P1696Clinical value of QRS spatial dispersion in non-ST elevation myocardial infarction

Background

More than 40% of patients with non-ST Elevation Myocardial Infarction (NSTEMI) have multi-vessel disease with the rate of in-hospital emergent bypass surgery ranging from 11–13%. So, rapid scoring is critical for optimum management even before P2Y12 loading.

Purpose

We aimed to determine the role of QRS dispersion at emergency department, as a simple and rapid sign, in predicting coronary anatomy complexity and in-hospital outcome.

Methods

192 (126 males, age 57.4±6.8 years) patients with NSTEMI and QRS duration <120 ms who underwent coronary angiography were included. QRS dispersion was automatically measured.

Results

Using Spearman's rank correlation, SYNTAX score was found to be positively correlated with admission HR (r 0.54, p value <0.001), maximum HsTnT level (r 0.523, p value <0.001), age (r 0.262, p value 0.015), male gender (r 0.286, p value 0.005), QRS dispersion (r 0.248, p value 0.015), QTc dispersion (r 0.289, p value 0.01), and Grace score (r 0.247, p value 0.015). ROC curve analyses for prediction of SYNTAX score >33 were done for variables with significant correlation. By multivariate logistic regression, male gender (OR 5.042, 95% CI 1.633 –15.567, p value 0.005), admission HR >80 bpm (OR 1.088, 95% CI 1.024 –1.157, p value 0.017) and QRS dispersion >20ms (OR 1.020, 95% CI 1.003 –1.037, p value 0.02) were independent predictors of SYNTAX score >33 (table). Patients with QRS dispersion >20 ms had in-hospital higher Killip class (P<0.001), recurrent ischemia (P 0.003), serious ventricular arrhythmias (P 0.01) and higher GRACE score (P<0.001).

Binary logistic regression for prediction of SYNTAX score >33 Variables Univariate analysis Multivariate analysis OR (95% CI) P value OR (95% CI) P value Age >61 (years) 1.337 (1.019–4.392) 0.015 0.953 (0.878–1.033) 0.242 Male gender 4.851 (2.014–5.301) 0.001 5.042 (1.633–15.567) 0.005 HR >80 (bpm) 3.945 (1.706–6.953) 0.002 1.088 (1.024–1.157) 0.017 QRS dispersion >20 (ms) 2.911 (0.617–13.738) 0.013 1.020 (1.003–1.037) 0.02 QTc dispersion >53 (ms) 6.101 (1.926–19.323) 0.002 2.378 (1.890–2.561) 0.043 Maximum HsTnT >1105 (ng/L) 3.837 (0.236–8.965) 0.004 2.785 (2.501–3.012) 0.034 Grace Score >112 (points) 7.122 (0.632–12.216) <0.001 2.912 (2.703–3.309) 0.030

Conclusion

In NSTEMI, QRS dispersion was positively correlated with SYNTAX score and a cut-off value of 20 ms independently predicted SYNTAX score >33. Regarding in-hospital outcome, QRS dispersion >20 ms was associated with in-hospital higher Killip class, recurrent ischemia, serious ventricular arrhythmias and higher GRACE score

Protective effects of erdosteine against nephrotoxicity caused by gamma radiation in male albino rats

The aim of this study was focused on investigating the possible protective effect of erdosteine against gamma radiation-induced renal lesions in male albino rats. Twenty-eight albino rats were divided into four equal groups as follows: control group, irradiated group (animals subjected to whole-body gamma irradiation at a dose of 5 Gy), treated group (each rat received 100 mg/kg body weight once daily, orally by gastric tube, erdosteine for 1 week), and treated irradiated group (each rat received 100 mg/kg body weight once daily, orally by gastric tube, erdosteine for 1 week, then exposed to whole-body gamma irradiation at a dose of 5 Gy). The results revealed that the administration of erdosteine to rats before irradiation significantly ameliorated the changes occurred in kidney function (creatinine and urea) compared with irradiated group. Also the changes in serum tumor necrosis factor α, interleukin 1β, and interleukin 6 activities were markedly improved compared with the corresponding values of irradiated group. Kidney catalase and glutathione peroxidase (GPx) activities and reduced glutathione concentration showed approximately normal level when compared with the irradiated group. The histopathological results showed distinctive pattern of renal lesions in irradiated group, while in treated irradiated group the renal tissues showed relatively well-preserved architecture. Erdosteine acts in the kidney as a potent scavenger of free radicals to prevent or ameliorate the toxic effects of gamma irradiation as shown in the biochemical and histopathological changes and might provide substantial protection against radiation-induced inflammatory damage.

Effect of dietary Enterolobium cyclocarpum on microbial protein flow and nutrient digestibility in sheep maintained fauna-free, with total mixed fauna or with Entodinium caudatum monofauna

Three groups of five wethers with ruminal and duodenal cannulas and maintained as either fauna-free (FF) or inoculated with total mixed fauna (TF) or Entodinium caudatum as a single-species monofauna (EN) were used in an experiment with two 28 d periods. In the first period, the sheep were fed a control barley-based diet (40:60 concentrate to silage DM) and in the second period the diet was supplemented with 187 g DM of Enterolobium cyclocarpum for the last 12 d of the period. The diets of period 1 and 2 were isonitrogenous. There was no effect of fauna on apparent ruminal and total tract organic matter and fibre digestion, but bacterial and microbial N flow and efficiency were improved in FF sheep compared to TF sheep. In period 2, protozoal numbers were reduced between 31 and 88 % 2 h after feeding E. cyclocarpum for the third to twelfth day of supplementation and by an average of 25 % in samples collected over the 24 h feeding cycle. Supplementation of the diet with E. cyclocarpum and the consequent protozoal reduction in TF and EN sheep improved the flow of non-ammonia N and bacterial N to the small intestine and the efficiency of microbial synthesis. However, E. cyclocarpum reduced ruminal organic matter digestion, especially in faunated sheep, and total tract organic matter, N and fibre digestion. Thus, a reduction in the protozoal cell numbers of 25 % was sufficient to achieve the beneficial effects of reduced fauna on the bacterial protein supply, but diet digestibility was reduced.

