1/104. Competitive pulmonary flow in infancy: the effect of respiration.Superior caval flow during positive pressure mechanical ventilation and spontaneous breathing was investigated by Doppler echocardiography in a neonate with a coexisting superior cavopulmonary shunt and an aortopulmonary shunt. During positive pressure ventilation, retrograde systolic flow in the superior vena cava was recorded, with low velocity anterograde flow. This pattern was reversed during spontaneous respiration. Low intrathoracic pressure plays an important role in maintaining anterograde pulmonary blood flow in patients with this physiology.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
2/104. Computational fluid dynamic and magnetic resonance analyses of flow distribution between the lungs after total cavopulmonary connection.Total cavopulmonary connection is a surgical procedure adopted to treat complex congenital malformations of the right heart. It consists basically in a connection of both venae cavae directly to the right pulmonary artery. In this paper a three-dimensional model of this connection is presented, which is based on in vivo measurements performed by means of magnetic resonance. The model was developed by means of computational fluid dynamics techniques, namely the finite element method. The aim of this study was to verify the capability of such a model to predict the distribution of the blood flow into the pulmonary arteries, by comparison with in vivo velocity measurements. Different simulations were performed on a single clinical case to test the sensitivity of the model to different boundary conditions, in terms of inlet velocity profiles as well as outlet pressure levels. Results showed that the flow distribution between the lungs is slightly affected by the shape of inlet velocity profiles, whereas it is influenced by different pressure levels to a greater extent.- - - - - - - - - - ranking = 0.66666666666667keywords = pressure (Clic here for more details about this article) |
3/104. Paired ventricular pacing: an alternative therapy for postoperative junctional ectopic tachycardia in congenital heart disease.Junctional ectopic tachycardia (JET) is one of the most life-threatening postoperative arrhythmias in children with congenital heart disease, and medical management is difficult. Paired ventricular pacing (PVP) may provide a safe alternative mode of management. We evaluated the safety and efficacy of PVP for the management of postoperative JET in patients with congenital heart disease. A retrospective collection of data was done from 1981-1995. PVP was successfully tried in five postoperative patients (age range: 37 days to 22 years, median: 10 months). Onset of JET was 3-60 hours (mean /- SD, 19 /- 23 hours) postoperatively. The maximal JET rate was 261 /- 39 beats/min. PVP was used as the first line of management in three patients and was successful in all patients. It resulted in an instantaneous increase in blood pressure from 66 /- 9 to 94 /- 15 mmHg (42% increase) and was required for 12 /- 14 hours (range 2-36 hours). No complications were noted. Therefore, in our experience, this is a safe alternative modality for the control of postoperative JET.- - - - - - - - - - ranking = 0.33333333333333keywords = pressure (Clic here for more details about this article) |
4/104. Circumscribed intestinal protein loss with deficiency in CD4 lymphocytes after the fontan procedure.Protein-losing enteropathy is an important complication after right heart bypass operations (fontan procedure). Laboratory examinations usually reveal hypoalbuminaemia, hypoproteinaemia, elevated alpha(1)-antitrypsin clearance, and lymphocytopenia. A case of protein-losing enteropathy after fontan procedure is reported with a circumscribed protein loss in the region of the terminal ileum despite good haemodynamics. The patient developed only mild hypoalbuminaemia and no diarrhoea but severe cellular and humoral immune abnormalities, namely a markedly decreased proportion of CD4 lymphocytes but normal proportion of CD8 lymphocytes (CD4 14%, CD8 23%) and decreased serum levels of immunoglobulin g. Intestinal biopsies revealed normal mucosa. This report is unique as it is the first to describe a ratio of CD4 to CD8 lymphocytes <1 due to an almost selective loss of CD4 lymphocytes and a circumscribed intestinal protein loss in a patient who developed protein-losing enteropathy after Fontan operation. CONCLUSION: There is a severe decrease of CD4 lymphocytes of unknown origin in a patient with circumscribed intestinal protein loss after Fontan operation. Passive leakage of lymph fluid due to abnormal systemic venous pressure is not a sufficient explanation of the almost selective loss of CD4 lymphocytes. Primary or secondary activation of the immune system may influence structural integrity and permeability of the intestinal wall and may play a triggering role in protein-losing enteropathy after the fontan procedure.- - - - - - - - - - ranking = 0.33333333333333keywords = pressure (Clic here for more details about this article) |
5/104. Early therapeutic experience with the endothelin antagonist BQ-123 in pulmonary hypertension after congenital heart surgery.OBJECTIVE: To assess the effect of endothelin type A (ET(A)) receptor antagonism in infants with pulmonary hypertension following corrective surgery for congenital heart disease. DESIGN: Open label, preliminary study. SETTING: Tertiary paediatric cardiothoracic surgical centre. patients: Three infants (aged 3 weeks, 7 weeks, and 8 months) with postoperative pulmonary hypertension unresponsive to conventional treatment, including inhaled nitric oxide. INTERVENTIONS: patients received incremental intravenous infusions (0.1 to 0.3 mg/kg/h) of the ET(A) receptor antagonist BQ-123. MAIN OUTCOME MEASURES: The response to BQ-123 administration was determined using continuous invasive monitoring of cardiorespiratory variables. RESULTS: BQ-123 infusion caused a reduction in the ratio of pulmonary to systemic pressures (0.62 (0.01) to 0.52 (0.03), mean (SEM)) with an accompanying decrease in right ventricular stroke work index (4.6 (0.4) to 2.5 (0.3) g/m) and a tendency for the cardiac index to rise (2.1 (0.2) to 2.7 (0.6) l/min/kg/m(2)). This was associated with a well tolerated fall in the arterial partial pressure of oxygen (16.5 (4.1) to 12.4 (3.3) kPa) and mean systemic arterial pressure (57 (3) to 39 (3) mm Hg). CONCLUSIONS: ET(A) receptor antagonism in infants with postoperative pulmonary hypertension after corrective surgery for congenital heart disease led to significant improvement in pulmonary haemodynamic indices. However, these benefits were associated with reductions in systemic blood pressure and arterial oxygen saturation, the latter consistent with a ventilation-perfusion mismatch. On the basis of these results, studies in pulmonary hypertension will need to proceed with caution.- - - - - - - - - - ranking = 1.3333333333333keywords = pressure (Clic here for more details about this article) |
