Double outlet right ventricle with anterior and left-sided aorta and subpulmonary ventricular septal defect

Double outlet right ventricle (DORV) is a heterogeneous group of abnormal ventriculoarterial connections where, by definition, both great arteries (pulmonary artery and aorta) arise primarily from the morphologically right ventricle. This condition affects 1-1.5% of the patients with congenital heart diseases, with a frequency of 1 in each 10,000 live births. We report the case of an 18-day-old infant with DORV and extremely rare anatomical features, such as anterior and left-sided aorta and subpulmonary ventricular septal defect (VSD). In addition to the anatomic features, the role of the echocardiogram for guiding the diagnosis and the surgical therapy of this congenital heart disease are discussed.

End-systolic pressure-diameter relation of the left ventricle during transient and sustained elevations of blood pressure

OBJECTIVE: To assess the effect of transient and sustained variations in cardiac load on the values of the end-systolic pressure-diameter relation (ESPDR) of the left ventricle. METHODS: We studied 13 dogs under general anesthesia and autonomic blockade. Variations of cardiac loads were done by elevation of blood pressure by mechanical constriction of the aorta. Two protocols were used in each animal: gradual peaking and decreasing pressure variation, the "transient arterial hypertension protocol" (TAH), and a quick and 10 min sustained elevation, the "sustained arterial hypertension protocol"(SAH). Then, we compared the ESDR in these two situations. RESULTS: Acute elevation of arterial pressure, being it "transitory" or "sustained", did not alter the heart frequency and increased similarly the preload and after load. However, they acted differently in end systolic pressure-diameter relation. It was greater in the SAH than TAH protocol, 21.0±7.3mmHg/mm vs. 9.2±1.2mmHg/mm (p<0.05). CONCLUSION: The left ventricular ESPDR values determined during sustained pressure elevations were higher than those found during transient pressure elevations. The time-dependent activation of myocardial contractility associated with the Frank-Starling mechanism is the major factor in inotropic stimulation during sustained elevations of blood pressure, determining an increase in the ESPDR values.

Ambulatory blood pressure monitoring and microalbuminuria in normotensive subjects with insulin-dependent diabetes mellitus

OBJECTIVE: To assess the association between microalbuminuria with ambulatory blood pressure monitoring in normotensive individuals with insulin-dependent diabetes mellitus. METHODS: Thirty-seven patients underwent determination of the rate of urinary excretion of albumin through radioimmunoassay and ambulatory blood pressure monitoring. Their mean age was 26.5±6.7 years, and the mean duration of their disease was 8 (1-34) years. Microalbuminuria was defined as urinary excretion of albumin > or = 20 and <200µg/min in at least 2 out of 3 urine samples. RESULTS: Nine (24.3%) patients were microalbuminuric. Ambulatory blood pressure monitoring in the microalbuminuric patients had higher mean pressure values, mainly the systolic pressure, during sleep as compared with that in the normoalbuminuric patients (120.1±8.3 vs 110.8±7.1 mmHg; p=0.007). The pressure load was higher in the microalbuminuric individuals, mainly the systolic pressure load during wakefulness [6.3 (2.9-45.9) vs 1.6 (0-16%); p=0.001]. This was the variable that better correlated with the urinary excretion of albumin (rS=0.61; p<0.001). Systolic pressure load >50% and diastolic pressure load > 30% during sleep was associated with microalbuminuria (p=0.008). The pressure drop during sleep did not differ between the groups. CONCLUSION: Microalbuminuric normotensive insulin-dependent diabetic patients show greater mean pressure value and pressure load during ambulatory blood pressure monitoring, and these variables correlate with urinary excretion of albumin.

Surgical repair of a pseudoaneurysm of the ascending aorta after aortic valve replacement

We report the case of a patient with a pseudoaneurysm of the ascending aortic clinically diagnosed 5 months after surgical replacement of the aortic valve. Diagnosis was confirmed with the aid of two-dimensional echocardiography and helicoidal angiotomography. The corrective surgery, which consisted of a reinforced suture of the communication with the ascending aorta after opening and aspiration of the cavity of the pseudoaneurysm, was successfully performed through a complete sternotomy using extracorporeal circulation, femorofemoral cannulation, and moderate hypothermia, with no aortic clamping.

