Cardiac varix presenting as a right atrial mass.

A cardiac varix is an unusual tumor of vascular origin that is rarely discovered antemortem. Here, we report the incidental finding of this lesion in the right atrium of a patient with concomitant prostate cancer.

The creation of an infrarenal aneurysm within the native abdominal aorta of swine.

BACKGROUND: Models of native abdominal aortic aneurysms (AAA) have been created in rodents using elastase and calcium chloride perfusion. These models, however, do not permit the evaluation of endovascular devices. This study describes the use of mechanical and enzymatic techniques to create native AAA in swine. METHODS: Surgically exposed abdominal aortas of ten male Yorkshire swine (25-35 kg) were dilated, then perfused for 20 min with a 50-mL solution of elastase (30 units) and collagenase (8000 units). Serial magnetic resonance imaging (MRI) at 1, 3, and 6 wk was used to evaluate postoperative aortic diameter. Animals were euthanized at 24 h, 48 h and 1, 2, and 6 wk for histological evaluation. RESULTS: MRI demonstrated an increase in mean aortic diameter by 73.3% +/- 30.2% (33.3-116.7%), which gradually increased postoperatively. Partial endothelial loss, mural neutrophil infiltrate, and elastin disruption were evident (1, 3, and 7 days). Smooth muscle cell attrition occurred within the inner tunica media (7 days). Collagen deposition, limited SMC repopulation and luminal reendothelialization appeared at 3-6 wk. Elastin injury persisted. CONCLUSIONS: The creation of an infrarenal aneurysm is possible within the native aorta of swine. After aneurysm creation, progressive increase in aortic diameter was detectable. Further evaluation will be necessary to more completely characterize the nature and extent of elastase-induced porcine aortic aneurysmal degeneration.

Characterization of endoleak following endovascular repair of abdominal aortic aneurysms.

Aneurysm models have been developed to study the pathobiology of abdominal aortic aneurysm and to evaluate the efficacy of endovascular therapy. The purpose of this review is to describe the use and limitations of current animal and experimental models for the characterization of endoleak following endovascular repair of abdominal aortic aneurysms.

Safety and efficacy of carotid angioplasty and stenting in high-risk patients.

Performance of carotid endarterectomy (CEA) may be associated with an increased risk in patients with significant comorbid medical conditions, neck irradiation, or previous CEA. This study compared the results of CEA with carotid angioplasty and stenting (CAS) in high-risk patients treated for carotid stenosis. Five hundred forty-five patients who underwent CEA and 148 patients who underwent CAS were evaluated. For patients undergoing CEA, general anesthesia was used in 91 per cent, electroencephalographic monitoring was used in 63 per cent, and shunting was performed in 19.8 per cent. Cerebral protection devices were used in 145/148 of CAS cases, and self-expanding stents were used in all cases. Evaluated end points included major cardiovascular events, and a composite of death, stroke, or myocardial infarction for the duration of the follow-up. Mean follow-up was 18 months for CAS and 23 months for CEA. Significant differences were present in patient age (CAS, 75 +/- 11.0 years vs CEA, 71 +/- 9 years, P = 0.012), however, there were no significant differences (P = NS) in gender or smoking history. The mean modified Goldman Score was significantly higher for CAS (21.1 +/- 14.8 [95% confidence interval = 18, 24]) than for CEA (6.3 +/- 6.8 [95% confidence interval = 5.7, 6.9]; P = 0.0001) patients. The incidence of periprocedural complications did not vary significantly between patients treated with CAS (CVA, 1.4%; myocardial infarction [MI], 1.4%; death, 0.7%; CVA/MI/death, 3.4%) compared with CEA (CVA, 1.8%; MI, 1.1%; death, 0.4%; CVA/MI/death, 4.0%). CAS is equivalent to CEA in safety and efficacy, even when performed in patients who may be at increased surgical risk.

Do bone marrow micrometastases correlate with sentinel lymph node metastases in breast cancer patients?

