Biomedical subjects

Luis R Leon

Publications and source records attributed to Luis R Leon.

9 recordsLinked to original sources

PubMed2007

Free-floating thrombus of the carotid artery: literature review and case reports.

BACKGROUND: Free-floating thrombus (FFT) of the carotid artery is an uncommon entity that usually presents as an acute emergency. Management is based on case reports and series because the natural history and optimal treatment are unknown. This study was conducted to systematically review the world literature in an attempt to better understand FFT, its presentation, distribution, management, and outcome. METHOD: A literature search in all languages was performed of the PubMed database (> or =1950s) and Medline database (1966-November 2004). All relevant articles were reviewed and their references analyzed in a similar manner for further literature. Cases from the authors' institutions were reviewed as well. All cases within the reports were individually assessed for inclusion or exclusion. Inclusion required that the FFT originate or anchor within the carotid artery (ie, excluding emboli, arch thrombi with extensions into the carotid artery), be partially occluding (ie, excluding occlusions, "string-sign," microscopic thrombus), and ideally have an elongated or protrusive morphology, circumferential flow around the distal portion, and cyclical motion with the cardiac cycles. RESULTS: There were 61 reports reviewed, of which 43 contained FFT cases. These reports had 342 cases (including the current series) that were reviewed, of which 145 met our inclusion criteria. A database was created for qualitative and quantitative assessment of all cases. When data were pooled, appropriate statistical analysis was performed. A limitation of the study is that FFT is under-reported and ill defined, which limited the analysis in quantity and quality. In addition, reporting is not uniform, and therefore, significant data were not always present. In attempting to define FFT and include or exclude cases, subjectivity is inherent. CONCLUSIONS: FFT is more frequently reported in men than women, with a ratio of nearly 2:1 (P < .0001), and at a younger age than in most patients with carotid disease (P < .0001 when compared with North American Symptomatic Carotid Endarterectomy Trial, European Carotid Surgery Trial, and Asymptomatic Carotid Surgery Trial). Symptoms are present in 92% of patients. There was a trend for patients with FFT to be hypercoagulable (47% of those serologically tested). The internal carotid artery was the most commonly affected (75%), with atherosclerosis being the most common associated pathology. Medical and surgical management have both been used, with neither clearly superior to the other. Medical management for stabilizing neurologic deficits has less risk and less benefit than surgical intervention.

Angiography↗

PubMed2006

Excision of internal jugular vein for catheter-related thrombophlebitis.

This report describes a case of internal jugular vein (IJV) thrombophlebitis refractory to intravenous (IV) antibiotics and anticoagulation managed with ligation and excision of the vein. Our patient was immunosuppressed for a transplanted organ and developed a catheter-related infection following major pelvic surgery. His symptoms worsened, and failure of medical management prompted operative intervention. Excision of the inflamed, thrombosed vein led to complete resolution of his symptoms.

Catheterization, Central Venous↗

PubMed2006

Presentation of the patient with recurrent varices after surgery (REVAS).

AIM: To identify in patients with recurrent varices after surgery (REVAS) the clinical, etiologic, anatomic, and pathophysiologic patterns according to the CEAP classification, as well as the site, source, causes of recurrence, and contributory factors by using the REVAS classification. METHODS: Centers from eight countries enrolled patients with superficial vein reflux that had had a previous operation. A physical examination and a duplex ultrasound scan were performed at the first visit. This was repeated between 2 to 8 weeks after by the same physician and by another physician within the same time frame. The perforator, deep, and superficial veins systems as well as their accessories and tributaries were examined. A form based on the CEAP and the REVAS classification was used and the data were entered in a customized database. RESULTS: Fourteen institutions enrolled 170 patients (199 lower limbs) in 1 year. Their mean age was 56 years, and 69% were women. Most of them had undergone one surgical procedure before enrollment (76.6%). Most had varicose veins and swelling (70.9%), and the rest had skin damage (29.1%). More than 90% had primary etiology. The saphenofemoral junction (47.2%) and leg perforators (54.7%) were the areas most often involved by recurrent reflux. Reflux in deep veins was detected in 27.4%. Class 2 (varicose veins) alone was present in 24.6% of limbs, two classes were present in 43%, and three in 24%. Neovascularization was as frequent as technical failure (20% vs 19%); both were seen in 17%. In 35%, the cause was uncertain or unknown. When recurrence occurred at a different site, development of reflux in new sites was found in 32% of limbs. Of the contributing factors, family history and lifestyle had the highest prevalence. Women had significantly more procedures than men, despite a clear trend toward more severe disease in the latter. CONCLUSIONS: Most patients were symptomatic with several clinical forms of presentation. The REVAS classification, together with CEAP, gives significant and more appropriate information for evaluating and following-up patients with chronic venous disease who have had an intervention.

