The juxtarenal abdominal aortic aneurysm. A more common problem than previously realized?

OBJECTIVE: To determine the incidence and treatment outcome of juxtarenal infrarenal aneurysmectomy in a vascular practice minimally biased by tertiary referral. DESIGN: A 5-year retrospective review of all aortic operations from our vascular registry was performed, and a case series of juxtarenal aneurysmectomies was analyzed. PATIENTS: Of 174 infrarenal aortic aneurysmectomies performed, 27 (15.5%) (95% confidence interval, 10.5% to 21.8%) involved the juxtarenal aorta. INTERVENTIONS: Juxtarenal involvement was unsuspected but found by aortography in 25 (93%) of 27 cases. Resection was performed transabdominally in 20 cases (74%) and retroperitoneally in seven cases (26%). MAIN OUTCOME MEASURES: Incidence, operative technique, morbidity, and mortality were analyzed and compared with those of historical controls. RESULTS: The incidence of juxtarenal aneurysmectomy was 15.5%. No operative deaths occurred, but there was a 19% incidence of surgical morbidity (including a 7% incidence of transient renal failure). The late survival rate was 89% (follow-up, 1 to 53 months; mean, 18 months). CONCLUSIONS: Juxtarenal aortic aneurysms are not uncommon. Successful management is possible, even outside the large referral center.

The retroperitoneal, left flank approach to the supraceliac aorta for difficult and repeat aortic reconstructions.

Between 1986 and 1990, 11 patients with relative or absolute contraindications to standard infrarenal reconstructions underwent supraceliac aortofemoral bypass. The operation was performed through a left-flank incision extended into the eleventh intercostal space with retroperitoneal and extrapleural dissection. Indications included multiple failed infrarenal reconstructions in four patients, previous removal of infected aortofemoral bypass graft with failure of extra-anatomic bypass in five patients, prior para-aortic lymph node dissection and radiotherapy in one patient, and aortic aneurysmal disease proximal to the renal arteries in one patient. Bypass conduits included either a bifurcated Dacron graft or a tube graft to the left femoral artery with a femorofemoral cross-over graft; concomitant left renal artery reconstruction was performed in three patients. The mean supraceliac cross-clamp time was 24 minutes, and only one patient experienced transient postoperative acute tubular necrosis. There was no operative mortality. The graft limb patency was 95% after mean follow-up extending to 17 months (range: 5 months to 5 years). We conclude that the supraceliac aorta is a useful inflow source for aortofemoral reconstruction in difficult repeat cases. It can be approached easily without thoracotomy and avoids difficult infrarenal aortic dissection in a scarred field. The tunneling is easier than with descending thoracic aorta or ascending aorta inflow sources. In addition, this bypass is likely to be more durable than inflow reconstructions based on the axillary artery.

Contribution of routine intraoperative completion arteriography to early infrainguinal bypass patency.

To determine the clinical utility of routine intraoperative completion arteriography, we prospectively evaluated 214 consecutive infrainguinal bypass grafts (209 reversed-vein and 5 polytetrafluoroethylene grafts) performed from July 1987 to August 1991. Visual inspection, pulse palpation, and continuous-wave Doppler examination were performed in all cases. At least 1 completion arteriogram was obtained in 213 cases (99%). The bypasses were to the popliteal artery in 130 cases and to the tibial or pedal arteries in 84 cases. Graft patency was confirmed at 30 days in all patients by ankle-brachial index determinations (greater than 0.2 increase) and duplex scan-derived peak-systolic flow velocities (greater than 45 cm/s). Significant technical problems requiring revision were identified in 18 grafts (8%), including 6% of popliteal grafts and 12% of tibial/pedal grafts. Only three of these problems were suspected by pulse palpation or continuous-wave Doppler examination. The intraoperative angiographic findings leading to revision included distal anastomotic stenoses (n = 6), distal arterial disease requiring sequential bypass (n = 4), mid-graft valvular or branch ligature stenoses (n = 4), distal arterial thrombosis (n = 2), and graft kink or twist (n = 2). Thirty-day primary patency was 99% (129 of 130) for femoropopliteal grafts and 93% (78 of 84) for femorodistal grafts. Secondary patency was 100% (130 of 130) and 96% (81 of 84), respectively. Primary patency was 89% (16 of 18) for those grafts that required intraoperative revision based on arteriographic findings. We conclude that routine completion arteriography is an excellent method of ensuring the intraoperative technical adequacy of infrainguinal bypass. The test is easy to perform, reproducible, and should be considered the "gold standard" for intraoperative bypass assessment. Prior to adopting angioscopy or duplex scanning for intraoperative surveillance, randomized, controlled validation studies against angiography should be performed.

