Internal carotid artery aneurysm. A case report.

This case report documents the diagnosis and treatment of a large carotid artery aneurysm (4 cm) associated with fibromuscular hyperplasia of the internal carotid artery. This patient underwent replacement of the section of internal carotid artery using a segment of the proximal greater saphenous (from the groin to upper thigh). She did well postoperatively with the exception of some difficulty with swallowing, which rapidly cleared. At one year she was neurologically intact with no complaints.

Femoral deep vein thrombosis associated with central venous catheterization: results from a prospective, randomized trial.

OBJECTIVE: To determine the frequency of central venous catheter-induced deep vein thrombosis of the femoral vein. DESIGN: Prospective, randomized, controlled trial. SETTING: Tertiary care center. PATIENTS: Forty-five patients in a medical-surgical intensive care unit who required central venous catheterization. INTERVENTIONS: Patients were randomized to receive central venous catheterization in either upper (subclavian or internal jugular veins) or lower (femoral vein) catheterization sites. Lower extremity duplex ultrasound examinations were performed before central venous catheter placement, after removal of the catheter, and 7 days after catheter removal. Ultrasound examinations were reported as positive, nondiagnostic, or negative for deep vein thrombosis. MEASUREMENTS AND MAIN RESULTS: Of the 21 patients randomized to upper access sites, none developed positive or nondiagnostic duplex ultrasound examinations. Six (25%) of 24 patients randomized to the femoral access site developed lower extremity deep vein thrombosis (p = .02). In addition, seven (29%) patients randomized to the lower access site sustained non-diagnostic ultrasound examinations. A total of 13 (54%) of 24 patients from the lower access group developed abnormal ultrasound examinations (p < .001). Age, duration of catheterization, coagulation profile, deep vein thrombosis prophylaxis, and Acute Physiology and Chronic Health Evaluation II scores were similar between the upper and lower access groups. CONCLUSIONS: Based on the data from this study, we concluded that femoral vein catheterization is associated with a 25% frequency of lower extremity deep vein thrombosis compared with similar patients receiving subclavian or internal jugular vein catheters. The femoral vein remains an important emergency venous access route. Physicians inserting femoral vein catheters should be aware of the risk of lower extremity deep vein thrombosis and should consider performing lower extremity duplex ultrasound examinations on removal of femoral vein catheters.

Penetration of the wall of an abdominal aortic aneurysm by a Greenfield filter prong: a late complication.

This is a case report of a 68-year-old woman in whom a late and previously unreported complication developed that resulted from penetration of an aortic aneurysm by the prong of a stainless steel Greenfield filter. This complication came into view 7 years after placement of the filter, at the time of aneurysm resection. Enlargement of the aneurysm had occurred at a rapid rate. The patient was symptom free before surgery.

Value of lower extremity venous duplex examination in the diagnosis of pulmonary embolism.

PURPOSE: This study tests the hypothesis that the absence of deep venous thrombosis (DVT) on lower extremity color-flow venous duplex examination (LECFD) combined with a non-high-probability ventilation/perfusion (V/Q) scanning results rules out pulmonary embolus (PE). The use of LECFD as a diagnostic aid for PE is based on data that show that 90% of PE originate from lower extremity DVT, and therefore on the assumption that PE cannot be present if DVT is not present as the source. METHODS: Over a 3-year period 51 patients with clinically suspected PE underwent LECFD and pulmonary angiography (PA) within 72 hours of each other. Forty-one patients also underwent V/Q scanning during the same time period. The results of LECFD and V/Q scans were compared with the results of PA, the gold standard for the diagnosis of pulmonary emboli. RESULTS: Results of LECFD were positive for DVT in seven of 16 cases of angiographically documented PE. Thus the "sensitivity" of LECFD as a diagnostic aid in cases of suspected PE is 44%. The results of LECFD and V/Q scans were combined and compared with the results of PA. A high-probability V/Q scanning result was considered positive for PE. Intermediate- and low-probability scanning results were considered negative, because in the literature the decision to begin heparin therapy is not made on the basis of this result. The combination of test results was considered positive if either test result was positive and negative only if results of both were negative. With these criteria the combination of test results was positive in only 62% of cases of angiographically documented PE. CONCLUSIONS: If treatment of suspected PE were based on LECFD alone or on duplex combined with V/Q scanning, 40% to 50% of patients with PE would remain untreated. In cases of suspected PE where these noninvasive tests do not confirm its presence, PA should be performed.

