Three-compartment elastance modeling predicts that the magnitude of gain is solely dependent on the ratio of free wall and septal elastances. However, when nonlinearities in pressure-volume relationships are considered, the same model predicts that gain is load dependent. We therefore studied left-to-right ventricular interactions in the isolated cross-perfused canine heart preparation to deter...

P investigations of the hemodynamic effects of progressive constriction of the pulmonary artery have demonstrated the basic principles of right ventricular compensation for an increase in resistance to outflow." Acute obstruction of the pulmonary artery results initially in an increase in right ventricular diastolic volume and in increased vigor of cardiac contraction, with maintenance of cardi...

The relationship between coronary perfusion pressure and regional myocardial performance of the right ventricular free wall was studied, in the presence or absence of right ventricular hypertension in 13 open-chest dogs. The right coronary artery was perfused through a shunt from a carotid artery. Regional systolic shortening of the right ventricular free wall was measured by means of a sonomic...

It has been stated that the electrocardiogram in pulmonary valve stenosis gives an accurate estimate of right ventricular systolic pressure. Nadas (1957) writes "we have not found any patient with a right ventricular systolic pressure of more than 100 mm. of Hg who has not demonstrated at least one of the following three important electrocardiographic criteria: (1) RVY of more than 20 mms., (2)...

Background Left ventricular (LV) and right ventricular (RV) systolic performance, typically measured as the ejection fraction (EF), is strongly correlated with mortality. However, CMR provides multiple measures that may also reflect systolic performance including LV volumes and cardiac outflow. We examined the predictive relationship of multiple potential measures of cardiac systolic performanc...

OBJECTIVE To assess prognosis of pulmonary thromboembolism using tissue Doppler echocardiography and brain natriuretic peptide. METHODS Patients aged over 18 years were evaluated within 24 hours of confirmed diagnosis (chest tomography/pulmonary scintigraphy) of pulmonary embolism using two-dimensional echocardiography and tissue Doppler for right ventricular systolic (s') velocities, strain,...

To show that right ventricular wall thickness (RVWT) measurements can be made with precision by echocardiography, we correlated these measurements with those obtained at necropsy in 32 terminal patients. The correlation between the echocardiographic diastolic right ventricular wall thickness (mean 4.0 +/- 1.62 mm) and the necropsy measurement (mean 4.3 +/- 1.52 mm) was good (r = 0.83) in all 32...

background: heart disease is the main cause of mortality and morbidity in patients with beta thalassemia, rendering its early diagnosis vital. we studied and compared echocardiographic findings in patients with beta thalassemia major, patients with beta thalassemia intermedia, and a control group. methods: eighty asymptomatic patients with thalassemia major and 22 asymptomatic cases with thalas...

background: we sought to assess right ventricular (rv) systolic and diastolic functions via tissue doppler imaging (tdi) in order to discriminate right-to-left (bidirectional) from left-to-right intracardiac shunts. methods: a tissue doppler velocity study via doppler echocardiography was performed in 20 patients with left-to-right shunt (without evidence of significant pulmonary hypertension) ...