We have studied the effect of changes in pulse wave reflection on the configurations of pressure and flow in systemic and pulmonary circulation. Electromagnetic flow transducers, atrial catheters, and pacing leads were implanted in 10 dogs. In four animals, the flow transducer was placed on the pulmonary artery, in another four on the ascending aorta, and in two additional dogs on both vessels....

The pulmonary circulation is a highly specialized vascular bed that physically and functionally connects the heart and the lungs. The interdependence of these two organs is illustrated in embryonic development, when the lung endoderm protrudes into the surrounding mesoderm as the heart tube elongates and folds into structurally distinct chambers. The pulmonary vascular precursors then undergo h...

OBJECTIVE To study the short-term effects of inhaled nitric oxide in infants and young children with congenital heart disease. SETTING A supraregional referral centre for children with congenital heart disease. PATIENTS AND METHODS 22 infants and children aged 3-32 months (median age 5 months) with congenital heart disease undergoing preoperative cardiac catheterisation. All but one infant ...

T WO MAJOR obstacles complicate the study of the pulmonary circulation in man: the inaccessibility of the pulmonary vessels for direct cannulation, and the multiplicity of extravascular factors that influence pressure-flow-volume relationships within the lungs. New technics have largely circumvented the first difficulty; the second difficulty is minimal in the normal resting subject, but is exa...

Calcium channel blockade provides a logical approach to the treatment of pulmonary hypertension because these drugs exert direct vasodilator effects in the highly constricted pulmonary circulation. To determine the effectiveness of verapamil in the treatment of primary pulmonary hypertension the haemodynamic effects of the drug were evaluated in seven patients with this disorder; 10 mg was give...

IN THE 2 companion papers, we have considered some effects of acute hypoxia on the pulmonary circulation. The present study, concerned with the effects of acute hypercapnia on the pulmonary eirculation, was prompted by 2 prospects: (1) that an acute increase in alveolar and arterial P 0, brought about by the inhalation of air enriched with carbon dioxide, might simulate the effects on the pulmo...

5. Heath D, Edwards JE: The pathology of hypertensive pulmonary vascular disease: a description of six grades of structural changes in the -pulmonary arteries with special reference to congenital cardiac septal defects. Circulation 18: 533, 1958 6. Mair DD, Ritter DG, Davis GD, Wallace RB, Danielson GK, McGoon DC: Selection of patients with truncus arteriosus for surgical correction: anatomic a...

We have studied the effect of changes in pulse wave reflection on the configurations of pressure and flow in systemic and pulmonary circulation. Electromagnetic flow transducers, atrial catheters, and pacing leads were implanted in 10 dogs. In four animals, the flow transducer was placed on the pulmonary artery, in another four on the ascending aorta, and in two additional dogs on both vessels....

Exercise is an important determinant of health but is significantly reduced in the patient with a univentricular circulation. Normal exercise physiology mandates an increase in pulmonary artery pressures which places an increased work demand on the right ventricle (RV). In a biventricular circulation with pathological increases in pulmonary vascular resistance and/or reductions in RV function, ...