Asymptomatic severe carotid stenosis.

The management of asymptomatic carotid stenosis remains controversial. From December 1983 to December 1987, 188 symptom-free patients were found to have severe (greater than 75%) stenosis by duplex imaging (performed as screening examination). Patients with non-hemispheric symptoms or contralateral symptomatic lesions (within 7 years) were excluded from the study. Follow-up data were available for 141 patients (range 3 to 36 months; mean 21 months). Sixty-two patients received nonoperative therapy. The remaining 79 patients underwent 100 carotid endarterectomies (CAE) (21 staged bilateral repairs and 58 unilateral repairs). There were no statistically significant differences in sex, age, or risk factors (i.e., hypertension, diabetes, or smoking) or in the incidence of bilateral disease. Significant differences were found in the incidence of ischemic attacks (0 vs 21%; p less than 0.001) and stroke (2.5% vs 18%; p less than 0.01) in the operative vs nonoperative group. None of the 11 strokes in the nonoperative group were preceded by neurologic events. The operative group had an overall stroke rate of 2.5% (2/79), a perioperative mortality rate of 1.3% (1/79), and a restenosis (greater than 50%) rate of 3.8% (3/79). Thus favorable results can be achieved with prophylactic CAE. These data support the use of prophylactic CAE in any patient with greater than 75% stenosis identified by duplex image, regardless of sex, age, risk factors, or bilateral disease.

Noninvasive imaging for deep venous thrombosis.

In 96 patients, 127 extremities were identified by duplex ultrasonography as having acute deep venous thrombosis. The majority of these patients were found to have factors that predisposed them to thrombi formation. Doppler examination correlated with the duplex results in 77 extremities (61 percent). Two factors were identified that led to discrepancies between the results of these two modalities: (1) Thrombi that were more proximally located and totally occlusive were more likely to result in abnormal Doppler results than those that were not. (2) Doppler examination of the deep venous system of the lower extremities, although more accurate than clinical evaluation, was of insufficient accuracy to make correct decisions regarding the need for anticoagulation.

The use of deep duplex scanning to predict hemodynamically significant aortoiliac stenoses.

Hemodynamic assessment of aortoiliac occlusive disease is necessary for successful arterial reconstruction of the aorta and legs. Various methods have been proposed and "pull-through" intra-arterial pressures are the "gold standard." Deep Doppler duplex imaging was supplemented with real-time spectral analysis and velocity measurements in 29 cases. Twenty-three of these patients needed arteriography. One hundred sixty-six (166) arterial segments extending from the proximal aorta to the common femoral arteries were independently graded on duplex scans and arteriograms. For severe occlusive disease, duplex scanning is highly accurate (sensitivity 82%, specificity 93%). Velocity measurements were useful in determining the hemodynamic significance of stenoses. Peak systolic velocities in stenoses were measured with a duplex scanner. The pressure gradient calculated with the modified Bernoulli equation (delta P = 4Vmax2) correlated well with the gradients measured during arteriography (r = 0.9, n = 11). These noninvasive velocity measurements and Bernoulli calculations alert arteriographers to obtain special views of suspected areas and suggest the need for "pull-through" pressures and possible balloon angioplasty. In addition, these noninvasive measurements are useful to follow up patients who have mild to moderate aortoiliac disease and after angioplasty.

Distal arterial reconstruction: patency and limb salvage in diabetics.

Controversy regarding efficacy and durability of distal bypass grafting of the diabetic patient exists. A 22-year-long series of 259 vascular procedures with 100% follow-up (57% in diabetic individuals) is examined to compare these results with those of non-diabetic patients. Extensive review of predisposing factors, operative indications, preoperative medical evaluation, as well as techniques and peculiarities of angiography is rendered. Peripheral arterial case mix between the two groups is examined. The high utilization rate of solely venous conduits (94%) in diabetics compared with 76% in nondiabetics, along with anastomosis site selection, provides the most reasonable explanation for the successful outcome in both groups. Modifications in revascularization techniques contributing to successful outcome are presented. In the diabetic patients, both the cumulative graft patency rate (63%) and the limb salvage rate (77%) at 6 years were superior to those of the non-diabetics (52% and 65%, respectively). Diabetes mellitus does not predispose the person requiring revascularization for limb salvage to a lesser likelihood of success.

