Ligation of superior mesenteric vein and portal to splenic vein anastomosis after superior mesenteric-portal vein confluence resection during pancreaticoduodenectomy - Case report.

UNLABELLED: 62 year old Caucasian female with pancreatic head mass abutting the superior mesenteric vein (SMV) presented with fine needle aspiration biopsy confirmed diagnosis of ductal adenocarcinoma. CT scan showed near complete obstruction of portal vein and large SMV collateral development. After 3 months of neoadjuvant therapy, her portal vein flow improved significantly, SMV collateral circulation was diminished. Pancreaticoduodenectomy (PD) and superior mesenteric portal vein (SMPV) confluence resection were performed; A saphenous vein interposition graft thrombosed immediately. The splenic vein remnant was distended and adjacent to the stump of the portal vein. Harvesting an internal jugular vein graft required extra time and using a synthetic graft posed a risk of graft thrombosis or infection. As a result, we chose to perform a direct anastomosis of the portal and splenic vein in a desperate situation. The anastomosis decompressed the mesenteric venous system, so we then ligated the SMV. The patient had an uneventful postoperative course, except transient ascites. She redeveloped ascites more than one year later. At that time a PET scan showed bilateral lung and right femur metastatic disease. She expired 15 months after PD. CONCLUSION: The lessons we learned are (1) Before SMPV confluence resection, internal jugular vein graft should be ready for reconstruction. (2) Synthetic graft is an alternative for internal jugular vein graft. (3) Direct portal vein to SMV anastomosis can be achieved by mobilizing liver. (4) It is possible that venous collaterals secondary to SMV tumor obstruction may have allowed this patient's post-operative survival.

Femoral artery complications after cardiac catheterization: a study of patient profile.

BACKGROUND: Femoral artery complications after cardiac catheterization range from simple events to severe complications requiring invasive techniques or surgery with significant economic costs. This study evaluated early femoral arterial complications from percutaneous arterial access during diagnostic and interventional cardiac catheterizations in an era of widespread use of closure devices and intense anticoagulation. METHODS: Patients undergoing percutaneous cardiac catheterization via the femoral artery between August 2005 and December 2005 were identified using an ICD-9 patient database. Forty-six data points were extracted by retrospective chart review, including demographics, comorbidities, type of anticoagulation, procedural details, and postprocedural complications. Univariable analysis and binary logistic regression were used to determine factors associated with complications. RESULTS: Eighty-two of 579 patients (14%) suffered complications. The most common complications were hematomas (51 patients, 10%) and active bleeding (14 patients, 2.4%). Closure devices were used in 470 patients. After multivariable correction, use of preprocedural (odds ratio [OR]=5.65, 95% confidence interval [CI] 2.58-12.3, p<0.001) and intraprocedural (OR=4.88, 95% CI 1.95-12.3, p<0.001) antithrombotic agents (antiplatelet and/or anticoagulants), intraprocedural clopidogrel (OR=2.98, 95% CI 1.21-7.30, p=0.017), and postprocedural heparin (OR=29.4, 95% CI 3.56-250, p=0.002) were associated with increased risk. Coronary artery disease was associated with increased risk (OR=11.1, 95% CI 4.78-25.6, p<0.001), while use of a closure device (OR=0.263, 95% CI 0.125-0.553, p<0.001), male gender (OR=0.421, 95% CI 0.220-0.805, p=0.009), and prior catheterization (OR=0.033, 95% CI 0.012-0.095, p<0.001) were protective. CONCLUSION: With increasing numbers of complex coronary endovascular procedures and widespread use of high-dose multidrug antithrombotic therapy, femoral artery injuries will continue to be a significant risk for patients. Postprocedural monitoring with a high level of suspicion and use of vascular closure devices in high-risk patients may decrease the incidence of femoral artery complications. The use of vascular closure devices after low-risk procedures in male patients or those with previous ipsilateral catheterization might not be warranted but needs further study.

Changes in inferior vena cava filter placement over the past decade at a large community-based academic health center.

