Avaliação dos fluxos das valvas aórtica e pulmonar com ecocardiografia Doppler pulsátil em cães clinicamente sadios

Avaliaram-se com Doppler pulsátil os fluxos das valvas aórtica (AO) e pulmonar (Pul) por meio de análise qualitativa (presença de regurgitações valvares e características do espectro avaliado) e quantitativa, com obtenção de parâmetros ecocardiográficos como velocidades máxima (V. Max.) e média (V. Me.), integral de velocidade (VTI), tempo de aceleração (TA) e ejeção (TE), de 30 cães considerados clinicamente sadios por meio de exames físico, laboratoriais, eletrocardiográfico, ecocardiográfico (modos uni e bidimensional), radiográfico de tórax e mensuração da pressão arterial sistêmica. Obtiveram-se os seguintes resultados para os referidos parâmetros: V.max. AO= 1,22± 19,38m/s; V. Me. AO= 0,72± 0,08m/s; VTI AO= 0,14± 0,02m; TA AO= 38,80± 11,29ms; TE AO= 197,90± 24,77ms; V. Max. Pul= 0,95± 0,18m/s; V. Me. Pul= 0,63± 0,10m/s; VTI Pul= 0,13± 0,02m; TA Pul= 70,97± 18,87ms; TE Pul= 203,70± 28,98ms. Em apenas três animais observou-se regurgitação pulmonar. Alguns parâmetros apresentaram correlação negativa com a variável freqüência cardíaca (VTI AO, TE AO, VTI Pul, TA Pul, TE Pul); outros correlação positiva com a variável peso (VTI AO, TA AO, TE AO, VTI Pul, TE Pul,) e não se observou influência da variável sexo na maioria dos parâmetros avaliados. Na comparação entre os dois fluxos, observaram-se V. Max. AO e V. Me. AO maiores que V. Max. Pul. e V. Me. Pul., respectivamente, VTI AO maior que VTI Pul, e TA AO menor que TA Pul.

Outflow occlusion for circulatory arrest in dogs

The purpose of this study was to evaluate the possibility of producing circulatory arrest by occlusion of the pulmonary trunk as an alternative to the venous inflow occlusion through the left hemithorax. Eight healthy mongrel dogs were divided in two groups. Group I underwent 4 minutes of outflow occlusion and Group II was submitted to 8 minutes of circulatory arrest. Outflow occlusion was performed through left thoracotomy and pericardiotomy by passing a Rumel tourniquet around the pulmonary trunk. Physical examination, electrocardiography, echocardiography, blood gas analyses, hemodynamic, and oxygen transport variables were obtained before and after the procedure. The dogs from Group I did not have any clinical, electrocardiographic, echocardiographic, or hemo-dynamic abnormalities after anesthetic recover. In the Group II, only one dog survived, which had no clinical, electrocardiographic, or echocardiographic abnormalities. In this last dog, just after releasing the occlusion, it was detected increases in the following parameters: heart rate (HR), systolic, diastolic and mean arterial blood pressure (SAP; DAP; MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), central venous pressure (CVP), cardiac output (CO), systolic index (SI), cardiac index (CI), left and right ventricular stroke work (LVSW; RVSW), oxygen delivery index (DO2), oxygen consumption index (VO2), and oxygen extraction (O2 ext). Moreover, the oxygen content of arterial and mixed venous blood (CaO2; CvO2), and the arterial and mixed venous partial pressure of oxygen (PaO2; PvO2) were decreased 5 minutes after circulatory arrest. Outflow occlusion is a feasible surgical procedure for period of 4 minutes of circulatory arrest.

Echocardiographic study of paediatric patients with mucopolysaccharidosis

Principle Mucopolysaccharidosis is an inborn error of metabolism causing glucosaminoglycans tissue storage. Cardiovascular involvement is variable but contributes significantly towards the morbidity and mortality of the patients. Objective To characterise the echocardiographic abnormalities in children and adolescents with different types of mucopolysaccharidosis. Method Echocardiograms and medical records of 28 patients aged 2–14 years, seen from 2003 to 2005, were revised. At that time, the enzymatic replacement therapy was still not available in our institution.Results Echocardiographic alterations were detected in 26 patients (93 per cent), whereas 16 (57 per cent) had abnormal auscultation, and only 6 (21 per cent) presented with cardiovascular complaint. Mitral valve thickening with dysfunction (regurgitation, stenosis, or double lesion) was diagnosed in 60.8 per cent, left ventricular hypertrophy in 43 per cent and aortic valve thickening with regurgitation in 35.8 per cent of the patients. There was no systolic dysfunction and mild left diastolic dysfunction was shown in 21.5 per cent of the patients. Pulmonary hypertension was present in 36 per cent of the patients, causing the only two deaths recorded. There was a strong association between the accumulation of dermatan sulphate and the presence of mitral valve dysfunction (p = 0.0003), aortic valve dysfunction (p = 0.006), and pulmonary hypertension (p = 0.006). Among individuals with two or more examinations, 82 per cent had a worsening evolution. Conclusions Echocardiographic alterations in children with Mucopolysaccharidosis are frequent and have a progressive character Left valve lesions, ventricular hypertrophy, and pulmonary hypertension were the most common findings and there was an association between the accumulation of dermatan sulphate and cardiovascular involvement. Unlike in adults, pulmonary hypertension was the main cause of death, not left ventricle systolic dysfunction