Mark Langsfeld

Technique and results of transfemoral superselective coil embolization of type II lumbar endoleak

OBJECTIVE This study was undertaken to describe the technique of transfemoral superselective coil embolization of type II endoleak and its influence on abdominal aortic aneurysm diameter. METHODS Over 23 months, 104 aortic stent grafts were deployed to exclude abdominal aortic aneurysms, at an academic medical center. Increase in aneurysm diameter and perigraft findings on contrast material-enhanced computed tomography scans prompted arteriography. Procedures were performed solely by vascular surgeons in a surgical angiography suite. In 7 patients aneurysm access was via the iliolumbar branches of the internal iliac artery, and in 1 patient aneurysm access was via the inferior mesenteric artery through the arc of Riolan from the superior mesenteric artery. Coaxial catheters were placed to gain access to the aneurysm (8F to 5F to 3F, or 5F to 3F). A 3F Tracker18 was the most distal catheter through which an assortment of 0.018 microcoils were deployed within the aneurysm, and the origin of the feeding vessels when possible. RESULTS Aneurysm diameter increased 0.48 +/- 0.2 cm over 10.8 +/- 5 months before superselective coil embolization. In 6 of 8 patients superselective coil embolization embolization resulted in a mean decrease in aneurysm diameter of 1.3 +/- 1.2 cm over 9 +/- 3.2 months. Failure was presumed due to inability to reach the aneurysm sac in 1 patient and was associated with oral anticoagulation in 1 other patient. CONCLUSION Proper identification of the source of type II endoleak and its complete occlusion, combined with aneurysm sac coiling, may result in prompt decrease in aneurysm size.

Baker's cysts mimicking the symptoms of deep vein thrombosis: Diagnosis with venous duplex scanning

PURPOSE The purpose of this study was to determine the incidence and characteristics of Bakers cysts discovered during venous duplex examinations to rule out deep vein thrombosis (DVT). METHODS We reviewed the vascular laboratory charts of patients found to have Bakers cysts during venous duplex studies to rule out DVT from October 1988 through December 1995. RESULTS Ninety-five (3.1%) of 3072 patients who underwent venous duplex studies were found to have 111 Bakers cysts. Seven of the 95 had coexistent DVT. Ten patients had ruptured cysts, whereas six patients had cysts that compressed the popliteal vein. CONCLUSION The presentation of DVT and that of a Bakers cyst are similar enough to be difficult to distinguish by clinical examination. Careful examination of the popliteal fossa should be performed during venous duplex examinations regardless of the indication for the study.

Covered Stents for True Subclavian Aneurysms in Patients with Degenerative Connective Tissue Disorders

Purpose: To report the endovascular repair of rare true aneurysms of the subclavian artery in patients with degenerative connective tissue disorders. Case Reports: Two patients, one with Marfan syndrome and the other with idiopathic cystic medial necrosis, presented with 3 subclavian artery aneurysms. A Wallgraft and 2 Viabahn covered stents were used to successfully exclude these aneurysms. After 3 months, the Wallgraft thrombosed, but the contralateral Viabahn remained patent at the most recent examination 13 months after treatment. The other patient with the unilateral aneurysm had a patent Viabahn stent-graft at 10 months. Conclusions: Patients with degenerative connective tissue disorders may benefit from less invasive treatment with stent-grafts. The more flexible Viabahn stent-graft may be better able to adapt to arterial tortuosity. However, the long-term results of this new technique have not yet been established.

Complication Rates of Diagnostic Angiography Performed by Vascular Surgeons

The objective of this study was to compare the complication rates of diagnostic angiography performed by vascular surgeons to those previously published by interventional radiologists. From May 1999 through August 2000, 3 board-certified vascular surgeons performed 224 endovascular procedures in a modern endovascular suite. Of these 224 procedures, 144 were diagnostic angiographies. A retrospective chart review was conducted to identify periprocedural complications of these angiographies. The patients were classified into 3 groups according to the indication for angiography, and the major and overall complication rates were tabulated. The complication rates for the initial 25 and subsequent 119 arteriographies were compared to evaluate the presence of a learning curve. Thirty-eight percent of angiographies were performed to define aneurysmal anatomy (type I), 51% to define peripheral arterial stenosis or occlusion (type II), and 12% to assess symptomatic carotid artery disease or mesenteric ischemia (type III). The major complication rates for these 3 types were 0%, 2.7%, and 5.9%, respectively, and showed no statistical difference (Fischers exact test) compared to published rates of 0.7%, 2.9%, and 9.1%. Major complications included an external iliac artery dissection, a cerebral air embolus, and a deep venous thrombosis. The overall major complication rate was 2.1%, which compares to published rates of 1.9-2.9%. The major complication rates for the initial 25 and final 119 were 8% and 0.8%, respectively. Vascular surgeons can perform diagnostic angiography with acceptable complication rates. The complication rate is reduced with angiographic experience.

