The limb salvage rate was also significantly worse in patients who had single-vessel runoff compared with those who had multiple-vessel runoff (p < 0.01). Thrombectomy and revision or complete graft replacement had a better secondary patency rate than thrombectomy alone (p < 0.05). Autogenous vein grafts had better outcome than polytetrafluoroethylene-containing grafts, but statistical significance was not achieved. No significant differences in limb salvage or graft patency rates were found between femoropopliteal versus femorotibial/femoropedal bypass grafting, age, gender, previous inflow surgery, diabetes, hypertension, smoking, or cardiac, renal, or pulmonary disease.

CONCLUSION

The long-term limb salvage and graft patency rates after takeback revascularization procedures for early graft failure are poor. Despite poor outcome, a single takeback procedure appears warranted in all patients. Multiple takeback procedures, however, do not appear to be justified, especially in patients who are given anticoagulation medication after the index bypass procedure, repeat leg bypass procedures, or if there is no potential for graft revision.

Blunt injury of the abdominal aorta: a review

Injury to the abdominal aorta after blunt trauma occurs much less frequently than injury to the thoracic aorta. Although presentations vary, common themes continue to emerge with each patient. Within a 6-month period, our trauma unit diagnosed and treated two cases of blunt abdominal aortic trauma. Both patients were restrained passengers in motor vehicle crashes with resultant abdominal aortic injuries and demonstrated some of the most common associated injuries. Our two cases bring the number found in the literature to 62 and demonstrate the need for rapid recognition and treatment of this potentially lethal injury. This article is a comprehensive review of the management of abdominal aortic injury from blunt trauma.

A new technique for hemodialysis access surgery: use of the pneumatic tourniquet

The purpose of this study was to determine whether tourniquet occlusion could be safely used on the upper extremity for vascular control during hemodialysis access surgery. The hospital and outpatient records of 44 patients undergoing 105 hemodialysis access procedures were retrospectively reviewed. In 48 procedures tourniquet occlusion was used for vascular control, whereas in 57 procedures vascular clamps were used. In those procedures in which the tourniquet was used, the mean tourniquet time was 30 minutes and the mean tourniquet pressure was 242 mm Hg. The operative time was significantly less in the tourniquet group as compared to the clamp group (72.5 minutes vs. 84 minutes, respectively; p = 0.029). There was no statistically significant difference in the incidence of nerve injury, bleeding, hematoma, vascular steal, infection, or swelling between the two groups. There were no complications related specifically to the use of the tourniquet. There was no difference in primary patency in comparing the tourniquet control group with the clamp control group (p > 0.5). The use of a pneumatic tourniquet for vascular control during hemodialysis access surgery allows for a faster, technically easier operation with no increase in the complication rate and no effect on primary patency.

Coexistent abdominal aortic aneurysm and renal carcinoma: management options

Renal carcinoma (RCA) presenting in association with abdominal aortic aneurysm (AAA) is extremely rare, with only sporadic case reports previously described. The management of six cases of AAA and concomitant RCA presenting to a single institution from March, 1991 through December, 1993 was reviewed and management options considered. AAAs ranged in size from 4.5-7.0 cm (mean, 5.6 cm). Three left renal carcinomas were resected via a retroperitoneal approach simultaneous to repair of the AAA. One right renal carcinoma was resected in combination with repair of an AAA through a transperitoneal approach. The fifth case was managed by left nephrectomy, followed by interval aneurysmectomy, and the sixth case was managed by nonsurgical methods because of the presence of widely metastatic disease. Renal malignancies included five renal cell carcinomas and one transitional cell carcinoma. Three patients remain free of disease 8-11 months postoperatively, and one patient had metastatic disease detected 19 months postoperatively. Two deaths have occurred; one due to a massive CVA 1 month following a combined aneurysmectomy and left nephrectomy, and a second due to unknown etiology in the patient managed non-surgically. No peripheral vascular or aortic graft related complications have occurred. The treatment of AAA and RCA should be governed by the size of the AAA, the location of the cancer, and the extent of malignant disease. Simultaneous resection is safe and effective in patients with coexistent AAA and renal cancer. Left sided tumors should be resected via a retroperitoneal approach that also provides excellent exposure for simultaneous AAA resection.(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative iliac artery stents: combination with infra-inguinal revascularization procedures