OBJECTIVE: A significant increase in the frequency of inferior vena cava (IVC) filter placement at our large community-based academic health center led us to evaluate changes in indications, devices, and providers over the past decade. METHODS: A single-center retrospective review of all filter placements was performed comparing 76 patients in 1995 with 470 patients in 2005. Demographic data, provider data, filter type, and indications for placement were tabulated. Complications, follow-up evaluation, filter removal, and patient outcomes were examined. RESULTS: There was a greater than sixfold increase in the number of filters placed in 2005 vs 1995. There were no significant differences in patient demographics or the extent of venous thromboembolic (VTE) disease during this period except for an increase in median age. Filter placement by interventional radiologists remained approximately 50% of the total whereas placement by vascular/trauma surgeons increased to 24% and placement by cardiologists decreased to 29% (P < .001). In 2005, a smaller percentage of filters were placed for absolute indications, while filter placements for relative and prophylactic indications increased over the same time period, especially among cardiologists (P = .02). Potentially retrievable filters are increasingly being used for prophylaxis; however, only 2.4% were retrieved. An increasing number of filters were placed in patients with only infrapopliteal deep venous thrombosis (P = .07). A shift was seen to lower profile and removable filter types. Long-term patient follow-up showed little change in disease progression or in morbidity and mortality of filter insertion. CONCLUSIONS: Technological and practice pattern changes have led to an increase in filters inserted by vascular and trauma surgeons in the operating room and intensive care units. Increased diagnosis of VTE disease and newer low profile delivery systems in patients may also have contributed to the significant increase in filter placement. A shift in indications for placement from absolute toward relative indications and prophylaxis is evident over time and across providers, indicating the need for consensus development of appropriate criteria.

Contemporary outcomes for carotid endarterectomy at a large community-based academic health center.

The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Asymptomatic Carotid Atherosclerosis Study (ACAS) demonstrated the efficacy of carotid endarterectomy (CEA), but these studies were published 15 and 11 years ago, respectively. We hypothesized that present clinical results of CEA have improved compared with those reported by NASCET/ACAS. Every patient having CEA from January 1999 through December 2003 was reviewed as part of a continuous quality-assurance program. Patient demographics and risk factors were recorded; high-risk patients were identified using inclusion criteria for high-risk carotid stent trials. Primary end points recorded were all neurologic events, deaths, and myocardial infarctions (MIs). Outcomes were reported individually or as combined neurologic events and deaths (traditional NASCET/ACAS methodology) and, similar to recent carotid stent trials, individually, combined, and as a composite that included MI. A total of 1,927 CEAs were performed, 1,140 in men (59%) and 787 in women (41%). The average age was 72 +/- 9 years; 21% of patients were age 80 or older. Symptomatic patients accounted for 717 procedures (37%). Perioperative neurologic event, death, and MI occurred in 1.0%, 0.5%, and 1.3% of patients, respectively. The combined neurologic event and death rate was 1.3% (symptomatic = 1.8%, asymptomatic = 1.1%). High-risk patients comprised 54% of the cohort; the neurologic event and death rate for this group was 1.6%. The composite end point including MI was 3.4%. Severe coronary artery disease and prior ipsilateral CEA significantly correlated with a higher incidence of primary end point complications. In contemporary practice, the perioperative neurologic event rate is significantly less than reported in NASCET/ACAS. Perioperative death and MI rates were similar to those seen in NASCET/ACAS. Neurologic events and death rates were not different between high- and low-risk groups. These data may serve as a guide for the modern vascular specialist weighing open and endovascular options for treatment of carotid artery occlusive disease in both high- and low-risk patients.

Intentional coverage of a main renal artery during endovascular juxtarenal aortic aneurysm repair in symptomatic high-risk patients.