The utility and durability of vein bypass grafts originating from the popliteal artery for limb salvage.

BACKGROUND: Short vein grafts originating from sites distal to the common femoral artery have been reported to be useful in selected patients with tibial artery disease. From 1987 to 1993, we performed 504 consecutive infrainguinal vein bypass grafts, of which 56 (11%) originated from the popliteal artery, 25 above and 31 below the knee. PATIENTS AND METHODS: The patients were 16 women and 37 men, with a mean age of 62.4 years. Eighty-seven percent were diabetic, 57% had clinically obvious coronary artery disease, and 28% had end-stage renal disease (ESRD). The indication for surgery was ulceration or gangrene in 93% of cases. We preferentially used reversed greater saphenous vein harvested from the thigh to optimize conduit quality and avoid lower leg wound complications. The outflow artery sites were: dorsal pedal (17), posterior tibial (14), peroneal (10), anterior tibial (8), lateral or medial plantar (5), and sequential tibial (2). All patients were followed postoperatively with serial duplex surveillance. The mean follow-up was 12.5 months (range 1 to 66). RESULTS: In-hospital mortality was 5.4%. Mortality at 24 months was 19% overall and 38% in patients with ESRD. Limb salvage was 77% at 3 years, 92% in patients with normal renal function versus 59% in those with ESRD (P < 0.003). Primary graft patency by life-table analysis was 94% at 1 month and 84% at 3 years. Five patients with patent grafts required amputation, 4 early and 1 late. Eight months after surgery, 1 patient (1.8%) developed superficial femoral artery stenosis which was diagnosed by duplex surveillance and successfully treated by percutaneous transluminal balloon angioplasty. CONCLUSIONS: Vein bypass grafts originating from the popliteal artery are effective and durable. Proximal disease progression rarely poses a significant threat to long-term graft patency. Patients with ESRD, blind tibial outflow tracts, and extensive forefoot lesions appear to be at increased risk of limb loss even with continued graft patency.

Does infrapopliteal arterial runoff predict success for popliteal artery aneurysmorrhaphy?

BACKGROUND: A 6-year experience with surgical management of popliteal artery aneurysms (PAAs) was examined to determine the influence of infrapopliteal outflow vessel patency on the long-term success of popliteal artery aneurysmorrhaphy. METHODS: Arteriograms were reviewed to characterize the anatomy of the infrapopliteal arterial runoff. Regular clinical evaluation and prospective serial duplex scan surveillance assessed graft patency. RESULTS: A total of 28 patients underwent 45 popliteal aneurysmorrhaphies. Elective repair was performed in 32 limbs (71%); emergency treatment was needed for 13 limbs (29%) because of acute limb-threatening ischemia. All patients were managed with PAA exclusion and reversed saphenous vein grafting. Only 20 limbs (44%) had a patent trifurcation with three continuous vessels to the ankle, 13 (29%) had two continuous tibial vessels, 10 (22%) had one patent runoff artery, and 2 (4%) had no vessel continuous to the foot. With a mean follow-up of 19.1 months, the 5-year primary graft patency by life-table analysis was 95 +/- 12.3%, with a 5-year assisted primary patency of 97 +/- 10.0%. One vein graft underwent elective secondary revision. Another graft thrombosed, requiring a secondary bypass. Outcome did not correlate with the status of the runoff anatomy. Limb salvage was 100%. CONCLUSION: The use of autologous reversed vein grafting and attention to technical details yielded normal graft hemodynamics and excellent long-term patency and limb salvage despite the suboptimal runoff anatomy associated with PAAs.

