Percutaneous endovascular delivery of calcium chloride to the intact porcine carotid artery: A novel animal model of arterial calcification.

OBJECTIVE: The present study evaluated the effect of endovascular administration of calcium chloride to the carotid artery of swines, to create a model of arterial calcification. METHODS: Fifteen Large White pigs were used for the study. Via endovascular treatment, carotid arteries were exposed during 9 min to either calcium chloride (experimental artery) or saline (control artery) with the use of the TAPAS catheter. Intravascular ultrasound (IVUS) imaging was obtained at baseline, postprocedure and at 30 days. Optical coherence tomography (OCT) imaging was obtained in vitro after carotids were harvested. Longitudinally cut parallel arterial segments were placed in a system of delicate clamps and underwent uniaxial strain test. All arteries underwent histopathological examination. RESULTS: Calcium chloride treated segments showed extensive circumferential parietal calcification evident on both IVUS and OCT. Reduction in minimal lumen area on IVUS was evident in experimental arteries both at 24 hr and 30 days postprocedure. Histopathologic assessment (Von Kossa stain) confirmed medial calcification with mild intimal thickening. Biomechanical testing showed treated segments to have smaller breaking strength and less elastic deformation than controls. CONCLUSION: We developed a nonexpensive, reproducible model of early carotid medial calcification in pigs. Our model has the potential to help the development of research to unravel mechanisms underlying arterial calcification, the use of current or new devices to treat calcified lesions as well as to serve as an option for training interventionalists on the use of such devices.

Endovascular model of abdominal aortic aneurysm induction in swine.

Abdominal aortic aneurysms are among the main causes of death. The high morbidity and mortality associated with aneurysm rupture and repair represents a challenge for surgeons and high risk for patients. Although experimental models are useful to understand, train, and develop new treatment and diagnostic methods for this pathology, animal models developed to date are far from ideal. Animals are either too small and do not represent the pathology of humans, or the procedures employ laparotomy, or the aortic behavior does not resemble that of a true aneurysm. We developed a novel, less invasive and effective method to induce true aortic aneurysms in Large White pigs. Animals were submitted to an endovascular chemical induction using either calcium chloride (25%) or swine pancreatic elastase. Controls were exposed to saline solution. All animals were operated on using the same surgical technique under general anesthesia. They were followed weekly with ultrasound examinations and at 4 weeks the aorta was harvested. Although elastase induced only arterial dilation, imaging, histological, and biomechanical studies of the aorta revealed the formation of true aneurysms in animals exposed to calcium chloride. Aneurysms in the latter group had biomechanical failure properties similar to those of human aneurysms. These findings indicate that the endovascular approach is viable and does not cause retroperitoneal fibrosis.

Inner tubing technique used for the treatment of anastomotic aneurism.

The authors report the case of a 66-year-old male patient diagnosed with a pseudoaneurysm of the distal aorto-aortic anastomosis treated with the inner tubing technique. The patient had been operated on 1 year before when he had an aortic prosthesis implanted as treatment for a ruptured abdominal aortic aneurysm. The inner tubing technique was developed to facilitate the treatment in bifurcated vascular lesions, where endovascular conventional prosthesis is not available.

Feeding tube replacement: not always that simple!

Although surgical gastrostomy is not a technically troublesome surgery, the procedure may be accompanied by unfavorable outcomes. Most complications occur early in the post-operative period and include feeding tube dislodgment, stomal infection, peritonitis, and pneumonia. The authors report the case of an 83-year-old man who underwent a surgical gastrostomy because of a swallowing disorder after an ischemic stroke. Nine months after the procedure, the feeding tube dislodged and a new tube was inserted with a certain delay and with some difficulty, causing a false path and consequently an intrabdominal abscess after diet infusion. The outcome was fatal. The authors call attention for meticulous care with the insertion of feeding tubes and advise the performance of imaging control to assure its precise positioning.

Ring-stripping retrograde common carotid endarterectomy: case report.