PURPOSE: To describe the efficacy and morbidity of intentionally covering a main renal artery during symptomatic juxtarenal endovascular aneurysm repair (EVAR). CASE REPORTS: Two patients with symptomatic juxtarenal abdominal aortic aneurysm (AAA) were felt to be at prohibitive risk for open repair. Each underwent EVAR with intentional coverage of 1 main renal artery to achieve adequate proximal hemostatic seal. One patient died at 24 months; the second is symptom-free at 10 months. Both aneurysms initially decreased in diameter. Both patients had increased serum creatinine and required increased therapy for hypertension, but neither required hemodialysis. Renal volume decreased 48.7% and 68.0%, respectively. CONCLUSION: Intentional coverage of a main renal artery during EVAR for a symptomatic juxtarenal aneurysm resulted in effective short-term AAA repair with no need for dialysis. Despite the increased requirement for antihypertensive medications and the observed decline in renal function, this technique provides an option for treatment of this difficult patient subset.

Diagnosis of total internal carotid occlusions with duplex ultrasound and ultrasound contrast.

It remains a significant technical challenge for duplex ultrasound to accurately differentiate between total and near total internal carotid artery (ICA) occlusions. We have evaluated the efficacy of an ultrasound contrast agent combined with improved imaging techniques in patients with suspected carotid artery occlusions. Patients identified by conventional duplex ultrasound between January and August 2003 as having a possible ICA occlusion were eligible for study. A 1 mL bolus of ultrasound contrast agent was injected into a 50 mL bag of normal saline and given intravenously at a rate of approximately 4-5 mL/minute. Ultrasound imaging and spectral Doppler analysis were done using tissue harmonic imaging for optimum contrast agent to soft tissue discrimination, or with the direct B-mode imaging of blood flow to maximize the brightness of the circulating contrast agent. Ten patients were identified, 6 men and four women with a mean age of 68.3 years. Nine suspected total ICA occlusions were unilateral and 1 was bilateral. Imaging with contrast agent confirmed occlusion of the ICA in 7 of 10 patients; 3 patients had near-total occlusion with flow detected in the distal ICA by spectral and color Doppler. All 3 of these near-total occlusions were ultimately confirmed by either conventional or magnetic resonance carotid angiography. The contrast agent was most beneficial in improving the detection of minimal flow beyond a severe stenosis and in evaluating flow dynamics in the presence of severely calcified plaque. We conclude that the use of an ultrasound contrast agent with newer duplex ultrasound imaging techniques can reliably distinguish total from near-total internal carotid artery occlusions. Future prospective studies should be able to define the efficacy of ultrasound contrast agents in improving the overall diagnostic accuracy of duplex ultrasound in technically difficult cases and in patients with complex peripheral vascular disease.

Size and location of thrombus in intact and ruptured abdominal aortic aneurysms.

PURPOSE: This study compared the volume and morphology of intraluminal thrombus (ILT) in intact and ruptured abdominal aortic aneurysms (AAAs). METHODS: ILT volume in 67 intact AAAs and in 31 ruptured AAAs was assessed by using computed tomography (CT) angiography to measure the major and minor diameter of the outer wall and lumen of AAA as outlined by contrast at multiple sites. ILT thrombus morphology was recorded by AutoCAD 2000 software. Four equidistant images traced from the CT scan were recorded along the length of AAA. Thrombus volume was categorized as anterior-eccentric if the calculated area of thrombus was greater anteriorly, posterior-eccentric if greater posteriorly, eccentric-equal if the difference between the anterior and posterior thrombus was

Lysyl oxidase expression in bronchogenic carcinoma.

BACKGROUND: Lysyl oxidase catalyzes a key step in the cross-linking of collagen and elastin in the extracellular matrix. Recent studies have documented differential lysyl oxidase expression in the stromal reaction to colon, breast, prostate, and lung cancer. The present study was undertaken to test the hypothesis that lysyl oxidase mRNA and protein expression decrease with advancing tumor stage in patients with bronchogenic carcinoma. METHODS: Tumor specimens were obtained from 17 patients undergoing resection for bronchogenic carcinoma. Real-time polymerase chain reaction was used to determine steady-state lysyl oxidase mRNA expression, and protein expression was qualitatively assessed by immunohistochemistry. RESULTS: Real-time polymerase chain reaction studies documented a 3.4-fold graded decrease in lysyl oxidase mRNA levels as tumors progressed from stage I to IV. Similar qualitative changes in lysyl oxidase protein expression were demonstrated by immunohistochemistry. CONCLUSIONS: These results support the hypothesis that variations in lysyl oxidase expression may correlate with the invasive and metastatic potential of bronchogenic carcinoma.

