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Although use of thrombolytic therapy during primary angioplasty is controversial, the development of a monoclonal antibody (c7E3 Fab) to the platelet glycoprotein IIb/IIIa receptor has been a tremendous breakthrough in the field of interventional cardiology. Use of the antibody during high-risk angioplasty or atherectomy procedures has been shown to significantly reduce the incidence of death, MI, or emergent repeat revascularization. We describe four cases in which c7E3 Fab was used as an adjunct to coronary stenting in the peri-infarct period in patients with cardiogenic shock. To our knowledge, no other reports have addressed the use of glycoprotein IIb/IIIa receptor inhibitors with coronary stent implantation. Our experience in this small population suggests that coronary stenting for myocardial infarctions may be a feasible option in selected patients to allow maximal luminal dilation and successful reperfusion. We emphasize that our results are preliminary, and we eagerly await the results of the EPILOG study which will provide more definitive data on the safety and efficacy of c7E3 Fab and coronary stenting from the perspective of a large, randomized trial. © 1996 Willey-Liss, Inc.

A case of intrapericardial giant lymph node hyperplasia (localized hyaline-vascular variant of Castleman's disease) is reported. The large tumor was successfully removed, and at a twelve-year follow-up there are no signs of recurrence. This is the first case reported in the literature of an intrapericardial Castleman's disease localization. Embryologic, surgical, and prognostic implications of this finding are briefly discussed.

An axillodistal abdominal aorta bypass graft is proposed as an alterative procedure for revascularization of the lower limbs when intraabdominal and intrathoracic approaches are not feasible. This simple and safe procedure is proposed instead of the axillobifemoral bypass graft for the treatment of selected patients with abdominal aortic occlusive or aneurysmal disease and aortic graft infection. A case of a patient who underwent axilloabdominal aortic grafting because of a ruptured infrarenal abdominal aortic aneurysm, combined with severe chronic obstructive pulmonary disease, is reported.

A case of a popliteal aneurysm presenting as a deep vein thrombosis of the lower extremity is reported. Venous insufficiency symptoms, like presenting symptoms of a popliteal artery aneurysm, are an uncommon occurrence but often cause a wrong or delayed diagnosis with severe consequences for limb salvage. The importance of an accurate diagnostic study in any patient with a suspected deep vein thrombosis is emphasized in this report.

In order to determine factors influencing operative and long-term patency of bypass grafting for upper extremity ischemia, a fifteen-year experience with 39 bypass grafts was reviewed. Etiology of the lesions included atherosclerosis in 17 limbs, thoracic outlet syndrome in 7 cases, violent or iatrogenic trauma in 12 cases, and arteritis in 3. Primary lesions affected the innominate, subclavian, axillary, and brachial artery in 2, 19, 8, and 10 cases respectively. All patients had a complete follow up (mean seventy-one ± forty-four months). The thirty- day, one-year, and five-year patency rates were 92%, 81%, and 78%, respec tively. Indications for operation and type of onset of ischemic symptoms significantly influenced graft patency (p

From January, 1973, to December, 1987, 63 arterial revascularization procedures were performed in 50 pa tients suffering from brachial artery injuries following cardiac catheteriza tion. There were 15 occlusive compli cations (30%) after the primary attempt to revascularize the damaged brachial artery. Thrombectomy asso ciated with a simple repair of the arte rial cutdown (Type IA) led to 8 compli cations of 9 procedures performed. Technical details of repair of the dam aged artery—debridement, venous patch graft, resection, end-to-end anastomosis, and venous bypass inter position—were found to be important and led to long-term patency.

Sealed rupture of abdominal aortic aneurysms, even if uncommon, deserves particular attention for the possibility of misdiagnosis and for the deleterious effects of such a misdiagnosis. Sixteen patients (mean age 72 years; range 65 to 84 years) with chronic sealed rupture of abdominal aortic aneurysms are reported. Two patients had acute rupture of the aneurysm, and at operation chronic contained rupture was found along with the recent hemorrhage. One patient died after surgery. The remaining patients underwent successful resection with long-term survival and regression of symptoms. Consideration of sealed abdominal aortic aneurysm rupture should be included when examining elderly patients with history of unexplained back pain or femoral neuropathy. Computed tomography is a useful aid in the diagnosis of sealed rupture. Ultrasonography is less accurate; in three patients ultrasonography failed to diagnose the presence of the rupture. (J VASC SURG 1990;11:430-5.)