CONTEXT: Total occlusion of the common carotid is rare and the indications and techniques for surgical treatment are still a matter of controversy. OBJECTIVE: To demonstrate the feasibility of retrograde common carotid endarterectomy. DESIGN: Retrospective case report study. SETTING: Tertiary care private hospital. PARTICIPANTS: Three patients underwent ring-stripping retrograde common carotid endarterectomy. Their ages were 81, 68 and 65 years. All were hypertensive with generalized atherosclerosis, two had diabetes mellitus, and one had undergone coronary artery bypass some years earlier and had non-dialytic chronic renal insufficiency. Symptoms of brain ischemia were present in two patients. All patients had total occlusion of the common carotid, extending from the origin to the bifurcation and localized in the right common carotid in two cases. In two cases the internal carotid artery was also occluded. MAIN MEASUREMENTS: Postoperative early mortality and stroke rate, and the medium and long-term endarterectomy patency. RESULTS: There were no deaths. One patient had a transient ischemic attack. All endarterectomies were patent after eight months, four years and seven years of follow-up. CONCLUSION: There is low mortality, and the procedure can be done through only one cervical incision. Tandem lesions of the carotid arteries can be treated together. It is suitable for long total occlusions of the common carotid, and long-term patency.

Indução de aneurisma em aorta abdominal de porcos: um modelo endovascular / Endovascular model of abdominal aortic aneurysm induction in swine

A ruptura do aneurisma da aorta abdominal está entre as principais causas de óbito. A alta morbi-mortalidade associada à ruptura e tratamento dos aneurismas representa um grande desafio aos médicos e um alto risco aos pacientes. Apesar dos modelos experimentais serem úteis para compreendermos, treinarmos, testar novos métodos diagnósticos e terapêuticos para esta doença, os modelos existentes até o momento ainda não são os ideais. Nos modelos existentes, os animais são muito pequenos e não representam a doença nos humanos, ou o procedimento envolve laparotomia, ou o comportamento do aneurisma criado não é semelhante ao de um aneurisma verdadeiro. Desenvolvemos, a partir de uma abordagem minimamente invasiva, um método eficiente de induzirmos a formação de um aneurisma verdadeiro na aorta abdominal infrarrenal de porcos Large White. Os animais foram submetidos a indução química a partir de uma aplicação por via endovascular de cloreto de cálcio a 25% ou elastase pancreática suína. Os animais controles foram submetidos a tratamento com soro fisiológico (NaCl 0,9%). Todos os animais foram submetidos à mesma técnica operatória, sob anestesia geral. Os animais foram acompanhados com exames ultrassonográficos com Doppler semanalmente, e as aortas colhidas para testes biomecânicos e análise histológica após 4 semanas. Apesar das aortas tratadas com elastase apresentarem apenas dilatação, estudos de imagens, histológicos e biomecânicos mostraram que as aortas tratadas com cloreto de cálcio evoluíram para aneurismas verdadeiros, com comportamento biomecânico semelhante ao dos aneurismas de humanos. Estes resultados/achados indicam que a abordagem endovascular para a indução de aneurisma é factível e não ocasiona uma fibrose retroperitoneal.

Abdominal aortic aneurysms rupture are among the main causes of death. The high morbidity and mortality associated with aneurysm rupture and repair represents a challenge for surgeons and high risk for patients. Although experimental models are useful to understand, train, and develop new treatment and diagnostic methods for this disease, animal models developed to date are far from ideal. Animals are either too small and do not represent the pathology of humans, or the procedures employ laparotomy, or the aortic behavior does not resemble that of a true aneurysm. We developed a novel, less invasive and effective method to induce true aortic aneurysms in Large White pigs. Animals were submitted to an endovascular chemical induction using either calcium chloride (25%) or swine pancreatic elastase. Controls were exposed to saline solution. All animals were operated on using the same surgical technique under general anesthesia. They were followed weekly with ultrasound examinations and at 4 weeks the aorta was harvested. Although elastase induced only arterial dilation, imaging, histological, and biomechanical studies of the aorta revealed the formation of true aneurysms in animals exposed to calcium chloride. Aneurysms in the latter group had biomechanical failure properties similar to those of human aneurysms. These findings indicate that the endovascular approach is viable and does not cause retroperitoneal fibrosis.

Aortofemoral thromboendarterectomy.