BACKGROUND: Sentinel lymph node biopsies (SLNB) are used to detect axillary metastases as an important prognostic indicator for breast cancer patients. Bone marrow micrometastases (BMM) have also been shown to predict prognosis. This study examines whether SLNB and BMM are associated. STUDY DESIGN: A retrospective analysis was performed on 124 stages I to III breast cancer patients treated with mastectomy or lumpectomy, SLNB, and bone marrow aspiration between 1997 and 2003. SLNB were examined for the presence of metastases by hematoxylin and eosin (H&E) stains and also by immunohistochemistry (IHC) for lymph nodes negative by H&E. The kappa statistic was used to evaluate the association (agreement) between SLNB and BMM. RESULTS: In this study population, 36 patients (29%) had micrometastases detected in their bone marrow, and 51 patients (41%) had positive sentinel lymph nodes. Of the patients with positive BMM (n = 36), 53% (19 of 36) had positive SLNB (14 of 19 by H&E and 5 of 19 by IHC). In patients with negative BMM (n = 88), 36% (32 of 88) had a positive SLNB (27 of 32 by H&E and 5 of 32 by IHC). The kappa statistic and associated 95% confidence interval indicated poor agreement between SLNB and BMM (kappa = 0.15; 95% CI = -0.03, 0.32). CONCLUSIONS: There was poor agreement between axillary metastases and micrometastases detected in the bone marrow. This study suggests that BMM and axillary metastases are not concordant findings in most patients.

Comparison of results in endovascular interventions for infrainguinal lesions: claudication versus critical limb ischemia.

This study analyzed clinical success, patency, and limb salvage after endovascular repair in patients treated for chronic limb ischemia presenting with claudication versus critical limb ischemia. Between October 2001 and August 2004, 115 patients (mean age 71) underwent endovascular treatment for infrainguinal arterial disease. Techniques included subintimal angioplasty and transluminal angioplasty with or without stents. Lesions were classified according to Transatlantic InterSociety Consensus. Follow-up (mean 11 months) included physical exam, ankle-brachial index, and duplex ultrasound. Patency rates were determined using Kaplan-Meier and compared by log-rank analysis. One hundred ninety-nine lesions were treated in 121 limbs using percutaneous techniques. Comorbidities were similar except higher rates of diabetes mellitus (67% vs 41%, P < 0.001) and chronic renal insufficiency (22% vs 7%, P < 0.05) were found in critical limb ischemia patients. Primary patency for claudicants was 100 per cent, 98 per cent, and 85 per cent at 3, 6, and 12 months and 89 per cent, 80 per cent, and 72 per cent for critical limb ischemia, respectively (P = 0.06). Limb salvage was 91 per cent at 12 months for critical limb ischemia patients. Morbidity was similar between groups, and there was no perioperative mortality. Percutaneous intervention for both claudication and critical limb ischemia provides acceptable 12 month patency with limited morbidity.

Embolization of renal artery aneurysm and arteriovenous fistula-a case report.

A renal artery aneurysm with an associated arteriovenous fistula in a native kidney has been reported infrequently in the literature. Management depends on size, location, and the patient's physiological condition. We describe a case in which endovascular therapy was used to successfully exclude both aneurysm and fistula. This report describes a 13-centimeter renal artery aneurysm with arteriovenous fistula originating from an isolated branch of the renal artery. Coil-embolization resulted in thrombosis of the aneurysm and fistula while preserving parenchymal perfusion. Coil embolization is an alternative to surgery for coexistent renal artery aneurysm and arteriovenous fistula arising from a branch of adequate length for placement of embolic coils. Successful treatment is not limited by aneurysm size or presence of arteriovenous connection.

Multimodal therapy for acute and chronic venous thrombotic and occlusive disease.

Critical deep venous thrombosis and occlusion constitutes a small percentage of patients with venous disease. However, these patients exhibit severe symptomatology including pain and extensive edema that may progress to limb- or life-threatening complications such as phlegmasia cerulea dolens and superior vena cava syndrome. This paper reviews the different multimodal percutaneous interventions currently available for the treatment of complex critical venous thrombotic and occlusive disease.

Gastrointestinal complications after mitral valve surgery.