Iliac artery percutaneous transluminal angioplasty (PTA) can effectively provide in-flow for subsequent distal vascular reconstruction. Iliac artery stents may improve the initial hemodynamics and long term patency of PTA, and thus may be well-suited for combined proximal PTA with distal bypass procedures. This report reviews our preliminary experience with iliac artery stenting in combination with infra-inguinal vascular reconstruction. Thirteen iliac artery stent procedures combined with simultaneous distal revascularization were performed in 11 patients. Ten procedures were performed for limb salvage, two for disabling claudication, and one before planned orthopedic surgery. Distal revascularization procedures included seven femoropopliteal, four femorotibial bypasses, one common femoral endarterectomy, and one thrombectomy of a femoropopliteal bypass. Stent placement was technically successful in all patients. Mean pre-operative ankle-brachial index (ABI) was 0.41 (+/- 0.28), which improved to 0.91 (+/- 0.18) post-operatively (P < 0.0001). Mean systolic iliac artery gradients across the lesions improved from 27.1 (+/- 9.8) mm Hg to 2.7 (+/- 3.4) mm Hg after stent placement (P < 0.0001). Mean follow-up is 5.8 months (range 1-12 months). Two femoropopliteal bypass grafts occluded in the follow-up period. One occlusion was caused by a mid-vein graft stenosis that was repaired with subsequent graft patency. The other graft occlusion occurred in a patient with rest pain who did not require a second bypass procedure, as the ABI increased from 0.3 to 0.7 following stent placement with resolution of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Vein harvest ischemia: a peripheral vascular complication of coronary artery bypass grafting

Lower-extremity ischemia can lead to impaired healing of saphenous vein excision sites in patients with significant peripheral vascular disease (PVD). Five patients who required infrainguinal revascularization for wound necrosis of the harvest site after coronary artery bypass grafting are described. The male/female ratio was 2:3 with a mean age of 67 (range 45-87) years. The most commonly associated problems were insulin-dependent diabetes mellitus (80%) and congestive heart failure (60%). The saphenous vein was harvested from the thigh and leg in three patients and exclusively from the leg in the others. Manifestations of ischemia ranged from persistent ulceration to complete wound disruption threatening limb loss. Impaired healing was isolated to infragenicular wounds in all patients. Pedal pulses were not detected in any of the affected extremities. Determination of the ankle/brachial pressure indices (ABI) revealed values of < 0.5 in three affected limbs. Non-compressible vessels resulted in falsely raised ABI of > 1.0 in the remaining two limbs; however, Doppler waveform analysis in these patients demonstrated significant PVD. Aggressive wound care and antibiotic therapy were continued for mean of 9 weeks before operative intervention. Infrainguinal reconstruction included femoropopliteal (two), femorotibial (two) and popliteal-tibial bypass (one). Autologous arm and saphenous veins in addition to expanded polytetrafluoroethylene grafts were used effectively. Limb salvage and wound healing were achieved in 100% of the patients without untoward sequelae. It is concluded that unrecognized PVD in patients undergoing coronary artery bypass grafting can lead to significant morbidity. Patients at risk may be identified with a combination of history, physical examination and non-invasive testing.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term follow-up for recurrent stenosis: a prospective randomized study of expanded polytetrafluoroethylene patch angioplasty versus primary closure after carotid endarterectomy

PURPOSE

To determine the effect of primary closure (PC) versus expanded polytetrafluoroethylene patch graft angioplasty (PGA) on the incidence of recurrent stenosis (> 50% lumen diameter narrowing) after carotid endarterectomy (CEA), 87 patients undergoing 100 consecutive CEA were prospectively randomized into two groups.

METHODS

Forty-four patients underwent 51 PC, and 43 patients underwent 49 PGA. All patients were evaluated after operation by duplex scanning at 1.5, 12, 24, and 36 months. There were no significant differences in the demographic characteristics or operative indications for CEA between the two patient groups. Complete follow-up was achieved in 86% (75/87) of the patients during the 36-month surveillance period.

RESULTS

The perioperative permanent neurologic morbidity in the PC and PGA groups was noted to be 4% and 2%, respectively (PC = 2/51 vs PGA = 1/49, p = 0.58). Three additional reversible cerebral ischemic events occurred in the postoperative period (PC = 2/51 vs PGA = 1/49, p = 0.58). Other morbidity included immediate postoperative hemorrhage requiring reexploration (1/51) in the PC group and an infected expanded polytetrafluoroethylene patch requiring removal and replacement with autogenous vein (1/49). Long-term follow-up detected a single patient with significant bilateral restenoses of his primarily closed carotid arteries. None of the patients in the PGA group had restenoses (PC = 2/51 vs 0/49, p = 0.50). In addition, no postoperative dilation of the common or internal carotid arteries or perioperative death was observed.

CONCLUSIONS

In patients undergoing CEA, these data demonstrate no significant difference in the perioperative morbidity or mortality between PC and PGA. Use of the patch did not engender patients to patch rupture or aneurysmal degeneration as previously described with vein patch angioplasty procedures. This series supports effective use of either technique to achieve minimal rates of restenosis.