PURPOSE: To study whether endarterectomy is feasible in all patients with aortofemoral atherosclerotic obstruction, considering early and late results. METHODS: A clinical, prospective, and descriptive study carried out in a university hospital. Inclusion criteria were atherosclerotic aortofemoral obstructive disease, clinical status compatible with major surgery, and absence of prior restorative procedure. Exclusion criteria were aneurysm, inflammatory arterial disease, and prior restorative procedure found during surgery. Eighty patients entered the protocol, but 9 were excluded (11.2%). Seventy-one patients, mean age of 57.3 years, underwent endarterectomy. Operative indications were intermittent claudication and critical ischemia. A ring-stripper endarterectomy technique was employed in all patients. Results were related to age, gender, symptoms, presence of diabetes mellitus, extension of endarterectomy, and extent of obstructive disease. Chi square or Fisher exact tests were used when appropriate, and the Wilkoxon (Gehan) test was used to compare survival curves. RESULTS: Sixty-eight (100%) endarterectomies were patent at discharge. The mortality rate was 4.2%. The amputation rate (4.3%) was higher in diabetic patients and when there was associated femoropopliteal obstruction. The 5-year survival rate was 83.3%, and late deaths were mostly cardiovascular. Diabetes mellitus, age above 65 years, and associated femoropopliteal obstruction lowered the survival rate. The 5-year patency rate was 87.0%. Critical ischemia and less extensive endarterectomies were associated with a lower patency rate. There were no anastomotic aneurysms or deep infections. CONCLUSIONS: Aortofemoral thromboendarterectomy is feasible in 90% of patients, early mortality rate is low, diabetic patients and those with associated femoropopliteal obstructive disease have a higher mortality rate, amputation rate is low, late deaths are mostly cardiovascular, and late patency rate is high, and even higher in the intermittent claudication group.

Inner tubing endograft: a new technique for bifurcation preservation / Inner tubing: uma nova técnica para preservação de bifurcações

Treating narrow arteries and their bifurcations is a major challenge to the endovascular surgeon. We describe a new endovascular technique that was used to treat a narrow aorta and that may also be used to preserve other bifurcations. Using three straight stents may enable the endovascular surgeon to treat bifurcation while maintaining flow to both distal arteries.

O tratamento de artérias de pequeno calibre e suas bifurcações é um grande desafio para o cirurgião endovascular. Descrevemos uma nova técnica endovascular que foi usada no tratamento de uma aorta de pequeno calibre e que também pode ser usada para preservar outras bifurcações. O uso de três stents retos pode permitir ao cirurgião endovascular o tratamento de bifurcação mantendo o fluxo em ambas as artérias distais.

Tratamento endoluminal de aneurismas anastomóticos na aorta abdominal: relato de dois casos / Endovascular treatment of abdominal aortic anastomotic aneurysms: report of two cases

Os aneurismas anastomóticos que envolvem a anastomose proximal de reconstruções do território aorto-ilíaco são graves, e as operações convencionais para sua correção são complexas e passíveis de graves complicações. Apresentamos dois casos de aneurismas de anastomoses proximais de enxerto aorto-bifemoral que ocorreram após 15 e 18 anos, respectivamente, de evolução dos enxertos e que foram corrigidos pela técnica endoluminal. Ambos os pacientes evoluíram bem e foram submetidos a controle pela tomografia computadorizada com 12 e 6 meses de evolução, respectivamente, com exclusão do aneurisma.

Ring-stripping retrograde common carotid endarterectomy: case report

CONTEXT: Total occlusion of the common carotid is rare and the indications and techniques for surgical treatment are still a matter of controversy. OBJECTIVE: To demonstrate the feasibility of retrograde common carotid endarterectomy. DESIGN: Retrospective case report study. SETTING: Tertiary care private hospital. PARTICIPANTS: Three patients underwent ring-stripping retrograde common carotid endarterectomy. Their ages were 81, 68 and 65 years. All were hypertensive with generalized atherosclerosis, two had diabetes mellitus, and one had undergone coronary artery bypass some years earlier and had non-dialytic chronic renal insufficiency. Symptoms of brain ischemia were present in two patients. All patients had total occlusion of the common carotid, extending from the origin to the bifurcation and localized in the right common carotid in two cases. In two cases the internal carotid artery was also occluded. MAIN MEASUREMENTS: Postoperative early mortality and stroke rate, and the medium and long-term endarterectomy patency. RESULTS: There were no deaths. One patient had a transient ischemic attack. All endarterectomies were patent after eight months, four years and seven years of follow-up. CONCLUSION: There is low mortality, and the procedure can be done through only one cervical incision. Tandem lesions of the carotid arteries can be treated together. It is suitable for long total occlusions of the common carotid, and long-term patency