Revision of the failing vein graft: outcome of secondary operations.

Infrainguinal vein bypass continues to be widely accepted as providing effective palliation for disabling claudication and limb salvage in patients with arterial insufficiency of the lower extremity. The development of lesions that may threaten vein graft patency are presently an inevitable consequence of arterial reconstruction in the atherosclerotic patient. However, long-term patency has been sustained by detection and intervention for inflow, outflow, or intrinsic graft lesions. The excellent secondary (assisted primary) patency rates achieved for both reversed and in situ vein grafts affirm the importance of a noninvasive surveillance protocol and a low threshold for reintervention before actual graft failure.

Surgical methods for renal revascularization.

The availability of newer treatment alternatives for patients with renovascular disease has resulted in many patients being referred for surgical intervention in a delayed fashion. As a result of these changes in the type of patients being referred to surgery with more advanced renovascular hypertension and renal excretory dysfunction, vascular surgeons need to be well versed in the variety of surgical renal revascularization techniques. Each of the procedures has its own advocates, but many of these techniques are not applicable in all patients. Familiarity with the various techniques allows the surgeon to have a choice in the method of renal revascularization appropriate for a given clinical situation. Ultimately, the efficacy of any interventional procedure must be considered along with its associated morbidity, mortality, and long-term clinical outcome. All become important factors when considering the optimal primary surgical procedure to treat the patient with renovascular hypertension or renal excretory dysfunction.

Screening and preoperative imaging of candidates for carotid endarterectomy.

Randomized clinical trials have provided us with clinical guidelines regarding the indications for performing carotid endarterectomy in patients who have symptomatic and asymptomatic disease. Logically, any patient with a history of transient ischemic attacks, amaurosis fugax, or stroke should be evaluated for extracranial carotid artery occlusive disease. In asymptomatic patients, however, carotid artery surveillance may be helpful in identifying those at risk before neurological events. Patients at particularly high risk include those identified with (1) manifestations of systemic atherosclerotic disease (peripheral vascular disease, coronary artery disease, renovascular disease); (2) presence of a carotid bruit; (3) advanced age (> 65 years); and (4) ABI less than 0.7. Duplex ultrasonography remains the best and most widely used noninvasive screening method, but its accuracy is highly technologist dependent. A high-quality duplex study may, in itself, be adequate to determine whether the severity of extracranial carotid occlusive disease warrants surgical intervention. Catheter-based arteriography may be used as an adjunct to validate duplex results, but its invasive nature and risk of complications has popularized alternative imaging methods. Of these, magnetic resonance angiography (MRA) and spiral computed tomographic angiography (CTA) show excellent promise as noninvasive imaging techniques for the evaluation of extracranial carotid artery occlusive disease.

Preoperative splenic artery occlusion as an adjunct for high risk splenectomy.

High risk splenectomy is often encountered in cases of hypersplenism with massive splenomegaly (10 times usual weight of 150-200 g) resulting from myelophthisic processes. Intra-operative ligation of the splenic artery through the lesser sac is a technically useful method of gaining vascular control prior to mobilizing the challenging spleen. However, a massive or inaccessible spleen imposes mechanical limitations during surgery and may be complicated by torrential intra-operative hemorrhage in the setting of severe thrombocytopenia refractile to platelet transfusions. The authors describe pre-operative intravascular proximal splenic artery control in four adult patients (3 men, 1 woman) with extreme splenomegaly (2,250-10,000 g). The massive splenomegaly in this group resulted from chronic myelogenous leukemia (n = 2), isolated splenic lymphoma (n = 1), and agnogenic myeloid metaplasia (n = 1). Chief symptom manifestations included left upper quadrant abdominal pain, early satiety, post-prandial emesis, dyspnea, petechiae, and associated easy bruising. Prior to surgery, all the patients were taken to the radiology suite where either detachable silastic balloons or stainless steel coils were placed selectively into the splenic artery under fluoroscopic guidance requiring approximately 35 minutes. Splenic artery occlusion aided normalization of thrombocytopenia (average increases 19,000/microliter to 215,000/microliter) with prolongation in survival of platelets. Successful splenectomy was subsequently performed with no additional transfusion requirements and was made technically easier by reducing splenic bulk. There were no adverse consequences of intravascular occlusion and no peri-operative morbidity or mortality. Preoperative intravascular selective splenic artery occlusion, used as an important potential adjunct to anticipated high risk splenectomy, is recommended.(ABSTRACT TRUNCATED AT 250 WORDS)

Thermal studies of in-vivo vascular tissue fusion by argon laser.