Angioscopic evaluation of valvular disruption during in situ saphenous vein bypass

Several valvulotomes are currently available to achieve valvular disruption; however, studies comparing the efficacy of these endoluminal instruments are lacking. This prospective study evaluates the efficacy and safety of the three most commonly employed valve cutters: the Hall, LeMaitre, and Mills valvulotomes. A total of 30 in situ greater saphenous vein bypass grafts were included in this investigation. Valvular disruption was attempted with either the LeMaitre (11 cases), Hall (12 cases), or Mills (7 cases) valvulotomes. Subsequently, angioscopy was employed to assess the completeness of valvulotomy and to identify vein wall injury. Incomplete disruption of one or more valve complexes was identified in 2 of 12 (17%) grafts in the Hall group, 10 of 11 (91%) grafts in the LeMaitre group, and 0 of 7 grafts in the Mills group (p < 0.01). Intact valve cusps were noted in 2 of 36 (5.5%) valves, 31 of 42 (74%) valves, and 0 of 38 valves after valvulotomy with the Hall, LeMaitre, and Mills instruments, respectively (p < 0.01). A total of three valvulotome-related injuries occurred; two injuries were noted in conjunction with the Hall instrument, one was associated with the Mills valvulotome, and no injuries were detected after use of the LeMaitre instrument (p = 0.33). These data demonstrated a significantly increased incidence of retained valve cusps when the LeMaitre valvulotome was used. No significant difference in the rate of vein wall injury was noted in the three groups. Thus this study suggests that the LeMaitre instrument is not as effective as either the Hall or Mills valvulotomes for achieving valvular disruption.

Successful management of traumatic false aneurysm of the extracranial vertebral artery by duplex-directed manual occlusion: a case report

A 32-year-old man was transferred to our hospital after a 2.0 by 2.5 cm traumatic false aneurysm of the distal extracranial vertebral artery was noted after a stab wound of the posterior side of the neck. To obviate the need for operative exposure of the distal vertebral artery at the base of the skull, we elected to perform duplex-directed manual occlusion of the lesion. Angiography before and after the procedure, as well as 10-month follow-up duplex ultrasonography, demonstrated satisfactory thrombosis of the false aneurysm without evidence of a residual arterial defect. There was no morbidity associated with the procedure. We conclude that duplex-directed manual occlusion, a new technique recently described for the nonoperative management of postcatheterization femoral false aneurysms, can be applied safely and effectively to false aneurysms in other locations in which the risks and technical difficulties of operative repair render surgery less desirable.

Color-flow duplex-directed manual occlusion of femoral false aneurysms

PURPOSE

During the past 14 months we conducted a prospective clinical trial to evaluate the efficacy of duplex-directed manual occlusion (DDMO) of iatrogenic femoral false aneurysms (FFAs) as an alternative to standard operative management.

METHODS

In all cases DDMO was performed with real-time color-flow imaging while steady, continuous external pressure was applied manually to the neck of the FFA by an experienced vascular technologist for a period of 10 minutes.

RESULTS

Ten of the 11 FFAs treated with DDMO in this series were thrombosed successfully, requiring a mean of 30 minutes of compression per aneurysm (three compressions of 10 minutes each). DDMO was unsuccessful in one patient, whose session was terminated because of severe discomfort as a result of the procedure. All 10 patients with successfully thrombosed FFAs are without recurrence at 1-month follow-up color-flow duplex examination, and there has been no morbidity attributable to DDMO.

CONCLUSIONS

We conclude that DDMO of postcatheterization FFA can be performed safely and is an inexpensive, effective, nonoperative method of managing such lesions. The precise role of this technique would appear to be as a first-line treatment for uncomplicated iatrogenic FFAs.

The ischemic window: a method for the objective quantitation of the training effect in exercise therapy for intermittent claudication

Twenty-two patients with intermittent claudication were prospectively enrolled in a 12-week program of supervised, graded treadmill exercise therapy. Severity and distribution of arterial occlusive disease were ascertained by noninvasive determination of segmental lower extremity blood pressures and waveforms. No attempt was made to modify risk factors for atherosclerotic occlusive disease. The exercise-induced reduction of the ankle pressure and its recovery were recorded over time, and the area under this curve, the "ischemic window," represents the severity of the ischemic deficit. Absolute systolic ankle pressure, ankle-brachial index, maximum walking time, claudication pain time, and the ischemic window were measured before and after exercise training in all subjects. Maximum walking time and claudication pain time increased 659% and 846%, respectively, among the 19 patients completing the 12-week program (p = 0.001; p = 0.0002). These patients underwent a mean reduction of 58.7% in the ischemic window after a standardized workload (p less than 0.05), and this correlated with the degree of symptomatic improvement. Absolute ankle pressure and ankle-brachial index were unchanged after exercise training. This study confirms the utility of supervised exercise therapy in the treatment of intermittent claudication. The ischemic window is a useful method for quantifying the ischemic deficit produced by exercise and provides a reproducible means of documenting functional improvement in patients undergoing exercise training.