Conditions required for in vitro bonding of14C-ofloxacin (OFX) to polytetrafluoroethylene suture (PTFE) were investigated. Bonding of OFX to PTFE was enhanced 22- and 75-fold in the presence of the cationic surfactant benzalkonium chloride (BAC) or silver and organic solvents (S/O), respectively. The optimal temperature and time of incubation for maximum OFX bonding was 37°C for 1 h (BAC) and 37°C for 25 min (S/O). BAC- and S/O-treated PTFE bound 3.94 nmoles and 17.79 nmoles OFX/cm suture. Prolonged in vitro incubation of OFX/PTFE for 7 days at 37°C in the presence of serum or saline resulted in 50% OFX retention. In vivo studies on OFX/PTFE placed into canine carotid arteries showed 8% OFX retention. The intravenous infusion of coagulase-positiveStaphylococcus aureus into OFX/PTFE animals resulted in colonization. Although significant in vitro bonding of OFX to PTFE was observed, in vivo studies demonstrate an accelerated release and inferior OFX/PTFE activity against microbial colonization.

Post-endarterectomy platelet deposition may play an important role not only in vessel wall healing, but also in the development of progressive stenosis. Using a canine model, we investigated the effect of endothelial cell seeding on platelet deposition on endarterectomised arteries. Thirteen dogs underwent bilateral carotid intimectomy (5 cm long) and one side was seeded with an average of 2 × 10 6 viable freshly harvested endothelial cells. Blood flow was restored 20 min after seeding. On the contralateral side, a sham-seeding was performed. Deposition of 111 indium-labelled autologous platelets was studied with sequential gamma camera images 3–5h, 1, 2, 3, 4 days and 4 weeks after surgery. Platelet uptake was statistically reduced on the seeded side. Animals were killed at 4 weeks (nine dogs) and 5 weeks (four dogs) after surgery. Seven arteries for each group were found to be occluded. We conclude that endothelial cell seeding on endarterectomised arteries is feasible and reduces platelet uptake. Improvement in the efficiency of seeding and reduction of endothelial cell loss might permit clinical application of this technique.

The results of 26 carotid-subclavian bypass (CSB) and 17 axillo-axillary bypass (AAB) procedures, performed to treat symptomatic lesions of the proximal subclavian artery, were reviewed. Nine graft failures (seven CSB and two AAB) occurred (mean follow-up: CSB = 60.5 +/- 41 months; AAB = 67.8 +/- 48 months). All CSB graft thromboses were observed in patients with an associated ipsilateral carotid lesion, surgically treated or not (p less than 0.05). Cumulative 5- and 10-year patency rates were 78.3 and 62.9% for the CSB group and 87.9% for the AAB group (N.S.). In patients with an associated ipsilateral carotid lesion, 5- and 10-year patency rates were 66.0% and 40.8% for the CSB group and 100% for the AAB group (p less than 0.05). Both the surgical procedures were safe and effective with excellent results in terms of operative mortality, major morbidity and long-term patency. CSB is the procedure of choice for the treatment of proximal subclavian artery disease for its physiological characteristics and for graft shortness. However AAB must be considered a suitable alternative and preferred when a concomitant ipsilateral carotid lesion is present. Recurrence of carotid stenosis or carotid lesion progression may cause the carotid-subclavian failure.

Although the hemodynamic characteristics and durability of the St. Jude valve prosthesis have been reported, the need for and the degree of anticoagulation in patients who receive these valves remain uncertain. Our 10-year experience with 165 patients (100 men and 65 women, mean age of 58 ± 13 years), who underwent valve replacement with St. Jude prostheses, is reported. Of the 165 patients, 147 were treated with warfarin. A prothrombin time 1.3 to 1.8 times control (range 15 to 20 seconds) was maintained in 134 patients with single valve and 1.8 to 2 times control (range 20 to 25 seconds) in 13 patients with double valve prostheses. The 10-year actuarial event-free incidence from thromboembolic and hemorrhagic complications was 84 and 95%, respectively. Of the 8 patients receiving antiplatelet therapy alone, 4 had thromboembolic events. Of the 10 patients on neither warfarin nor antiplatelet therapy, 3 had thromboembolic events. The 10-year actuarial event-free incidence from valve failure was 95%. The 10-year actuarial patient survival was 55%. Thus, the St. Jude valve is a safe and reliable prosthesis with acceptable overall long-term performance in patients given a modest anticoagulation regimen. Patients who receive St. Jude prosthetic valves without anticoagulants have a high incidence of thromboembolic events despite therapy with antiplatelet agents.

