Marcone Lima Sobreira

Results of Open Pararenal Abdominal Aortic Aneurysm Repair: Tabular Review of the Literature

Open surgical repair of complex abdominal aortic aneurysms requires more extensive dissection and aortic clamping above the renal or mesenteric arteries. Although results of open surgical series have shown variation, morbidity and mortality is higher compared with infrarenal aortic aneurysm repair. Potential complications include renal insufficiency, mesenteric ischemia, multisystem organ failure, and death. Although endovascular treatment with fenestrated and branched endografts might potentially decrease the risk of complications and mortality, its role is not yet defined and the technology is not widely available. Issues related to durability of the procedure and secondary interventions might limit its application to patients with higher risk or those with hostile anatomy. This article summarizes the clinical results of open surgical repair of pararenal abdominal aortic aneurysms to provide a benchmark for comparison with results of endovascular treatment, using fenestrated and branched techniques.

Tromboflebite superficial: epidemiologia, fisiopatologia, diagnóstico e tratamento

Superficial thrombophlebitis of the lower limbs is a commonly occurring disease, and it is associated with various clinical and surgical conditions. Historically considered to be a benign disease due to its superficial location and easy diagnosis, its treatment was, for a long time, conservative in most cases. Nevertheless, recent reports of high frequency and associated thromboembolic complications, which vary from 22 to 37% for deep venous thrombosis and up to 33% for pulmonary embolism, have indicated the need for broader diagnostic and therapeutic approaches in order to diagnose and treat such possible complications. The possibility of coexistence of these and other systemic disorders (collagenosis, neoplasia, thrombophilia) interferes with evaluation and influences therapeutic conduct, which may be clinical, surgical or combined. However, due to a lack of controlled clinical assays as well as to a series of uncertainties regarding its natural history, the diagnosis and treatment of superficial thrombophlebitis remain undefined. A literature review was performed analyzing the epidemiology, physiopathology and current status of the diagnosis and treatment of superficial thrombophlebitis.Superficial thrombophlebitis of the lower limbs is a commonly occurring disease, and it is associated with various clinical and surgical conditions. Historically considered to be a benign disease due to its superficial location and easy diagnosis, its treatment was, for a long time, conservative in most cases. Nevertheless, recent reports of high frequency and associated thromboembolic complications, which vary from 22 to 37% for deep venous thrombosis and up to 33% for pulmonary embolism, have indicated the need for broader diagnostic and therapeutic approaches in order to diagnose and treat such possible complications. The possibility of coexistence of these and other systemic disorders (collagenosis, neoplasia, thrombophilia) interferes with evaluation and influences therapeutic conduct, which may be clinical, surgical or combined. However, due to a lack of controlled clinical assays as well as to a series of uncertainties regarding its natural history, the diagnosis and treatment of superficial thrombophlebitis remain undefined. A literature review was performed analyzing the epidemiology, physiopathology and current status of the diagnosis and treatment of superficial thrombophlebitis.

Tissue-engineered blood vessel substitute by reconstruction of endothelium using mesenchymal stem cells induced by platelet growth factors

BACKGROUND Cardiovascular diseases remain leaders as the major causes of mortality in Western society. Restoration of the circulation through construction of bypass surgical treatment is regarded as the gold standard treatment of peripheral vascular diseases, and grafts are necessary for this purpose. The great saphenous vein is often not available and synthetic grafts have their limitations. Therefore, new techniques to produce alternative grafts have been developed and, in this sense, tissue engineering is a promising alternative to provide biocompatible grafts. This study objective was to reconstruct the endothelium layer of decellularized vein scaffolds, using mesenchymal stem cells (MSCs) and growth factors obtained from platelets. METHODS Fifteen nonpregnant female adult rabbits were used for all experiments. Adipose tissue and vena cava were obtained and subjected to MSCs isolation and tissue decellularization, respectively. MSCs were subjected to differentiation using endothelial inductor growth factor (EIGF) obtained from human platelet lysates. Immunofluorescence, histological and immunohistochemical analyses were employed for the final characterization of the obtained blood vessel substitute. RESULTS The scaffolds were successfully decellularized with sodium dodecyl sulfate. MSCs actively adhered at the scaffolds, and through stimulation with EIGF were differentiated into functional endothelial cells, secreting significantly higher quantities of von Willebrand factor (0.85 μg/mL; P < .05) than cells cultivated under the same conditions, without EIGF (0.085 μg/mL). Cells with evident morphologic characteristics of endothelium were seen at the lumen of the scaffolds. These cells also stained positive for fascin protein, which is highly expressed by differentiated endothelial cells. CONCLUSIONS Taken together, the use of decellularized bioscaffold and subcutaneous MSCs seems to be a potential approach to obtain bioengineered blood vessels, in the presence of EIGF supplementation.

