Mechanisms in experimental venous valve failure and their modification by Daflon 500 mg.

OBJECTIVES: To characterize the acute response of the vein wall to venous hypertension and associated altered fluid shear stress and to test the effect of micronized purified flavonoid fraction (MPFF, Daflon 500), on this response. MATERIAL AND METHODS: A femoral arteriovenous fistula was created in Wistar rats (n=48). A cohort of 24 rats received oral treatment with MPFF (100 mg/kg/day body weight), 24 rats underwent the arteriovenous fistula procedure and received no treatment. At days 1, 7 and 21 the animals (n=8 at each time point) were killed. Experimental parameters measured included limb circumference, blood flow at the sapheno-femoral junction, leukocyte infiltration and gelatinase activity (matrix metalloproteinase, MMP). RESULTS: The acute rise in venous hypertension was accompanied by limb edema and venous reflux together with an eventual loss of valve leaflets in the saphenous vein. There was an increase in granulocyte and macrophage infiltration into the venous wall and the surrounding tissue, and a lesser increase in T- and B-lymphocyte infiltration. These changes were accompanied by a local increase in the proteolytic enzymes, MMP-2 and MMP-9. Administration of MPFF reduced the edema and lessened the venous reflux produced by the acute arteriovenous fistula. Decreased levels of granulocyte and macrophage infiltration into the valves were also observed compared with untreated animals. CONCLUSIONS: Venous hypertension caused by an arteriovenous fistula resulted in the development of venous reflux and an inflammatory reaction in venous valves culminating in their destruction. MPFF was able to delay the development of reflux and suppress damage to the valve structures in this rat model of venous hypertension.

New clinical and laboratory staging systems to improve management of chronic lymphedema.

We have developed new clinical (C) and laboratory (L) staging systems to improve the clinical management of chronic lymphedema. These systems were retrospectively assessed in 220 chronic lymphedema patients followed up for 4 years. Clinical evaluation of the treatment response/disease progression was performed at 6 month intervals and laboratory evaluation at a yearly interval except for recurrent sepsis cases. The reliability of C-stage and L-stage for the progression of disease were analyzed separately. The C-staging was based on the subjective and objective findings of local and systemic conditions, while L-staging was based on lymphoscintigraphicfindings. Clinical implementation of this new staging system facilitated interpretation of the progress/deterioration of the clinical response to CDT treatment, and it was found to be a useful guideline for the decision/selection of further surgical treatment. We propose that these two separate staging systems could now become a new guideline for improved management of lymphedema with a better prediction of treatment outcome and decision point for additional medical/surgical therapy. Further clinical implementation and evaluation is necessary to demonstrate clinical usefulness especially to guide surgical therapy and L-staging in followup.

Donor HL-A incompatibility and lymphocytotoxic antibody response in human renal allotransplantation.

When 81 recipients of primary renal allografts were examined for the influence of donor HL-A incompatibilities (DIC) on the survival of allografts, an association was found between greater DIC and not only an increased loss of allografts in the 1st year, but also a decreased survival of transplants in the subsequent years. However, three allografts with no DIC were rejected, whereas nine others with three to four imcompatibilities have functioned well for 1-5 years. A surprisingly high proportion (52%) of 81 renal allograft recipients produced lymphocytotoxic antibodies which lack HL-A specificity but apparently detect a polymorphic antigenic system on normal human lymphocytes. Only three patients who rejected the allografts made detectable circulating antibodies specific to DIC. However, when patients received grafts with fewer DIC, there was a greater number of no antibody or low frequency antibody producers, whereas with a greater number of DIC there was an increased occurrence of high frequency antibody producers. These results suggest that HL-A as well as non-HL-A systems may play a significant role in the success of allotransplantation. Although the presence of non-HL-A antibodies was not always associated with allograft loss, further characterization of these antibodies may reveal a new genetic system(s).

Abdominal aortic salmonellosis.

A recent example of Salmonella mycotic abdominal aortic aneurysm is presented together with a review of the 24 other cases in the literature. Emphasis is placed on common modes of presentation, diagnosis, and surgical management. A review of current theories of etiology is presented along with a new, more descriptive classification of mycotic aneurysms.

Use of the axillary artery in complex cerebral revascularization.