Duplex B-mode imaging for the diagnosis of deep venous thrombosis.

Real-time B-mode venous imaging has numerous advantages for the diagnosis of acute deep venous thrombosis (DVT). During the 11 months ending Feb 1, 1986, we examined 431 patients for possible acute DVT using a 5-MHz hand-held continuous wave Doppler stethoscope and a duplex real-time B-mode imager. Clots were seen in 86 patients in multiple views and cross sections. Normal veins completely collapsed with probe pressure on the skin. Blood flow was seen and heard, and abnormal flow was detected. There were no false-negatives (100% sensitivity). Early in the study, two false-positives occurred (78% specificity), but these errors will not recur. These tests are accurate, noninvasive, and inexpensive. They differentiate acute from chronic thrombosis and are repeatable. Duplex imaging may become the "gold standard" for the diagnosis of DVT.

Comparison of initial limb salvage in 98 consecutive patients with either reversed autogenous or in situ vein bypass graft procedures.

A retrospective review of 98 consecutive patients undergoing femoropopliteal or distal bypass procedures was conducted to determine whether in situ bypass grafting offers statistically significant initial limb salvage over reversed autogenous techniques. Over a 40 month period, 98 consecutive patients received either in situ or reversed autogenous vein grafts to effect limb salvage. The groups were similar in incidences of diabetes and previous myocardial infarctions, as well as in site of distal anastomosis (beneath the tibial peroneal trunk in more than 80 percent). The in situ vein graft group had an overall limb salvage rate of 92 percent with an 88 percent cumulative patency rate at 4 to 18 month follow-up, whereas the reversed autogenous vein graft group had a limb salvage rate of 86 percent with a 79 percent cumulative patency rate at up to 18 months. Results after 30 days showed 47 patients had improvement and 3 patients (6 percent) had died in the in situ vein graft group. In the reversed autogenous vein graft group, 44 patients improved, 4 did not improve and required amputations, and 2 (1 percent) died. Our study supports the use of in situ vein bypass grafting for limb salvage.

Surgical implications of fibrinolytic therapy.

Intraarterial fibrinolytic therapy was used in 37 cases (34 patients) of severe peripheral ischemia. Nineteen patients (56 percent) required surgical intervention (5 amputations and 14 successful reconstructive procedures). Twenty-four patients (71 percent) were significantly improved (average ankle-to-arm index 0.84), whereas only 5 patients (15 percent) lost their limbs. Five patients were angiographically unchanged with no or slight improvement in the ankle-to-arm index (0.22 to 0.32) and were discharged on anticoagulant therapy. One death and two cerebrovascular accidents occurred. The usefulness of intraarterial fibrinolytic therapy needs to be evaluated within the total realm of vascular surgery. It offers options for therapy where previously none existed. Some situations might be treated equally well with either intraarterial fibrinolytic therapy or surgery. Finally, surgery might be required to maintain initial successful results with intraarterial fibrinolytic therapy or to rescue intraarterial fibrinolytic therapy failures in striving to achieve superior results in limb salvage.

Distal tibial vein grafts for limb salvage.

Bypasses below the tibial peroneal trunk, which are not commonly performed, are an effective method of limb salvage. We have done long-term follow-up of all 148 consecutive grafts done during the past 19 years. By careful patient selection, detailed arteriograms, utilization of veins from all extremities, meticulous operating technique, and noninvasive follow-up, we have achieved a limb salvage rate of 75% and a cumulative five-year patency rate of 62%. Diabetics made up 53% of the series and did not affect the results. Seventy-one percent of all failures occurred in the first six months. Considering the charges for hospitalization, amputation, prostheses, and rehabilitation, distal tibial bypass procedures are cost-effective.