INTRODUCTION: Gastrointestinal (GI) complications are well-recognized risks of open heart surgery. However, open heart surgery comes in different shapes and sizes with widely varying pre-operative, intra-operative and post-operative pathologies. The aim of this study was to examine the etiology and risk factors for GI complications after mitral valve surgery. METHODS: A retrospective analysis of 565 patients who underwent mitral valve surgery from 2003-2005 was performed. Prospectively collected data included preoperative risk factors, cardiac status, intra-operative data, postoperative GI complications and mortality. Survival was analyzed using log-rank analysis. RESULTS: In this study population, 13 patients (2.3%) had 16 GI complications after mitral valve surgery resulting in an overall mortality of 0.7%. Complications included GI bleed (n = 9), cholecystitis (n = 3), perforated diverticulitis (n = 1) and ischemic bowel (n = 3). By univariate analysis, a history of hypertension, chronic renal insufficiency (CRI), hypercholesterolemia, myocardial infarction, congestive heart failure, cardiogenic shock, emergency valve surgery, coronary artery bypass surgery and preoperative vasopressor use were each associated with an increased incidence of GI complications (p <0.05). No increased incidence was seen in patients with atrial fibrillation. On multivariate analysis adjusted for age, cardiogenic shock (OR 8.1; 95% CI, 1.9-34.8), CRI (OR 8.1; 95% CI, 2.2-30.0) and vasopressor use (OR 6.5; 95% CI, 1.3-31.0) remained significant (p <0.02). Mean survival (3.2 vs. 5.4 years) was significantly lower (p <0.05) in those with GI complications. CONCLUSIONS: GI complications after mitral valve surgery are infrequent, with a higher incidence in those with cardiogenic shock, CRI or requiring vasopressors. Pre-operative hemodynamic instability may be a bellwether for potential GI complications and should be of more prominent concern in this cohort of patients.

Innominate artery cannulation: an alternative to femoral or axillary cannulation for arterial inflow in proximal aortic surgery.

OBJECTIVE: To evaluate the effectiveness of innominate artery cannulation in proximal aortic procedures, including those involving hypothermic circulatory arrest. METHODS: A total of 68 patients underwent innominate artery cannulation with a side graft during proximal aortic surgery performed by way of a median sternotomy. The indications for surgery were proximal arch aneurysm in 43 patients (63.2%), aortic dissection in 11 patients (16.2%), total arch aneurysm in 10 patients (14.7%), and ascending aortic aneurysm in 4 patients (5.9%). Six patients (8.8%) had undergone previous sternotomy. Hypothermic circulatory arrest with antegrade cerebral perfusion was used in 64 patients (94.1%). Of the 68 patients, 63 (92.6%) received antegrade cerebral perfusion to both cerebral hemispheres. The median antegrade cerebral perfusion time was 20 minutes (range, 15.0-33.0 minutes). Seven patients had periods of circulatory arrest without antegrade cerebral perfusion for a median of 20 minutes (range, 6-33 minutes). RESULTS: One patient died, for 30-day mortality of 1.5%. Three patients (4.4%) had strokes, two of whom had a partial recovery. Seven patients (10.3%) developed temporary postoperative confusion that resolved successfully in all cases. CONCLUSIONS: Cannulating the innominate artery for arterial inflow is an alternative technique for proximal aortic surgery procedures. It is especially useful in cases requiring hypothermic circulatory arrest to deliver antegrade cerebral perfusion.

Ectopic liver: an unexpected finding in a right atrial mass.

Ectopic liver is a rare finding, particularly in intrathoracic locations. We report the case of a 42-year-old woman with a mobile right atrial mass that was subsequently identified as ectopic liver by histology. Its point of origin was in a hepatic vein with extension into the right atrium. Although accurate diagnosis of ectopic liver may be possible with advanced imaging techniques, limited familiarity with the clinical entity is a barrier to early diagnosis.

Ischemic preconditioning during the use of the PercuSurge occlusion balloon for carotid angioplasty and stenting.