The coagulation profile in hepatosplenic schistosomiasis

The biological activity of blood coagulation factors II, V, VII, VIII, IX, X, XI and XII, fibrinogen and prekallikrein was assessed in 15 healthy subjects and 60 patients with endemic Egyptian hepatosplenomegaly. The degree of liver disease was graded according to the Child-Pugh classification, the intensity of S. mansoni infection was monitored by determination of circulating schistosome immune complexes (CSIC) level using a monoclonal antibody and hemostasis activation was detected by measurement of hemostatic markers D-dimer and prothrombin fragment 1 + 2 (F1+2). Functional activity of antithrombin III, alpha2-antiplasmin and protein C as well as quantitative determination of plasma concentrations of alpha1-antitrypsin, C1 activator inhibitor and alpha2-macroglobulin were also carried out. The progressive deterioration of liver function which matched the severity of the disease and the intensity of schistosomal infection led to a reduction in anticoagulant proteins (decreases in antithrombin III and protein C) resulting in hypercoagulability and thrombin generation (increased F1+2) subsequently followed by consumption (prolongation of coagulation screening tests, thrombocytopenia, hypofibrinogenemia and decreased factor VIII resulting in hypocoagulability and secondary fibrinolysis (increased D-dimer and decreased alpha2-antiplasmin). A significant decline in fibrinogen and factors VII, XII and prekallikrein was detected in bleeders compared with ascitic patients. The decline in factor XII was closely related to CSIC high titers in all disease groups, but was not correlated to D-dimer or F1+2 concentrations. This suggests that circulating schistosome immune complexes may exert an inhibitory effect on contact factor XII which should be taken into account when considering the reasons for schistosomal coagulopathy and bleeding in hepatosplenic schistosomiasis.

Laparoscopic resection of posterior gastric leiomyoma

Laparoscopic gastric surgery is gaining momentum, especially in the treatment of benign disease. Simultaneous endoscopy and laparoscopy allow precise localization of lesions. Because of the stomach's size, mobility, and distensibility, relatively large lesions can be safely excised. Wedge resection for anterior lesions and a transgastric or intragastric approach for posterior lesions are feasible laparoscopically. Two cases of posterior gastric leiomyomas successfully resected laparoscopically are presented. The use of stapling devices greatly facilitates this procedure.

Clinical experience with everted cervical vein as patch material after carotid endarterectomy

PURPOSE

The aim of this study was to evaluate the clinical efficacy of everted cervical veins used as patches after carotid endarterectomy.

METHODS

A prospective nonrandomized comparative analysis was performed on patients with either everted cervical veins or saphenous veins as patches after carotid endarterectomy. Two hundred ninety-six patients underwent 329 carotid endarterectomies during an 8 1/2-year period (1987 to 1995). Saphenous vein patches were used in 125 (38%) cases and everted cervical veins in 167 (51%). These two groups were compared clinically and by sonographic surveillance. The mean follow-up of patients in this study was 27 +/- 11 months.

RESULTS

No significant differences were noted regarding postoperative morbid events between the everted cervical and saphenous vein patch groups. Even at 5 years the percentage of patients without stroke for both groups exceeded 95%. Duplex surveillance studies also showed comparable percentages of recurrent moderate (50% to 69%) and severe (70% to 99%) stenosis, 5.6% and 6.9%, respectively, for everted cervical vein and 5.4% and 6.5%, respectively, for saphenous vein. Cumulative recurrent stenosis-free rates at 5 and 6 years exceeded 82% for each of the patch study groups.

CONCLUSIONS

Based on the results of this study everted cervical veins are useful adjuncts to carotid endarterectomy, when patch angioplasty is necessary or desirable. Their performance is comparable to that of saphenous veins. Cervical veins are usually available, even when the saphenous vein is absent or inadequate. In addition, good saphenous veins can be spared and lower extremity excisions avoided.

The milk rejection sign: a natural tumor marker

Early discovery of breast cancer in the lactating female will result in improved survival rates. One such marker is the "milk rejection sign," which has rarely been described and consists of the rejection by the nursing infant of the lactating breast that harbors an occult breast carcinoma. Recognition of this particular sign is vital and will enable early diagnosis and improved prognosis.

Laparoscopic management of acute small-bowel obstruction

BACKGROUND

A retrospective review is given of the authors' experience with a consecutive series of acute small-bowel obstruction unresponsive to medical management.

METHODS

There were 33 exploratory laparoscopies. The etiology was accurately diagnosed in 100% of the cases. Twenty-five (76%) were secondary to postoperative adhesions, of which 18 (72%) were successfully treated by laparoscopic lysis of adhesions. Minilaparotomy was needed to treat iatrogenic perforation (two), gangrenous bowel (one), and Meckel's diverticulectomy (one). Formal laparotomy was utilized for small-bowel resection (two), malignant adhesions (two), and intolerance of pneumoperitoneum (one). Four cases of incarcerated hernias were treated by conventional herniorrhaphy.

RESULTS

Overall, 67% of our cases were spared formal laparotomy.