The purpose of the study was to compare two different techniques for isolation of omental microvascular endothelial cells (ECs). Segments of unreinforced polytetrafluorethylene (PTFE) grafts, 9 cm long and 6 mm in diameter, were implanted in 22 dogs as an aortic interposition. Fourteen grafts were seeded with a mean of 7 x 10(5) viable ECs, derived from the microvessels of the omentum: eight grafts (group A) were seeded with ECs obtained by collagenase digestion and by filtration through a pore mesh; six grafts (group B) were seeded with ECs obtained by collagenase digestion and by Percoll gradient separation. In eight grafts (group C), the ECs were not added to the preclot mixture and served as a control. Animals were sacrificed 5 weeks after surgery. The percentage of thrombus-free area was 65 +/- 22% for group A grafts and 74 +/- 15% for group B grafts (NS). The subendothelial layer was 280 +/- 60 microns thick in group A and 220 +/- 30 microns thick in group B (P less than 0.05). Seeded grafts showed a higher production of 6-keto-PGF1 alpha after addition of sodium arachidonate than control grafts. Percoll gradient separation allows isolation of a more purified suspension of ECs. Refinements in omental EC procurement are still required to minimize contamination with other types of cells.

To determine factors influencing results of operation for proximal brachiocephalic arterial disease, a 16-year review of 74 consecutive patients was undertaken. A total of 62 subclavian, 14 common carotid, 6 innominate, and 2 vertebral arteries were revascularized during 79 procedures. The approach was transthoracic in 12 operations and extrathoracic in 67. Mean follow-up was 57 +/- 45 months. Two patients (2.5%) died of stroke after extrathoracic revascularization of the common carotid artery. Cumulative 5-year and 10-year freedom from neurological events was 81% and 75%, respectively. The best results were obtained with transthoracic procedures, with revascularization of the subclavian artery rather than the common carotid artery, and in operations performed in patients without associated distal carotid disease. In view of the recent progress in operative techniques and postoperative surgical care, the choice between the transthoracic approach and the extrathoracic approach should not be biased; rather, they should remain equal and viable alternatives based on anatomical and clinical features of the individual patients.

During the last fifteen years, we performed a total of 855 aortofemoral re constructions. Fifteen (1.75%) grafts were surgically removed (completely or partially) owing to a severe infection (Szilagyi: Grade 3) at a mean of 66.3 months (SD ± 37.9) after their implantation. Diagnosis was always clinically evident. In 10 patients, the graft was partially removed (one or two limbs). In 3 of the 10, graft infection progressed requiring complete graft removal after a mean of 18.6 days. In the other 5 patients, the graft was removed "in toto" at the time of the first operation. In 9 cases, revascularization was accomplished by means of a "remote" takeoff reconstruction (thoracic aorta or axillary ar tery), whereas in 8 cases (3 recurred) reconstruction was performed with a "local" takeoff reconstruction (stump or aortoiliofemoral arteries). One patient was not revascularized, because the limb was already amputated. Recurrence of infection was higher in the patients treated by partial removal of the graft (p < 0.05), even though the stump sterility was always evaluated by means of intraoperative culture. The mortality of patients with recurrence of infection was 66.6%. Multiple operations of the femoral site were considered a factor in causing aortofemoral graft infection (p < 0.01). Diabetes was not considered a factor in causing infection (p n.s.). Grafts with remote takeoff reconstruction have better long-term results in terms of limb salvage and survival when compared with local takeoff recon struction (p < 0.05).

Aneurysms of the aorta are rare in children and young adults. We report a case of a 19-year-old man with a saccular abdominal aortic aneurysm (AAA). No associated disorders were discovered in this patient. The aneurysm was resected and a Dacron aortic graft was implanted. Nine years after operation the patient was in good health without evidence of other aneurysms. Thirty-two cases of probable congenital abdominal aortic aneurysms were collected from the literature. In 19 cases, the cause of the aneurysm was not ascertained. We identified two groups of patients with probably congenital AAAs: type I congenital AAA, in which there is a generalized disorder of the arterial tissue and usually aneurysms are present in other areas and type II congenital AAA, in which there is a localized defect of the abdominal aorta, without aneurysms in other areas. We speculate that a congenital defect localized to the wall of the abdominal aorta was the cause of the aneurysm in this patient (type II congenital AAA).

The records of 125 patients 75 years of age or older with a diagnosis of unruptured abdominal aortic aneurysm were reviewed. Operative mortality was 4.3 percent in 69 patients considered at low risk and 39.8 percent in 13 patients at high risk who underwent aneurysmectomy shortly after diagnosis. Forty-three patients with an asymptomatic abdominal aortic aneurysm initially measuring 3.5 to 6 cm did not undergo aneurysmal resection and were followed for 6 to 72 months (mean 24 months) with serial echography. The mean enlargement rate was 0.48 cm/year. In the 43 patients, resection of the abdominal aortic aneurysm was performed for aneurysmal expansion to greater than 6 cm, development of symptoms, or a sudden change in aneurysmal diameter. Two patients were lost to follow-up, 21 underwent elective resection, aneurysms ruptured in 2, 9 died from other causes, and 9 were alive and asymptomatic at last follow-up. An aggressive surgical approach seems appropriate, even in the asymptomatic elderly patient with a small aneurysm of 4.5 to 6 cm. Serial echographic measurement appears useful in determining which patients with a very small aneurysm of less than 4.5 cm or who are considered to be high risk surgical candidates require elective aneurysmectomy.