Nitric oxide-releasing biopolymers inhibit thrombus formation in a sheep model of arteriovenous bridge grafts.

OBJECTIVES: Nitric oxide (NO), produced by normal vascular endothelial cells, reduces platelet aggregation and thrombus formation. NO-releasing biopolymers have the potential to prolong vascular graft and stent patency without adverse systemic vasodilation. METHODS: 5-mm polyurethane vascular grafts coated with a polymer containing the NO-donor dialkylhexanediamine diazeniumdiolate were implanted for 21 days in a sheep arteriovenous bridge-graft model. RESULTS: Eighty percent (4/5) of grafts coated with the NO-releasing polymer remained patent through the 21 day implantation period, compared to fifty percent (2/4) of sham-coated grafts and no (0/3) uncoated grafts. Thrombus-free surface area (+/-SEM) of explanted grafts was significantly increased in NO-donor coated grafts (98.2% +/- 0.9%) compared with sham-coated (79.2% +/- 8.6%) and uncoated (47.2% +/- 5.4%) grafts ( P = .00046). Examination of the graft surface showed no adherent thrombus or platelets and no inflammatory cell infiltration in NO-donor coated grafts, while control grafts showed adherent complex surface thrombus consisting of red blood cells in an amorphous fibrin matrix, as well as significant red blood cell and inflammatory cell infiltration into the graft wall. CONCLUSION: In this study we determined that local NO release from the luminal surface of prosthetic vascular grafts can reduce thrombus formation and prolong patency in a model of prosthetic arteriovenous bridge grafts in adult sheep. These findings may translate into improved function and improved primary patency rates in small-diameter prosthetic vascular grafts.

Duplex ultrasound recognition of spontaneous carotid dissection--a case report and review of the literature.

Spontaneous dissection of the internal carotid artery is an uncommon entity with a variable clinical presentation. A high index of suspicion is required to make the diagnosis, and prompt diagnosis and treatment with anticoagulation are essential for improved patient outcomes. Duplex ultrasound provides a safe and reliable imaging modality for early diagnosis and follow-up. The authors present a case of spontaneous internal carotid artery dissection with duplex ultrasound findings and a review of the literature.

Lysyl oxidase expression in a rat model of arterial balloon injury.