CONCLUSION

We conclude that laparoscopy is an excellent diagnostic modality in acute small-bowel obstruction, the majority of which can be simultaneously managed laparoscopically. Laparotomy should be reserved for malignant adhesions, surgical misadventure, or when the pathology dictates.

Improved method to create the common ostium variant of the distal arteriovenous fistula for enhancing crural prosthetic graft patency

PURPOSE

Successful use of the distal adjunctive arteriovenous fistula (dAVF) for the enhancement of prosthetic graft patency rates in the crural position is critically dependent on the qualitative and quantitative aspects of the arterial and venous runoff. Precise technical performance of the fistula is equally vital to secure optimal results. The purpose of this study was to determine current prosthetic graft patency and limb salvage rates using a modified version of the common ostium dAVF.

METHODS

The standard method to create the common ostium variant of dAVF has been modified to improve apposition of the "otomy" sites of the artery and vein, avoid twisting and stenosis by terminating the fistula suture line at the artery-vein junctures, reshaping the ovoid ostium to a rectangular shape, and finally, use of multiple interrupted heel-toe sutures.

RESULTS

Since 1979 we have created 290 fistulas in 281 patients who required leg revascularization procedures. In different time periods we have documented improving graft patency and limb salvage rates. Fistula patency, reflected by annual attrition rates of 13% to 26% per year, continues as a challenge for long-term results. Current 3-year secondary cumulative graft patency and limb salvage rates by life table analysis are 61% and 74%, respectively. The conduit material may play a role with regard to steal phenomena and the need for banding techniques.

CONCLUSION

Configuration of the adjunctive dAVF may impact on prosthetic graft patency in the crural position. In addition, the type of graft material used for bypass may be instrumental in preventing or precipitating the steal phenomenon. These issues require further study to better understand flow dynamics, patterns of intimal hyperplasia, and blood distribution as a function of conduit material and impedance of the arterial and venous runoff.

Treatment of cholecystocolonic fistula by laparoscopy

Cholecystocolonic fistula is an unusual complication of biliary tract disease. Many of the signs and symptoms of these fistulas are nonspecific, so the diagnosis is often not suspected preoperatively. It is important to make the diagnosis then to prevent fecal contamination when the fistula is divided. We recently encountered a patient who, while undergoing laparoscopic cholecystectomy, was found to have a fistula between the gallbladder and the proximal transverse colon. Important features in the management of this case are (1) maintaining a high index of suspicion for the presence of this complication, (2) use of cholecystography to establish the diagnosis, and (3) use of laparoscopic stapling techniques to divide the fistula while preventing fecal soilage.

Retained surgical sponge

Surgical foreign bodies are retained more commonly than is suspected. About 50% will become symptomatic in the form of erosion into the bowel or vessels, fistulae, abscesses, obstruction, bleeding, or chronic pain. Expeditious removal is recommended. Laparoscopic retrieval is feasible especially if discovered early.

Experience with a new valvulotome for lower-extremity revascularization procedures by the in situ method

Between November 1990 and November 1992, 50 consecutive cases requiring lower-extremity revascularization by the in situ method were compared with regard to use of two different valve cutters, the Hall valvulotome and the Insitucat. There were no amputations in patients with patent grafts, nor were any infections or false aneurysms noted during the course of this study. In the Insitucat group (n = 25), primary patency was achieved in 19 cases. Five of the six graft failures underwent additional procedures of which three remained patent, adding to the secondary patency rate (22 of 25). The greatest problem with regard to maintaining primary graft patency was that of missed or retained valves, but the incidence of this problem decreased during the course of this study as experience was gained with the catheter in conjunction with angioscopy. Experience with the Insitucat valvulotome has demonstrated its efficacy, though enhanced by monitoring the results with angioscopy. The development and discovery of focal stenotic areas and retained valves by surveillance sonography have resulted in enhanced (assisted) primary graft patency rates. The incidence of these problems appears to be comparable with that occurring with other means of producing valvular incompetence for an in situ reconstruction where valvulotomes of similar design are employed. This was confirmed by comparative analysis with another group of 25 in situ vein bypasses performed during the same time period but during the Hall valvulotome.

Infrapopliteal prosthetic graft patency by use of the distal adjunctive arteriovenous fistula

From November 1979 through December 1989, 210 distal arteriovenous fistulas were constructed as adjuncts to tibial and peroneal vascular reconstructive procedures in 203 patients threatened with limb loss. Two-year cumulative patency rates were calculated by grouping patients on the basis of changing indications in sequential time periods: group 1 (n = 61): 1979 to 1983, 18%; group 2 (n = 80): 1983 to 1986, 33%; group 3 (n = 69): 1986 to 1989, 44%. Although the therapeutic results observed in these groups are not statistically comparable, they show a perceptible trend. Postoperative arteriography showed that flow is prograde in the distal vessels beyond the distal arteriovenous fistula. Graft surveillance by duplex ultrasonography also confirmed that flow in the distal arteries is prograde and that "steal" does not occur. Peak systolic velocity (174 +/- 38 cm/sec) and mean velocity (92 +/- 23) flow rates are increased in grafts with patent distal arteriovenous fistulas compared to those bypasses with closed distal arteriovenous fistulas (p less than 0.01). There were no differences in the flow measurements for the arteries beyond the distal anastomoses and distal arteriovenous fistulas, confirming the prograde nature of the distal flow. In 22 patients analysis of graft and fistula patency by duplex sonography showed that one fourth of all grafts were patent without fistulas at 1 and 2 years after operation. Alternatively, 68% of patent grafts at 1 year had patent fistulas and 58% had patent fistulas at 2 years. We conclude that the distal arteriovenous fistula will increase graft flow and simultaneously prevent distal arterial overload without causing "steal." This technique should be considered whenever a prosthetic graft is necessary for crural reconstruction and only in selected instances of revascularization with autologous veins.