A 7-year experience with 90 polytetrafluoroethylene (PTFE) femoropopliteal bypass grafts in the above-knee (AK) position is presented. The 5- and 7-year actuarial patency rate was 58.3%. No statistical difference was found between the patency rate of this series and that of a group of 17 AK and 77 below-knee (BK) femoropopliteal bypass grafts performed during the same period with the autologous saphenous vein (ASV). During the follow-up period (range 6 to 84 months, mean 42 months) a new bypass in a more distal location was required in 20 limbs. The ASV was available in seven of the eight PTFE graft failures and in only one of the 12 ASV failures. The 3-year patency rate of these new groups was 58.3% and 16.7%, respectively (p

Among 486 patients undergoing repair for abdominal aortic aneurysm (AAA) during a 12-year period, 30 (6.2%) had evidence of "inflammatory" AAA. One patient (3%) had acute rupture, and six patients (20%) had chronic contained rupture. Ureteral obstruction was evident in 20% of the patients. In the early period of the study there were two postoperative deaths and operative time and blood loss were significantly increased. In the last period of the study, no attempt was made to separate the duodenum and the ureters from the aneurysm; there was no operative mortality, and operative time and blood loss were similar to that of patients with atherosclerotic aneurysms. In 23 of 100 specimens of atherosclerotic AAA, microscopic findings resembling inflammatory AAA were found. On the basis of our study we conclude the following: (1) Inflammatory AAAs are simply atherosclerotic aneurysms that show an unusual accentuation of the chronic inflammation observed in relation to atherosclerotic aneurysms. (2) Operative technique should be modified to avoid excessive dissection and lysis of ureters and duodenum. (3) Excellent early and late results can be expected with proper surgical technique. (4) The causes of AAA are multiple, and chronic contained rupture of the aneurysm and reactive lymphatic hyperplasia might play a role of greater significance than previously thought. (J Vasc Surg 1989;9:643–50.)

From May 1974 to October 1983, 82 patients with severe bilateral carotid disease had unilateral carotid endarterectomy (CE) on the symptomatic side (group I). The carotid artery contralateral to the endarterectomy was severely stenosed (lumen diameter reduction 51% up to 99%) and it was not repaired for different reasons. Group I patients were compared with 78 patients who had bilateral CE (group II), matched with group I for associated diseases, operative indication, and angiographic findings. In this analysis, only neurologic deficits referable to the contralateral hemisphere were considered. There was a higher incidence of later neurologic deficits in the group I patients; however, this difference was not statistically significant. In group I, the occurrence of late neurologic deficits was statistically correlated to (1) severity of stenosis, (2) presence of large compound ulceration, and (3) history of previous stroke. Stepwise logistic regression analysis identified two groups of patients at higher risk for late neurologic deficits (1) patients with stenosis 75% or greater and large ulceration and (2) patients with stenosis 75% or greater and previous stroke. CE on the asymptomatic contralateral side should be considered in selected patients at high risk for late neurologic events at a surgical center with an established low incidence of perioperative complications. A nonoperative policy with careful follow-up is warranted in the remaining cases. (J VASC SURG 1988;8:453-9.)

A modified technique of profunda femoris artery reconstruction is presented. In case of occlusion of the superficial femoral artery, the proximal segment of this vessel is rolled over the profunda femoris artery as a patch after an endarterectomy has been performed. This technique has been performed in 110 patients (131 limbs) during the last 14 years. Five-year actuarial patency rate (life-table method) was 65.3%. With measurements obtained from nine biplanar angiograms, glass models of three different methods of profunda femoris reconstruction were constructed. The model representing this modified technique of profundaplasty showed less turbulence than the others. The results of this study validate the use of this type of profundaplasty in clinical practice.

The success of aortofemoral reconstruction in patients with superficial femoral artery occlusion depends on the restoration of a satisfactory pulsatile flow to the deep femoral artery. In 18 patients with multilevel disease, widespread involvement of the deep femoral artery, and poor distal outflow, we performed an eversion endarterectomy of the proximal segment of the superficial femoral artery and constructed an end-to-side anastomosis between this segment and the distal deep femoral artery. In 10 patients, the reconstruction was performed after thrombectomy of the occluded aortofemoral graft, and in 8 the two reconstructions were simultaneous. The actuarial patency rate was 93.5 percent at 1 year and 75.2 percent at 5 years. Four late femorodistal bypasses were performed that gave an actuarial limb salvage rate of 68.8 percent at 1 year and 61.6 percent at 5 years. In selected cases, this technique is a valid alternative to an extended profundoplasty or to a femorodistal bypass.

