Therapeutic option for children with esophageal caustic stenosis

Caustic ingestion is a leading cause of esophageal stenosis in children. Herein we report four cases using mitomycin C (MMC), a drug that inhibits cell division, protein synthesis and fibroblast proliferation and has been used as an adjuvant therapy for caustic esophageal stenosis that is recalcitrant to conventional dilation techniques. A retrospective chart review was performed on four pediatric patients with severe, recurrent esophageal stricture after caustic ingestion. The patients had required six to 20 esophageal dilations over a 4-16-month period before MMC application. MMC was applied after an endoscopic dilation on saturated pledgets at a dose of 0.1 mg/mL for 2 min in the area where the strictures had been lyzed. From the four children treated with MMC, two have been asymptomatic for 16 and 20 months and two still require esophageal dilation, however, at longer intervals. All patients have shown satisfactory weight gain with food intake exclusively per oral. Although further studies are required, there is strong evidence that MMC is a safe and effective adjuvant therapy in the treatment of esophageal caustic stenosis. © 2008 The Authors.

The use of mitomycin C in caustic esophagitis in rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological and functional evaluation of distal esophagus of rabbits submitted to esophageal infusion with caustic soda

A ingestão de substâncias cáusticas constitui importante situação de emergência, tendo em vista a gravidade de suas seqüelas. OBJETIVO: Estudar as alterações morfológicas e funcionais do esôfago de coelhos submetidos à infusão esofágica com soda cáustica (NaOH). MÉTODOS: 88 coelhos foram divididos em 4 grupos: G1 (n=22) foi submetido à infusão esofágica com água destilada; G2, G3 e G4 foram submetidos a infusão esofágica com NaOH a 2%, 4% e 6%, respectivamente. Alterações morfológicas foram estudadas em 12 animais de cada grupo e as alterações manométricas, nos 10 animais restantes. Foram feitas análises do esfíncter inferior do esôfago (EIE), número e amplitude das contrações no terço distal do esôfago. Estes estudos foram realizados antes (momento 1 - M1) e aos 30 minutos, 6 horas e 24 horas após a infusão esofágica (momentos M2, M3 e M4, respectivamente). RESULTADOS: Avaliação macroscópica: G1 - sem alterações; G2 - edema, hiperemia e descamação; G3 - aumento do calibre do esôfago, úlceras, descamação da mucosa; G4 - lesões semelhantes as do G3, porém mais intensas, áreas de extensa hemorragia. Avaliação funcional: a pressão no EIE foi mais elevada em M2 no grupo 2; o número das contrações no terço distal do esôfago foi menor em G3 e G4, e a amplitude das contrações foi menor em G4. CONCLUSÕES: 1) a infusão esofágica com NaOH constitui excelente modelo experimental de esofagite cáustica no coelho; 2) a infusão esofágica com NaOH causa lesões na parede do esôfago, com gravidade proporcional a concentração da solução; 3) a infusão causou espasmo do EIE em M2 e redução do número e amplitude das contrações no terço distal do esôfago.

Myocardial contractile dysfunction contributes to the development of heart failure in rats with aortic stenosis

Objectives: To analyze the potential contribution of contractility state and ventricular geometry to the development of heart failure in rats with aortic stenosis.Methods: Rats were divided into three groups: compensated aortic stenosis (AS, n = 11), heart failure AS (n = 12) and control rats (C, n = 13).Results: After 21 weeks, failing AS rats presented higher systolic (C = 36.6 +/- 3.1, AS-78.6 +/- 4.8*, failing AS = 104.6 +/- 7.8*) and diastolic meridian stress (C = 6.9 +/- 0.4, AS = 20.1 +/- 1.1*, failing AS = 43.2 +/- 3.2*(dagger)), hydroxyproline (C = 3.6 +/- 0.7 mg/g, AS = 6.6 +/- 0.6* mg/g, failing AS = 9.2 +/- 1.4*(dagger) mg/g) and cross-sectional area (C = 338 +/- 25 mu m(2), AS = 451 +/- 32* mu m(2), failing AS = 508 +/- 36*(dagger) mu m(2)), in comparison with control and compensated AS animals (*p < 0.05 vs. control, (dagger)p < 0.05 vs. AS). In the isometric contraction study, considering the time from peak tension to 50% relaxation (RT50), the relative variation responses, following post-rest contraction and increase in Ca2+ concentration, were higher in failing AS than compensated AS animals. In contrast, following post-rest contraction, compensated AS group presented higher values of the peak developed tension (DT) than failing AS group. Following beta-adrenergic stimulation, control animals presented higher values of +dT/dt and -dT/dt than AS animals. In addition, failing AS animals presented higher TPT values than compensated AS animals.Conclusion: Myocardial contractile dysfunction contributes to the development of heart failure in rats with aortic stenosis. (c) 2006 Elsevier B.V.. All rights reserved.

Follow-up study of morphology and cardiac function in rats undergoing induction of supravalvular aortic stenosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Frequency of coronary artery disease in patients with renal artery stenosis without clinical manifestations of coronary insufficiency

Atherosclerotic renal artery stenosis (RAS) and coronary artery disease (CAD) arise from the same multiple risk factors. The purpose of this study was to assess the frequency of previously undiagnosed CAD in patients with angiographically confirmed RAS, by conducting coronary arteriography in the same setting. of 57 consecutive patients referred for renal arteriography on clinical grounds during a 14-month period, 28 had no RAS and 6 had RAS, but previously documented CAD. of the remainder 23 patients. 17 (74%; CI 56%-92%) had both RAS and CAD (7 single vessel, 4 two-vessel, and 7 multivessel disease). The clinical characteristics, such as age, blood pressure (BP) levels, signs of heart failure, were no different between those with and without CAD, although the 4 diabetic patients, the 4 patients with fundoscopic findings of grade III retinopathy, 11 of 14 with peripheral arterial disease, and 7 of 8 patients with prior stroke belonged in the CAD group. None developed complications as a result of the two consecutive procedures. The data suggest that in patients with RAS the frequency of silent CAD is high and cannot be predicted on clinical grounds alone, therefore coronary angiography should be routinely recommended in the same setting.