Transmetatarsal amputation: the role of adjunctive revascularization

Over a 12-year period, 160 transmetatarsal amputations were performed in patients with peripheral vascular occlusive disease. The following groups were defined: group 1 - nonreconstructable disease (n = 40); group 2 - transmetatarsal amputation in conjunction with distal revascularization (n = 99); group 3 - reconstructable disease but transmetatarsal amputation performed without simultaneous revascularization (n = 21). There were nine early deaths in the entire series, for an operative mortality rate of 5.6%. The lowest rate of transmetatarsal amputation healing (24%) occurred in group 1. An 86% healing rate was achieved in group 3, but in seven cases (33%) some type of revascularization was required within 3 months of the amputation. In group 2 the healing rate was 62% but reached 83% where the bypass remained patent for at least 3 months after the amputation. Long-term patency rates also affected healing. Healing was not influenced by the number of local procedures (single vs multiple). The presence of severe infection or extensive necrosis necessitated open transmetatarsal amputation in 89 cases; the remaining 71 amputations involved primary closure. Since many patients were treated at a time when diagnostic modalities as well as the operative indications and techniques differed somewhat from the current practice, much of the information regarding group I patients in particular should be considered as a negative historical control and any conclusion from our data should be adjusted accordingly. Healing after amputation at the transmetatarsal level can be expected in the majority of instances in which revascularization can be performed with predictable patency, even when the standard criteria for performing such amputations are liberalized.(ABSTRACT TRUNCATED AT 250 WORDS)

Rupture of arteriovenous fistula after in situ saphenous vein bypass

Residual saphenous vein tributaries function as arteriovenous fistulas after in-situ lower extremity bypass. Whether or not all of these tributaries need to be ligated at the time of bypass is controversial since many will close spontaneously. Other consequences of retained fistulas range from local skin problems to diminished graft flow and ultimate graft thrombosis. A complication not previously reported is rupture of a retained arteriovenous fistula. This unusual and potentially catastrophic complication should be discoverable at an earlier stage by periodic graft surveillance by means of duplex sonography. The routine policy of selective ligation of saphenous vein tributaries needs to be reexamined.

Interval gangrene of the lower extremity: a complication of vascular surgery

Interval gangrene, segmental ischemic necrosis proximal to a functioning distal anastomosis, is a rare complication after successful peripheral vascular reconstruction. Previous reports have demonstrated the gravity of this event in that major limb amputation was required in all cases. Two cases are presented to emphasize the need for maintaining segmental collateral circulation after successful distal extremity bypass. Despite a satisfactory result after distal (inframalleolar) bypass of a popliteal aneurysm, one patient had progressive ischemic gangrene of the upper leg and eventually required amputation. The contralateral limb was successfully managed by distal ligation of the superficial femoral artery, which maintained collateral flow from the proximal superficial femoral artery to the knee and leg. The second patient required a microvascular free flap to replace tissue loss and provide vascular graft coverage after initial multiple bypass failures and a final successful remote reconstruction to the dorsal artery of the foot that excluded the popliteal-crural collateral network. Patients with inadequate collateral circulation or disruption of the profundus or geniculate collateral pathways may require revascularization of sequential vascular beds. Recognition of the potential for interval gangrene is essential since the likelihood of its occurrence will increase in proportion to the number of distal bypasses being performed for limb salvage. Although adjunctive procedures will not completely eliminate the possibility of interval gangrene, awareness of this phenomenon with attention to the segmental collateral circulation can decrease the incidence of its occurrence.

Atheroemboli to the lower urinary tract: a marker of atherosclerotic vascular disease--a case report

Atheroemboli to the lower genitourinary tract may serve as a marker for disseminated atheroembolic disease, a highly lethal condition. A case presentation and review of our institional experience is presented.

Everted cervical vein for carotid patch angioplasty

Because of the theoretic benefits of autologous vein we undertook an investigation to evaluate cervical veins (facial, external jugular) as patch material after carotid endarterectomy. A device that stimulated both circumferential fixation by sutures and radial tension exerted on in vivo patches was constructed to measure burst strength of tissue. Mean bursting pressure for groin saphenous vein (n = 10) was 94.5 +/- 15.1 pounds per square inch (psi), 75.5 +/- 8.9 psi for ankle saphenous vein (n = 10), 83.3 +/- 14.5 psi for everted (double layer) cervical vein (n = 5) and 10 +/- 3.3 psi for single layer cervical vein (n = 5). No significant differences between saphenous vein at any level and everted (double layer) cervical vein, but all were significantly different from single layer cervical vein (p less than 0.05). From June 1987 through November 1989, 19 patients underwent 21 carotid endarterectomies complemented with adjunctive everted cervical vein patch angioplasty. Indications for surgery were asymptomatic stenosis (53%), transient ischemic attack (29%), and cerebrovascular accident with recovery (18%). All patients were studied after surgery with duplex scanning. Asymptomatic recurrent stenosis was observed in one patient. Transient hypoglossal nerve dysfunction occurred in one other patient. One postoperative death occurred as a result of massive aspiration. These results indicate that everted cervical vein is comparable to the saphenous vein in resistance to bursting and can yield similar results as patch material after carotid endarterectomy. Accordingly, saphenous vein can be spared and lower extremity incisions avoided.(ABSTRACT TRUNCATED AT 250 WORDS)