In the past 14 years, 22 patients (25 operated sides), with occlusion of the internal carotid artery (ICA), underwent ipsilateral external carotid artery (ECA) endarterectomy at our institution. Operative indications were amaurosis fugax in 13 sides and nonlateralizing transient ischemic attacks in the remaining 12. There were no operative deaths. One patient suffered a minor stroke after operation. Follow-up ranged from 6 to 110 months (median 36 months). In 16 cases, simple endarterectomy with or without vein patch closure was performed (type I). In two cases the ostium of the ICA was occluded with interrupted sutures after endarterectomy (type II). In the remaining seven cases the ICA was transposed as a patch over the endarterectomized ECA after endarterectomy (type III). All but six patients (six sides) underwent duplex scanning or angiography during follow-up. Four of nine patients with previous nonlateralizing symptoms had persistent symptoms after operation, whereas none of those with previous amaurosis fugax did. Recurrent occlusive disease was more common in type I reconstructions (p less than 0.05). Proper ECA reconstruction results in long-term patency. In the patient with ipsilateral ICA occlusion, transposition of the ICA as a patch over the endarterectomized ECA offers a valid hemodynamic solution. Objective parameters are needed to identify patients with nonlateralizing symptoms who will benefit from operation.

Summary Dermal necrosis at various time-low temperature relationships has been determined in vivo and is presented graphically. There is need for better means of recognizing thermally degraded collagen microscopically.

Retroperitoneal descending thoracic aorta-femoral artery bypass was performed in 18 patients over an 11-year period. The reconstruction was carried to both femoral arteries in 12 patients; in the other 6, only a single femoral artery was revascularized. The operative indication in Group 1 (3 patients) was infection of a previous aortoiliac reconstruction; in Group 2 (12 patients), occlusion of a previous aortoiliac reconstruction; and in Group 3 (3 patients), aortoiliac occlusive disease in which a direct transabdominal procedure was considered hazardous. Follow-up ranged from 6 months to 9 years (mean, 40 months). Cumulative patency rate was 96 ± 3.9% at 1 year and 85 ± 8.1% at 5 years. No alterations of serum creatinine and blood urea nitrogen values were recorded seven days and 6 months after operation. Retroperitoneal thoracic aorta-femoral artery bypass is a useful technique for accomplishing lower limb revascularization in patients in whom exposure or availability of the abdominal aorta poses a specific hazard.

Cross-linked bovine collagen treatment of double velour prosthesis has re cently been introduced to help the graft ingrowth and neointima development in high-porosity graft without any need of preclotting. The authors have im planted (end-to-end) a total of 18 double velour 6-mm grafts (length 6 cm) in the infrarenal aorta of 18 dogs (15-25 kg). Nine prostheses were treated with colla gen (DVC) and 9 were untreated (DV). Animals with both kinds of prosthesis were sacrificed 3, 7, 10, 14, 21, 30, 60, 120, and 360 days after the implant. Preclotting was required only in DV grafts even though both grafts had some porosity (1,900 cc/min/cm2). Organization of the neointima of both grafts was studied and compared by light and scanning electron microscopy. DVC grafts showed an earlier (3-10 days) deposition of neoendothelial cells and a signifi cantly thicker neointima development within the first week from graft implant (p < 0.02). No statistical differences were noted in later neoendothelialization. Both grafts had a multifocal neoendothelial surface development around the neovasa vasorum in longer survival (days 21-360) whereas the ingrowth started from anastomoses in the early survival (days 3-14). In conclusion, DVC grafts, owing to the collagen treatment, do not require any preclotting despite their high porosity (equal to DV) and successfully accel erate short-term neointima development (> DV).

• In patients with combined aortoiliac and femoropopliteal occlusive disease, severe involvement of the deep femoral artery (DFA) has often been considered an indication for simultaneous aortofemoral and femorodistal bypass grafting. In 73 patients (87 limbs) with multilevel disease, extended DFA reconstruction was performed with aortofemoral bypass. Five-year actuarial patency of the reconstructions and overall five-year actuarial limb salvage were 62.2% and 60.2%, respectively. Of 20 variables tested, four were significantly associated with the functional outcome of the procedures. Multivariate analysis identified two factors as predictive of outcome independently from other variables: preoperative ankle-brachial pressure index and angiographic status of the below-knee popliteal artery. However, in case of reoperation for occluded aortofemoral graft, these factors lost their validity. Extended DFA reconstruction is a valuable and durable procedure able to provide an adequate outflow and distal perfusion. Careful judgment in each clinical situation will aid in selecting a small group of patients in which simultaneous femorodistal bypass is required. (Arch Surg1988;123:1269-1273)