Estenose da fossa intercondilar após estabilização articular com retalho de fáscia lata em cães

Determinaram-se os índices de largura da fossa intercondilar (FI), após transecção do ligamento cruzado cranial em nove cães adultos submetidos à estabilização articular com retalho de fáscia lata. Os joelhos foram alocados em dois grupos, sendo o joelho direito (GI) submetido à incisuroplastia troclear (ITR) e posterior estabilização articular, e o joelho esquerdo submetido somente à substituição ligamentar (GC). Cada grupo foi dividido em três subgrupos correspondentes aos momentos de eutanásia aos 30, 90 e 180 dias de pós-operatório. Os índices de largura da FI foram determinados, macroscópica e radiograficamente, pela mensuração da abertura cranial da FI nos terços cranial, médio e caudal, e indexados em relação à largura epicondilar. Observou-se aumento significativo dos índices macroscópicos e radiográficos nas articulações do GI, sendo estes estatisticamente diferentes daqueles das articulações de GC. Não foi observada estenose intercondilar nos joelhos de GC após a estabilização articular. Conclui-se que a estabilização articular com retalho de fáscia lata preveniu a estenose da fossa intercondilar, e que a ITR promoveu o alargamento permanente dessa estrutura.

Extrinsic compression of popliteal artery in asymptomatic athlete and non-athlete individuals - A comparative study using duplex scan (color duplex sonography)

Aim. Extrinsic compression of the popliteal artery and absence of surrounding anatomical abnormalities characterize the functional popliteal artery entrapment syndrome (PAES). The diagnosis is confirmed to individuals who have typical symptoms of popliteal entrapment and occlusion or important stenosis of the popliteal artery with color duplex sonography (CDS), magnetic resonance imaging (MRI) or arteriography during active plantar flexion-extension maneuvers. However, variable result findings in normal asymptomatic subjects have raised doubts as to the validity of these tests. The purpose of this study was to compare the frequency of popliteal artery compression in 2 groups of asymptomatic subjects, athletes and non-athletes.Methods. Forty-two individuals were studied. Twenty-one subjects were indoor soccer players, and 21 were sedentary individuals. Physical activity was evaluated through questionnaires, anthropometric measurements, and cardiopulmonary exercise test. Evaluation of popliteal artery compression was performed in lower limbs with CDS, ankle-brachial index (ABI) measurements and continuous wave Doppler of the posterior tibial artery.Results. The athletes studied fulfilled the criteria of high level of physical activity whereas sedentary subjects met the criteria of low level of activity. Popliteal artery compression was observed with CDS in 6 (14.2%) studied subjects; 2 of whom (4.7%) were athletes and 4 (9.5%) were non-athletes. This difference was not statistically significant (p=0.21). Doppler of the tibial arteries and ABI measurements gave good specificity and sensibility in the identification of popliteal artery compression.Conclusion. The frequency of popliteal artery compression during maneuvers in normal subjects was 14.2% irrespective of whether or not they performed regular physical activities. Both Doppler and ABI showed good agreement with CDS and should be considered in screening popliteal arteries in individuals suspected of PAES.

O bloqueio do sistema renina-angiotensina atenua a remodelação cardíaca de ratos submetidos a estenose aórtica

OBJETIVO: Avaliar o papel do bloqueador dos receptores AT1 e do inibidor da enzima conversora da angiotensina na remodelação cardíaca induzida por estenose aórtica em ratos. MÉTODOS: Ratos Wistar foram divididos em 4 grupos: controle (C, n=13), estenose aórtica (EAo, n=11), EAo com lisinopril, 20 mg/kg/dia (LIS, n=11) e EAo com losartan, 40 mg/kg/dia (LOS, n=9). Os tratamentos foram iniciados 3 dias antes da cirurgia. Após 6 semanas, os animais foram submetidos ao estudo ecocardiográfico, quantificação da concentração de hidroxiprolina e da área seccional (CSA) miocitária do ventrículo esquerdo (VE). RESULTADOS: A EAo induziu aumento da espessura da parede do VE. Os animais LIS e LOS não apresentaram diferença em relação aos animais controles. Os ratos EAo e LIS apresentaram maiores diâmetros do átrio esquerdo que os ratos controles, enquanto nos animais LOS não houve diferença. Os animais com EAo apresentaram maiores valores da porcentagem de encurtamento que os controle. Esse fato não foi modificado com LIS ou LOS. A CSA dos animais do grupo EAo foi maior que a dos controle. Entretanto, o tratamento com LOS e com LIS atenuou o aumento da área induzida pela EAo. A EAo resultou em aumento na concentração de HOP, enquanto o grupo LOS não apresentou diferença em relação ao grupo controle. CONCLUSÃO: O bloqueio do sistema renina-angiotensina, com bloqueador AT1 e com IECA, pode atenuar o desenvolvimento de hipertrofia cardíaca, porém só o bloqueio dos receptores AT1 atenua a fibrose intersticial do VE.