OBJECTIVE: Traditional therapies for arteriosclerotic disease often fail as a result of an exaggerated fibroproliferative response (recurrent stenosis) at the site of the intervention. Lysyl oxidase, secreted by activated vascular smooth muscle cells and fibroblasts, catalyzes a key step in the cross-linking and stabilization of collagen and elastin in the vascular wall. We hypothesized that lysyl oxidase messenger RNA (mRNA) and protein expression are time-dependent and precede collagen accumulation and luminal narrowing after arterial balloon injury in the rat. METHODS: A 2F balloon-tipped catheter was used to injure the right common carotid artery in male Sprague-Dawley rats. Injured right and control (uninjured) left common carotid arteries were harvested at 0, 0.25, 1, 3, 7, 14, 21, 28, and 60 days for mRNA quantitation and immunohistochemical analysis. Steady-state lysyl oxidase mRNA levels were quantitated with real-time reverse transcription polymerase chain reaction (TaqMan). Immunohistochemical staining with antibodies to alpha-smooth muscle cell actin and lysyl oxidase, and Movat pentachrome staining were performed for qualitative assessment of changes in the cellular and extracellular matrix components of the vessel wall. Post-injury intimal area was measured from hematoxylin and eosin-stained specimens at each time point. RESULTS: When compared with sham-operated control arteries, lysyl oxidase expression in balloon-injured arteries increased significantly to 212% by day 3 after injury, and remained elevated through day 21, with a decrease toward baseline levels by day 28. Lysyl oxidase protein expression did not peak until day 14, and persisted through day 28. Collagen accumulation peaked at day 28, corresponding to the maximal increase in intimal area, with later accumulation of proteoglycans and ground substance in the intimal lesion. CONCLUSION: Our results indicate that lysyl oxidase mRNA and protein expression is time-dependent after balloon injury of the rat carotid artery and that expression appears to precede maximal collagen accumulation and corresponding increases in intimal area. This suggests that lysyl oxidase may have an important role in stabilization of collagen and elastin at sites of vascular injury and that modulation of lysyl oxidase activity may be a viable method to prevent or reduce recurrent stenosis. CLINICAL RELEVANCE: Failure of traditional therapies for ischemic arteriosclerotic disease is often due to an exaggerated fibroproliferative response (recurrent stenosis) at the site of intervention. Recurrent stenosis can be viewed as an injury-repair process, with an initial stage characterized by cellular proliferation followed by deposition of extracellular matrix. This study focuses on lysyl oxidase, a key enzyme involved in stabilization of collagen and elastin. This study demonstrates that lysyl oxidase messenger RNA and protein expression are time-dependent, preceding collagen accumulation and corresponding increases in intimal area. Accumulation of extracellular matrix is a major factor in growth of the restenotic lesion, and modulation of lysyl oxidase activity may offer a therapeutic method for decreasing or preventing recurrent stenosis.

Gastrointestinal complications following infrarenal endovascular aneurysm repair.

Gastrointestinal complications are known to occur after open elective aortic aneurysm repair. This leads to increased morbidity, mortality, length of stay, and hospital costs. The authors hypothesize a change in the character and/or frequency of early postoperative gastrointestinal complications after endovascular aneurysm repair as compared to open abdominal aortic repair. This is a retrospective cohort study in which the medical records of 153 consecutive patients who underwent endovascular infrarenal aneurysm repair from November 1998 to August 2001 were reviewed for gastrointestinal complications. Of these 153 patients, 9 (5.9%) had postoperative gastrointestinal complications. Three patients (1.9%) underwent exploratory laparotomy for small bowel obstruction. One patient had had a right hemicolectomy for cancer 2 years before stent graft placement. This patient needed a partial small bowel resection. One patient had had a right hemicolectomy 4 months before stent graft placement; he had lysis of adhesions with no bowel resection. A third patient underwent operative repair of an incarcerated inguinal hernia. Six patients (3.9%) had paralytic ileus that was treated by nasogastric tube or observation resulting in an extended hospital length of stay. All cases of ileus resolved without any operative intervention. No patients in this series developed any intestinal ischemia, pancreatitis, cholecystitis, or gastrointestinal bleeding. After endovascular aneurysm repair, gastrointestinal complications such as ileus and postoperative small bowel obstruction are seen with a similar frequency as after open aortic repair. This occurs despite the absence of a laparotomy with mesenteric dissection and evisceration. In this series, these complications are associated with longer hospital length of stay but no increased mortality rate. No instances of colonic ischemia, pancreatitis, cholecystitis, or gastrointestinal bleeding were seen in this series.

Hypothermia is an independent predictor of mortality in ruptured abdominal aortic aneurysms.