A new device has been developed that is capable of processing information from a standard Doppler signal on the relative section (RS) of arteries during the cardiac cycle. RS is a new parameter proportional to the vessel cross-section and its changes during the cardiac cycle. This parameter does not give any morphologic information on the vessel itself, but it can help in completing Dop pler analysis, providing information on vessel elasticity. RS radius (R) and ve locity (V) (traditional Doppler) signals were routinely recorded under constant-pressure conditions. The device was tested in vivo by recording the R and V tracings on 20 common femoral arteries (cf) in dogs. These measure ments were compared with the R and V tracings obtained from the largest femoral branch (fb). R and V tracings were also obtained on 20 femoral arteries after surgically induced stenosis (above, at, and below the stenosis). Both exper iments showed a significant depression of the R tracings (p < 0.01). No signifi cant difference was found between the radius value and three-projection angiography of the stenosis (p=ns). The ability of the device to determine the elasticity of the arterial wall was evaluated in vitro on 10 specimens of athero sclerotic human tibial arteries, obtained from amputated lower extremities, and on 10 samples of dog femoral arteries, and the evaluations were compared. A significant difference in the radius root mean square values was found between the 2 groups (p < 0.01). The authors conclude that this device is capable of determining a new parameter (RS) that is proportional to the cross-section of the examined artery. They have also demonstrated that RS provides useful in formation about arterial wall elasticity.

To evaluate the efficacy of LDH isoenzymes in the detection of myocardial infarction in patients undergoing coronary bypass surgery, 73 patients were studied pre- and postoperatively by ECG, CPK, SGOT, total serum LDH, and LDH isoenzyme measurements. A reversal of the LDH1:LDH2 ratio was considered indicative of myocardial necrosis. Accordingly, the patients were separated into two groups: Group A (23 patients) who demonstrated an LDH1:LDH2 ratio exceeding 1.0 and Group B (50 patients) who failed to reveal an LDH1;LDH2 reversal. The two groups were similar in regard to preoperative evaluation and operative procedure performed. The postoperative ECG findings were significantly different. In Group A 18 of 23 patients (78 per cent) developed significant new Q waves. This occurred in only one patient in Group B. Significant arrhythmias occurred in 70 per cent of the patients in Group A as compared to 14 per cent of those patients in Group B. Severe congestive heart failure and/or clinical evidence of shock occurred in 39 per cent of Group A patients and in none in Group B. The results of our study indicate that the reversal of the LDH1:LDH2 ratio is a valuable tool for the evaluation of postoperative myocardial infarction.

Routine use of high-quality suture material has often been described as a factor in preventing complications such as false aneurysms, infection, and me chanical failure of implanted gafts. Optimal characteristics for a vascular su ture are to maintain its strength without causing an important "foreign body" reaction. Polypropylene monofilament has both characteristics and successfully replaced braided sutures for many years. A new monofilament suture material, which is made of expanded polytetrafluoroethylene (EPTFE), has recently been introduced. The purpose of the present study was to evaluate this new vascular suture and compare it with the widely and successfully used polypropylene su ture. The authors implanted a total of 20 infrarenal aortic reconstructions in dogs using both sutures to perform each anastomosis. Two dogs were sacrificed after 3, 7, 10, 14, 21, 30, 60, 120, 285, and 360 days. Light and scanning electron microscopy of the anastomotic site was routinely performed in order to compare the two suture materials. Thickness of inflam matory reaction around the sutures was measured at three different sites of each suture and statistically compared. Inflammatory reaction was minimal for both sutures and no significant difference was noticed by use of the Student's T- test (p=NS). No ingrowth was shown in either suture. EPTFE, in contrast to polypropylene, at scan electron microscopy, showed a nice layer of fibrin sur rounding the suture and a tendency to adapt to mechanical stress by being oval, elliptical, or circular. In the authors' opinion, EPTFE suture is, therefore, a valuable alternative for use in cardiovascular surgery.

A case of postsurgical constrictive calcific pericarditis is reported. The unusual features of this case are the short interval (two months) from surgery to the development of pericarditis and the involvement of the coronary arterial grafts, resulting in tearing of the vessels and the death of the patient during decortication.

The purpose of this study was to determine the factors influencing enlargement rate of small abdominal aortic aneurysms. Fifty-seven high-risk patients with asymptomatic abdominal aortic aneurysms initially measuring 3.5 to 5.9 cm in the largest transverse diameter were followed with serial echographic measurements for 6 to 78 months (mean 24). The mean enlargement rate (MER) and the occurrence of sudden change in size (SCS) for each aneurysm were correlated to 23 variables. MER ranged from 0 to 1.8 cm/year (mean 0.48). During the study period 17 aneurysms showed SCS. The results of univariate analysis indicated that 8 variables were statistically correlated to the degree of MER and 5 to the occurrence of SCS. A multiple regression model was generated by stepwise regression analysis and demonstrated that 2 variables were independent predictors of the degree of MER: (1) the absence of distal arterial occlusive disease and (2) the ratio of the diameter of the aneurysm to that of the aorta (RD). The overall model P value was less than 0.001. A statistically valid multiple regression model to predict the occurrence of SCS was not feasible (P = 1.0). We conclude that the occurrence of SCS of small abdominal aortic aneurysms is often unpredictable and that the RD rather than the value of the aneurysmal diameter per se must be considered in selecting high-risk patients for echographic follow-up.