Epidural anesthesia as an adjunct to retroperitoneal aortic surgery

Recent developments in vascular surgery suggest that the retroperitoneal approach to the aorta and the use of epidural anesthesia for lower limb revascularization are associated with decreased morbidity and shorter hospital stays. By combining these principles, we sought to determine if retroperitoneal aortic surgery could be performed under epidural anesthesia and if this might be advantageous. Over a 16-month period, 57 patients underwent aortic surgery via the retroperitoneal (n = 33) or transperitoneal (n = 24) approach. In the former, epidural anesthesia was employed in 10 patients, general anesthesia in 3, and combined epidural anesthesia and general anesthesia in the remaining 20. In the transperitoneal group, general anesthesia was employed in 21 patients and combined epidural anesthesia and general anesthesia in 3. Both groups were similar in age and gender, but risk factors were predominant in the retroperitoneal group. With the exception of one death due to aspiration, there were no significant differences between the transperitoneal and retroperitoneal groups with respect to overall morbidity, pulmonary complications, and length of stay in the intensive care unit and hospital. Despite these findings, we favor the combination of epidural and general anesthesia for retroperitoneal aortic surgery. Morbidity was significantly decreased (p less than 0.05) in low-risk retroperitoneal patients when combined epidural anesthesia and general anesthesia were employed.

Primary aortoduodenal fistula. Diagnosis by computed tomography

A primary fistula between the abdominal aorta and the duodenum is rare and usually fatal. Computed tomography in a symptomatic but stable patient enabled preoperative evaluation and even diagnosis of abnormal communications, real or incipient, between the vascular and enteric system. This case demonstrated the effectiveness, ease, and low cost of documenting a primary aortoduodenal fistula. Surgical results were ultimately improved by initiating early intervention and aggressive management. Therapeutic principles included early intervention with aneurysmectomy, duodenorrhaphy, and extra-anatomic bypass. Anatomic graft placement may be acceptable in selected cases.

Synchronous intrauterine and ectopic pregnancy associated with clomiphene citrate

Although synchronous intrauterine and ectopic pregnancies associated with the use of clomiphene citrate for infertility are rare, the actual incidence might, in fact, be considerably higher than previously thought. The cornerstone for ruling out an extrauterine gestation is the presence of sonographic evidence of an intrauterine pregnancy, as the possibility of concomitant intrauterine and extrauterine gestation is perceived to be statistically rare. This has resulted in an unacceptably high incidence of negative ultrasound interpretations. During a recent 12 month period, four women treated with clomiphene citrate for infertility were diagnosed as having concomitant intrauterine and ectopic pregnancies. Three had pelvic sonograms that were erroneous for the extrauterine component. However, successful evacuation of the products of ectopic gestation was performed in each, despite an immediate preoperative false-negative ultrasound report. Three of the women delivered healthy normal infants at full term, and the fourth woman spontaneously aborted the products of the concomitant intrauterine gestation. All four did well postoperatively, and no gross complications were encountered. Reassessment of ultrasound diagnostic criteria and the use of more sensitive methods, such as endovaginal ultrasound in high risk patients, are indicated for any symptomatic patient using clomiphene citrate for infertility. Awareness of the prevalence of this entity and the limitations of ultrasound will lead to prompt intervention and improved survival rates.

Dual function of the distal arteriovenous fistula for maintenance of arterial and venous prosthetic graft patency in the lower extremity

Venous hypertension, severe swelling, and tissue necrosis occurred in a limb previously subjected to distal arterial bypass plus adjunctive arteriovenous fistula. Occlusion of the popliteal vein had not been recognized during the early treatment period. Subsequent to identification of this mechanism, limb salvage was achieved with an interposition graft of the popliteal vein using externally supported PTFE. The prereconstruction venous pressure gradient of 29 cm H2O was virtually abolished immediately after reestablishing venous outflow. The distal arteriovenous fistula, initially established to maintain prosthetic arterial graft patency, now serves, in this case, a dual function by additionally maintaining prosthetic venous graft patency. An intact deep venous system is critical for achieving successful arterial reconstruction and to avoid the complications associated with an occluded outflow tract in the face of augmented inflow.

Influence of dietary mineral imbalance on the incidence of urolithiasis in Egyptian calves

The influence of certain dietary elements on the urolithiasis syndrome in cattle calves was elucidated. Calcium, phosphorus, and magnesium measurements were conducted on feed rations as well as on serum and urine samples collected from affected and normal calves. Analysis of the rations given to the animals showed phosphorus at higher levels than calcium, indicating mineral imbalance. Serum and urine of urolithic calves were characterised by high phosphorus, calcium, magnesium, urea, and creatinine levels. Physical examination of urine of affected animals showed a high degree of turbidity, a large amount of calcium carbonate, and triple phosphate as well as abundant amount of pus cells and red blood cells. The characteristic clinical symptoms of urine retention were observed. Moreover, some animals were found to urinate through an opening in front of the scrotal region.