Ischemic preconditioning (IP) uses transient ischemia to render tissues tolerant to subsequent, prolonged ischemia. This study sought to evaluate factors that contributed to the development of cerebral ischemia during PercuSurge balloon (Medtronic, Santa Rosa, CA) occlusion in patients undergoing carotid angioplasty and stenting (CAS). The PercuSurge occlusion balloon was used in 43 of 165 patients treated with CAS for high-grade stenosis; 20% were symptomatic. Symptoms of cerebral hypoperfusion during temporary occlusion of the internal carotid artery occurred in 10 of 43 patients and included dysarthria, agitation, decreased level of consciousness, and focal hemispheric deficit. The development of neurologic symptoms after initial PercuSurge balloon inflation and occluded internal carotid artery flow was associated with a decrease in the mean Glasgow Coma Scale (GCS) from 15 to 10 (range 9-14); the GCS returned to normal after occlusion balloon deflation. The mean time to spontaneous recovery of full neurologic function was 8 minutes (range 4-15 minutes). The mean subsequent procedure duration was 11.9 minutes (range 6-21 minutes). No recurrence of neurologic symptoms occurred when the occlusion balloon was reinflated. All 10 patients underwent successful CAS without occlusion, dissection, cerebrovascular accident, or death. Ischemic preconditioning can be used to enable CAS with embolic protection in patients who cannot tolerate initial interruption of antegrade cerebral perfusion by PercuSurge occlusion.

Reduced primary patency rate in diabetic patients after percutaneous intervention results from more frequent presentation with limb-threatening ischemia.

OBJECTIVE: Although patients with diabetes are at increased risk of amputation from peripheral vascular disease, excellent limb-salvage rates have been achieved with aggressive surgical revascularization. It is less clear whether patients with diabetes will fare as well as nondiabetics after undergoing percutaneous lower extremity revascularization, a modality which is becoming increasingly utilized for this disease process. This study aimed to assess differential outcomes in between diabetics and nondiabetics in lower extremity percutaneous interventions. METHODS: We retrospectively studied 291 patients with respect to patient variables, complications, and outcomes for percutaneous interventions performed for peripheral occlusive disease between 2002 and 2005. Tibial vessel run-off was assessed by angiography. Patency (assessed arterial duplex) was expressed by Kaplan-Meier method and log-rank analysis. Mean follow-up was 11.6 months (range 1 to 56 months). RESULTS: A total of 385 interventions for peripheral occlusive disease with claudication (52.2%), rest pain (16.4%), or tissue loss (31.4%) were analyzed, including 336 primary interventions and 49 reinterventions (mean patient age 73.9 years, 50.8% male). Comorbidities included diabetes mellitus (57.2%), chronic renal insufficiency (18.4%), hemodialysis (3.8%), hypertension (81.9%), hypercholesterolemia (57%), coronary artery disease (58%), tobacco use (63.2%). Diabetics were significantly more likely to be female (55.3% vs 40.8%), and suffer from CRI (23.5% vs 12.0%), a history of myocardial infarction (36.5% vs 18.0%), and

Abdominal aortic aneurysm in women: prevalence, risk factors, and implications for screening.

OBJECTIVE: Accurate data regarding the prevalence and associated risk factors for aneurysmal disease is essential when determining the appropriateness of screening for abdominal aortic aneurysms (AAA). Although women are poorly represented in most large studies of AAA prevalence, the US Preventative Services Task Force recently recommended against primary screening for AAA in women. The purpose of this analysis was to define the prevalence and risk factors associated with the development of AAA in women. METHODS: A free duplex ultrasound screening was offered to men and women with cardiovascular risk factors or a family history of AAA. Patients were recruited through advertising at local screening centers and screenings were performed between 2004 and 2006. Demographic information and cardiovascular and aneurysmal disease risk factors were obtained for each patient through a questionnaire. A total of 17,540 subjects were screened for AAA, including 10,012 women (mean age 69.6 years) and 7528 men (mean age 70.0 years). Univariate and multivariable logistic regression analysis was performed on the subset of women that were screened to determine risk factors for and prevalence of AAA. RESULTS: Seventy-four aneurysms were detected in women (including four aneurysms >5 cm diameter and 70 aneurysms 3 to 5 cm diameter) while 291 were detected in men, resulting in prevalence rates of 0.7% and 3.9%, respectively. Increasing age (odds ratio [OR]= 4.57, 95% confidence interval [CI] 1.98 to 10.54, P < .0001), history of tobacco use (OR = 3.29, 95% CI 1.86 to 5.80, P < .0001), and cardiovascular disease (OR= 3.57, 95% CI 2.19 to 5.84, P < .0001) were independently associated with AAA in women on univariate and multivariable analysis. Women with multiple atherosclerotic risk factors were more commonly found to have AAAs and had a prevalence rate of AAA as high as 6.4%. CONCLUSION: Although the medical literature suggests a low prevalence rate of AAA in women in the general population, specific risk factors are associated with the development of AAA, and subgroups of women can be identified that are at a substantially increased risk of aneurysmal disease. In particular, elevated rates of AAA were found among women of advanced age (> or =65 years) with a history of smoking or heart disease. These data support the notion that women with such risk factors should be considered for AAA screening.