6/104. Bronchial casts in children with cardiopathies: the role of pulmonary lymphatic abnormalities.Expectoration of bronchial casts, a condition also called plastic bronchitis, is very rare in children. Bronchial casts may be associated with bronchopulmonary diseases associated with mucus hypersecretion, bronchopulmonary bacterial infections, congenital and acquired cardiopathies, or pulmonary lymphatic abnormalities. A classification based on anatomy and pathology has been proposed which identifies an "acellular" group associated with congenital cardiopathies and palliative surgery. We report on 3 cases with bronchial casts associated with cardiopathy. Observations suggest that the formation of bronchial casts may result from lymphatic leakage into the bronchi. The 3 cases on which we report were immunodeficient and had pulmonary lymphatic abnormalities. The bronchial casts contained lymphocytes and lipids, as determined by histologic examination. In the absence of congenital pulmonary or diffuse lymphatic dysplasia associated with cardiopathy, the principal factors resulting in the formation of bronchial casts appear to be surgical trauma to the lymphatic channels surrounding the bronchi, pleural adhesions, and high systemic venous blood pressure. The prognosis for these patients is poor, and possibilities for treatment are limited.- - - - - - - - - - ranking = 0.33333333333333keywords = pressure (Clic here for more details about this article) |
7/104. Left superior vena cava connection to unroofed coronary sinus associated with positional cyanosis: successful transcatheter treatment using Gianturco-Grifka vascular occlusion device.A persistent left superior vena cava connection to an unroofed coronary sinus is a rare cardiac anomaly that is associated with a variable degree of cyanosis. We report an infant with this condition and the unusual feature of cyanosis dependent on head position. When the patient's head was rotated to the left, he developed severe stenosis of the left internal jugular vein, enlarged cervical collateral veins that connected to the right superior vena cava and had an oxygen saturation 95%. When the patient's head was rotated to the right, the left internal jugular vein was widely patent and systemic oxygen saturation decreased to 87%. There was no right ventricular volume overload. Temporary occlusion of the left superior vena cava documented tolerable proximal venous pressure. cyanosis was relieved by transcatheter closure of the left superior vena cava with a Gianturco-Grifka vascular occlusion device. Cathet. Cardiovasc. Intervent. 48:369-373, 1999.- - - - - - - - - - ranking = 0.33333333333333keywords = pressure (Clic here for more details about this article) |
8/104. Doppler echocardiographic evaluation of the hemodynamics in absent aortic valve.hemodynamics were estimated by Doppler echocardiography in a neonate with an absent aortic valve and absent or extremely hypoplastic mitral valve. The coronary blood flow depended on the increased end-diastolic pressure of the left ventricle. Pulmonary venous congestion, which was also due to the increased end-diastolic pressure of the left ventricle, may induce decreased oxygen saturation and, subsequently, further myocardial hypoxia, poor contraction and increased end-diastolic pressure of the left ventricle. Finally, hypoxic blood was supplied to each organ from the pulmonary artery through the ductus arteriosus, which induced severe acidosis and differential cyanosis after birth.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
9/104. Pulmonary vein atresia with Shone's anomaly in an infant: a case report.We report a case of individual pulmonary vein atresia associated with multiple levels of left heart obstruction, including aortic coarctation, valvular aortic stenosis, and parachute mitral valves with stenosis. The diagnosis of pulmonary vein obstruction is likely to be missed in patients who also have other left heart obstructive diseases, since the latter usually dominates the clinical presentation. We diagnosed the existence of individual pulmonary vein atresia preoperatively via cardiac catheterization. The pulmonary artery angiograms revealed back and forth motion of the dye with no visualization of either a capillary or venous phase on the lesion side. The pulmonary capillary wedge pressure was unevenly elevated and highest on the lesion side. The results were later confirmed by operation and autopsy. Thus, selective pulmonary artery catheterization and angiography remains a good diagnostic tool to rule out the existence of pulmonary vein obstruction in cases which have multiple levels of left heart obstruction.- - - - - - - - - - ranking = 0.33333333333333keywords = pressure (Clic here for more details about this article) |
10/104. Bilateral diaphragmatic paralysis after cardiac surgery: ventilatory assistance by nasal mask continuous positive airway pressure.The case of an 8-month-old boy with bilateral diaphragmatic paralysis after surgical reoperation for congenital heart disease is presented. In order to avoid repeated intubation and long-term mechanical ventilation or tracheotomy, we used nasal mask continuous positive airway pressure (CPAP) as an alternative method for assisted ventilation. Within 24 hours the boy accepted the nasal mask and symptoms such as dyspnea and sweating disappeared. Respiratory movements became regular and oxygen saturation increased. Nasal mask CPAP may serve as an alternative treatment of bilateral diaphragmatic paralysis in infants, thereby avoiding tracheotomy or long-term mechanical ventilation.- - - - - - - - - - ranking = 1.6666666666667keywords = pressure (Clic here for more details about this article) |
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