Primary and adjunctive intra-arterial digital subtraction arteriography of the lower extremities

Standard contrast arteriography (SCA) and intra-arterial digital subtraction arteriography (DSA) were performed during a 26-month period in 459 cases. The DSA group consisted of 22 aortoiliac studies, 66 crural-pedal arch studies, and 227 combinations. In addition, postoperative DSA was performed in 42 patients to evaluate graft patency, morphology, and inflow and runoff circulations. There were no significant differences in the quality of the preoperative aortoiliac studies performed by either SCA or DSA although, in select cases, one or the other of these techniques resulted in a superior study. Distal crural-pedal arch visualization was enhanced with DSA compared with SCA (85% vs. 65%) but when both were compared with their corresponding intraoperative completion arteriograms, the interpretive error rates resulted in comparable accuracies, false positive and negative rates, and predictive values. The likelihood of achieving graft patency in patients who have unsatisfactory preoperative visualization of the distal circulation by DSA is reasonable (11 of 27 patients) but inferior to the number obtained when there is adequate DSA visualization (40 of 53 patients). We conclude that DSA is a valuable adjunct to preoperative SCA but should not be used as the sole criterion for the assessment of operability for limb salvage. Intraoperative prereconstruction arteriography or direct surgical exploration of the crural arteries in patients with inadequate preoperative visualization will result in graft patency in a significant percentage of cases. Intra-arterial DSA for postoperative evaluation of lower limb bypass adds another dimension to analysis of graft structure and status of the host circulatory beds and also provides a method for accurate interpretation of postoperative data.

Omental protection of autogenous arterial reconstruction following femoral prosthetic graft infection

Vascular graft infections in the femoral region that require synchronous revascularization are generally reconstructed with prosthetic grafts via extra-anatomic routes. If in situ revascularization is required, then autologous tissue provides optimal results. A particular challenge in this circumstance is achieving soft tissue coverage of the reconstruction where wide and radical débridement has removed the tissues ordinarily used for this purpose. If muscle flaps are not available or possible, the use of omentum is advocated. The omentum can be easily reached from behind the inguinal ligament and transposed on its bipedicled vascular base for coverage of vital structures in the femoral triangle, thereby obliterating dead space and providing a surface for both temporary and permanent skin coverage. The procedure is quite simple, can be performed rapidly, and should be considered for use in the dire situation that requires soft tissue coverage of exposed vessels in extraperitoneal locations.

Adventitial cystic disease of the popliteal artery: failure of percutaneous transluminal angioplasty as a therapeutic modality

Adventitial cystic disease of the popliteal artery is an important cause of peripheral vascular insufficiency in the young and middle-aged man. The pathologic feature is a mucinous cyst located within the adventitia of the artery that expands and secondarily compromises the vessel lumen. Although physiologically quite different, this process is easily mistaken for arteriosclerosis. The clinical history of sudden claudication in a young nonsmoking man, combined with characteristic angiographic features, are important clues to the correct underlying pathology. Treatment generally consists of cyst evacuation or local bypass. This article was prompted by the failure of percutaneous transluminal angioplasty to achieve durable success in controlling this unique type of arterial disease. Subsequent surgical intervention proved satisfactory, lending support to this modality as the treatment of choice.

Improved patient selection for enzymatic lysis of peripheral arterial and graft occlusions

Intraarterial thrombolysis by remote intravenous or direct intraarterial infusion of streptokinase is possible. The latter may be more effective with a lesser potential for systemic hemorrhagic complications because of the smaller dose administered directly in the area. Fifty patients with prosthetic graft, embolic, and renal artery occlusions were evaluated. Embolic occlusion responded dramatically, particularly since lytic therapy was initiated at an early stage. Patients with severe ischemia or those with simple localized occlusion were best treated by surgical means. Successful thrombolysis was also obtained with renal artery occlusions combined with percutaneous transluminal angioplasty. The management of patients with prosthetic graft occlusion by lytic therapy is complex. Optimal results can be obtained in patients presenting with occluded grafts after the immediate postoperative period and in those in whom previous satisfactory runoff has been demonstrated. Failure of lysis in this group is associated with a high incidence of limb loss due to unreconstructable obliterative disease. Successful lysis of occluded prosthetic grafts will often require corrective angioplasty or surgical revision.

Lysis of arterial clot by intravenous or intra-arterial administration of streptokinase

Intra-arterial thrombolysis with streptokinase was studied in 38 patients. The indications were peripheral thromboembolism in nine patients (group 1), postreconstruction graft thrombosis in 26 patients (group 2) and renal artery thrombosis in three patients (group 3). The intra-arterial route was used for the first and third groups and in 16 of the second group. The intravenous route was used in the remaining ten patients. Lysis was achieved in all of the group 1 and 3 patients. The latter were also treated with percutaneous transluminal angioplasty after dissolution of thrombus of the renal artery. In group 2 patients, lysis was achieved in eight of 16 patients in whom lytic therapy was instituted within seven days of graft closure. There was no lysis in all ten patients in whom elapsed time was more than seven days. Postlytic angiographic visualization of etiologic mechanisms for thrombosis enabled subsequent successful correction in three of five patients in group 2. Attempts to correct graft failure by surgical treatment when lysis had failed were often unsuccessful (12 of 17). Lytic therapy is most effective for acute embolic occlusion and for thrombosis of less than seven days duration. Although there is no difference in drug efficacy by route of administration, a lesser number of complications (such as, fever and hematoma) occurred with intra-arterial infusion. The effectiveness of lysis is also directly related to the collateral circulation and runoff beyond the occlusion. Lysis is not indicated for severe acute ischemia if surgical treatment is an alternative or if it may cause distal embolism as with complete axillofemoral graft thrombosis. Lytic therapy is least effective for graft thrombosis with pre-existent poor runoff.