Segments of an experimental polytetrafluoroethylene graft (9 cm long, 6 mm I.D.) of high porosity were implanted in 25 dogs as aortic interposition grafts. Nine grafts were seeded with a mean of 7 x 10(5) viable endothelial cells (ECs) derived from the jugular vein (group A) and eight were seeded with a mean of 7 x 10(5) viable ECs derived from the microvessels of the omentum (group B). Eight grafts were not seeded and they served as controls (group C). Animals were put to death 5 weeks after graft implantation. The thrombus-free area was measured at 81% +/- 10% in group A, 65% +/- 22% in group B, and 25% +/- 13% in group C (p less than 0.05, group A vs group B; p less than 0.05, group B vs group C). The thickness of the subendothelial layer was 151 +/- 60 microns in group A, 280 +/- 60 microns in group B, and 100 +/- 75 microns in group C (p less than 0.001, group B vs groups A and C). The production of 6-keto-PGF1 alpha in the presence of sodium arachidonate was higher in seeded grafts (p less than 0.05). Omentally derived microvessel ECs can be seeded in vascular grafts; refinements in the technique of EC procurement are required to minimize contamination and to obtain ECs with more effective biologic activity.

An experience on the surgical treatment of anastomotic false aneurysms during the last 15 years was reviewed. Fifty-nine were femoral anastomoses complicated by false aneurysm appearance requiring surgical excision. They represented 2.9% of all femoral anastomoses performed, whereas they represented 3.3% when considering reconstruction in which the femoral artery was the distal anastomosis. Reconstructions with distal anastomosis performed on the femoral artery were primarily involved (58 of 59), whereas grafts with "take off" from the femoral artery were rarely affected (p less than 0.05). A higher incidence of false aneurysm formation was demonstrated in hypertensive patients (p less than 0.05) as well as those who previously had femoral thromboendarterectomy (p less than 0.01). Infection was considered a causative factor even if it developed before (6-14 months) false aneurysm appearance. When a false aneurysm was resected, the best hemodynamic reconstruction, to avoid recurrence, was considered a bypass with distal anastomosis performed end-to-end on the femoral artery (p less than 0.05). The surgical treatment of choice was false aneurysm resection and graft interposition. However, a reanastomosis in the presence of small false aneurysms, when technically possible, has been successfully performed. Both treatments allowed good long-term results.

A ten-year review of 1,360 patients undergoing coronary artery bypass grafting (CABG) by the same surgeon was undertaken. Sixty-two patients with symptoms of coronary artery insufficiency underwent carotid endarterectomy prior to or at the time of CABG (Group I). Ninety-seven patients had asymptomatic carotid bruits but did not undergo carotid endarterectomy (Group II). Sixty of these patients were studied by ultrasonic duplex scanning or ocular pneumoplethysmography or both, and hemodynamically significant stenosis was detected in 50 (Group IIa). Group III included 80 patients without carotid artery disease matched with Group II for sex, age, and clinical status. Group IV consisted of 200 patients without carotid artery disease randomly selected from our series. Follow-up ranged from 3 to 120 months (median, 41 months). In patients with proven carotid artery disease (Groups I and IIa), operative mortality was greater than in the patients randomly selected (Group IV) (p less than 0.05) but similar to that in the matched Group III. Late neurological deficits were greater in patients with carotid disease not undergoing carotid endarterectomy (p less than 0.01). Patients with carotid artery disease had lower survival than Group IV patients (p less than 0.01) but similar survival to that in the matched Group III. This study suggests that (1) asymptomatic patients with carotid artery disease who undergo CABG are not at increased risk of perioperative stroke; (2) these same patients are at increased risk of late neurological deficit; and (3) carotid artery disease is an indirect sign of severe associated disease and therefore is associated with increased operative mortality and decreased life expectancy.