Mycotic aneurysm of the suprarenal abdominal aorta

We report on the successful treatment of a patient with a mycotic aneurysm of the suprarenal aorta. The aorta was resected and reconstructed using an in-situ polytetrafluoroethylene graft with a side arm branch to the left renal artery. The use of polytetrafluoroethylene graft for aortic reconstruction after suprarenal mycotic aneurysm resection has not been previously reported. The etiology, bacteriology, diagnosis, and principles of management of mycotic aneurysms of the suprarenal aorta are discussed.

Duplex scanning for the intraoperative assessment of infrainguinal arterial reconstruction: a useful tool?

Duplex scan, arteriography, and graft flow rates were used intraoperatively to assess 56 infrainguinal arterial reconstructions for technical error. Intraoperative duplex scan identified a technical defect or low graft flow velocity in 22 of 56 (39%) grafts. Eleven of the defects were judged to be clinically significant and were corrected. Four of these defects were missed by the completion arteriogram. One technical defect identified by completion arteriography was missed by duplex scan. Fifty percent (5/10) of grafts with an abnormal intraoperative duplex scan which were not corrected occluded within 30 days. Graft flow rates measured by the electromagnetic flowmeter were neither predictive of technical defect nor early graft outcome. Although the sensitivity of arteriography and duplex scan (88% sensitivity for both) were both high for predicting early graft occlusion, the combination of duplex scan and completion arteriography was significantly more accurate (p less than .0001) in predicting early graft outcome than either study alone. Duplex scan identified significant graft defects which were not detected by completion arteriography or graft flow rate measurement. The duplex scan also provided hemodynamic information which was predictive of early graft outcome. The duplex scan can be an important adjunct to completion arteriography for the intraoperative assessment of infrainguinal arterial reconstruction.

Spontaneous carotid dissection: duplex scanning in diagnosis and management

The clinical, duplex, and angiographic findings in six patients with seven spontaneous extracranial carotid artery dissections are reported. Four dissections resulted in internal carotid artery occlusion. These patients complained of ipsilateral headache followed by contralateral hemiplegia. The other three dissections involved the common carotid artery and resulted in dual (one true and one false) lumens. Two of these dissections were asymptomatic. All dissections were treated nonoperatively with anticoagulant therapy. Neurologic deficits improved or disappeared in all symptomatic patients. On follow-up studies, one of the four internal carotid occlusions completely resolved with normalization of the duplex examination. All three dual lumen dissections remained patent on serial studies. Diagnostic duplex characteristics, both conclusive and supportive, of carotid dissections are described. Duplex scanning is shown to be accurate in diagnosing and ideally suited for serially following spontaneous carotid dissections.

The Vena Tech filter: evaluation of a new inferior vena cava interruption device

Expanded indications for caval interruption and earlier diagnosis of deep venous thrombosis have resulted in increased use of transvenous caval interruption devices and have intensified the search for the ideal caval filter. The Vena Tech vena cava filter is a percutaneous, transvenous caval interruption device which was recently introduced in the United States. We reviewed our experience with this filter. During the period of September 1989 to July 1990, 41 patients underwent placement of the Vena Tech filter. Indications for filter insertion included deep venous thrombosis with a contraindication to anticogulation (61%), pulmonary embolism while on anticoagulant therapy (29%), and prophylaxis (10%). Insertion was accomplished percutaneously in 40 patients (98%) and via cutdown in one patient. Thirty-nine (95%) were placed from the right internal jugular vein and two (5%) from the right femoral vein. There were no deaths related to filter placement. Incomplete opening of the filter occurred in 8 patients (19%); however, the incidence of deployment problems decreased as our experience increased. Pulmonary embolism after filter placement occurred in one patient (2%). Duplex scan was obtained postoperatively in 15 patients (mean follow-up 120 days). The inferior vena cava was patent in all patients, although nonoccluding thrombus was identified in the filter in one patient. We conclude the Vena Tech filter is an effective device for caval interruption, is easily inserted, and is associated with minimal morbidity.

Experience with laser-assisted balloon angioplasty and a rotary angioplasty instrument: lessons learned