Cerebral ischemia associated with PercuSurge balloon occlusion balloon during carotid stenting: Incidence and possible mechanisms.

BACKGROUND: Interruption of antegrade cerebral perfusion results in transient neurologic intolerance in some patients undergoing carotid angioplasty and stenting (CAS). This study sought to evaluate factors that contributed to the development of cerebral ischemia during PercuSurge balloon occlusion and techniques used to allow successful completion of the CAS procedure. METHODS: The PercuSurge occlusion balloon was used in 43 of 165 patients treated with CAS for high-grade stenosis (mean stenosis, 90%). All 43 patients were at increased risk for endarterectomy (7 restenosis, 3 irradiation, 3 contralateral occlusion, and 30 Goldman class II-III); 20% were symptomatic. Symptoms of cerebral hypoperfusion during temporary occlusion of the internal carotid artery occurred in 10 of 43 and included dysarthria (7/10), agitation (6/10), decreased level of consciousness (5/10), and focal hemispheric deficit (3/10). An incomplete circle of Willis or contralateral carotid artery occlusion, or both, was present in 8 of 10 patients. Symptoms resulting from PercuSurge balloon occlusion were managed by balloon deflation with or without evacuation of blood from the internal carotid artery using the Export catheter. All symptoms resolved completely without deficit after deflation of the occlusion balloon. RESULTS: The development of neurologic symptoms after initial PercuSurge balloon inflation and occluded internal carotid artery flow was associated with a decrease in the mean Glasgow Coma Scale (GCS) from 15 to 10 (range, 9 to 14); the GCS returned to normal after occlusion balloon deflation and remained normal during subsequent reinflation. The mean time to spontaneous recovery of full neurologic function was 8 minutes (range, 4 to 15 minutes). No thrombotic or embolic events were present on cerebral angiography or computed tomography scan. Balloon reinflation was performed after a mean reperfusion interval of 10 minutes after full neurologic recovery (range, 4 to 20 minutes). The mean subsequent procedure duration was 11.9 minutes (range, 6 to 21 minutes). No recurrence of neurologic symptoms occurred when the occlusion balloon was reinflated. All 10 patients underwent successful CAS without occlusion, dissection, cerebrovascular accident, or death. CONCLUSION: Several factors may contribute to the development of neurologic intolerance during CAS with balloon occlusion. Elucidation of the protective cellular mechanisms that invoke ischemic tolerance after the initial transient ischemic event may enable CAS with embolic protection in patients who cannot tolerate initial interruption of antegrade cerebral perfusion.

Evaluation of the accuracy of a wireless pressure sensor in a canine model of retrograde-collateral (type II) endoleak and correlation with histologic analysis.