Hypothermia is known to significantly increase mortality in trauma patients, but the effect of hypothermia on outcomes in ruptured abdominal aortic aneurysms (RAAA) has not been evaluated. The authors reviewed their experience from 1990 to 1999 in 100 consecutive patients who presented with RAAA and survived at least to the operating room for surgical treatment. There were 70 men and 30 women, with a mean overall age of 74 +/-8 years. Overall mortality was 47%. Univariate ANOVA (analysis of variants) showed significant correlation with mortality for decreased intraoperative temperature, decreased intraoperative systolic blood pressure, increased intraoperative base deficit, increased blood volume transfused, increased crystalloid volume (all p < 0.001); decreased preoperative hemoglobin (p = 0.015); and increased age (p = 0.026). Patient sex, initial preoperative temperature, preoperative systolic blood pressure, and operating room time were not correlated with mortality in the univariate analysis. Using these same clinical variables, multiple logistic regression analysis showed only 2 factors independently correlated with mortality: lowest intraoperative temperature (p = 0.006) and intraoperative base deficit (p = 0.009). The mean lowest temperature for survivors was 35 +/-1 degrees C and for nonsurvivors 33 +/-2 degrees C (p < 0.001). When patients were grouped by lowest intraoperative temperature, those whose temperature was < 32 degrees C (n = 15) had a mortality rate of 91%, whereas patients with a temperature between 32 and 35 degrees C (n = 50) had a mortality rate of 60%. In the group that remained at or > 35 degrees C (n = 35) the mortality rate was only 9%. A nomogram of predicted mortality versus temperature was constructed from these data and showed that for temperatures of 36, 34, and 32 degrees C the predicted mortality was 15%, 49%, and 84%, respectively. The authors conclude that hypothermia is a strong independent contributor to mortality in patients with ruptured abdominal aortic aneurysms and that very aggressive measures to prevent hypothermia are warranted during the resuscitation and treatment of these patients.

Reliability of extracranial carotid artery duplex ultrasound scanning: value of vascular laboratory accreditation.

OBJECTIVES: The purpose of this study was to evaluate the reliability of carotid duplex ultrasound scanning performed by nonaccredited vascular laboratories and to assess the clinical effect on patient management. METHODS: We retrospectively reviewed concordance of findings of carotid duplex ultrasound scanning between laboratories accredited by the Intersocietal Commission for Accreditation of Vascular Laboratories and nonaccredited laboratories in 174 patients with asymptomatic disease referred to tertiary care community hospitals for surgical evaluation for carotid endarterectomy (CEA) between January 2001 and December 2002, and evaluated changes in clinical management made on the basis of repeat examinations. RESULTS: Concordant findings were noted in 171 of 348 arteries (49%), predominantly those with minimal or mild disease (114 arteries; 67%). Discordant findings of no clinical significance were found in 54 arteries (16%). Clinically significant discordant findings were noted in 123 arteries (35%) in 107 patients (61%). In 104 arteries (88 patients) stenosis was overestimated by the nonaccredited laboratory secondary to technical error (19 arteries), use of B-mode imaging data alone (36 arteries), and use of inappropriate velocity criteria (49 arteries). None of these patients underwent CEA. Stenosis was significantly underestimated in 19 arteries (19 patients); all of these patients underwent uncomplicated CEA. CONCLUSIONS: Incorrect physician interpretation of data is the most common cause of error in carotid duplex ultrasound scanning performed in nonaccredited vascular laboratories. Results of carotid duplex ultrasound scanning from nonaccredited laboratories should be considered with extreme caution, and do not appear reliable in planning treatment of obstructive disease.

Duplex ultrasound imaging with an ultrasound contrast agent: the economic alternative to CT angiography for aortic stent graft surveillance.

The use of endovascular stent graft repair for aortic aneurysmal disease has become increasingly common, with the added requirement for close postoperative surveillance to detect the presence of endoleaks or graft migration. The most commonly used technique for surveillance is computed tomography (CT) angiography, with the need for intravenous contrast posing 1 limitation in those patients with renal dysfunction and the cost of this testing presenting an economic limitation. Early results of duplex imaging in the authors' Vascular Laboratory using an intravenous ultrasound contrast agent have shown sensitivity and specificity equivalent to those of CT angiography, with no evidence of any related morbidity. They have evaluated the cost effectiveness of using duplex ultrasound imaging as the primary surveillance technique for postoperative follow-up in aortic stent graft patients. Surveillance protocols now require that 8 follow-up examinations be performed in the first 3 years after stent graft placement. The charges for CT angiography in their institution average 2,779 dollars per study, for a 3-year total of 22,232 dollars per patient. The charges for aortic duplex ultrasound average 525 dollars per study, with a 3-year total of 4,200 dollars per patient. Adding the cost of routine abdominal radiographs to confirm stent graft position (147 dollars per study) would bring this 3-year total to 5,376 dollars, a savings of 16,856 dollars per patient. For every 100 patients who are followed up after stent graft placement, this represents a 3-year savings of more than 1.6M dollars. Promising early results of duplex ultrasound imaging with an intravenous contrast agent show sensitivity and specificity equivalent to those of CT angiography in detecting aneurysm size and graft endoleaks or other hemodynamic abnormalities. If these results can be demonstrated in larger patient series, this technique should become the method of choice for stent graft surveillance, for it offers very significant economic advantages and avoids the complications of intravenous contrast-induced renal dysfunction.