Influence of ischemic preconditioning in myocardial protection in patients undergoing myocardial revascularization with intermittent crossclamping of the aorta. Analysis of ions and blood gases

OBJECTIVE: To test the hypothesis that short periods of ischemia may increase the myocardial protection obtained with intermittent crossclamping of the aorta. METHODS: In the control group (18 patients), surgery was performed with systemic hypothermia at 32ºC and intermittent crossclamping of the aorta. Extracorporeal circulation was used. In the preconditioning group (17 patients), 2 crossclampings of the aorta lasting 3min each were added prior to the intermittent crossclamping of the conventional technique with an interval of 2min of reperfusion between them. Blood samples for analyses of pH, pCO2, pO2, sodium, potassium, calcium, and magnesium were obtained from the coronary sinus at the beginning of extracorporeal circulation (time 1), at the end of the first anastomosis (time 2), and at the end of extracorporeal circulation (time 3). RESULTS: No difference was observed in the results of the 2 groups, except for a variation in the ionic values in the different times of blood withdrawal; sodium values, however, remained stable. All patients had a good clinical outcome. CONCLUSION: The results of intermittent crossclamping of the aorta with moderate hypothermia were not altered by the use of ischemic preconditioning.

Proteomic analysis of nitrate-dependent acetone degradation by Alicycliphilus denitrificans strain BC

Alicycliphilus denitrificans strain BC grows anaerobically on acetone with nitrate as electron acceptor. Comparative proteomics of cultures of A. denitrificans strain BC grown on either acetone or acetate with nitrate was performed to study the enzymes involved in the acetone degradation pathway. In the proposed acetone degradation pathway, an acetone carboxylase converts acetone to acetoacetate, an AMP-dependent synthetase/ligase converts acetoacetate to acetoacetyl-CoA, and an acetyl-CoA acetyltransferase cleaves acetoacetyl-CoA to two acetyl-CoA. We also found a putative aldehyde dehydrogenase associated with acetone degradation. This enzyme functioned as a -hydroxybutyrate dehydrogenase catalyzing the conversion of surplus acetoacetate to -hydroxybutyrate that may be converted to the energy and carbon storage compound, poly--hydroxybutyrate. Accordingly, we confirmed the formation of poly-?-hydroxybutyrate in acetone-grown cells of strain BC. Our findings provide insight in nitrate-dependent acetone degradation that is activated by carboxylation of acetone. This will aid studies of similar pathways found in other microorganisms degrading acetone with nitrate or sulfate as electron acceptor.

Anomalous origin of the left pulmonary artery from the ascending aorta: successful surgical correction in an infant with fallot's tetralogy

We describe the case of a 40-day-old female patient with a history of breathlessness since birth who was referred to our hospital for surgical correction of common arterial trunk. The invasive investigation disclosed a Fallot¢s tetralogy anatomy associated with an anomalous origin of the left pulmonary artery from the ascending aorta. Immediately after diagnosis, the patient underwent a successful total surgical correction of the defect, including simultaneous anastomosis of the left pulmonary artery to the pulmonary trunk.

Aspergillus infection in the ascending aorta of a patient with aortic and mitral valve prostheses

We report the case of implantation of metallic mitral and aortic valve prostheses 6 months earlier, with subsequent multiple embolic episodes. The anatomicopathological examination of the thrombus of the third embolic episode was compatible with Aspergillus sp, which was treated with amphotericin B, followed by oral itraconazole. On the fourth embolism, vegetations were visualized in the ascending aorta on echocardiography and resonance imaging, and the patient underwent replacement of the aortic segment by a Haemashield tube and exploration of the aortic prosthesis, which was preserved, because no signs of endocarditis were found. Four months later, the patient died due to cardiogenic shock secondary to acute myocardial infarction caused by probable coronary embolism and partial dysfunction of the aortic prosthesis.