BACKGROUND: The utility of intra-aneurysmal pressure determination is dependent on the ability to measure pressure in the presence of endoleak and thrombosis. In this study, the accuracy of a CardioMEMS wireless pressure sensor (CardioMEMS, Atlanta, Ga) transducer in the presence of thrombus associated with type II endoleak was measured. METHODS: Type II endoleaks were created in four mongrel dogs by implanting four collateral arterial side branches (lumbar and caudal mesenteric arteries) as a Carrel patch onto a 3-cm prosthetic polytetrafluoroethylene abdominal aortic aneurysm (AAA). The aneurysm was excluded 2 weeks later from antegrade perfusion by a stent graft. The wireless pressure sensor was positioned in the AAA external to the stent graft. A Konigsberg intraluminal solid-state strain-gauge pressure transducer (Konigsberg Instruments, Pasadena, Calif) that is accurate in the presence of thrombus served as the control to determine AAA pressure. Both of the transducers were implanted on the luminal surface of the aneurysm, 180 degrees opposite from the Carrel patch and endoleak channel. Intra-aneurysmal pressure resulting from the type II endoleak was measured twice daily for 4 weeks using both transducers. A total of 56 pre-exclusion and 224 post-exclusion distinct pressure determinations were made. Intra-aneurysmal pressure was indexed to the systemic pressure that was simultaneously measured by a strain-gauge pressure transducer implanted in the native aorta. Histologic analysis of the aneurysm contents was performed with hematoxylin and eosin. RESULTS: The intra-aneurysmal systolic, mean, and pulse pressures produced by the type II endoleak were significantly lower than systemic pressure in all animals and were < 60% of systemic pressure (P < .001). Close correlation between the wireless transducer and the control strain-gauge transducer was observed (R = 0.83, P < .001). Arteriography and Doppler ultrasound documented retrograde flow through the aneurysm side branches and persistent endoleak patency up to the time of euthanasia. Pathologic analysis demonstrated the endoleak channel to be patent and separated from the transducers by thrombus, which surrounded both transducers. CONCLUSIONS: Intra-aneurysmal pressure generated by type II endoleaks may be accurately measured through thrombus using a wireless pressure sensor in the canine model. The wireless sensor has the potential for clinical applicability in diagnosing and characterizing type II endoleaks.

Analysis of parameters associated with hypotension requiring vasopressor support after carotid angioplasty and stenting.

INTRODUCTION: Systemic hypotension has been observed for up to 36 hours in response to stimulation of the carotid baroreceptor by carotid angioplasty and stenting (CAS). The aim of this study was to identify risk factors and cardiac outcomes for postprocedural hypotension requiring vasopressor support after CAS. METHODS: Between 2003 and 2005, 143 patients (87 men; mean age, 75 years) with high-grade carotid artery stenosis (mean, 87.3%) were treated with CAS and prospectively entered into a vascular registry. Data were retrospectively analyzed to determine factors predictive of hypotension requiring vasopressor support after CAS. Atropine and appropriate intravenous crystalloid solution were administered during CAS. For the first 30 patients, atropine was only used for symptomatic patients but then became routine and was used for all patients with primary carotid stenosis. Hypotension (systolic blood pressure <90 mm Hg or a mean arterial blood pressure <50 mm Hg) unresponsive to conservative measures was treated with vasopressors (phenylephrine or norepinephrine). Patients were stratified into three groups based on hypotension requiring vasopressors: (1) no vasopressors, (2) vasopressors for < or = 24 hours (short duration), and (3) vasopressors for >24 hours (prolonged duration). Risk factors for hypotension requiring vasopressors were analyzed by univariate and multivariate logistic regression analysis. RESULTS: Postprocedural hypotension requiring vasopressor treatment was seen in 16 (11%) of 143 of patients, with 6 (4%) requiring vasopressor support for >24 hours. Mean duration of vasopressor administration for all patients was 17 +/- 10 hours (range, 6 to 36 hours). By univariate analysis, a history of a previous myocardial infarction (P = .02) or use of the PercuSurge occlusion balloon (P = .05) were both associated with increased incidence of short duration (80 years old (P = .02) were associated with prolonged (>24 hours) vasopressor requirement. On multivariate analysis adjusted for age and sex, a history of myocardial infarction (odds ratio [OR], 4.1; 95% confidence interval [CI], 1.0 to 16.4; P = .05) remained an independent predictor of short-duration vasopressors. On multivariate analysis, female sex (OR, 10.9; 95% CI, 1.2 to 100.4; P = .04) and age >80 years old (OR, 13.8, 95% CI, 1.5 to 127.2; P = .02) remained independent predictors of prolonged vasopressor use. The incidence of periprocedural myocardial infarctions, arrhythmias, or congestive heart failure did not differ between those patients who did not receive vasopressors (5/127) and those who received vasopressors for a short (< or = 24 hours) duration (1/10, P = NS) or prolonged (>24 hours) duration (0/6, P = NS). CONCLUSION: Prolonged hypotension requiring vasopressor support occurs in a minority of patients after CAS, with higher incidences in older women. In contrast, hypotension requiring a more limited duration of vasopressor use occurs more commonly in patients who had a prior myocardial infarction, independent of age or sex. In this cohort of patients, vasopressors required for hypotension were not associated with an increased incidence of periprocedural cardiac complications. Despite the increased incidence of prolonged hypotension in older women, this study demonstrates that CAS can be performed without an increase in cardiac morbidity in older women.