There are conflicting opinions regarding the mechanism of welding or fusion of vascular tissue by lasers. In this study, we measured the effects of saline irrigation on tissue temperature and fusion produced by argon laser welding of eight femoral and four carotid arteriovenous fistulas. Temperatures were continuously recorded using a digital thermographic camera. Forty 1-cm. welds were performed using powers of 0.50 (n = 24), 0.75 (n = 8), and 1.00 (n = 8) watt (W), with an energy fluence of 1100 J/cm2 per 1 cm segment, and cooling of the anastomotic site by saline irrigation (3 ml/minute). The "success" of fusions was determined by testing integrity of the repairs by exposure to blood flow. At 0.50 and 0.75 W, successful welds were formed when the temperatures were 44.2 +/- 1.6 (n = 28) and 55.0 +/- 3.6 degrees C (n = 20), with maximum temperatures of 47.9 and 59.9 degrees C respectively. At 1 W, the tissue was desiccated and the welds disrupted when exposed to blood flow with temperatures measured at 63.7 +/- 10.0 degrees C (n = 22) and maximum of 88.0 degrees C. Eight welds were also attempted without saline irrigation at 0.25 (n = 4) and 0.50 W (n = 4). At 0.25 W, tissue fusion was achieved but disrupted when exposed to intraluminal pressures with temperatures 50.3 +/- 2.0 degrees C (n = 10) and maximum of 52.6 degrees C. At 0.50 W, the fusion failed after only minimal exposure to the laser energy because of tissue drying and retraction with temperatures measured at greater than 125 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Canine peripheral vascular arteriosclerosis following myointimal fragmentation and atherogenic diet.

The development of arteriosclerotic peripheral vascular lesions following balloon catheter and mechanical fragmentation of the arterial myointima combined with an atherogenic diet was studied in a canine model. The ileofemoral arteries of five mongrel dogs (mean wt 22 +/- 2 kg) were selectively cannulated and subjected to balloon catheter and mechanical myointimal injury by repeated longitudinal and transverse shearing forces. Twenty grams of hydrogenated coconut oil and a 5.0% cholesterol diet were fed to the animals daily during the study period. Followup angiographic studies obtained at 4 weeks (n = 2), 10 weeks (n = 3), 16 weeks (n = 3), and 24 weeks (n = 2) demonstrated changes of progressive peripheral vascular occlusion. Concurrent duplex Doppler studies correlated well with the angiographic results. At 10 (n = 1), 18 (n = 2), and 24 (n = 2) weeks, the animals were sacrificed and the vessels were perfusion-fixed in situ with 2% glutaraldehyde or formaldehyde solutions and excised. Histological examination demonstrated extensive arteriosclerotic changes including (i) fragmentation and reduplication of the internal elastic membrane, (ii) myointimal hyperplasia with fibroblastic proliferation including the development of fibrous intimal plaques, and (iii) transmigration and proliferation of smooth muscle cells with scattered monohistiocytes. The specimens showed a range of stenotic changes from 25% to total occlusion of the vascular lumen. These preliminary data demonstrate the feasibility of providing intense arteriosclerotic myointimal histologic changes in the canine peripheral vasculature within a 24-week period. Further refinement of this methodology may provide a practical model for studies of localized peripheral vascular occlusive disease.

Vascular grafts in head and neck reconstructive surgery.