Evaluating institutional variability of duplex scanning in the detection of carotid artery stenosis

PURPOSE Duplex scanning is widely used to measure carotid artery stenosis, but the issue of variability between institutions must be raised. To examine for this potential variability, we evaluated two ATL Ultramark 9 duplex machines at two hospitals within our institution. METHODS Stenosis was calculated angiographically as in the North American Symptomatic Carotid Endarterectomy Trial (NASCET). Internal carotid artery (ICA) to common carotid artery (CCA) peak systolic velocity (PSV) ratios were determined using the two ATL machines. Receiver operating characteristic (ROC) curves were generated for each hospital. RESULTS ROC curves varied significantly. The area under the curve from hospital 1 was 0.95 (SE = 0.021); the area under the curve from hospital 2 was 0.87 (SE = 0.034). The curves were essentially statistically different (P = 0.0516). COMMENTS We showed a difference in predicting diameter stenosis utilizing ICA PSV/CCA PSV ratios at two hospitals within our institution. Variability is likely due to technologists, since equipment and physician interpreters were the same. Criteria must be developed for each different machine in each laboratory. Quality assurance is critical to minimize variability.

INFECTION IN THE ISCHEMIC LOWER EXTREMITY

Infections in the lower extremity of the patient with ischemia can cover a broad spectrum of different diseases. An understanding of the particular pathophysiologic circumstances in the ischemic extremity can be of great value in understanding the natural history of the disease and the potential complications that may occur. Optimizing blood flow to the extremity by using revascularization techniques is important for any patient with an ischemic lower extremity complicated by infection or ulceration. Infections in the ischemic lower extremity require local débridement and systemic antibiotics. For severe infections, such as necrotizing fasciitis or the fetid foot, more extensive local débridement and even amputation may be required. Fundamentals of managing prosthetic graft infection require removing the infected prosthesis, local wound débridement, and systemic antibiotics while attempting to preserve viability of the lower extremity using autogenous graft reconstruction.

Post-Endovascular Aneurysm Repair Patient Outcomes and Follow-up Are Not Adversely Impacted By Long Travel Distance to Tertiary Vascular Surgery Centers

BACKGROUND To determine whether patient adherence to follow-up and patient outcomes after endovascular aneurysm repair (EVAR) are affected by the distance between a patients residence and a tertiary care treatment center. METHODS A retrospective review of 136 consecutive patients undergoing EVAR at the New Mexico Veterans Affairs Medical Center over a 7-year period was conducted. Patients were stratified as living within a 100-mi radius of the treatment center (group 1) and those living outside this radius (group 2). Follow-up included clinic visits and computed tomography scans at 1 month after discharge, every 6 months for 2 years, and then yearly. Incomplete follow-up was defined if two or more consecutive appointments were missed. Survival and graft-related complication rates were analyzed for both the patient groups. RESULTS Of the 136 patients, 10 patients died from nonaneurysm-related causes less than 1 year after their EVAR procedures, and hence were not a part of the study. Of the surviving patients, 44% lived within a 100-mi radius of the treatment center (group 1), and 56% outside this 100-mi radius (group 2). The mean patient follow-up time was 52.1 ± 25.9 months. Of the surviving patients, 15% had inadequate follow-up, yet there was no significant difference in the adequacy of follow-up for patients in group 1 compared with group 2. The incidence of major complications, defined as aneurysm rupture, conversion to open repair, myocardial infarction, and stroke, was not statistically different in group 1 versus group 2 (5.0% vs. 11.8%, p = 0.23). Of the five patients (3.7%) who died as a result of abdominal aortic aneurysms related causes, three were in group 1 and two in group 2. CONCLUSIONS Distance from a tertiary care center is not a limiting factor in patient adherence to follow-up, patient graft-related morbidity, or patient survival, likely because of the Albuquerque VA Medical Centers electronic tracking of patients and provision of travel vouchers.