Two cases of complex common carotid and innominate artery disease managed by axillocarotid autogenous saphenous vein bypass are presented, including a detailed description of the operative technique. The results in each case were gratifying. Although the concept of extra-anatomic repair is not new, this modification in operative technique expands the surgeon's armamentarium. The ease and safety of exposure and anastomosis of the axillary artery combine to make it the preferable donor vessel for extra-anatomic cerebral revascularization in the poor-risk, elderly patient population.

Correlation of immune and nutritional status with wound complications in patients undergoing vascular operations.

The acquired failure of host immunocompetence that may result from significant protein and caloric malnutrition has been associated with an increased incidence of septic complications in patients undergoing operation. Wound infection in patients undergoing vascular surgical procedures may lead to exposure or contamination of a vascular graft, with the subsequent risk of hemorrhage, limb loss, or death. The present study was undertaken to correlate the immune and nutritional status of patients undergoing vascular surgical procedures with the development of significant wound complications. Seventy-nine patients undergoing a variety of vascular operations were subjected to comprehensive nutritional assessment, including anthropometric measurements (height, weight, midarm circumference, triceps skin fold), serologic testing (albumin, transferrin, lymphocyte count, serum zinc), cutaneous assessment of delayed hypersensitivity (anergy battery), and neutrophil functional analysis. After operation the patients were observed for the development of delayed wound healing or wound infection. Statistical analysis of measured variables was performed to identify immune and nutritional markers with prognostic value. Patients with serum albumin levels above 3 gm/dl were much more likely to have uncomplicated wound healing (P less than 0.001). Similarly, patients with serum transferrin levels above 150 mg/dl had significantly fewer wound problems (P less than 0.01). Only 29% of patients with cutaneous anergy had normal wound healing, while 56% of those with intact cutaneous reactivity healed primarily; this difference, however, was not statistically significant. Diabetics in this series were more likely to develop wound problems (P less than 0.05). Anthropometric measurements provided no predictive information regarding the likelihood of uncomplicated healing. Similarly, measurement of total lymphocyte count and serum zinc yielded no significant prognostic information. The urgent nature of many vascular surgical procedures may preclude preoperative immune and nutritional assessment; however, the outcome of these procedures may ultimately depend upon intact host defense. The contribution of protein and caloric malnutrition to immunocompromise can be easily assessed in these patients. The detection and subsequent reversal of immunoincompetence through the use of enteral or parenteral alimentation should provide a significant reduction in operative morbidity and mortality.

Ankle pressure changes in distal bypass grafts during knee flexion.

Systolic ankle blood pressure was measured with the limb extended and then acutely flexed in four study groups. These included 11 normal individuals, 11 patients with below-knee autologous saphenous vein bypass grafts, 11 patients with polytetrafluoroethylene (PTFE) prosthetic below-knee bypass grafts, and 11 patients with femoropopliteal arterial occclusion who had not undergone bypass grafting. This study shows that normal limbs, limbs with saphenous vein bypass grafts, arteriosclerotic limbs, and those with PTFE bypass grafts all tolerate acute knee flexion without significant decrease in distal blood pressure.

Sequential femoral-tibial bypass for severe limb ischemia.

Sequential femoral-popliteal-tibial bypass has been recommended for surgical treatment of severe lower limb ischemia in patients with complex multisegmental arterial occlusion. To evaluate this alternative technique critically, sequential grafting was performed in 40 limbs with severe ischemia manifest by rest pain (20), nonhealing ulceration (eight), or gangrene (12). Measurement of segmental Doppler arterial pressure revealed a significant increase in ankle brachial index from 0.29 +/- 0.15 before operation to 0.93 +/- 0.12 after operation, confirming the hemodynamic improvement among these patients. In the early postoperative period occlusion of the distal graft segment was recognized in 12 patients by a characteristic reduction of the ankle/brachial index (0.50 +/- 0.14), while the low thigh pressures remained unchanged. Recurrent severe ischemia was prevented in most by persistent patency of the proximal graft segment. Overall, significant hemodynamic improvement was achieved in 29 of 38 limbs, a limb salvage rate (76%) comparable to that reported for femoral-distal bypass or femoral-popliteal bypass to an isolated popliteal segment. Early graft failure in this series resulted in major amputation in eight of 16 limbs, a significantly lower rate than for these other techniques. Sequential bypass grafting is a useful alternative method for limb salvage. The preservation of the proximal graft patency after distal segmental occlusion may be an important characteristic of this type of reconstruction.