The best management of advanced head and neck tumors invading the carotid artery utilizes a collaborative, anticipatory approach. Preoperative characterization of the anatomy and extent of tumor involvement, coupled with the physiologic assessment of the cerebrovascular circulation through the variety of adjunctive studies, facilitates operative planning. Careful preoperative evaluation allows the surgeon to make the most informed decision regarding extracranial carotid artery reconstruction, should carotid artery resection be required for adequate tumor removal. When the preoperative evaluation indicates that adequate cerebral perfusion or collateral reserve will not be maintained with carotid artery occlusion, carotid artery reconstruction needs to accompany any resection of this vessel. Autogenous saphenous vein remains the graft conduit of choice, but prosthetic materials may be used. Graft patency and healing require appropriate concomitant soft-tissue coverage of any overlying mucosal or cutaneous defects.

Challenges of hemodialysis access for high risk patients: Impact of mesenteric vein bioprosthetic graft.

OBJECTIVE: The purpose of this study is to compare in a prospective fashion the performance of a new bioprosthesis, the mesenteric vein bioprosthesis (MVB), in patients who have had multiple failed ePTFE grafts. Performance measures include primary patency rates, assisted-primary patency rates, secondary patency rates, complications, and the number of interventions required to maintain graft patency. STUDY: From October 1999 to February 2002, 276 hemodialysis access grafts were implanted in a multicenter study. Of those grafts, 74 were placed in patients with a prior history of 3 failed prosthetic grafts (mean = 3.5 grafts, range = 3-6 grafts). Fifty-nine grafts were constructed with MVB, and 15 grafts with ePTFE as a concomitant control. Mean follow-up was 11.5 months. In the MVB group, 79.7% were African-Americans, 61% were females, and 23.7% were hypercoagulable. Of the ePTFE group, 86.7% were African-Americans, 46.7% were female, and 13.2% were hypercoagulable. Results : Per Kaplan-Meier curves, the primary patency rate of the MVB group at 12 months was 33% vs the ePTFE group of 18% (p=0.120); the assisted-primary patency rates at 12 months were 45% MVB vs 18% ePTFE (p=0.011). The secondary patency rates at 12 and 24 months for the MVB group were 67% and 59%, respectively, vs 45% and 15% for the ePTFE group (p=0.006). During the follow-up time period, 80% of the ePTFE grafts were abandoned compared to 34% of the MVB group. Infection and thrombosis rates in the MVB group were lower than the ePTFE group. The infection rate for the MVB group requiring intervention was 0.07 events/graft year (gt/y) compared to 0.30 events/gt-y for ePTFE (p=0.04). A thrombosis rate of 0.69 events/gt-y occurred in the MVB group whereas 2.50 events/gt-y presented in the ePTFE group (p<0.01). CONCLUSION: In this study, high-risk patients (defined as those having multiple failed prosthetic grafts for hemodialysis) in whom the MVB conduit for hemoaccess was implanted, showed significant improvement in assisted-primary and secondary patency rates compared to the ePTFE cohort. The MVB group, however, did not have a statistically better primary patency rate compared to the ePTFE group. The MVB patient also had fewer thrombotic and infectious events and an overall reduction in the number of interventions while maintaining a permanent access site. This new bioprosthesis should be the conduit of choice in the complex group of patients as it offers assisted-primary and secondary patency rates similar to those commonly experienced by patients without a history of multiple graft failures.

The "blue-toe" syndrome as a harbinger of impending infrainguinal vein graft failure: a report of three cases.

Spontaneous "blue-toe" syndrome classically results from distal lower extremity microembolization of intraluminal atheromatous debris from a proximal source to the digital end arteries. During a 6-year period, 274 consecutive infrainguinal reversed vein arterial reconstructions were performed; in three patients (1.1% incidence), atypical distal microembolization originating from focal preocclusive intraluminal vein graft stenoses was identified. Sudden, spontaneous onset of ipsilateral blue-toe syndrome occurred at intervals of 4 to 11 months. Subsequent duplex scans and arteriography demonstrated patent grafts with high-grade, hemodynamically significant focal proximal short-segment sclerotic vein graft stenosis (n = 1) and midgraft valvular weblike stenoses (n = 2) with luminal irregularity. No other associated tandem lesions in the proximal or distal arterial tree were noted that would account for the microembolic phenomenon. The stenotic vein segments were excised with interposition vein graft replacement (n = 1) or with primary end-to-end reanastomoses (n = 2), resulting in complete resolution of the distal microembolic events without need for amputation. Histologic examination of these graft lesions demonstrated significant focal myointimal hyperplasia with adherent platelet aggregates and organized thrombus. The clinical presentation of distal lower extremity cutaneous digital ischemia consistent with microembolization developing ipsilateral to a previously placed vein conduit arterial bypass may signify a "failing" graft with a source from a preocclusive lesion. This finding should prompt aggressive evaluation and immediate revision to maintain assisted primary graft patency and prevention of tissue loss.

