Coronary morphology and conduction system disturbance induced by therapeutic embolization of the coronary septal artery.

BACKGROUND: Percutaneous transluminal septal myocardial alcohol ablation (PTSMAA) is not a procedure without complications. It may produce heart arrhythmias, especially those due to disturbances of atrioventricular (AV) and interventricular (IV) electrical conduction. OBJECTIVE: The goal of this study was to evaluate the relationship between the anatomical patterns of the right coronary artery and the left anterior descending artery (LAD) and to relate them to the AV and IV bundle branch blocks provoked by PTSMAA. METHOD: Twenty patients with obstructive hypertrophic cardiomyopathy resistant to treatment with drugs successfully underwent PTSMAA. Electrocardiographic analyses were done before and after PTSMAA, and the results were compared with the abnormal septal anatomy. RESULTS: The effectiveness of PTSMAA was obtained in 18 (90%) of the 20 patients by ethanolization of the first great septal branch. In the other 2 patients (10%), 2 septal branches underwent alcoholization. First-grade temporary AV block (AVB) was observed in 6 patients (30%). Ten patients experienced severe bradycardia due to total AVB that required a temporary pacemaker, but 3 of the patients (15%) required a permanent pacemaker. Fourteen patients (70%) experienced permanent complete right branch block, and 2 developed incomplete left anterior block and incomplete left posterior block. Six patients presented with no electrical conduction disturbance at all. CONCLUSION: According to the results of the present investigation with the AV node artery derived from the right coronary artery in all cases, complete and permanent AV conduction system blockade occurred after PTSMAA in all types of anatomy regarding the observed LAD.

Dipyridamole and low doses of heparin as a new successful physiopathologic and therapeutic approach in 2 cases of disseminated intravascular coagulation.

UNLABELLED: OPERATIVE: We report 2 cases of disseminated intravascular coagulation (DIC) successfully treated with the combination of the platelet adhesiveness blocker dipyridamole and low doses of intravenous heparin. METHODS: The first patient was a 17-year-old boy with septic arthritis; the second patient was a 12-year-old boy with a liver abscess. Both had hemocultures positive for Staphylococcus aureus. The diagnosis of DIC was defined by clinical signs of septicemia with fever, tachypnea, peripheral vasoconstriction, and low platelet counts (67,000/mm3 and 47,000/mm3, respectively). The second patient also presented with acute ischemia of the fingers and toes. General care was provided in the intensive care unit, and high doses of antibiotics were provided continuously (metronidazole and oxacillin or ceftriaxone). A 5% glucose solution containing dipyridamole (Persantine; Istituto De Angeli/Boheringer Ingelheim, Reggello, Italy) was administered by continuous intravenous infusion (20 mg/24 hours). In addition, regular heparin (Liquemin; Roche, Indianapolis, IN, USA) was administered at a dosage of 250 microg/kg per hour or 25 IU/kg per hour (6 mg/kg per 24 hours). These heparin doses are not able to promote complete blood anticoagulation. Treatment with heparin and dipyridamole was maintained for 10 days in the first patient and for 18 days in the second. RESULTS: By 48 hours after treatment with dipyridamole and low-dose heparin, both patients recovered and presented with a good clinical condition and increased numbers of circulating platelets. Both patients were discharged in a safe clinical condition in the second month after hospital admission. CONCLUSION: Successful clinical recovery of 2 young patients with DIC with an unfavorable clinical evolution and a prognosis for a lethal outcome was achieved with the combination of a continuous infusion of dipyridamole and low doses of heparin.

Effects of clonidine and isoflurane on the myocardial contractility behavior of isolated rat hearts.