Assessment of donor limb hemodynamics in femorofemoral bypass for claudication.

During a 5-year period (1975 to 1980), 44 patients underwent femorofemoral bypass for unilateral disabling claudication caused by iliac atheroocclusive disease. All patients had complete Doppler arterial examination performed pre- and postoperatively, including segmental thigh and ankle pressure and calculation of an ankle/brachial (A/B) index for each limb. In 37 patients, standard treadmill exercise testing was performed before and after femorofemoral grafting. Hemodynamic improvement in the symptomatic limb was evidenced by an increase in resting A/B index from a mean of 0.54 +/- 0.14 before to 0.76 +/- 0.22 after operation (P less than 0.001). Exercise tests which were abnormal in all 37 recipient limbs preoperatively were improved. Six of the seven unimproved recipient limbs had associated femoropopliteal occlusion. Donor limb mean resting ankle/brachial index fell from 0.93 +/- 0.22 before to 0.83 +/- 0.22 after surgery (P less than 0.05). However, in 13 of 23 donor limbs, exercise response which had been normal before surgery became abnormal. Additionally, in 14 patients with abnormal donor limb exercise response before grafting, seven limbs had a significantly worsening of the exercise response postoperatively. These findings were not related to the patency of the superficial femoral artery in the donor limb. Deterioration in donor limb hemodynamics noted in 20 (45%) of the 44 patients in this series suggests that strict patient selection criteria should be maintained. Unlike in healthy subjects, an arteriographically patent atherosclerosis iliac artery may not support flow requirements of bilateral lower limb exercise.

Lymphatic disruption in varicose vein surgery.

In order to investigate the possibility of lymphatic disruption occurring during varicose vein surgery, lymphangiography performed by a modification of the Kinmonth technique was done in seven patients before and after standard surgical ablation of primary varicose veins. All seven patients demonstrated marked disruption of lymphatics. Extravasation of lymphangiogram contrast medium at the calf level and at the thigh level precluded demonstration of the groin lymphatics. It is concluded that lymphatic disruption attends varicose vein removal and such lymphatic damage contributes to postoperative leg edema.

A systematic approach to severe hand ischemia.

Because severely symptomatic hand ischemia is not common and because there are a wide variety of clinical conditions which can cause arterial insufficiency of the upper extremity, a retrospective study has been done to determine the efficacy of various diagnostic manipulations used in managing 65 patients with severe hand ischemia at the Northwestern University McGaw Medical Center, Traumatic, thermal, and iatrogenic causes of hand ischemia were diagnosed by simple history taking, as was advanced uremic arteritis. Doppler ultrasound and digital arterial pressure recording were confirmative, rather than diagnostic. These aided in defining precise degrees of ischemia and identifying proximal arterial occlusions. Invasive total extremity angiography clarified atherosclerotic, atheroembolic, and other chronic occlusive lesions while serum electrophoresis and immunoelectrophoresis defined the polyclonal and monoclonal gammopathies. When digital necrosis was present, organic arterial occlusions usually were found. These responded best to direct arterial reconstruction down to the mid-palm level. Transpleural, transthoracic sympathectomy was useful as an adjuvant or as definitive treatment for distal digital arterial occlusions. Selective vasodilator therapy was used as dictated by the cause of ischemia and its eventual outcome.

Correlation of foot arterial anatomy with early tibial bypass patency.