The role of the deep femoral artery as an inflow site for infrainguinal revascularization.

PURPOSE: Although the deep femoral artery (DFA) is well acknowledged as an outflow vessel for inflow reconstruction, data are lacking concerning the suitability of the DFA as an inflow site for distal bypass. METHODS: From 1986 to 1992 we performed 268 consecutive infrainguinal reversed vein bypasses, of which 56 (21%) originated from the middle or distal DFA. The indications for DFA-origin grafts included inadequate vein length, need for concomitant extended profundaplasty, and avoidance of groin scarring from previous reconstruction or infection. The surgical approach to the DFA (standard, posteromedial, or lateral) was tailored to the patient. All grafts were monitored with serial duplex scanning surveillance. RESULTS: Primary and secondary patency rates of DFA origin grafts were 78% and 96% at 3 years. These patency rates were no different from those grafts originating from the common femoral artery (66%; 89%), the superficial femoral artery (69%; 87%), or the popliteal artery (66%; 87%). Hemodynamic failure was detected in seven DFA-origin grafts, but only one resulted from disease in the common femoral artery or DFA proximal to the origin of the vein graft. CONCLUSIONS: Direct lateral and posteromedial approaches to the DFA were used extensively in repeat operative situations, avoiding dissection in a scarred groin and shortening the length of vein required to perform an autogenous bypass. We conclude that in appropriately selected patients, the DFA origin technique increases the versatility of lower extremity vein bypass grafting without sacrificing durability.

Preoperative testing before carotid endarterectomy: a survey of vascular surgeons' attitudes.

Traditional surgical practice and published consensus statements from major vascular surgery specialty societies have considered contrast arteriography to be a routine part of the diagnostic evaluation prior to carotid endarterectomy (CEA). However, some surgeons now omit routine preoperative arteriography if a technically adequate carotid duplex scan is performed and indications for CEA are clear. To better establish current practice patterns and to characterize vascular surgeons' opinions about the role of preoperative arteriography, the Peripheral Vascular Surgery Society membership was surveyed by mail. Eighty-six percent of the members responded (430 of 502). Ninety-three percent of all patients considered for CEA are evaluated with duplex scanning; 82% with arteriography. While the majority of surgeons typically obtain both a duplex scan and an arteriogram, 70% have performed CEA without a preoperative arteriogram. Brain imaging studies (CT or MRI) are obtained in 26% and MR angiograms in 10% of cases. Seventy-five percent of the surgeons agreed with the statement that CEA without preoperative arteriography is an acceptable practice if appropriate indications for surgery are present. Furthermore, one third believed that CEA without a preoperative arteriogram is generally acceptable (acceptable more than half the time). Respondents were stratified by surgical experience time in practice and practice type. No significant differences in responses were found, suggesting the acceptance of CEA without preoperative arteriography is broad-based. This survey demonstrates changing attitudes among practicing vascular surgeons regarding the necessity for routine arteriography prior to CEA. Carotid endarterectomy on the basis of duplex scanning and clinical assessment should be considered an accepted alternative.

The characteristics and anatomic distribution of lesions that cause reversed vein graft failure: a five-year prospective study.