Isoflurane is chosen as an anesthesia drug for cardiac surgeries, and its effectiveness and safety have been proved in countless clinical studies. Clonidine, a central alpha-agonist, has recently been added to isoflurane to attenuate sympathetic hyperactivity by acting directly on its site of origin in the central nervous system. The ability of alpha2-adrenoceptor agonists to inhibit central sympathetic outflow may benefit patients at risk of myocardial damage by improving myocardial oxygen demand and the supply ratio and contributing to hemodynamic stability. We investigated the effects of clonidine and isoflurane, alone and in combination, on the myocardial contractility of isolated rat hearts and found that use of clonidine plus isoflurane decreased the systolic pressure somewhat, but use of the drugs separately did not exhibit this effect. Clonidine plus isoflurane did not affect +(dP/dt)max, but it did decrease -(dP/dt)max significantly compared with the use of isoflurane alone. These results indicate that clonidine and isoflurane have the capacity to interact with each other. The capacity of clonidine to decrease isoflurane's inotropic effect could theoretically contribute to improving the myocardial oxygen demand and the supply ratio, decreasing surgical stress, and benefiting patients at risk of myocardial damage.

Área valvar mitral através de medidas de meia-pressão em átrio esquerdo e capilar pulmonar / Determination of mitral valve area through pressure half-time measurements in the left atrium and pulmonary capillary wedge

OBJETIVO: Testar a validade do cálculo da área valvar mitral (AVM) aplicando o método de meia-pressão do Doppler (MP) diretamente às curvas de pressão de átrio esquerdo (AE) e capilar pulmonar (Cap). MÉTODOS: Trinta e cinco pacientes com estenose valvar mitral (EVM) foram submetidos a valvotomia mitral percutânea pela técnica de Cribier com monitorização por cálculos de AVM feitos pelos métodos tradicionais (Gorlin e Eco-Doppler) e pelo proposto. Os valores de AVM calculados antes e após os procedimentos foram comparados entre si e foi aplicado modelo de regressão linear para cálculos recíprocos de AVM. RESULTADOS: Observou-se correlação entre os valores calculados por todos os métodos. O método proposto correlacionou-se fortemente com os demais (p< 0,05) notadamente antes da abertura valvar. Foram encontradas fórmulas simples para cálculo recíproco de AVM. CONCLUSÃO: O método proposto para cálculo de AVM seja sobre a curva pressórica de AE ou Cap mostrou-se preciso e simples monitorizando com segurança os procedimentos de valvotomoa mitral percutânea.

OBJECTIVE: To confirm the validity of the calculation in MVA applying the method of Doppler pressure half-time directly in left atrial (LA) and pulmonary capillary pressure curve. METHODS: Thirty-five patients with mitral valve stenosis underwent percutaneous mitral valvotomy (PMV) using the Cribier method with MVA measurement made using the traditional methods (Gorlin and echo-Doppler) and this propose. MVA values obtained were compared and a linear regression model was used to obtain formula for reciprocal calculations of the mitral valve area. RESULTS: A statistically correlation was found between the calculated values by all methods. The proposed method showed a strong correlation (p< 0.05) with the others mainly before valve opening. Simple reciprocal calculation formulas were found for mitral valve area assessment. CONCLUSION: The proposed method for the calculation of mitral valve area using LA or Cap proved to be highly accurate and simple making it possible to safely monitor valvotomy procedures.

Determination of mitral valve area through pressure half-time measurements in the left atrium and pulmonary capillary wedge.

OBJECTIVE: To confirm the validity of the calculation in MVA applying the method of Doppler pressure half-time directly in left atrial (LA) and pulmonary capillary pressure curve. METHODS: Thirty-five patients with mitral valve stenosis underwent percutaneous mitral valvotomy (PMV) using the Cribier method with MVA measurement made using the traditional methods (Gorlin and echo-Doppler) and this propose. MVA values obtained were compared and a linear regression model was used to obtain formula for reciprocal calculations of the mitral valve area. RESULTS: A statistically correlation was found between the calculated values by all methods. The proposed method showed a strong correlation (p< 0.05) with the others mainly before valve opening. Simple reciprocal calculation formulas were found for mitral valve area assessment. CONCLUSION: The proposed method for the calculation of mitral valve area using LA or Cap proved to be highly accurate and simple making it possible to safely monitor valvotomy procedures.

Optimized technical and electrophysiological approach for treatment of atrial fibrillation.