Favorable early results with mechanical angioplasty devices and laser-assisted balloon angioplasty have resulted in aggressive marketing and a rapid increase in the use of these devices for the treatment of femoropopliteal occlusive disease. Recent reports, however, have questioned the durability of these less invasive procedures. Since 1986 we have been involved in the clinical investigation of the Kensey dynamic angioplasty instrument and laser-assisted balloon angioplasty. One hundred two balloon angioplasty procedures assisted by the Nd:YAG laser (n = 56) and the Kensey dynamic angioplasty instrument (n = 46) were performed for the treatment of femoropopliteal occlusive lesions. Both Kensey dynamic angioplasty instrument and laser-assisted balloon angioplasty groups were similar with regard to age, operative indication, preoperative ankle-brachial index, lesion length, and distal runoff. Mean follow-up was 19 months in the Kensey dynamic angioplasty instrument group and 15 months in the laser-assisted balloon angioplasty group. Technically successful recanalization was achieved in 67% of Kensey dynamic angioplasty instrument-assisted balloon angioplasty procedures and 82% of laser-assisted balloon angioplasty procedures. Early hemodynamic and clinical improvement was obtained in 59% of Kensey dynamic angioplasty instrument-assisted balloon angioplasty procedures and 57% of laser-assisted balloon angioplasty procedures. Two-year clinical success by life-table analysis was 37% in the Kensey dynamic angioplasty instrument group and 19% in the laser-assisted balloon angioplasty group. The level of subsequent surgical revascularization was not altered in any patient by Kensey dynamic angioplasty instrument-assisted balloon angioplasty or laser-assisted balloon angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

Thoracic aortic ectasia in a patient with Takayasu's disease

Arterial aneurysm formation occurs in 15 to 20% of patients with Takayasu's disease. The timing of surgical intervention of these aneurysms is controversial. A case of ectasia of the descending thoracic aorta in a patient with Takayasu's disease is presented. The diagnosis and timing of surgical intervention of aneurysms associated with Takayasu's disease are discussed.

The use of composite grafts in femorocrural bypasses performed for limb salvage: a review of 108 consecutive cases and comparison with 57 in situ saphenous vein bypasses

We retrospectively reviewed the results of 108 consecutive femorocrural bypasses performed with prosthetic/autogenous composite graft material and compared these with the results of 57 crural bypasses using greater saphenous vein by the in situ technique. Indication for operation in all cases was the salvage of an otherwise imminently threatened limb. Polytetrafluoroethylene-composite grafts (n = 87) and human umbilical vein-composite grafts (n = 21) were placed only in patients lacking suitable autogenous material for in-line reconstruction. Patient groups were similar with respect to mean age, prevalence of arterial disease risk factors, quality of the distal runoff, and location of the distal anastomosis. Cumulative patency rates at 1 year by life-table analysis were 81.9%, 34.6%, and 12.1% for the in situ, polytetrafluoroethylene-composite and human umbilical vein-composite groups, respectively. At 2 years these were 63.9%, 29.9%, and 6.0%, respectively (p less than 0.025). Cumulative limb salvage at 1 year was 70.6%, 62.3%, and 32.7%, respectively. Wound-related complications occurred in 52.4% of human umbilical vein-composite, 38.6% of in situ, and 18.3% of polytetrafluoroethylene-composite bypasses (p less than 0.05). On the basis of these results, we conclude that femorocrural bypass with polytetrafluoroethylene-composite graft is an acceptable form of distal reconstruction for limb salvage in patients lacking sufficient lengths of autogenous vein. We no longer use human umbilical vein for composite construction.

Initial results and subsequent outcome of laser thermal-assisted balloon angioplasty of 56 consecutive femoropopliteal lesions

Laser thermal-assisted balloon angioplasty (LABA) was prospectively applied in the treatment of 56 atherosclerotic femoropopliteal occlusive lesions in 51 consecutive patients. All procedures were performed in the operating room using a neodynium:yttrium-aluminum-garnet (Nd:YAG) laser source, and patients were evaluated for immediate and long-term hemodynamic and clinical improvement. Technically successful recanalization was achieved in 82% of cases, with 57% of all patients (32 of 56) obtaining early hemodynamic and clinical improvement. Long-term clinical success (by life-table analysis) was obtained by only 22.5% at 6 months, and only 13.5% at 12 months. Patients presenting with intermittent claudication did significantly better than those presenting for limb salvage (p = 0.01), and trends toward improved outcome were noted for short versus long lesions as well as for patients with "good" versus "poor" distal runoff (NS). Procedure-related morbidity occurred in 14%, and there was one peri-procedural mortality (1.8%). We conclude that the use of LABA is associated with long-term clinical success in only a small proportion of patients, and that widespread clinical application of this technique is not indicated at the present time.

Increased infection rate in double-lumen versus single-lumen Hickman catheters in cancer patients

Over the 48-month period from January 1983 through December 1986, 51 single-lumen (SL) and 94 double-lumen (DL) indwelling central venous (Hickman) catheters were placed in 118 patients with malignant disease. We reviewed these cases retrospectively to determine the types and frequency of complications requiring catheter removal. The catheters were in place a total of 18,397 days. Overall, 14% (7/51) of SL and 21% (20/94) of DL catheters were removed due to infection. Of those catheters becoming infected, DL catheters were infected earlier. SL catheters that became infected averaged 213 days of use before removal, whereas DL catheters becoming infected averaged only 78 days before removal (P less than or equal to .02). The infection rate was significantly less in SL (one infection per 1,210 days) than in DL catheters (one infection per 496 days) (P less than or equal to .02). Thus because of its significantly reduced risk of infection, the single-lumen Hickman may be the preferred catheter for long-term venous access in many patients.