PURPOSE: The cause of vein graft failure in the intermediate postoperative period (3 to 18 months) has not been well defined. To delineate the incidence, characteristics, and anatomic distribution of lesions that cause graft failure in this critical interval, 227 consecutive infrainguinal reversed vein grafts (IRVGs) constructed at a single institution from July 1986 to December 1991 were prospectively entered into a duplex scan surveillance protocol. METHODS: Duplex surveillance with arteriographic confirmation identified 29 patent, hemodynamically failing IRVGs during a mean follow-up of 22 months (range 1 to 64 months). An additional 18 grafts thrombosed before detection of any underlying abnormality; thrombolytic therapy and repeat operation uncovered the cause of occlusion in 12 of these grafts. The cause of graft failure (failing as well as failed) was therefore clear in 41 (87.2%) of 47 instances. RESULTS: The causes of failure were intrinsic graft stenosis (n = 28; 59.6%), inflow failure (n = 6; 12.8%), outflow failure (n = 4; 8.5%), muscle entrapment (n = 2; 4.3%), and hypercoagulable state (n = 2; 4.3%). The most common intrinsic graft lesion was focal intimal hyperplasia (18 lesions in 16 grafts) in the juxtaanastomotic position, occurring solely in the vein graft itself. It occurred with equal frequency immediately distal to the proximal anastomosis or proximal to the distal anastomosis. Only rarely (n = 5) did this involve the juxtaanastomotic artery. Focal midgraft valvular stenoses (n = 6) and diffuse myointimal hyperplasia (n = 4) were also detected. The peak incidence of graft failure was 4 to 12 months after operation (70% within 12 months, 80% within 18 months). CONCLUSIONS: We conclude that duplex surveillance of IRVGs is warranted by the 21% incidence of potentially remediable graft failure. A significant portion of these failures occur during the intermediate postoperative period (3 to 18 months), usually as a result of focal intrinsic vein graft lesions. With reversed vein conduits, these lesions arise predominantly in the vein graft itself, in the juxtaanastomotic position.

Perioperative suppression of platelet adherence to small-diameter polytetrafluoroethylene (PTFE) grafts.

The perioperative effect of platelet antagonists on small-diameter polytetrafluoroethylene (PTFE) grafts was evaluated in forty-six New Zealand white male rabbits receiving either dipyridamole (DPM) 100 mg/kg/day (n = 10; group 1), aspirin (ASA) 10 mg/kg/day (n = 10; group 2), a combination of ASA 10 mg/kg/day and DPM 10 mg/kg/day (n = 9; group 3) or 100 mg/kg/day (n = 10; group 4), or placebo (n = 7) as single daily doses. All regimens began 72 hr prior to insertion of a 20 x 3-mm internal diameter PTFE interposition aortic graft. Autologous indium-111 labeled platelets were injected immediately after implantation. Graft and an equivalent segment of aorta were harvested after 48 hr. Graft platelet adherence index (GPAI) was calculated as the graft:reference aorta ratio of emissions. The GPAI in the control group was 238 +/- 46 (mean +/- SD). Single regimen antiplatelet agents in groups 1 and 2 reduced mean GPAI to 47 +/- 38 and 40 +/- 12, respectively. The combination regimen in group 3 lowered mean GPAI to 43 +/- 8 and in group 4 to 21 +/- 7. Platelet uptake in PTFE grafts at 48 hr is significantly lowered to 8.8 to 19.7% of control by perioperative antiplatelet agents given as a single daily oral dose (P less than 0.001). ASA alone and DPM alone provided similar suppression of platelet uptake, but combination ASA + low dose or high dose DPM gave significantly greater (P less than 0.001) suppression of early platelet deposition than the single agent regimens. These results support perioperative administration of combination oral antiplatelet agents as adjunctive therapy in small diameter prosthetic graft implantation.

Combined coronary artery bypass and abdominal aortic aneurysmectomy: appropriate management in selected cases.

Patients with aortic aneurysms frequently have concomitant coronary artery disease, which carries the potential for significantly increased perioperative morbidity. Most cases of severe surgically correctable coronary artery disease can and should be treated by a separate operation before aneurysmectomy to lower operative cardiac morbidity and enhance long-term survival. Infrequently, a patient can have both unstable coronary disease and a large symptomatic aortic aneurysm. In this situation, a single procedure combining coronary artery bypass followed by aneurysmectomy, as illustrated by this case report, is a reasonable option and should be considered in the cases of carefully selected patients.