Early and late results of carotid endarterectomy: retrospective study of 70 operations

CONTEXT: Indications and results of carotid endarterectomy have been defined from clinical multicentric trials like the European Carotid Surgery Trialists, North-American Symptomatic Carotid Endarterectomy Trial and Asymptomatic Carotid Atherosclerosis Study. The patients included in these trials were highly selected, as were the surgeons performing the operations. Clinical practice is different but the same results should be achieved. OBJECTIVE: To study indications, technique, early and late results, and whether carotid endarterectomy has been performed in accordance with standards defined by multicentric trials. DESIGN: Retrospective case report study. SETTING: A tertiary care private hospital. PARTICIPANTS: 57 patients, on whom 70 carotid endarterectomies were performed over a 10-year period. The median age was 66.4 ± 7.8 years; 43 (75.4 percent) were male, 41 (71.9 percent) hypertensive, 36 (63.1 percent) current smokers and 24 (21.0 percent) had diabetes. Bilateral carotid stenosis was present in 31 (54.3 percent) patients, peripheral arterial occlusions in 32 (56.1 percent) and ischemic cardiopathy in 25 (43.1 percent). All patients had had angiography and 41 (71.9 percent) had also had a duplex-scan of neck arteries. Cerebral imaging via computerized tomography scan or magnetic resonance imaging was obtained for 36 patients. Patients were followed up over a period of one to 122 months. MAIN MEASUREMENTS: early and late post-operative death, early and late post-operative stroke, and recurrence of atheroma plaque and symptoms relative to carotid stenosis. RESULTS: There was one post-operative death (1.4 percent) caused by myocardial infarction and two early strokes (2.8 percent): a total complication rate of 4.2 percent. After 3 and 5 years, 95.4 percent and 81.3 percent of patients respectively were stroke-free and 72.8 percent and 67.3 percent were alive. There were four recurrences and two of them related to stroke. Forty-nine (70 percent) stenoses operated on were symptomatic. Brain infarction was detected in 59.2 percent of patients who underwent computerized tomography scan or magnetic resonance imaging. CONCLUSIONS: Carotid endarterectomy was done in accordance with international standards. The most frequent cause of late death was myocardial infarction, and recurrences were related to stroke. Patients should be followed up closely

Cirurgia Endoscópica Subfascial de veias Perfurantes Insuficientes (CESPI): experiência inicial / Subfascial endoscopic perforator venous surgery: initial experience

OBJETIVO: Estudar os resultados imediatos e a médio prazo da cirurgia endoscópica subfascial de perfurantes. MÉTODO: Estudo clínico, prospectivo e descritivo. Critérios de inclusão: insuficiência venosa crônica primária ou secundária, sistema venoso profundo pérvio e índice tornozelo/braço maior que 0,8. Critérios de exclusão: ocorrência da trombose venosa profunda, ou trauma ou cirurgia ortopédica e cirurgia sobre o sistema venoso profundo durante o período de seguimento pós-operatório. Todos doentes foram examinados pelo ecodoppler colorido antes da operação. RESULTADOS: Foram operados 43 membros a partir de junho/1997. Eram 27 doentes com média de idade 56,5 anos. A insuficiência venosa crônica era secundária à trombose venosa em dois membros. Três membros foram classificados como C3, 15 como C4, 11 como C5 e 14 como C6. A retirada das veias safena interna, safena externa e tributárias foi associada em 35 membros. Foram ligadas três a cinco perfurantes por membro; não houve óbitos no pós-operatório imediato; houve três infecções e as úlceras cicatrizaram em períodos variáveis de duas a 15 semanas. Dezenove doentes obtiveram alta hospitalar no primeiro dia de pós-operatório, seis no segundo e dois no terceiro. Houve uma recidiva de úlcera (4,0 por cento) durante o período de seguimento de 25 meses (média) por causa de perfurante não-ligada. CONCLUSÕES: A cirurgia endoscópica subfascial de veias perfurantes insuficientes associada à cirurgia radical de varizes é segura, acompanha-se de baixo índice de complicações, pode ser adaptada aos instrumentos comuns da cirurgia laparoscópica, indicada para doentes classificados como C4, C5 e C6 e se acompanha de bons resultados imediatos e a médio prazo.