Retroperitoneal approach to aortic surgery

The retroperitoneal approach has been recently advocated as an alternate approach to abdominal aortic surgery rather than the traditional transperitoneal approach. A comparative analysis of these two approaches was undertaken to clarify the differences. From June 1984 through June 1986, 172 patients underwent elective infrarenal abdominal aortic surgery on the Vascular Surgery Service at Eastern Virginia Medical School. One hundred nineteen were operated through a transperitoneal approach, and 53 through a retroperitoneal approach. The two groups were similar relative to age, sex, indications, risk factors and operations performed. The groups were then analyzed relative to operating time, blood transfusion, fluid replacement, ileus, morbidity, length of hospital stay, American Society of Anesthesiologists classification, and mortality. Significant differences were found: retroperitoneal patients had shorter operating time, shorter ileus, fewer cardiac complications, and shorter hospitalization than transperitoneal patients. This retrospective evaluation supports the conclusion that the retroperitoneal approach to abdominal aortic surgery is safe and beneficial in most patients. The retroperitoneal approach should therefore be given consideration in routine aortic surgery.

The Kensey catheter: preliminary results with a transluminal atherectomy tool

The Kensey dynamic angioplasty instrument is an atherectomy device approved by the Food and Drug Administration that uses a rotating cam tip housed within a flexible polyurethane catheter to recanalize obstructed and stenotic arteries. Twenty patients with significant femoral arteriosclerotic occlusive disease underwent attempted transluminal endarterectomy of 23 extremities with the Kensey catheter. Significant improvements of superficial femoral artery luminal diameter was achieved in 10 of 13 patients with stenosis and passage of the spinning catheter tip at 60,000 to 90,000 rpm through areas of complete occlusion was successful in 4 of 10 cases. Balloon dilatation was used as an adjunct to increase the diameter of the superficial femoral artery lumen in 11 of 14 successful cases. This preliminary report provides technical data and short-term follow-up of this new innovative vascular tool.

Evaluation of the expanded polytetrafluoroethylene (EPTFE) suture in peripheral vascular surgery using EPTFE prosthetic vascular grafts

A new suture material, EPTFE, is available for use in vascular anastomoses. This study evaluated the EPTFE suture in 115 procedures on 108 patients, resulting in 198 EPTFE anastomoses. Average length of follow-up was 12.8 months with a range of two to 26 months. No incidence of suture failure resulting in infection, false aneurysm, or anastomotic dehiscence was found. Handling characteristics were found to be favorable. Anastomotic bleeding was minimal in 79%, and excessive in 5%. Available data suggest that physical and biologic characteristics of EPTFE suture are favorable. Long-term clinical follow-up is needed.

Arterialization of reversed autogenous vein grafts: quantitative light and electron microscopy of canine jugular vein grafts harvested and implanted by standard or improved techniques

To provide sequential, quantitative analysis of the cellular events occurring in reversed autogenous vein grafts after implantation and potential modifications of these events, two groups of veins were evaluated. Veins prepared by standard techniques of unmonitored pressure distension with cold heparinized saline solution, tributary ligation adjacent to the wall, and storage at 4 degrees C were morphometrically compared with veins harvested by means of a modified protocol of papaverine irrigation, tributary ligation away from the graft wall, pressure distension to 100 mm Hg with heparinized blood containing papaverine at body temperature, storage in identical solution at 4 degrees C, and implantation while distended. Unilateral jugular veins harvested from dogs with the modified technique (IRJV,N = 9) or standard technique (SRJV,N = 9) were implanted into carotid arteries, retrieved at 30 minutes, 2 days, and 10 days postoperatively along with the contralateral control vein after perfusion fixation in situ, and examined microscopically to quantitate intimal-medial thickness and endothelial damage (denudation and ultrastructural alterations). All IRJVs remained endothelialized, whereas SRJVs had 19% and 40% endothelial denudation at 30 minutes and 2 days, respectively, as well as massive neutrophil, platelet, and monocyte involvement. In contrast, IRJVs had only a modest infiltration of monocytes beginning early after implantation and culminating in their localization beneath endothelial cells; these endothelial cells increased in number during the 10-day period. Although SRJVs exhibited nearly complete reendothelialization over the luminal surface of macrophages by 10 days, endothelial damage was consistently higher than that of IRJVs at all periods and intimal-medial thickness was significantly greater at 10 days (65 +/- 0 vs. 57 +/- 0 micron, respectively; p less than 0.001). These findings suggest that endothelial preservation with improved harvesting techniques inhibits thrombosis and limits wall thickening and also that macrophages may play a protective role by promoting endothelial proliferation.