Transrenal fixation of endovascular stent-grafts for infrarenal aortic aneurysm repair: mid-term results.

PURPOSE: We evaluated mid-term results of a single-center consecutive series of endovascular stent-grafts implanted for aortic aneurysm repair with transrenal fixation, to determine clinical outcome, aneurysm anatomy, renal artery patency, and renal complications. METHODS: Modular stent-grafts were placed with transrenal fixation in 37 patients between November 1998 and July 2000. Follow-up evaluation included clinical examination, laboratory evaluation of serum creatine concentration, computed tomographic angiography, and renal duplex scanning. RESULTS: Thirty-seven patients underwent transrenal fixation of aortic stent-grafts as part of a Phase II US Food and Drug Administration study. Two patients subsequently underwent follow-up at institutions closer to their homes, and thus provided clinical information but no long-term renal or aneurysm morphologic data. There were no perioperative deaths. Five patients died during follow-up, at a mean of 9 months, because of myocardial infarction in 4 patients and respiratory failure in 1 patient. Thirty patients, ages 75 +/- 8 years, have been followed up for 28.5 +/- 7.2 months. Aneurysm diameter at follow-up was 5.0 +/- 0.8 cm, compared with 5.7 +/- 0.8 cm preoperatively. In 5 patients, endoleak developed during follow-up: 1 type I leak was treated with an aortic cuff, with temporary stabilization of the aneurysm and correction of the endoleak; 2 type II endoleaks were treated with translumbar coil embolization, and 1 resolved spontaneously; and 1 type III endoleak was treated with a combination of coil embolization and stent-graft extension to cover a graft defect. Preoperatively, serum creatinine concentration was normal in 23 patients, but increased persistently in 2 patients and was abnormal in 7 patients. Postoperatively, creatine concentration increased in 4 patients to greater than 20% of baseline level. Seventeen patients had no evidence of renal artery stenosis, compared with 13 patients with renal artery stenosis. Of 41 normal renal arteries, 90% remained unchanged, 1 became occluded, 3 demonstrated 60% stenosis. Nephrectomy was necessary in 1 patient because of cancer. Of 19 abnormal renal arteries, progression of disease was noted in 3 arteries. CONCLUSIONS: Transrenal fixation of aortic stent-grafts can be performed with acceptable mid-term outcome with respect to mortality, need for follow-up intervention, and aneurysm exclusion with protection from rupture. Postprocedural stenosis can develop in both normal and abnormal renal arteries. Rate of progression of disease was greater in patients with preprocedural renal dysfunction compared with patients with normal renal arteries. This is merely an observation, and may not be related to transrenal fixation. Long-term follow up is needed.

Relationship of residual intraluminal to intrathrombotic pressure in a closed aneurysmal sac.