Tratamento cirúrgico da coarctação de aorta pela aortoplastia trapezoidal

OBJETIVO: A aortoplastia trapezoidal é uma variante técnica da anastomose término-terminal que, amparada em elementos da geometria, objetiva aumentar o diâmetro da aorta ao nível da sutura reduzida e, consequentemente, a manutenção de gradientes pressóricos residuais ou recorrentes indesejáveis a curto e a longo prazo. MÉTODOS: Após a ressecção da área coarctada e tecido ductal, são confeccionados em cada coto aórtico 3 trapezóides que, ao serem confrontados, criam linha de sutura com aspecto sinusoidal (zigue-zague). Foram operados por esta técnica 33 pacientes, a maioria homens, com idades variando de 3 meses a 36 anos (m 9,5 ± 9,7). RESULTADOS: Não ocorreu mortalidade imediata ou tardia e o tempo de evolução a longo prazo foi de 1,1 a 7,6 anos (m 3,6 ± 3,4). A maioria dos pacientes ficou assintomática com níveis normais de pressão arterial, possibilitando a descontinuação da terapêutica antihipertensiva (p<0,0001). Constatou-se importante redução dos gradientes pressóricos observados ao ecodopplercardiograma e ao cateterismo cardíaco (p<0,001). A análise das imagens das aortografias mostrou boa continuidade anatômica na região da anastomose e o estudo morfométrico da aorta revelou efeitos benéficos do método traduzidos pelo aumento do calibre da aorta no segmento distal do arco, istmo e porção descendente. CONCLUSÃO: A aortoplastia trapezoidal mostrou resultados clínicos satisfatórios que autorizam sua aplicação em todos os casos de anastomose término-terminal indicados.

Associação entre o efeito de contraste espontâneo na aorta torácica e eventos isquêmicos encefálicos recentes. Estudo através do ecocardiograma transesofágico

OBJETIVO: Avaliar a existência de associação independente entre a presença de efeito de contraste espontâneo na aorta e eventos isquêmicos encefálicos recentes. MÉTODOS: Estudados com ecocardiograma transesofágico 224 indivíduos com diagnóstico de eventos isquêmicos encefálicos recente 5 e 85 controles que realizaram o exame por diversas doenças cardíacas presentes/suspeitas, sendo pesquisado a presença do efeito de contraste na aorta e de outras potenciais fontes emboligênicas cardíacas associadas. Um questionário sobre os fatores de risco clínicos para eventos isquêmicos encefálicos foi coletado no momento do exame. RESULTADOS: O efeito de contraste na aorta apresentou associação com eventos isquêmicos encefálicos (RC=2,83; IC 95%, 1,65-4,46; P<0,001), na análise bivariada. Na análise multivariada, permaneceu associado a eventos isquêmicos encefálicos recentes (RC=2,05; IC 90%, 1,10-3,85 ; P=0,06). A idade > 60 anos, história de hipertensão arterial sistêmica, história de tabagismo e de dislipidemia foram fatores de risco associados independentemente ao efeito de contraste na aorta. A presença de efeito de contraste espontâneo no átrio esquerdo e a de excrescências de Lambl foram fatores ecocardiográficos associados independentemente ao efeito de contraste na aorta. CONCLUSÃO: O efeito de contraste na aorta esteve associado, de forma independente, aos eventos isquêmicos encefálicos recentes, bem como seus fatores de risco clínicos. Estes resultados vêm reforçar a hipótese de que o fenômeno é um marcador de múltiplos fatores de risco.

Infecção de prótese vascular em cirurgia da aorta torácica: revisão da experiência e relato de caso tratado por técnica não convencional

Relatamos o caso de uma paciente de 37 anos de idade, que há cinco anos havia sido submetida à operação de Bental-de Bono em nosso serviço e retornou com dor de forte intensidade no toráx, sendo diagnosticada dissecção aguda de aorta do tipo III e tratada clinicamente. Um ano após esse episódio houve expansão dessa dissecção e a paciente foi submetida à cirurgia com interposição de prótese de dacron em aorta descendente. No pós-operatório imediato houve broncopneumonia esquerda e a paciente recebeu alta em boas condições e afebril. Após um mês da alta, retornou com febre e toxemia. Com diagnóstico de empiema pleural, foi submetida à toracotomia exploradora que não confirmou esse diagnóstico, havendo apenas intenso espessamento pleural. Quatro meses após a toracotomia exploradora, foram isolados Klebsiella pneumoniae e Enterobacter sp na hemocultura. A ressonância magnética revelou imagens compatíveis com infecção peri-prótese. Com esse quadro clínico e laboratorial foi indicada a remoção do enxerto e derivação axilo-bifemoral. A operação foi realizada com sucesso, a paciente recebeu alta em boas condições e continua fazendo controle ambulatorial e, atualmente, encontra-se com 57 meses de evolução sem complicações. São discutidos os métodos empregados para o diagnóstico e tratamento da infecção de prótese na cirurgia da aorta torácica.