Screening algorithm for aortoiliac occlusive disease using duplex ultrasonography-acquired velocity spectra from the distal external iliac artery

Aortoiliac duplex scanning can be difficult to perform owing to the deep location of these vessels. We propose a new method to indirectly screen for aortoiliac disease by performing duplex examination of the distal external iliac artery (DEIA). After performing a preliminary study on 21 patients, the parameters of the Doppler waveform that best distinguish normal from diseased arteries were the presence or absence of reverse flow, peak systolic velocity, and resistance index. These values were used in a derived equation, with the value Y ≥ 0.78 predicting normal proximal inflow. We then studied 118 aortoiliac segments in 81 consecutive patients with arteriography and DEIA duplex ultrasonography. To predict moderate to severe stenosis, duplex ultrasonography had a sensitivity of 95.7%, a specificity of 84.1%, a positive predictive value of 80%, and a negative predictive value of 96.8%. Our formula thus predicted significant disease in 55 of the 118 aortoiliac segments (47%), with these segments needing further arteriographic evaluation. The other 63 limbs can be safely considered as having normal aortoiliac inflow. Our method accurately screens for aortoiliac disease and is excellent for predicting normal inflow. This information can be used to better plan the intraoperative diagnostic study and intervention.

Comparison of nonneurological events in high-risk patients treated by carotid angioplasty versus endarterectomy

OBJECTIVE To compare results of carotid angioplasty and stenting (CAS) with carotid endarterectomy (CEA) in high cardiac risk patients. METHODS Patients ineligible for carotid revascularization by North American Symptomatic Carotid Endarterectomy Trial/Asymptomatic Carotid Atherosclerosis Study criteria were treated with CAS (n = 11) or CEA (n = 10). RESULTS Significant numbers had cardiac (CAS 72%, CEA 60%; P = 0.66) and hypertensive (CAS 82%, CEA 80%; P = 0.64) risk factors. Adverse hemodynamic events were more frequent in the CAS group (CAS 73%, CEA 20%; P = 0.03). Major complications were noted in 1 patient in each group (CAS, myocardial infarction; CEA, death). Postoperative stay was similar (CAS 2.1 +/- 1.4, CEA 1.8 +/- 1.1 days; P = 0.60). However, 4 in the CAS group were readmitted within 1 month (congestive heart failure 2, myocardial infarction 1, rest pain 1), compared with no new events in the CEA group (P = 0.09). CONCLUSIONS Currently, the use of CAS in patients with cardiac risk factors may not be justifiable.

Association of serum aryl hydrocarbon receptor activity and RBC omega-3 polyunsaturated fatty acids with flow-mediated dilation in healthy, young Hispanic cigarette smokers.

Impaired flow-mediated dilation (FMD) occurs prior to clinical disease in young cigarette smokers. We investigated two potential biomarkers of FMD: serum aryl hydrocarbon receptor (AHR) activity and RBC omega-3 polyunsaturated fatty acids in healthy young Hispanic cigarette smokers. We recruited never (n=16) and current (n=16) Hispanic smokers (32 ± 7 years old), excluding individuals with clinical cardiovascular disease. We measured FMD with duplex ultrasound, RBC fatty acids and serum AHR activity using a luciferase reporter assay. FMD was significantly impaired in smokers (5.8 ± 4%) versus never smokers (12.3 ± 7.4%, p=0.001). Serum AHR activity was significantly increased in smokers (1467 ± 358 relative light units (RLU)) versus never smokers (689 ± 251 RLU, p<0.001), and correlated positively with FMD only in smokers (r=0.691, p<0.004). RBC percentage of α-linolenic acid (ALA%) was significantly increased in smokers (0.14 ± 0.03%) versus never smokers (0.11 ± 0.03%, p=0.018), and correlated inversely with FMD only in smokers (r=-0.538, p=0.03). The combination of serum AHR activity, ALA%, and systolic blood pressure significantly correlated with FMD in a multivariable regression model (r=0.802, p<0.008). These results suggest that serum AHR activity and RBC ALA% could serve as biomarkers of FMD in healthy, young Hispanic cigarette smokers.