BACKGROUND: Prevalence of varicose ulcers in Brazil has been estimated as high as 3.6 percent. Perforator vein insufficiency is the main source for the development of these ulcers. The recently proposed SEPS technique is regarded as minimally invasive approach followed by low complication rates and short in-hospital stay. Our objective is to study the results of subfascial endoscopic perforator surgery associated or not to superficial venous system surgery. METHODS: Prospective, non-controlled ,clinical study. Inclusion criteria were patent deep venous system, patient with primary or secondary venous insufficiency (congenital not included) and an ankle/arm index higher than 0.8; exclusion criteria were: deep vein thrombosis, trauma or orthopedic surgery and deep venous system surgery occurring during post-operative follow-up. All patients had a duplex-scan perfomed before operation. RESULTS: Forty-three lower limbs were operated on since june/97; there were 27 patients with mean age 56.6 years; great saphenous vein, lesser saphenous vein and tributaries stripping were associated in 29 limbs; three limb were classified as C3, 15 as C4, 11 as C5 and 14 as C6. Venous insufficiency was secondary to deep venous thrombosis in 2 limbs. There were no immediate deaths; three to five perforators per limb were ligated; all ulcers healed during a period from two to 15 weeks; there were three infections (6.9 percent); 19 patients left hospital on 1st, six on 2nd and two on 3rd post-operative day. There was one ulcer recurrence (4.0 percent) after 10 months (perforator vein left in place). CONCLUSION: the procedure is safe, the hospitalization time is short, ulcer healing occurs mostly within two weeks and recurrence rate depends on a follow-up period at least of five years.

Aortofemoral thromboendarterectomy

PURPOSE: To study whether endarterectomy is feasible in all patients with aortofemoral atherosclerotic obstruction, considering early and late results. METHODS: A clinical, prospective, and descriptive study carried out in a university hospital. Inclusion criteria were atherosclerotic aortofemoral obstructive disease, clinical status compatible with major surgery, and absence of prior restorative procedure. Exclusion criteria were aneurysm, inflammatory arterial disease, and prior restorative procedure found during surgery. Eighty patients entered the protocol, but 9 were excluded (11.2 percent). Seventy-one patients, mean age of 57.3 years, underwent endarterectomy. Operative indications were intermittent claudication and critical ischemia. A ring-stripper endarterectomy technique was employed in all patients. Results were related to age, gender, symptoms, presence of diabetes mellitus, extension of endarterectomy, and extent of obstructive disease. Chi square or Fisher exact tests were used when appropriate, and the Wilkoxon (Gehan) test was used to compare survival curves. RESULTS: Sixty-eight (100 percent) endarterectomies were patent at discharge. The mortality rate was 4.2 percent. The amputation rate (4.3 percent) was higher in diabetic patients and when there was associated femoropopliteal obstruction. The 5-year survival rate was 83.3 percent, and late deaths were mostly cardiovascular. Diabetes mellitus, age above 65 years, and associated femoropopliteal obstruction lowered the survival rate. The 5-year patency rate was 87.0 percent. Critical ischemia and less extensive endarterectomies were associated with a lower patency rate. There were no anastomotic aneurysms or deep infections. CONCLUSIONS: Aortofemoral thromboendarterectomy is feasible in 90 percent of patients, early mortality rate is low, diabetic patients and those with associated femoropopliteal obstructive disease have a higher mortality rate, amputation rate is low, late deaths are mostly cardiovascular, and late patency rate is high, and even higher in the intermittent claudication group

Ferimentos da artéria subclávia. Estudo retrospectivo de 20 casos / Subclavian artery trauma

Objetivo: Análise de 20 casos quanto à casuística, etiologia, lesões associadas, tipos de tratamento e evolução das lesões traumáticas traumáticas da artéria subclávia, no período de janeiro de 1997 a dezembro de 2001. Métodos: Estudo retrospectivo por levantamento de prontuários no serviço de arquivo médico do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP). Termos pesquisados: lesão de subclávia, pseudo-aneurisma de subclávia e fístula arteriovenosa de subclávia. Resultados: Foram analisados 77 prontuários, dos quais 20 se enquadravam em lesões desses ramos...