UNLABELLED: The maze procedure initially proposed by Cox for primary atrial fibrillation treatment somehow, in its complexity, increases the morbidity risk associated with mitral valve surgery. OBJECTIVE: We sought to describe a surgical technique that considers the concepts of electrophysiology and to describe the initial results of a new surgical and electrophysiological approach that blocks the main atrial circuits as defined by Frame, and to optimize the surgical tactic for treatment of atrial fibrillation. MATERIAL AND METHODS: Eight patients with chronic atrial fibrillation and mitral valve dysfunction, with tricuspid valve regurgitation in 1 case, were operated on. The following modifications of the classic Cox procedure were employed: (1) exclusion of the left atrium appendage with an inner suture that closed the left atrial ostium, (2) exclusion of the right atrium appendage by 1 purse-string suture used for fixation of the superior vena cava draining cannula, (3) a single atrial incision, (4) transendocardium electrocauterization in the left atrium wall around all pulmonary vein ostia, and (5) substitution of the incisions and sutures in the left atrium with transendocardium electrocauterization. RESULTS: The extracorporeal circulation time varied from 64 min to 133 min (mean, 107.5 min), and the cardioplegia time varied from 40 min to 105 min. (mean, 76.7 min). All patients were in regular atrial rhythm at the end of surgery. The postoperative period was uneventful, and all patients were discharged from the hospital showing regular atrial rhythm, without definitive pacemaker implantation. In the postoperative period 6 months after surgery, 6 patients (75%) were in regular atrial rhythm with preserved atrial contractions, and 2 (25%) with atrial fibrillation, clinically controlled (New York Heart Association class II). There were no embolic complications or evidence of thrombosis in the echodopplercardiography control. CONCLUSION: It is concluded from this initial series of cases that the electrophysiolgical approach and the surgical technique employed improved the surgical treatment of atrial fibrillation, making possible the correction of mitral and tricuspid valve lesions without additional morbidity.

Effects of metoprolol and amiodarone combination on heart rate, myocardial contractility and coronary flow: Study in isolated perfused rat hearts.

BACKGROUND: Beta-blockers and amiodarone have been used concomitantly to treat arrhythmias associated with congestive heart failure. However, the combination of metoprolol and amiodarone has only been studied restrospectively, and its potential effects in congestive heart failure remain to be properly elucidated in prospective trials. OBJECTIVE: The present investigation focused on evaluating the pharmacological interaction between metoprolol and amiodarone in an isolated perfused rat heart preparation. MATERIALS AND METHODS: Adult male Wistar rats (n=24) were divided into four groups of six animals, and the effects of the metoprolol/amiodarone combination on systolic pressure, myocardial contractility (dP/dt), coronary flow (CF) and heart rate were analyzed, and the interdependent variables were compared. RESULTS: There was a negative chronotropic effect by both metoprolol and the metoprolol/amiodarone combination in isolated rat hearts. However, the acute effects of the metoprolol/amiodarone combination showed no myocardial contractility depression or bradycardia accentuation compared with metoprolol alone. CF increased by 9.2% at minute 1 through minute 5 (P=0.004) with the metoprolol/amiodarone combination. There was no difference in systolic pressure or myocardial contractility among the groups. CONCLUSIONS: The acute effects of the metoprolol/amiodarone combination in the isolated rat heart were an increase in CF, and no myocardial contractility depression or bradycardia accentuation.

Ventriculectomia parcial esquerda: operaçäo de Batista em pacientes acima de 60 anos / Partial left ventriculectomy: Batista's operation in patients older than 60 years