Complicações da terapia anticoagulante com warfarina em pacientes com doença vascular periférica: estudo coorte prospectivo

OBJECTIVE: To prospectively study the frequency of complications in patients treated with warfarin followed at Botucatu Medical School. METHODS: Patients randomly selected among those with appointments scheduled from June 2002 to February 2004. At the first appointment, a protocol was filled with identification and clinical data. At every return or when the patient went to the hospital due to clinical events, another form was filled with the international normalized ratio, existence and type of clinical event and the conditions of use of vitamin K antagonists. RESULTS: A total of 136 patients (61 men and 75 women), were followed; 99 patients with venous thromboembolism and 37 with arterial disease; 59 were from Botucatu and 77 were from other municipalities. Thirty clinical events were registered: nine of them were not related to the use of warfarin and 21 were hemorrhagic complications (38.8 per 100 patients-year). One hematemesis was considered severe (1.9 per 100 patients-year). The others were considered moderate or mild. There were no deaths, intracranial hemorrhage or cutaneous necrosis. The only significant association was frequency of hemorrhage and average international normalized ratio level. CONCLUSION: Our results demonstrate the feasibility of this treatment in vascular patients in our country, even in socially and economically poor populations, when treated in specialized clinics.

Morphofunctional characterization of decellularized vena cava as tissue engineering scaffolds

Clinical experience for peripheral arterial disease treatment shows poor results when synthetic grafts are used to approach infrapopliteal arterial segments. However, tissue engineering may be an option to yield surrogate biocompatible neovessels. Thus, biological decellularized scaffolds could provide natural tissue architecture to use in tissue engineering, when the absence of ideal autologous veins reduces surgical options. The goal of this study was to evaluate different chemical induced decellularization protocols of the inferior vena cava of rabbits. They were decellularized with Triton X100 (TX100), sodium dodecyl sulfate (SDS) or sodium deoxycholate (DS). Afterwards, we assessed the remaining extracellular matrix (ECM) integrity, residual toxicity and the biomechanical resistance of the scaffolds. Our results showed that TX100 was not effective to remove the cells, while protocols using SDS 1% for 2h and DS 2% for 1h, efficiently removed the cells and were better characterized. These scaffolds preserved the original organization of ECM. In addition, the residual toxicity assessment did not reveal statistically significant changes while decellularized scaffolds retained the equivalent biomechanical properties when compared with the control. Our results concluded that protocols using SDS and DS were effective at obtaining decellularized scaffolds, which may be useful for blood vessel tissue engineering.

Estudo comparativo da evolução e sobrevida de pacientes com claudicação intermitente, com ou sem limitação para exercícios, acompanhados em ambulatório específico

BACKGROUND: Risk factors for atherosclerotic disease acting on natural history are well established, as well as the benefits of physical training in the treatment of intermittent claudication (IC). However, current data do not provide enough information about the relationship between clinical limitations and risk factors and the performance of physical training and its implications on the evolution and mortality of these patients. OBJECTIVE: To compare the claudication distance and survival of patients with IC throughout time in a specific outpatient setting, with or without limitation for exercises. METHODS: A retrospective cohort study was performed to review the protocols of 185 patients and 469 returns, from 1999 to 2005, evaluating demographic data, average claudication distance and death. The data were analyzed using the software Epi-Info, version 3.2, and SAS, version 8.2. RESULTS: Mean age was 60.9±11.1 years; 61.1% were males and 38.9% were females; 87% were Caucasians and 13% were non-Caucasians. Associated risk factors were hypertension (69.7%), smoking (44.3%), dyslipidemia (32.4%), and diabetes (28.6%). For the patients with claudicating distance lower than 500 m, mean initial distance was 154.0±107.6 m and final distance was 199.8±120.5 m. About 45% of the patients had some clinical limitation to perform the prescribed exercise program, such as angina (26.0%), stroke (4.3%), osteoarthrosis (3.8%), previous minor or major amputation (2.1%), or chronic obstructive pulmonary disease (1.6%). About 11.4% of the patients had previous myocardial infarction, and 5.4% of them were using cardiotonic drugs. Mean follow-up time was 16.0±14.4 months. Mean claudication distance increased 100% (418.47 to 817.74 m) throughout 2 years in the group without limitation (p < 0.001) and in nonsmokers (p < 0.001). Survival rate of patients with IC was significantly reduced in the group with limitation for exercises. Logistic regression analysis showed that limitation to exercises was the single factor significantly influencing mortality (p < 0.001). CONCLUSION: Proper and regular exercises and quitting smoking improve claudication distance and reduce mortality rates of these patients, whether by the positive effects of exercises or by controlling risk factors and their adverse effects.