The detailed arterial anatomy of the foot in severe limb ischemia is not well known. This study was undertaken to define foot arterial anatomy and correlate these findings with the early results (6 months) of femoral-distal bypass. After completion of the bypass, operative arteriography was performed by direct injection of contrast media into the graft. A lateral view of the distal limb and foot was obtained. Foot vessel anatomy was classified into primary and secondary pedal arches, analogous to the superficial and deep volar arches of the hand. For peroneal bypass, special attention was paid to perforating branches and their communications with these two pedal arches. A total of 56 distal bypass operations was analyzed. Femoral--anterior tibial bypass was performed in 26 cases. When either a primary or a secondary pedal arch was intact, early graft patency (6 months) was achieved in 20 of 21 patients. When neither pathway was present, graft failure occurred in four of five cases. Similarly, of 10 femoral--posterior tibial grafts, seven remained patent with at least one pedal arch intact, whereas six of seven grafts failed when neither arch was patent. Bypass to the peroneal artery was successful in eight of nine limbs when a patent primary or secondary arch was reconstituted via either the anterior or posterior perforating branches. None of four peroneal grafts remained patent when both arches were occluded. As a whole, in 40 limbs with either a patent primary or secondary pedal arch, early graft success was achieved in 35 limbs (87.5%). In contrast, in 16 limbs with no patent arch, only two (12.5%) were successfully reconstructed (P less than 0.001). Analysis of the results of femoral-distal bypass based on a single plantar arch as the sole determining anatomic factor in graft patency is not adequate. The secondary pedal arch and communicating branches of the peroneal artery are also of surgical significance. Operative arteriography can define runoff in the foot, and this information has prognostic significance. It may allow rational judgment regarding reintervention in patients with failed grafts.

Management of infection of major amputation stumps after failed femorodistal grafts.

A retrospective review was performed of 174 patients who underwent 199 lower-extremity amputations for unreconstructable vascular insufficiency from 1976 to 1983 at the Northwestern University Medical Center. This study was initiated to identify the cause of amputation wound healing complications and secondary ascending prosthetic graft infection, as well as to propose a plan of management for the failed prosthetic grafts at the time of major limb amputation. Ninety-eight amputations were performed primarily, 12 were performed secondary to graft infection, and 89 were performed in patients who had previously undergone infrainguinal arterial bypass procedures. At the time of amputation, graft management consisted of high transection and suture ligation, allowing the graft to retract into the substance of the stump and away from the skin suture line and weight-bearing area of the limb. Delayed stump healing was noted to occur more commonly in the group who had undergone previous bypasses as opposed to those who had undergone primary amputation (34.8% versus 14.3%). Fourteen graft infections developed in 89 patients after amputation (15.7%), which is significantly higher than the overall 1.4% incidence of lower-extremity bypass infections that occurred during the same interval in patients with intact extremities. In addition, it was found that when infected grafts in amputated limbs were completely removed, stump healing without recurrent wound and graft sepsis was better than when treated locally or with partial graft removal. We therefore recommend removal of a thrombosed graft with an infected wound or an infected graft at the time of major limb amputation to decrease the incidence of wound complications and graft infection.

Use of a temporary shunt for renal transplant protection during aortic aneurysm repair.

Broader indications for renal transplantation and improved allograft survival suggest that aortic aneurysms will be encountered more commonly in kidney transplant recipients. This report describes the use of a temporary heparin-bonded shunt placed from the proximal abdominal aorta to the femoral artery for perfusion of a renal allograft during simultaneous repair of an aortic aneurysm and correction of transplant renal artery stenosis. Renal function was satisfactorily maintained intraoperatively and has continued to be excellent during 2 1/2 years of follow-up. Methods of renal transplant protection during aortic reconstruction are reviewed, and principles of temporary shunting for allograft protection are proposed.

Forefoot perfusion pressure and minor amputation for gangrene.

In many cases of digital gangrene, limited amputation to preserve the majority of the foot is possible. In the absence of invasive infection, forefoot perfusion pressure is the single most important factor in determining outcome of minor amputation. At ankle pressures of less than 35 mm. Hg, salvage of the foot appears to be futile. The presence or absence of diabetes mellitus has no noticeable effect on the result of amputation. Ankle systolic pressure measurement cannot supplant but should supplement clinical judgement in selecting surgical treatment for gangrene.

Computer processed 99mTc-DTPA studies of renal allotransplants.