Fundamentos: A insuficiência cardíaca constitui-se em grave problema de saúde pública. Recente proposta de tratamento cirúrgico para a insuficiência cardíaca terminal é a ventriculectomia parcial esquerda, näo havendo publicaçöes específicas sobre seus benefícios em pacientes acima de 60 anos. Objetivo: Estudar os resultados obtidos com o tratamento da miocardiopatia dilatada em pacientes acima de 60 anos, submetidos à ventriculectomia parcial esquerda. Método: Entre maio de 1995 e dezembro de 1997 dez pacientes com idade entre 62 e 78 anos, portadores de miocardiopatia dilatada em classe funcional IV (NYHA), foram submetidos à ventriculectomia parcial esquerda no Serviço de Cirurgia Cardiotorácica da Disciplina de Cirurgia Cardiotorácica da Universidade Federal de Mato Grosso do Sul - Núcleo de Hospital Universitário. A ressecçäo, de forma elíptica, foi realizada na parede lateral do VE, entre os dois músculos papilares, estendendo-se, desde o ápice até próximo do anel mitral. Resultados: Nove (90 por cento) pacientes receberam alta hospitalar e um paciente (10 por cento) evoluiu para óbito, no sexto dia de pós-operatório. O fragmento ressecado variou de 6 a 10,5 cm de comprimento por 4 a 5,5 cm de largura, com 10,8 + ou - 1,3 cm por 5 + ou - 0,06 cm em média. O controle ecocardiográfico demonstrou: (Ver tabela). No seguimento, observou-se que três pacientes (30 por cento) encontram-se em grau funcional I ( NYHA), três pacientes (30 por cento) em II e um paciente (10 por cento) em grau funcional III. A sobrevida atuarial desses pacientes foi de 100 por cento, 87 por cento, 87 por cento e 67 por cento para 6, 12, 24 e 36 meses de seguimento, respectivamente. Conclusäo: A ventriculectomia parcial esquerda, realizada em pacientes com idade superior a 60 anos portadores de insuficiência cardíaca com severa disfunçäo hemodinâmica, apresentou mortalidade baixa, promovendo recuperaçäo acentuada do desempenho cardíaco

Influência do isoflurano na contratilidade miocárdica e fluxo coronariano de coraçöes isolados de ratos / Influence of isoflurane in myocardial contractility and coronary flow of isolated rat hearts

Foram estudados, pela técnica de Langendorff, 18 coraçoes isolados de ratos albinos adultos, submetidos a perfusao retrógrada pela soluçao de Krebs-Henseleit (pressao de 90 + 10 cm de H2O, temperatura de 36,5 + 0,5ºC). Os animais foram distribuídos nos seguintes grupos: Grupo I: controle; Grupo II: tratado com isoflurano na concentraçao de 1,5 por cento. Foram avaliados os seguintes parâmetros: freqüência cardíaca (FC), pressao sistólica (PS), pressao diastólica (PD), dp/dt e fluxo coronariano (FCo). Após 15 min de estabilizaçao, foram obtidos os valores iniciais (t0), sendo os parâmetros registrados seqüencialmente nos seguintes períodos: 1,2,4,6,10 min. Nao ocorreram variaçoes estatisticamente significantes na PS nem na dp no períoto t1 nos dois grupos estudados. Notou-se aumento da PD (p<0,05) apenas no Grupo II (4,8 mmHg no período t0, 12,8 mmHg no período t1). Ocorreram ainda diminuiçao da FC (p<0,05) e aumento do FCo (p<0,05) um minuto após a infusao da droga. Notou-se diminuiçao do FCo de forma progressiva em todos os períodos de recuperaçao (t2 a t5) após a infusao do isoflurano (p<0,05). Conclui-se que o usoflurano aumenta o fluxo coronariano durante a sua administraçao, reduzindo-o no período de recuperaçao; diminui a freqüência cardíaca e aumenta a pressao diastólica em coraçoes isolados de ratos.

Efeitos do propofol na resposta contrátil do miocárdio à dopamina e dobutamina: estudo experimental em coraçöes isolados de ratos / Effects of the propofol in the myocardial contractile response to dopamine and dobutamine: experimental study in rat's isolated heart