Freshly harvested cadaveric venous homografts as arterial conduits in infected fields

Six patients with patent multilevel prosthetic grafts (three axillofemoral-femoral grafts, an aortobifemoral graft, an axillofemoral and femoral-anterior tibial graft, and an axillofemoral and femoral-popliteal graft) that demonstrated overt infection involving both the proximal inflow (one infrarenal aorta, five axillary arteries) and groin anastomoses required complete graft excision. Cadaveric inferior vena cava, common and external iliac, common and superficial femoral, and greater saphenous veins were harvested in conjunction with multiple organ donor procedures. Identical anatomic reconstruction within the infected fields was accomplished, with patency and distal perfusion maintained for intervals sufficient to achieve complete resolution of infection in all cases. This interval of revascularization with a venous homograft has served as a temporizing maneuver, which permitted eradication of infection and allowed subsequent reimplantation of prosthetic graft material without associated reinfection in the two instances in which it was required. Use of freshly harvested large-caliber caval, iliac, and femoral homograft veins as arterial substitutes in infected fields has not been previously reported. Case histories and a review of the venous homografting literature are included.

The mangled extremity syndrome (M.E.S.): a severity grading system for multisystem injury of the extremity

The severely mangled extremity presents a challenge in appropriate surgical management. Very few objective data were found about this problem. To clarify the situation, criteria for a "mangled extremity' were defined, a multidisciplined approach employed, and a retrospective graduated grading system developed. Sixty consecutive trauma patients with severely injured extremities during the past 3 years were reviewed. Seventeen patients fit the category of Mangled Extremity Syndrome (M.E.S.). Injuries were retrospectively classified using a graduated grading system directed at four major tissue systems of the extremity involved (integument, nerve, artery, and bone). Additional scoring items were included to define the significance of trauma sustained outside the extremities. Patients who ultimately came to amputation could have been identified preoperatively at initial emergency evaluation utilizing this graduated grading system. Retrospective data suggest that a Mangled Extremity Syndrome Index (M.E.S.I.) of 20 is the dividing line below which functional limb salvage can be expected and above which limb salvage is improbable. Prospective application of this system, as well as an organized multidisciplined approach, could be useful in the identification of functionally retrievable versus probably irretrievable extremities, thus identifying and helping define the indications for amputation. The grading system criteria and results in these 17 patients form the basis of this report.

Failure of arteriovenous fistulas at distal tibial bypass anastomotic sites

Arteriovenous fistula formation has been advocated to increase the outflow for tibial and peroneal distal bypass grafts. Between January, 1981 and September, 1981, twenty-seven patients underwent thirty femoral to distal tibial or peroneal artery bypass procedures with creation of an arteriovenous fistula at the site of the distal anastomosis. Limb salvage was the primary indication for surgery in 97% of this severely ischemic group, with a mean ankle pressure index of 0.32. Despite high flow rates averaging 260 cc/minute and an initial patency rate of 97%, there were only two fistulas patent in intact limbs at the conclusion of the initial eight month follow-up period with one additional occlusion at 16 months. Limb salvage to the present (July 1983) was achieved in only six cases. In the patients with limb salvage, three bypass grafts remain patent despite fistula occlusion, two patients have occlusion of both graft and fistula but no rest pain, and a single patient has maintained both graft and fistula patency for 23 months. Creation of an arteriovenous fistula at the distal anastomotic site of tibial bypass procedures augments graft flow in the immediate post-op period; but, has very low long term patency rates and is not beneficial to graft patency or effectiveness.

Optimal techniques for harvesting and preparation of reversed autogenous vein grafts for use as arterial substitutes: a review

Since the first successful use of an autogenous vein graft for arterial reconstruction by Gluck in 1898 and the establishment of the scientific basis for the use of veins as arterial substitutes by Carrell and Guthrie in the early 1900s, reversed autogenous veins have been used extensively in arterial reconstructive operations. Despite being the preferred material for reconstruction, reversed autogenous vein is not an ideal graft material. The primary problem is structural alterations in the implanted vein predisposing to graft failure. Most of these failures occur within the first few months after graft implantation and are though to be due, in part, to endothelial damage incurred during harvesting and preparation of the vein. This review focuses on technical aspects of vein graft harvesting associated with alterations in endothelial morphology including dissection technique, types of irrigation and storage solutions used, temperature of these solutions, distension pressures, and pharmacologic agents. An optimal technique incorporating subcutaneous and perivenous infiltration with papaverine, atraumatic dissection, controlled gradual distension, and storage of the distended vein in cold heparinized blood containing papaverine should produce grafts with improved endothelial preservation and patency rates compared with grafts harvested by techniques in widespread use at present. The importance of morphologically and functionally intact endothelium in reversed vein grafts, a comparison to that produced by in situ vein grafting, and its possible clinical implications are discussed.