Adult↗

PubMed2005

To what extent has endovascular aneurysm repair influenced abdominal aortic aneurysm management in the state of Illinois?

PURPOSE: This study was performed using population-based data to determine the changing trends in the techniques for abdominal aortic aneurysm (AAA) repair in the state of Illinois during the past 9 years and to examine the extent to which endovascular aneurysm repair (EVAR) has influenced overall AAA management. METHODS: All records of patients who underwent AAA repair (1995 to 2003 inclusive) were retrieved from the Illinois Hospital Association COMPdata database. The outcome as determined by in-hospital mortality was analyzed according to intervention type (open vs EVAR) and indication (elective repair vs ruptured AAA). Data were stratified by age, gender, and hospital type (university vs community setting) and then analyzed using both univariate (chi 2 , t tests) and multivariate (stepwise logistic regression) techniques. RESULTS: Between 1995 and 2003, 14,517 patients underwent AAA repair (85% for elective and 15% for ruptured AAA). The average age was 71.4 +/- 7.9 years, and 76% were men. For elective cases, open repair was performed in 86% and EVAR in 14%; and for ruptured cases, open repair in 97% and EVAR in 3%. Elective EVAR was associated with lower in-hospital mortality compared with open repair regardless of age. No differences were observed with age after either type of repair for a ruptured aneurysm. Men had a lower in-hospital mortality compared with women for open repair of both elective and ruptured aneurysms. For EVAR, the mortality of an elective repair was lower in men, but there was no difference after a ruptured AAA. In men, the difference in mortality between elective open repair and EVAR was significant; the type of institution did not influence outcome. Patients >80 years of age had a higher mortality after open repair for both elective and ruptured AAA and after EVAR of a ruptured AAA. The average length of stay was 9.9 days for open elective repair, 13.1 days after open repair of a ruptured AAA, and 3.6 days for EVAR. The independent predictors of higher in-hospital mortality were female gender, age >80 years, diagnosis (ruptured vs open), and procedure (open vs EVAR). The year of the procedure and type of hospital (university vs community) were not predictive of outcome. CONCLUSIONS: EVAR has had a significant impact on AAA management in Illinois over a relatively short time period. In this population-based review, EVAR was associated with a significantly decreased in-hospital mortality and length of stay. Octogenarians had higher mortality after both types of repair, with the exception of elective EVAR.

Age Factors↗

PubMed2005

Hemodynamic effects of intermittent pneumatic compression in patients with critical limb ischemia.

BACKGROUND: Traditional teaching assumes that the distal arterial tree is maximally dilated in patients with critical limb ischemia (CLI). Endovascular or arterial bypass procedures are the commonly used interventions to increase distal perfusion. However, other forms of treatment such as spinal cord stimulation or intermittent pneumatic compression (IPC) have been shown to improve limb salvage rates. This prospective study was designed to determine if the use of IPC increases popliteal, gastrocnemial, collateral arterial, and skin blood flow in patients with CLI. METHODS: Twenty limbs with CLI in 20 patients (mean age, 74 years) were evaluated with duplex ultrasound scans and laser Doppler fluxmetry in the semi-erect position before, during, and after IPC. One pneumatic cuff was applied on the foot and the other on the calf. The maximum inflation pressure was 120 mm Hg and was applied for 3 seconds at three cycles per minute. All patients had at least two-level disease by arteriography. Fourteen limbs were characterized as inoperable, and six were considered marginal for reconstruction. Flow volumes were measured in the popliteal, medial gastrocnemial, and a genicular collateral artery. Skin blood flux was measured on the dorsum of the foot at the same time. RESULTS: Significant flow increase during the application of IPC was found in all three arteries (18/20 limbs) compared with baseline values (P < .02). The highest change was seen in the popliteal, followed by the gastrocnemial and the collateral artery. After the cessation of IPC, the flow returned to baseline. This was attributed to the elevation of time average velocity, as the diameter of the arteries remained unchanged. The skin blood flux increased significantly as well (P < .03). In the two limbs without an increase in the arterial or skin blood flow, significant popliteal vein reflux was found. Both limbs were amputated shortly after. CONCLUSIONS: IPC increases axial, muscular, collateral, and skin blood flow in patients with CLI and may be beneficial to those who are not candidates for revascularization. Patients with significant venous reflux may not benefit from IPC. This supports the theory that one of the mechanisms by which IPC enhances flow is by increasing the arteriovenous pressure gradient.

Aged↗

PubMed2005

Duplex evaluation of venous insufficiency.