Biodegradation and aneurysm formation in umbilical vein grafts. Observations and a realistic strategy

In a series of 756 glutaraldehyde-stabilized umbilical vein grafts implanted over a 7 1/2-year period, aneurysms were identified in seven cases. The earliest aneurysm was seen at 31 months after implantation and the remainder between 43 and 79 months after surgery. Corrective surgery was performed in five cases and succeeded in four. Although definite mechanisms have not been identified, mechanical fatigue, reversal of aldehyde crosslinks, and immunologic factors may be operative. The pathologic changes include: (1) actual dilation of both graft and mesh with or without intraluminal thrombus and, (2) maintenance of graft diameter with erosion of the umbilical vein and polyester mesh rupture leading to perigraft hematoma and false aneurysm formation. Microscopic examination and infrared spectral analysis confirmed the presence of host-contributed lipid in some specimens. Although this is a low incidence of aneurysm formation, umbilical vein grafts should be selected primarily for patients with limited life expectancy or for whom alternative materials with comparable or superior patency rates are not available or acceptable. Periodic angiography, particularly after 3 or 4 years, is recommended as a routine part of follow-up examinations. Improved graft materials and control of host environmental factors are potential means to reduce the noted degradation.

Combined thrombolysis with low-dose streptokinase and angioplasty in the treatment of renal artery occlusion

A case of acute renal artery thrombosis superimposed on a stenotic atheromatous lesion treated with low-dose streptokinase thrombolysis and percutaneous transluminal angioplasty is presented. Renal function was promptly improved. This combined approach is recommended in selected elderly and seriously ill patients.

Distal arteriovenous fistula as an adjunct to maintaining arterial and graft patency for limb salvage

Sixty-one distal arteriovenous fistulas (dAVFs) were constructed as adjuncts to tibial and peroneal vascular reconstructive procedures in 58 patients threatened with imminent limb loss. Specific indications for dAVF construction were absent or deficient pedal arches, usually associated with small, calcareous crural vessels. Conventional bypasses had been previously performed in 35 patients. Cumulative graft patency rates were 56%, 39%, and 18% at 6, 12, and 24 months, respectively. For the same intervals, the figures were 56%, 52%, and 52% (P less than 0.001 at 24 months) for nonAVF reconstructions (n = 49). The corresponding cumulative limb salvage rates were 62%, 52%, and 40% for the dAVF group and 78%, 72%, and 72% for the nonAVF group (P less than 0.05 at 24 months). The perioperative mortality rate was 7% (four of 61). Twenty-four amputations were required, of which 16 were below the knee and six despite patent grafts. There was no significant morbidity attributable directly to the dAVF. Cardiac output showed no deviations from normal values. Primary causes of early failure were infection (n = 4), absence of satisfactory veins (n = 6), and inappropriate case selection (n = 7). Intimal hyperplasia led to dAVF closure and graft failure in 13 patients. This study shows that dAVFs can maintain graft patency by diversion of the overload on a high-resistance vascular bed and, secondarily, by augmentation of inflow. Immediate survival of the limb still depends on the arterial runoff, as retrograde venous flow caused by venous valvular incompetence is a delayed development. Adjunctive dAVF is justified in selected cases where conventional bypass failure has occurred or is predictable by increased pedal vascular resistance.

Influence of failed vascular bypass procedures on conversion of below-knee to above-knee amputation levels

From 1975 to 1980, 79 major limb amputations were performed from a group of 552 lower extremity vascular reconstructions with glutaraldehyde-stabilized umbilical vein grafts. All amputations were performed in instances in which limb salvage had been the indication for the attempted bypass (n = 520)--an incidence of 15.2%. Twelve of 51 below-knee (BK) amputations were converted to above-knee (AK) levels (crude failure rate, 23.5%). The highest crude failure rate occurred after failed bypass to the popliteal artery (33.3%); the lowest occurred after failed tibial bypass (16.7%), and the peroneal arteries were intermediate (22.2%). In addition to these 12, 28 primary AK amputations were performed. Excluding nine cases judged to require AK amputations before the attempted vascular reconstruction, success/failure rates for the entire series and each of the reconstruction types were calculated. Success, defined as a healed BK stump, occurred least after failed popliteal bypass, 44.5%, compared to 71.4% and 53.8% for the tibial and peroneal groups, respectively. Thus, failure of a popliteal bypass was more apt to lead to an AK amputation (56.5%) than failure of a distal bypass. In fact, tibial bypass failure leading to an AK stump occurred at a frequency (28.6%) almost similar to that obtained by other investigators when no previous bypass had been performed. Comparative cumulative graft patency and limb salvage rate data confirm the value of reconstructive vascular surgery, particularly in the peroneal group where negativism with regard to its clinical usefulness persists. With improved case selectivity and surgical expertise, increasing limb salvage rates can be secured while minimizing the definite morbidity of conversion of BK to AK amputation with failed vascular bypass.

Tibial arteriovenous fistula: successful use for limb salvage

Embolization of atheromatous material from abdominal aortic aneurysms to the distal arterial circuit is a well-recognized clinical entity causing the "blue toe syndrome." A case is presented in which this phenomenon resulted in obliteration of the pedal arch and thrombosis of the tibial arteries. As a result, forefoot gangrene, severe leg ischemia and anterior and posterior compartment syndromes occurred. Salvage of the extremity required an extraordinary approach with the construction of an arteriovenous fistula between the posterior tibial vessels. The literature on the use of therapeutic and adjunctive arteriovenous fistulas and their physiology is discussed.