To determine the clinical characteristics and factors influencing outcome in patients with atherosclerotic abdominal aortic aneurysms (AAA), 526 patients who underwent aneurysmal resection were retrospectively reviewed: Group I had clinical evidence of atherosclerotic occlusive disease; Group II had no evidence of atherosclerotic occlusive disease. The incidence of ruptured AAA, multiple aneurysms, and a family history of AAA was higher in Group II patients. We concluded that patients with AAA and without atherosclerotic occlusive disease in other areas represent a subgroup with peculiar clinical characteristics. In planning operative treatment and during the follow-up period, it should be kept in mind that Group II patients have a higher incidence of aneurysm rupture; the incidence of late pseudoaneurysm is higher; and there is a greater possibility of aneurysm in other arterial segments. It remains to be seen if the pathogenetic mechanism of AAA formation in Group II patients is different from that in Group I patients.

• A 62-year-old woman with multiple neurofibromas of the lung was found to have severe hypoxemia due to right-to-left shunting within the tumors. Pulmonary angiograms demonstrated that the major area of shunting was in a large tumor mass in the right lower lobe. Pathologically the neurofibromas were vascular with hyperplastic small arteries and arterioles and large dilated veins. Multiple pulmonary neurofibromas are rare; and, to our knowledge, never previously reported in association with pulmonary arteriovenous shunting. ( Arch Intern Med 1986;146:1618-1619)

Responses of Rocky Mountain National Park elk (Cervus canadensis) to human activities were quantified in autumn 1974 and winter-spring 1975. During autumn, numbers of elk seen, rates of bugling, times of arrival and departure of elk to and from meadows, and harem bulls' activities were analyzed for relationships with traffic volume and tourist activities. Results suggested small effects of traffic volume upon elk, but no trends were statistically significant. People approaching animals off roads usually caused elk to leave open areas. Harassing elk in 2 meadows on alternate weeks during winter and spring did not affect their distribution or observability on winter ranges. Elk made greater use of areas near roads as the winter-spring study progressed, suggesting slight avoidance of roads when forage was more abundant earlier in winter. Wintering elk often used a residential area at night when human encounters were minimal. During winter and spring, elk were approached significantly closer during darkness with artificial lights than during daylight. These elk, which experienced little or no hunting, were very visible and were disturbed little, if any, by normal on-road visitor activities. J. WILDL. MANAGE. 42(1):91-100 Elk are frequently seen during autumn, winter, and spring in Rocky Mountain National Park, Colorado, where visitors make special efforts to observe and photograph them. Effects of this increasing pastime on behavior and ultimately on the physical condition of elk in the Park are unknown. Objectives of this study were to quantify effects of human activity and intentional harassment upon observability, movements, and behavior of Park elk during the rutting period and when elk are concentrated on winter-spring ranges. Elk in Rocky Mountain National Park have increased since 49 were reintroduced in 1913-1914. By 1943, concern for effects on ranges stimulated initiation of direct population control. This program was discontinued in 1945 due to public disfavor (Guse 1966). Controlled hunting by Park staff was resumed in 1949 and continued until 1962 when increasing public disfavor again prompted a halt (Gill 1967). Reduction programs encouraged elk to migrate out of the Park and harassing actions kept the animals scattered, thereby alleviating range damage in concentration areas, at least near roads (Broman 1954). Elk were comparatively difficult to observe during the early and middle 1960's, apparently because they were accustomed to being fired upon within the Park during earlier controlled hunts. Elk on open meadows usually fled into surrounding forest if approached by a vehicle. Elk seemed more observable in 1975, though no data are available for comparison. The 1975 estimate of elk wintering in Rocky Mountain National Park was 600 to 700 animals (David Stevens, Park Biologist, personal communication). Most studies of effects of human disturbance on ungulates have involved hunted populations. Geist (1971) stated that, "Mammals learn to minimize encounters with humans if harassed enough, by reducing activity to areas, habitats and times of day where encounters with humans are minimal." He suggested that harassment led to increased energy expenditures and was most damaging when animals were in poor condition and (Geist 1970) when the disturbance was frequent and unpredictable. Others studying effects of human activity on ungulates have noted effects upon physical condition, disease and reproduction (Zigunov 1961, Bannikov et al. 1961) and upon behavior, distribution and habitat J. Wildl. Manage. 42(1):1978 91 This content downloaded from 207.46.13.148 on Sun, 11 Sep 2016 04:33:54 UTC All use subject to http://about.jstor.org/terms 92 ELK RESPONSE TO HUMANS * Schultz and Bailey use (Walther 1969, Dauphine and McClure 1974, Batcheler 1968, Moran 1973, Rost 1975, Ward 1973, Dorrance et al. 1975). This study was financed by the Denver Service Center, National Park Service contract CX2000-5-0012. We gratefully acknowledge the advice, assistance and cooperation of E. Starkey, M. Nyquist, D. Stevens, and others of the National Park Service; of T. Boardman, Statistics Lab, Colorado State University; R. Gard and C. Hibler, also faculty of Colorado State; and of E. Reed and G. Rost, then students at Colorado State University.