PURPOSE: This study was undertaken to determine the relationship of residual intraluminal aneurysmal sac pressure (ILASP) to intrathrombic aneurysm sac pressure (ITASP) and to define the relationship between abdominal aorta aneurysm (AAA) size (anteroposterior or transverse diameter), volume of intraluminal thrombus, and residual ITASP. METHODS: We measured ILASP and ITASP after proximal aortic neck and distal iliac clamping by placing angiocatheters into the lumen and thrombus of an excluded aneurysm sac in 41 consecutive patients. Simultaneously, mean blood pressure was recorded and aneurysm sac pressure ratio was calculated. Changes in ILASP and ITASP after clamping of the inferior mesenteric artery were recorded. In addition, correlation between AAA size, volume of intraluminal thrombus in AAA, and residual ITASP was determined. RESULTS: Mean ILASP/blood pressure ratio was 0.40 (SD, 0.20). Mean ITASP/blood pressure ratio was 0.37 (SD, 0.23). There was a significant positive correlation of 0.47 between ITASP and ILASP (P =.002). Clamping of the inferior mesenteric artery resulted in markedly decreased ITASP in 2 patients (n = 40) and ILASP in 4 patients (n = 41). Each centimeter increase in AAA size resulted in a 47 mL increase in thrombus volume. CONCLUSION: Increased ILASP results in corresponding increase in ITASP, and increased AAA size is associated with increased thrombus volume. However, neither thrombus volume nor AAA size has any relationship to ITASP.

Efficacy of ultrasound scan contrast agents in the noninvasive follow-up of aortic stent grafts.

OBJECTIVE: Computed tomographic angiography (CTA) is currently the most commonly used technique for postoperative surveillance to detect endoleaks after endovascular stent graft repair of abdominal aortic aneurysms. We have evaluated the efficacy of duplex ultrasound scan with the addition of an ultrasound scan contrast agent in documenting endoleaks and compared these results with CTA. METHODS: Conventional duplex ultrasound scan with color Doppler imaging (CDI) was first done as part of routine postoperative surveillance. After the CDI study, a 1-mL bolus of ultrasound scan contrast was given via an antecubital vein, followed by a 5-mL flush with normal saline solution. The duplex ultrasound scan evaluation of the stent graft was repeated once the contrast agent was circulating throughout the blood pool, with tissue harmonic imaging to optimize visualization of the contrast agent. Status of the stent graft, the presence or absence of any endoleak, and whether these endoleaks were graft related (group I) or arterial branch related (group II) were recorded. Findings were compared with CTA studies done within a 2-week period of the ultrasound scan examination. RESULTS: Twenty patients were evaluated, 18 with modular stent grafts and two with unibody bifurcated stent grafts. Patients had a mean age of 74.5 +/- 7.6 years; 19 were male, with only one female. All stent grafts remained widely patent with normal aortoiliac flow hemodynamics. Duplex ultrasound scan with contrast identified all eight of the endoleaks seen with CTA and was able to determine whether they were group I or group II leaks. In two patients, ultrasound scan with contrast detected small endoleaks at the proximal graft attachment site, with extravasation of contrast into the aneurysm sac during systole. These endoleaks were not seen with CTA but were confirmed with conventional angiography at the time of endovascular closure. Standard duplex ultrasound scan with CDI failed to identify four of the 10 endoleaks in patients with technically difficult conditions. CONCLUSION: Duplex ultrasound scan, when used with an intravenously administered ultrasound scan contrast agent in the noninvasive follow-up of patients with aortic stent grafts, appears to provide good sensitivity to the presence and type of endoleaks, even in patients with technically difficult conditions not amenable to conventional duplex ultrasound scan with CDI.

Simultaneous stent-graft repair of thoracic and infrarenal abdominal aortic aneurysms.

PURPOSE: To describe a technique for concomitant endovascular stent-graft repair of thoracic and infrarenal abdominal aortic aneurysms. CASE REPORT: A 68-year-old man was found to have concomitant thoracic and abdominal aortic aneurysms. Both of the aneurysms were excluded successfully in one procedure using Talent stent-grafts. The patient tolerated the procedure well and was discharged on postoperative day 4. Aside from an infected groin wound, the patient did not have any complications. Computed tomographic scans at 6, 12, and 18 months showed proper position of both stents without evidence of endoleak. CONCLUSIONS: Simultaneous endovascular treatment of thoracic and infrarenal abdominal aortic aneurysms may represent a viable alternative for therapy in some patients.