In order to refine the diagnostic possibilities of the radionuclide renal study in transplanted patients and to compensate for the nonspecificity of the 131I-hippuran study in some situation, 99mTc-DTPA WAS USED SIMULTANEOUSLY FOR IMAGING AND TIME-ACTIVITY CURVES. For these curves to be significant, appropriate background subtraction had to be made with a simple computer-processing method. The results obtained have shown that it is possible to distinguish marked acute tubular necrosis from milder degrees, thus affording a prognostic index in the immediate postoperative period, when the hippuran data are often nonspecific. Further, the diagnosis and follow-up of acute rejection episodes can be improved by the DTPA processed curves. Although these curves when examined individually do not show a specific pattern for rejection, they may reveal striking evolutionary changes when compared to the previous studies, even when the hippuran curves are unchanged. The physiologic basis for the differences between the two time-activity curves may be related to the differential handling of the two radiopharmaceuticals by the kidney.

The use of photoplethysmography in the assessment of venous insufficiency: a comparison to venous pressure measurements.

In an attempt to develop a noninvasive test to assess objectively the magnitude of venous valvular dysfunction in pathologic states, photoplethysmography (PPG) was compared to venous pressure in the saphenous vein at the ankle. Simultaneous venous pressure and PPG recordings were taken before, during, and after exercise with subjects in the sitting position. In a total of 338 paired measurements in 24 normal, 25 postphlebitic, and 14 varicose limbs, PPG and venous pressure tracings appeared to be identical; data points had a correlation coefficient of great significance (r = 0.898). Postexercise recovery times clearly separated the normal from the postphlebitic limbs. Varicose limbs were assessed accurately regarding results of proposed surgery using an above-knee tourniquet. It appears that the PPG evaluation provides information comparable to venous pressure studies and does so more quickly and noninvasively. The test holds promise in measuring results of direct venous reconstructive surgery as well as in venectomy procedures.

Pelvic hemodynamics after aortoiliac reconstruction.

Changes in blood flow to the pelvis were monitored by measurement of penile blood pressures before and after 38 aortoiliac vascular reconstructions. An increase in penile pressure was noted in 14 patients (37%), a decrease was seen in eight patients (21%), and no change occurred in 16 patients (46%). These changes could have been predicted by matching arteriograms to the surgical procedure performed. Preoperative impotence was present in 27 patients (17%). In this group a postoperative increase in penile pressure was associated with restoration of erectile capability in eight of 11 patients. Only one of 10 patients with an unchanged penile pressure regained sexual potency. In contrast, none of the eight patients whose penile pressures decreased had recurrence of erectile capability. Six of these patients had end-to-end aortobifemoral grafts, and concurrent external iliac disease prevented retrograde flow to the internal iliac vessels.

Surgical correction of chronic deep venous insufficiency by valvular transposition.

Twelve limbs in nine patients undergoing venous valve transposition in treatment of severe chronic deep venous insufficiency are the subject of this report. Hemodynamic measurements including venous pressure studies, photoplethysmography, directional venous Doppler assessment, and impedance plethysmography were done pre- and postoperatively in each case, as was ascending and descending venography. The surgical technique is described in detail and diagrams illustrate general features of the reconstruction. The results show that a functioning valve in the deep venous system of the lower extremity may reverse pre-operative pathophysiology. This preliminary view of the operation indicates that it may have great promise in the field of direct venous reconstruction.

Rational approach to the differentiation of vascular and neurogenic claudication.

Lower extremity pain caused by exercise but relieved by rest is usually a reliable symptom of chronic arterial insufficiency. However, similar discomfort often occurs in patients with neurospinal compression. Furthermore, arterial occlusive disease and demonstrable spinal stenosis may be present simultaneously. Fifty-two patients with symptoms suggesting intermittent claudication comprised the study group. All were proven to have a nonarterial cause of their complaint. The study consists of a retrospective analysis of the diagnostic methods used in confirming the proper diagnosis. Conclusions reached suggest a rational approach to solution of individual patient problems. The nonvascular origin of the symptoms was suggested initially by clinical evaluation in 19 patients, and by noninvasive arterial evaluation in an additional 22. The neurospinal origin of symptoms was obscured in 11 patients because of the presence of significant arterial occlusive disease, as demonstrated by nominvasive arterial testing. Seven of the 11 patients underwent arterial reconstruction, which failed to relieve their symptoms. Subsequently, the neurospinal origin of these symptoms was proven by appropriate treatment. This experience has shown that the errors in diagnosis and treatment could have been avoided by using a combined diagnostic approach, correlating results of an accurate clinical evaluation with noninvasive arterial testing as well as the findings shown on lumbosacral spine films.