Oclusão tardia das artérias renais após a correção endovascular dos aneurismas da aorta abdominal com próteses de fixação supra-renal / Late occlusion of renal arteries after endovascular repair of abdominal aortic aneurysms by suprarenal fixation of stent grafts

Objetivo: Apresentar três casos em que se observaram complicações tardias nas artérias renais. Casuística e método: No período de novembro de 1998 a fevereiro de 2005, foram operados, pelo Centro Paulista de Cirurgia Vascular, 121 pacientes com aneurima de aorta abdominal pelo método endovascular. Em 81 pacientes, a endoprótese foi fixada na posição supra-renal e, em 40, a fixação foi infra-renal. Os pacientes foram acompanhados no pós-operatório com tomografia abdominal realizada com 1, 6 e 12 meses anualmente, a partir do primeiro ano. Noventa e sete pacientes (80,1 por cento) foram acompanhados dentro desse protocolo, sem perda do seguimento. Destes, 33 (34 por cento) apresentavam fixação infra-renal e 64 (66 por cento) fixação supra-renal...

Restauração de sistema venoso profundo associada a cirurgia endoscópica subfascial de perfurantes insuficientes / Reconstruction of the deep venous system associated with subfascial endoscopic perforator surgery (SEPS)

Relato de caso e demonstração de que o diagnóstico completo e a associação de técnicas terapêuticas adequadas são fundamentais. Os autores relatam o caso de um paciente de 37 anos, do sexo masculino, apresentando trauma de veia femoral esquerda, que havia sido ligada há 8 anos e não apresentava edema e úlceras recorrentes de perna. A flebografia identificou uma interrupção da veia femoral abaixo da junção com a safena. Realizou-se anastomose entre safena e veia poplítea acima do joelho. A úlcera cicatrizou e recidivou após 2 anos. A ultra-sonografia Doppler demonstrou quatro perfurantes insuficientes e anastomose safena-poplítea pérvia. Após cirurgia endoscópica subfascial de perfurantes insuficientes, a úlcera cicatrizou. Não houve recidiva após período de seguimento de 4 anos. Conclui-se ser importante a realização de diagnóstico completo, assim como a associação de várias técnicas terapêuticas.

Indução de aneurisma em aorta abdominal de rato / Experimental model of aortic aneurysm in rats

O objetivo do trabalho foi criar um modelo experimental animal de indução de aneurisma em aorta abdominal, identificando qual a droga e técnica de escolha, para a pesquisa de patogenia e tempo de desenvolvimento do aneurisma. Foram utilizados 48 ratos Wistar machos adultos, que foram submetidos a laparotomia mediana com aplicação das drogas de forma intraluminal ou periarterial. As drogas utilizadas foram cloreto de cálcio a 0,9 ou 5,0 molar (M) e cloreto de sódio 0,9 por cento ou 7,5 por cento. O trabalho foi realizado em duas etapas, nas quais se preocupou identificar a melhor droga na primeira etapa e a melhor técnica na segunda. Vinte e sete ratos foram divididos em grupos de três animais cada, variando a droga e a metodologia de aplicação na primeira etapa. Na segunda etapa utilizaram-se dois grupos com dez animais em cada, usando-se a solução de cloreto de cálcio a 5,0M com aplicação periarterial ou intraluminal...

Expansão de aneurisma de aorta abdominal após correção endoluminal / Growth of abdominal aortic aneurysm after endoluminal repair

Trata-se do relato de um caso de crescimento de aneurisma da aorta abdominal, após correção endovascular com sucesso, com exclusão de vazamento e baixa pressão no interior do saco aneurismático.Haverá a discussão dos possíveis fatores etiológicos envolvidos, bem como da abordagem terapêutica adotada no caso, com reduçãovolumétrica cirúrgica do saco aneurismático sem substituição da endoprótese.