Carotid involvement in aortic dissection diagnosed by duplex scanning

Symptomatic carotid dissection following repair of a proximal aortic arch dissection has been successfully diagnosed by noninvasive ultrasonic duplex scanning. Angiographic confirmation, follow-up examinations by duplex scanner, and conservative management with heparin anticoagulation and tight blood pressure control are discussed. The differing etiologies and potential neurologic complications following aortic root dissection vs. spontaneous cervical carotid dissection are considered with a review of the current literature. Although diagnosis can be achieved through arteriography, the combined modalities of duplex scanning allow evaluation of both anatomic and hemodynamic factors. Conservative therapy may prove the most appropriate mode of management in these neurologically unstable patients.

Autogenous graft replacement of infected prosthetic grafts in the femoral position

Infected prosthetic grafts in the femoral position remain among the most challenging problems in vascular surgery. Over the past 2 years, 11 patients with this critical condition have undergone graft reconstruction with autogenous tissue as described by Ehrenfeld. All infected prosthetic material was removed and replaced by an autogenous graft. The autogenous grafts were constructed with endarterectomized superficial femoral, iliac, and aortic segments as well as portions of saphenous and cephalic veins. This procedure has proven successful, resulting in only one amputation (undertaken with a still functioning autogenous graft) in the series. There was one postoperative death. Six grafts failed in long-term follow-up, due in all cases to inadequate flow because of stenosis of the saphenous vein portion of the autogenous reconstruction. However, the patients were usually free of infection by this time and underwent successful prosthetic reconstruction.

Composite grafts: an alternative to saphenous vein for lower extremity arterial reconstruction

In the absence of adequate saphenous vein for femoral-popliteal/infrapopliteal bypass grafts, composite grafts constructed with PTFE (Gore-tex) and short segments of autogenous tissue were utilized. The composite grafts (208 cases) were compared to plain PTFE (Gore-tex) grafts (235 cases) and to the literature results reported for saphenous vein grafts (2,108 cases) in limb salvage situations. Evaluation using life table analysis with followup extending to 63 months indicates composite grafts yielded favorable results when compared to the "gold standard" of saphenous vein and superior results to plain PTFE (Gore-tex) grafts for infrapopliteal bypass. A combined, dual center approach was chosen to enhance significance by expanding the number of patients evaluated and extending the period of followup from earlier studies reported separately from each center.

Axillofemoral bypass: a ten-year review

During a ten-year period (1969-1980), 106 grafts were implanted in the axillofemoral and axillobifemoral positions. This retrospective study is based on life table analysis of cumulative patency rates in both axillofemoral and axillobifemoral grafts, with and without thrombectomy. Dacron grafts were used exclusively from 1969 to 1979, and PTFE from 1979 to 1980. Cumulative patency for Dacron axillobifemoral grafts was 97 +/- 3% at 32 months (73 +/- 21% at 42 months). Patency in both unilateral and bifemoral grafts was significantly increased by thrombectomy. Dacron and PTFE axillobifemoral graft patency was not significantly different. Perioperative mortality was 8% in a group of patients whose survival rate at four years was only 50 +/- 10% from associated disease. Axillobifemoral grafting presents an alternative to aortoiliac reconstruction in elderly patients with severe associated disease in whom the risk of anatomic bypass is prohibitive.

Primary tumors of the aorta: report of a case and review of the literature

A patient with an unusual vascular tumor, an angiosarcoma of the upper abdominal aorta, is described. The clinical, radiologic and pathologic features of this case along with 19 previously reported cases of primary aortic tumor are discussed. Primary aortic neoplasms are uncommon. They are histologically and morphologically diverse tumors in which major vascular obstruction and arterial tumor embolization dominates the clinical picture. At present, aortography combined with computerized tomography offer the best means of preoperative diagnosis.

Chemoneurolysis of the canine gastric submucosa. Effects on surgically-induced gastric hypersecretion on the Heidenhain pouch

Double denervated gastric pouches were constructed in dogs. One gastric pouch served as a control, and the other gastric pouch had its submucosa infiltrated with 25% ethyl alcohol, (submucosal chemoneurolysis). Neurolysis of these gastric pouches eliminated their gastric secretory responses to histamine, meat and pentagastrin without altering their histological appearance. Transplantation of 75% of the gastric antrum into the colon caused a hypergastrinemia and increased the sensitivity of the control gastric pouches to the various stimuli but had no such effect on those gastric pouches infiltrated with ethyl alcohol.

Chemoneurolysis of the canine gastric submucosa. Effects on Heidenhain pouch secretion

Double denervated gastric pouches were constructed in dogs. One gastric pouch served as a control, and the other gastric pouch had its submucosa infiltrated with 25% ethyl alcohol (submucosal chemoneurolysis). Neurolysis of these gastric pouches did not alter their histological appearance but did eliminate their gastric secretory responses to histamine, meat and pentagastrin. The dogs exhibited elevated serum gastrin levels after feeding.