Implante de filtro em veia cava inferior dupla: relato de caso e revisão da literatura

Double inferior vena cava is a rare anatomic variation with prevalence ranging between 0.2-3.0%. In cases of duplication, inferior vena cava filter placement options include placing it in both vena cava, coil-embolization of the intervenous segment plus placing a filter in the right inferior vena cava, or suprarenal filter placement. We report a case of deep venous thrombosis after unilateral primary total hip replacement, presenting with contraindications for anticoagulant therapy, in which cavography showed inferior vena cava duplication. Inferior vena cava filter placement was performed in the supra-renal portion and was proved to be an adequate and safe procedure.

Tratamento da síndrome do roubo devido a fístula arteriovenosa para hemodiálise em membro inferior por meio da técnica de ligadura arterial e revascularização distal (técnica de DRIL)

Universidade Estadual Paulista Faculdade de Medicina de Botucatu Servico de Cirurgia Vascular

Trombose venosa profunda de membros superiores: estudo coorte retrospectivo de 52 casos

Objective: To review the predisposing factors and the evolution of upper-extremity deep vein thrombosis in a series of cases. Methods: Fifty-two consecutive patients (29 men and 23 women, mean age of 52.3 years) with upper-extremity deep vein thrombosis documented by duplex scan (71.1%), phlebography (11.1%) or clinically (15.6%) were included in the study. Results: Clinical manifestations were: forearm pain (24 cases ‐ 46.1%), arm pain (27 cases ‐ 51.9%), upper limb edema (45 cases ‐ 86.5%), pain to arm compression (36 cases ‐ 70.2%) and to arm movement (32 cases ‐ 61.7%). Main risk factors were: vein puncture (20 cases ‐ 39.1%), and cancer (16 cases ‐ 32.6%). Deep vein thrombosis involved humeral (n = 18), axillary (n = 27), subclavian (n = 15) and jugular (n = 11) veins. Pulmonary embolism was initially present in four cases (7.6%). Initial therapy included unfractionated heparin, intravenous (64.3%), subcutaneous (16.7%) or low molecular weight heparin (17.1%) administration, followed by warfarin. Twelve patients died before discharge from the hospital, due to causes not related to pulmonary embolism. The remaining 40 patients were followed-up for a period of 3 months to 10 years. Two died of causes not related to pulmonary embolism, one developed post-thrombotic sequels, such as residual edema and limitations to upper limb movement, and six had discrete residual symptoms (edema and pain). Conclusions: Upper-extremity deep vein thrombosis was more frequent in patients submitted to venous access and with active neoplasia. The outcome of patients exclusively treated with oral anticoagulant was at least similar to other treatments proposed in the literature.

Experiência preliminar com novo filtro de veia cava: resultados de 15 implantes

This study presents preliminary results obtained from a new permanent filter, based on Greenfields filter design, with prolongations on three of six struts to stabilize it centrally in the vena caval lumen. The preliminary clinical evaluation of the filter with regard to feasibility, efficacy and safety is reported. From August 2004 to December 2006, 15 vena cava filters were deployed in nine men and six women, who ranged in age from 38 to 79 years (mean, 57.8 years). The approach used was always transjugular. Indications for filter placement were proximal deep venous thrombosis with a contraindication to anticoagulation in 12 patients; hemorrhagic complications with anticoagulation in two patients; and pulmonary embolism, despite adequate anticoagulation in one patient. New vena cava filters were evaluated for releasing, tilting, malpositioning and caval perforation. Follow-up included assessment of access site thrombosis and filter migration, recurrent venous thromboembolism, and caval thrombosis by duplex ultrasound. No patient received anticoagulants in the follow-up. In all patients the filter was successfully released, with no malpositioning, tilting, perforation or access thrombosis. The patients were followed for 3 to 23 months (mean = 11 months). No patient developed recurrent venous thromboembolism. No other patients developed inferior vena cava thrombosis or filter migration. Death occurred in seven patients, all related to baseline illness. This preliminary study suggests good feasibility and safety of the new filter up to the observation period.