Morphologic structure of the pedal arch and its relationship to patency of crural vascular reconstruction

Pedal arch integrity can be determined morphologically and functionally. The former is accessible by contrast studies and intraoperative catheterization, the latter, by flow studies and observation of graft patency. The roengten image of an intact pedal arch corresponds to the anatomic plantar arch. Sixty-four arch studies obtained by adequate intraoperative arteriography were categorized as intact, deficient or inadequate or absent. Patency of crural reconstructions was obtained in 18 of 24 patients with intact arches as compared with 15 of 32, p<0.06, when the arch was deficient. Crural reconstruction in the face of an inadequate or absent arch resulted in predictable graft closure. Qualitative factors, that is, size, calcium and stenotic lesions, are integrally related to over-all graft performance even with intact arches. The deficient arch for tibial and peroneal reconstruction continues as a challenge to the vascular surgeon.

Remote profunda femoral bypass for limb salvage

Patients with patency of the distal segment of the profunda femoral arteries can be subjected to a direct end-to-side bypass with either tissue or synthetic grafts to increase blood flow to the lower extremity. The effectiveness and durability of this procedure will be enhanced by patency of the popliteal artery. Diffuse profunda femoris disease, popliteal or tibial peroneal obliterative disease and gangrenous lesions tend to militate against the success of this operation as an isolated procedure without augmenting flow to the distal part of an artery in the leg. Of 18 remote profunda femoris bypasses performed during a four year period, early amputation was required in two patients because of inadequate distal flow and the inability to establish downstream reconstruction. In one patient, an early bypass to the peroneal artery was required following closure of the profunda femoris bypass. The remaining 15 bypasses resulted in limb salvage and significant relief of symptoms. Three patients subsequently required secondary downstream reconstructions. The profunda femoris is surgically accessible for a long length and can serve as an adequate source of blood to the leg and foot in selected patients.

Adjunctive arteriovenous fistula with tibial and peroneal reconstruction for limb salvage

Arteriovenous fistulas were constructed as an adjunct to femoral peroneal and tibial bypasses in 13 patients threatened by imminent limb amputation. Previous attempts at conventional vascular reconstructive procedures had failed in nine patients. Deficient or absent pedal arches were noted in all patients, as were poor quality or small crural arteries. Graft patency was achieved in 11 cases and limb salvage in 10. There was no mortality. A steal phenomenon occurred in one patient and was successfully treated by secondary popliteal vein ligation. These preliminary results clearly indicate that an adjunctive arteriovenous fistula can maintain patency in a femoral tibial or peroneal bypass graft while preserving flow into the markedly diseased distal circulation.

Three-year experience with glutaraldehyde-stabilized umbilical vein for limb salvage

During the past 3 years, 361 vascular reconstructions were performed employing glutaraldehyde-stabilized umbilical veins. The distal anastomosis terminated at the popliteal segment (n = 183), at either of the tibial arteries (n = 108) or at the peroneal artery (n = 70). One hundred and forty-one (77 per cent) of the popliteal reconstructions were below the knee. Many of the patients undergoing these bypasses had a previous failed reconstruction and were operated upon for limb salvage. Operative mortality rates for the popliteal, tibial and peroneal reconstructions were 2·7, 2·8 and 4·3 per cent respectively. Cumulative graft patency rates at 36 months for each of the three types of reconstruction were 76·4 per cent (popliteal), 63·4 per cent (tibial) and 39·8 per cent (peroneal). Failures were usually due to inappropriate case selection or progressive disease, particularly in the distal circulation. Two grafts were removed because of wound and secondary graft infection. There were no instances of biodegradation, either by aneurysm formation or by myointimal proliferation. These data confirm that attempts at revascularization are definitely preferable to amputation. The use of the glutaraldehyde-stabilized umbilical vein has facilitated the performance of these operations. In appropriately selected cases and with expert surgical technique, long term graft function with limb salvage can be obtained.

Remote hydraulic syringe actuator: its use to avoid radiation exposure during intraoperative arteriography

A simple, inexpensive device consisting of a double hydraulic syringe system and a holding fixture was devised for intraoperative arteriography to avoid exposure of personnel to radiation. The procedure of intraoperative angiography has thus become safer, less time consuming, and more reliable in obtaining high-quality angiographic studies.

Synchronous aortofemoral or iliofemoral bypass with revascularization of the lower extremity

Bypassing aortoiliac stenosing lesions to the profunda femoria alone, even with extensive end-arterectomy and angioplasty of the latter, will not provide predictable excellent results in the presence of gangrene and occlusion in the femoral popliteal system. With severe pregangrene and rest pain, residual ischemic complaints are also common, and if lesions are present, healing is incomplete or, at best, delayed. Alternatively, femoropopliteal or tibial bypass, in the presence of even moderately diminished inflow, is subject to either early or delayed closure, unless proximal repair is also performed in appropriately selected patients. Synchronous correction of tandem lesions involving the aortoiliac and femoropopliteal segments should, therefore, be considered for limb salvage only and particularly in the presence of focal gangrene, excision or debridement of which can be anticipated to heal after successful bypass. Major diminution in femoral inflow usually indicates the need for proximal repair only, even in the presence of distal lesions. Noninvasive studies and intraoperative flow determinations are not uniformly helpful in patient selection. Synchronous aortofemoral or iliofemoral and femoropopliteal or tibial reconstructions were performed upon 38 patients, 15 of whom had no prior vascular operation and 23 of whom had previously undergone either aortofemoral or femoropopliteal bypasses that had failed. Graft patency for all patients was 76 per cent, and although it was better for the patients in group 1 than for those in group 2, no statistical significance existed between the two groups. Improved patient selection and criteria for performing synchronous reconstructions might originally have been of benefit for the patients in group 2, avoiding more difficult secondary repairs. It must be emphasized, however, that synchronous reconstructions should not be done routinely in the presence of multilevel disease. Rather, specific indications do exist and should be considered on an individual basis.