The development of endotension is associated with increased transmission of pressure and serous components in porous expanded polytetrafluoroethylene stent-grafts: characterization using a canine model.

OBJECTIVE: This study used a canine model of abdominal aortic aneurysms (AAAs) to compare intra-aneurysmal pressure and thrombus formation after exclusion with Dacron and expanded polytetrafluoroethylene (ePTFE) stent-grafts. METHODS: Prosthetic AAAs with implanted strain-gauge pressure transducers were treated by stent-graft exclusion using Food and Drug Administration-approved devices in 10 mongrel dogs: five Dacron (AneuRx) and five ePTFE (original Excluder). Intra-aneurysmal pressure was measured over 4 weeks after AAA exclusion and indexed to the systemic pressure, represented as a percentage of a simultaneously obtained systemic pressure (value = 1.0). Magnetic resonance imaging (MRI) of the intra-aneurysmal thrombus was performed at 1, 2, and 4 weeks after exclusion and expressed as a signal-to-noise ratio (S:N) to control for background signal intensity. Comparisons of pressures and S:N between the two stent-grafts was analyzed with the Student's t test. Intra-aneurysmal thrombus was characterized histologically. RESULTS: In animals excluded with both Dacron and ePTFE stent-grafts, the intra-aneurysmal pressure was nonpulsatile and reduced to <30% of systemic pressure. Significantly greater pressure transmission was observed after AAA exclusion using ePTFE compared with Dacron stent grafts (systolic pressure: ePTFE, 0.28 +/- 0.12 vs Dacron, 0.11 +/- 0.02, P < .001; mean pressure: ePTFE, 0.16 +/- 0.08 vs Dacron, 0.06 +/- 0.02, P < .001). MRI confirmed the absence of perfusion in all aneurysms. The T1-weighted signal intensity remained persistently elevated (S:N at 1 week, 2.7 +/- 0.4 vs 2 weeks, 4.0 +/- 0.2 vs 4 weeks, 5.4 +/- 1.3) in ePTFE-treated intra-aneurysmal thrombus, suggesting an absence of thrombus organization. In contrast, progressive evolution of T1 signal intensity in aneurysms excluded by Dacron stent-grafts was consistent with maturation from intact red blood cells (S:N at 1 week, 3.3 +/- 0.4) to methemoglobin (S:N at 2 weeks, 6.1 +/- 0.8), and then hemosiderin and ferritin (S:N at 4 weeks, 2.4 +/- 0.5). Histologically, ePTFE-excluded aneurysms contained poorly organized thrombus with red blood cell fragments and haphazardly arranged fibrin deposition indicative of active remodeling and continued influx of transudated serum. In aneurysms excluded by Dacron stent-grafts, dense, mature collagenous connective tissue and organized fibrin were present, indicative of greater thrombus organization. CONCLUSIONS: Stent-graft treatment reduces intra-aneurysmal pressure to <30% of systemic pressure when no endoleak is present; however, significantly greater pressure is present in aneurysms treated with porous ePTFE stent-grafts than Dacron grafts. Histologic and MRI imaging analysis suggest that active transudation of serous blood components may be contributing to this increased intra-aneurysmal pressure.