Objetivo: Estudo experimental das açoes farmacodinâmicas do propofol e sua interaçao com a dopamina e dobutamina em coraçoes isolados de ratos. Método: Foram estudadas as variaçoes da contratilidade miocárdica (dT/dt), em 30 coraçoes isolados de ratos. Em todos os animais, após anestesia por inalaçao de éter, os coraçoes foram excisados e perfundidos em sistema de Langendorff com soluçao de Krebs - Hensleit enriquecida com 95 por cento O2 e 5 por cento CO2, (pressao de 90 cm de H2O, temperatura constante de 37,O graus Celsius ñ O,5 graus Celsius). Foram estudados 30 animais divididos em: Grupo I (controle) - lO coraçoes perfundidos durante ll minutos com soluçao de Krebs - Hensleit; Grupo II (dopamina-propofol-dopamina) - lO coraçoes onde foram administrados dopamina (50 mcg/ml) e analisados os resultados nos 1(, 3( e 5( minutos e, posteriormente, propofol, (25 mcg/ml) infundindo-se l minuto após, dopamina (50 mcg/ml) e analisando-se os 1(, 3( e 5( minutos, Grupo III (dobutamina-propofoldobutamina) - diferiu do Grupo II pela substituiçao da dopamina por dobutamina (50 mcg/ml). Resultados: No Grupo I observou-se que a dT/dt variou de 39,57 ñ 3,97 (g.seg -l) a 39,37 ñ 3,44 (g.seg -1) (p>0,05) no período estudado. No Grupo II observou-se que, após a administraçao de propofol e dopamina, a dT/dt em (g.seg -l) apresentou queda de 17,61 por cento (pO,O5) no 1( minuto; 3,62 por cento (p>O,O5) no 3( minuto e 3,08 por cento (p>O,O5) no 5( minuto, comparado à injeçao isolada da dobutamina. Conclusao: O propofol (25 mcg/ml) nao alterou a resposta contrátil do miocárdio à dobutamina (50 mcg/ ml); no entanto, inibiu a resposta esperada pela açao da dopamina (50 mcg/ml) na contratilidade miocárdica.

Cardioplegia retrógrada seqüencial / Sequencial retrograde cardioplegy

Estudou-se o padrao de distribuiçao miocárdica de soluçao cardioplégica (SC) cristalóide gelada (3 graus Celsius - 4 graus Celsius) perfundida nos coraçoes de 15 caes mestiços com pesos variáveis entre 10-15 kg. Após anestesia e toracotomia mediana anterior, o pericárdio foi aberto, sendo estabelecida circulaçao extracorpórea. As seguintes vias foram empregadas para injeçao cardioplégica: 1) Anterógrada - por canulaçao da aorta ascendente a montante da pinça de oclusao; 2) Retrógrada Seletiva - através de cânula com balao auto-inflável introduzido no seio coronário (SCo); 3) Retrógrada Total - através de cânula introduzida no átrio direito (AD); 4) Retrógrada Seqüencial SCo-AD - com a SC injetada primeiro pelo seio coronário até a temperatura do septo interventricular atingir l6 graus Celsius e, em seqüência, pela cânula no átrio direito como na técnica retrógrada total, com o tronco arterial pulmonar ocluído; 5)Retrógrada Seqüencial SCo-VD - com a cavidade do ventrículo direito perfundida por cânula passada através da valva tricúspide. Controlou-se a variaçao da temperatura miocárdica no ventrículo esquerdo, VD, AD e regiao do no sinoatrial, por meio de teletermômetro Omega com termistor de agulha. Pode-se constatar que o esfriamento cardíaco uniforme, o menor volume e o menor tempo de injeçao ocorreram com a técnica anterógrada, seguida em excelência pelas técnicas retrógradas seqüenciais SCo-AD e SCo-VD. Concluiu-se que a técnica de cardioplegia retrógrada seqüencial é significantemente melhor que as retrógradas seletivas pelo SCo e total pelo AD, como usualmente empregadas para proteçao miocárdica, quando comparadas com a técnica de perfusao anterógrada pela aorta.

Análise espectral do pulso arterial durante a circulaçäo extracorpórea: estudo experimental em cäes / Spectral analysis of the arterial pulse during cardiopulmonary bypass: experimental study in dogs

Objetivo: Avaliar o modelo do pulso arterial através da análise espectral que melhor reproduza as condições circulatórias fisiológicas durante a circulação extracorpórea com fluxo pulsátil e laminar. Material e Métodos: Dez cães adultos submetidos à circulação extracorpórea com bomba de roletes e de fluxo pulsátil instaladas em paralelo. O fluxo da circulação extracorpórea foi ajustado ao pré-existente que foi medido com fluxômetro Statham 2200. As curvas de pressão tanto com bomba de fluxo laminar, quanto com bomba de fluxo pulsátil foram registradas em fita magnética HP Recorder e analisados pelo método Fast Fourier Transform (algoritmo CooleyTukeyl. Variou-se o período da bomba pulsátil em relação ao ciclo total de 70, 60, 50, 40 e 30%. Resultados: O traçado do pulso arterial durante o uso da bomba de roletes mostrou um onda bífida com depressão profunda seguida por outra de pico único. Foram observados, espectralmente, três componentes de mesma amplitude. O uso de bomba pulsátil proporcionou, à análise espectral, componentes harmônicos de amplitudes inversamente proporcionais à relação ejeção/ciclo...