Duplex ultrasound is the most useful examination for the evaluation of venous valvular incompetence. Multi-frequency 4 to 7-MHz linear array transducers are typically used for this assessment of superficial and deep reflux. The examination is done with the patient standing and manual compression maneuvers are used to initiate reflux. Automatic rapid inflation and deflation cuffs may be used when a standard stimulus is needed. Cutoff values for reflux have been defined. Perforating veins must be identified and flow direction during compression recorded. When ulcers are present, duplex ultrasound is used to investigate veins of the ulcerated legs. Venous outflow obstruction is also studied by duplex ultrasound and chronic changes in deep and superficial veins following deep venous thrombosis noted. The main drawback in evaluation of chronic obstruction is inability to quantify hemodynamic significance. Anatomic variations in superficial and deep veins are common and their identification is necessary. Reporting results of duplex ultrasound studies must take into consideration the proper classification of venous disease as well as the new anatomic terms that have been accepted.

Humans↗

PubMed2005

Superficial vein thrombosis and hypercoagulable states: the evidence.

AIM: To assess the demographic features of superficial vein thrombosis and its relation with the occurrence of hypercoagulable states. METHODS: Data were gathered from pertinent papers using a MEDLINE search and an exhaustive bibliography review. Studies were considered only when they contained material to superficial vein thrombosis and hypercoagulable states. RESULTS: The difference among the patients and the methods used made the comparison difficult and did not allow a pool analysis of the data. Superficial vein thrombosis is a common condition, and its prevalence is underestimated. Several risk factors are associated with superficial vein thrombosis, and a strong relation was seen with certain thrombophilias. CONCLUSIONS: Although superficial vein thrombosis most often is perceived as benign, it can coexist with hypercoagulable states. In patients with spontaneous onset of superficial vein thrombosis, there should be a lower threshold in testing for hypercoagulable states.

Comorbidity↗

PubMed2005

The vascular surgeon's role in risk factor modification: results of a survey.

PURPOSE: Comprehensive care of vascular patients includes attention to atherosclerotic risk factor management. We surveyed members of the Midwestern Vascular Surgical Society (MVSS) with the following objectives: (1) to determine the usual practice pattern with respect to risk factor inquiry, screening, and intervention, (2) to determine which risk factors vascular surgeons believe are important for patients with peripheral arterial disease, and (3) to determine the vascular surgeon's confidence for management of each risk factor. METHODS: A survey was mailed to all MVSS members and two additional notifications were sent for initial nonresponders. Data regarding practice environment and local resources available to each surgeon were recorded. Questions were designed to determine the prevalence of risk factor inquiry and screening, grading of the importance of each risk factor, and the vascular surgeon's confidence in the management of each risk factor. RESULTS: The survey was completed by 219 (56%) of 391 of MVSS members. The average age of the responders was 53.1 +/- 9.3 years, and 94.1% were men. Seventy-four percent of the surgeons dedicate 90% to 100% of their time to vascular surgery, and 89% dedicate more than 50%. Seventy-seven percent of responders work in a private institution and 23% in a public hospital. The surgeon's practice had a full- or part-time affiliation with a medical school in 62% and was entirely community-based in 38%. A high proportion of surgeons inquire about each risk factor, but only a minority performs the actual screening of the risk factors, with the exception of hypertension. Diabetes mellitus and smoking were believed to be very important risk factors, hypertension and lipids of moderate importance, and exercise and activity, nutrition, and homocysteine level of low importance. The surgeons' confidence in risk factor management was low to moderate for most risk factors, but high for smoking and exercise. Despite these responses, only 10% of vascular surgeons thought that they should be primarily responsible for risk factor management. CONCLUSIONS: Vascular surgeons must provide a comprehensive approach to risk factor management for their patients. This can be conducted through the establishment of multidisciplinary risk factor programs or by the surgeon in certain cases when outside resources are not available. Risk factor management must be emphasized in vascular continuing medical education programs to enable surgeons to be confident with management.

Arteriosclerosis↗

PubMed2005

Aortic endograft migration.

Despite the popularity of endovascular repair of abdominal aortic aneurysms, important issues regarding its long-term efficacy and durability remain. Many hemodynamic and biomechanical forces interact between the endograft, its attachment systems, and the aortic wall. Migration is the longitudinal movement of all or part of the stent-graft. When the magnitude of this displacement is such that endograft seal is lost, repressurization of the previously excluded aneurysmal sac can result. This can lead to catastrophic consequences. In this article, we review the definition, prevalence, diagnosis, clinical implications, and management of stent-graft migration.

Aortic Aneurysm, Abdominal↗