Analysis of outcomes following failed endovascular treatment of chronic limb ischemia.

Despite recent studies highlighting the advantages of endoluminal intervention in the management of chronic limb ischemia (CLI), outcomes following failed peripheral angioplasty remain less well described. We present a retrospective analysis of failed transluminal infrainguinal percutaneous arterial angioplasty with or without stenting (PTA/S) in patients with CLI. A database of patients undergoing infrainguinal PTA/S between 2002 and 2005 was maintained. Patients underwent duplex scanning follow-up at 2 weeks, 3 months, and every 6 months after the intervention. Angiograms were reviewed in all cases to assess lesion characteristics. Results were standardized to current Transatlantic Inter-Society Consensus (TASC) criteria. Kaplan-Meier survival analyses were performed to assess time-dependent outcomes. In total, our analysis involved 246 patients who underwent treatment for CLI using PTA/S. Eighteen percent of procedures (n = 46) were considered an intervention failure secondary to restenosis by duplex ultrasound, returning clinical symptoms, a nonhealing foot lesion, or the absence of a prior palpable pulse. Indications for the original procedure in patients whose PTA/S failed were tissue loss in 44%, claudication in 44%, and rest pain in 12%, while TASC lesion grades were A (0%), B (18%), C (18%), and D (64%). Of patients failing PTA/S, 4% failed in the first 30 days, 78% failed between 1 and 18 months, while 18% failed following 18 months, with a mean time to failure of 8.7 months. Also, 82% of PTA/S failures were candidates for a second endovascular procedure, 11% were suitable for only traditional open bypass, and 4% demonstrated progression of disease necessitating amputation. Of patients undergoing a second endovascular procedure, limb salvage rates were 86% at 12-month follow-up and there was a single periprocedural mortality and complication rate of 6.6%. Of patients requiring open surgical bypass after failed PTA/S, 20% (n = 1) required a major amputation and there were no mortalities. Failure of endoluminal therapy for treatment of lower extremity arterial occlusive disease is amenable to subsequent endovascular intervention for limb salvage with limited morbidity and mortality.

Analysis of anatomic factors and age in patients undergoing carotid angioplasty and stenting.

Recent data suggest that patient age >80 years may be associated with increased risk of periprocedural complications from carotid angioplasty and stenting (CAS). In this study, we analyzed anatomic risk factors in patients undergoing CAS based on age >80 or <80 years. Our hypothesis was that patients >80 would have more challenging anatomy. Between February 2003 and August 2004, 82 patients underwent CAS. Images for 57 lesions were available for review. Eighteen patients were > or =80 years old and 39 were <80. Cerebral protection devices, including EPI Filterwire, Percusurge, Accunet, and Angioguard, were used in all but two cases; and self-expanding stents (Wallstent, NexStent, Acculink, Precise) were placed in all. Arterial anatomic characteristics were assigned a score based on complexity and associated procedural risk. Characteristics evaluated using angiographic images were aortic arch elongation classification, arch calcification, common carotid/innominate stenosis, common carotid tortuosity, internal carotid tortuosity, index lesion length, index lesion calcification, and index lesion stenosis. Statistical analysis was performed using Fisher's exact test. CAS was successfully completed in 98% of cases. The two patients in whom we could not perform CAS were 79 and 83 years old. The anatomic characteristics that were statistically significantly more complex/severe in patients > or =80 were arch calcification (p = 0.045), common carotid/innominate stenosis (p = 0.023), common carotid tortuosity (p = 0.049), and internal carotid tortuosity (p = 0.032). There was no statistically significant difference in arch elongation classification, lesion length, lesion calcification, or stenosis severity (p = nonsignificant). Overall, patients > or =80 years had an increased incidence of complex anatomic risk factors compared to younger patients (p < 0.001). Cerebrovascular accident without residual deficits occurred in two patients; both were >80 years old. Complex arterial anatomy is more often present in patients >80 years and may explain the increased complication rates associated with CAS. Pre- or intraoperative consideration of these characteristics may help provide better risk assessment in candidates for CAS.