Purpose: Spectral analysis of arterial pulse was performed during cardiopulmonary bypass with both pulsatile and continuous flow in order to evaluate the pulse model best suitable to reproduce physiological circulatory conditions. Material and Methods: Ten adult mongrel dogs were submitted to cardiopulmonary bypass with a roller pump for continuous flow and pulsatile flow pump in paralel. The physiological pressure waves, the roller pump waves and the pulsatile pump flow waves were recorded. During the pulsatil flow we varied the ejective period of the pump in relation to the total cycle by 70%, 60%, 50%, 40% and 30%. Results: The roller pump flow showed a bifid wave followed by single peak wave. During spectral analysis we observed three harmonic components of the same amplitude. The using of the pulsatile pump flow proportionated, by spectral analysis, harmonic components whose amplitudes are inversely proportional for ejection/cycle ratio...

Analise critica do tempo de coagulacao ativada durante circulacao extracorporea experimental com discrasia sanguinea. / The severe analysis of activated time of coagulation during experimental extracorporeal circulation with blood dyscrasia

Coagulacao intravascular disseminada (CIVD) foi intencionalmente induzia en dez caes, submetidos a circulacao extracorporea com heparinizacao previa de apenas 0,5 mg/kg de peso corporeo. Determinacoes dos tempos de coagulacao ativada (TCA), protrombina, trombina, tromboplastina parcial ativada, e de recalcificacao do plasma, bem como das concentracoes de fibrinogenio foram realizadas nos seguintes periodos; antes e apos heparinizacao e aos 30, 60, 90 e 120 minutos de perfuracao.Os resultados demonstram que o TCA foi o unico teste a nao sofrer modificacao significante compativel com o diagnostico de grave coagulopatia existente

Parada cardiaca anoxica - tres horas de protecao - nova solucao cardioplegica. / Anoxic cardiac arrest - 3 hours of protection - new cardioplegic solution

O efeito de nova solucao cardioplegica foi estudado experimentalmente em caes, submetidos a toracotomia e circulacao extracorporea.Foram controladas as variacoes pressoricas em ventriculo esquerdo, modificacao da forca e do deslocamento miocardio bem como estudada a dinamica do ventriculo esquerdo por cineangiocardiografia. A solucao cardioplegica foi infundida em volumes correspondentes a 6 ml/ kg, repetido a intervalos de 40 minutos de anoxia. Os resultados obtidos demonstram protecao miocardica eficaz com normalizacao dos parametros controlados apos o reinicio da circulacao coronaria normal

Correlacao entre calcio e quetamina nas variacoes do estado contratil do miocardio. / Correlations between calcium and ketamine in the variations of contractile state of myocardium

A correlacao entre as concentracoes de calcio serico e de quetamina nas variacoes do estado contratil do miocardio foi investigada experimentalmente. Empregou-se preparacao coracao-pulmao isolada, de caes com tecnica que permitiu avalicao da dinamica ventricular esquerda; tendo-se registrado as modificacoes pressoricas intraventriculares, a forca de contracao e o debito cardiaco. Constatou-se depressao miocardica acentuada induzida pela quetamina, administrada diretamente no atrio direito, em dose correspondente a 15 mg/kg de peso corporeo, enquanto a concentracao serica de calcio mantinha-se entre 6,5 e 11,0 mg%. A administracao de 0,5 g de gluconato de calcio possibilitou completa recuperacao funcional cardiaca. Pode-se tambem constatar que mediante concentracoes sericas de calcio superiores a 15 mg%, todos os coracoes suportavam indenes, doses de quetamina superiores a 20 mg/kg de peso corporeo