denopamine and Hypertension--Pulmonary

The purpose of this study is to evaluate hemodynamic effects and clinical benefit of oral denopamine in infants with left to right shunt disease. We measured heart rates, left ventricular end-diastolic and end-systolic dimensions, shortening fractions, peak and mean flow velocities of the main pulmonary artery and ascending aorta at 30, 60 and 90 min after oral denopamine using Doppler echocardiography. Seventeen infants with ventricular septal defect and pulmonary hypertension (mean pulmonary artery pressures higher than 25 mmHg) were divided into two groups depending upon the doses of denopamine; group 1 received 1 mg/kg, and group 2 was given 0.5 mg/kg. Serum concentrations of denopamine were measured with high performance liquid chromatography after completion of these evaluations. In both groups, heart rates and left ventricular shortening fractions increased, and left ventricular end-systolic dimensions decreased significantly. Although peak and mean velocities of aortic and pulmonary flows increased significantly, there were no significant alterations in peak and mean velocity ratios of pulmonary to aortic flow. There was no significant difference in the serum concentration of denopamine between the two groups. However, percentage changes of some indices, such as heart rates, left ventricular end-systolic dimensions, peak aortic and pulmonary flow velocities, and mean aortic flow velocities exponentially correlated to serum concentrations of denopamine. In conclusion, denopamine is supposed to have beneficial actions to augment the systemic output by enhancing the left ventricular pump function in patients of ventricular septal defect. However, we should be careful for denopamine not to produce excessive increases in heart rate and pulmonary blood flow.

Topics: Administration, Oral; Blood Flow Velocity; Cardiotonic Agents; Echocardiography, Doppler; Ethanolamines; Heart Septal Defects, Ventricular; Hemodynamics; Humans; Hypertension, Pulmonary; Infant; Ventricular Function, Left

The acute hemodynamic and blood gas changes caused by denopamine (2 micrograms/kg/min, d.i.) were investigated in 13 patients with chronic respiratory failure and secondary pulmonary hypertension. Denopamine significantly reduced mean pulmonary arterial pressure from 25 +/- 7 to 23 +/- 7 mmHg (p less than 0.05), and pulmonary vascular resistance from 314 +/- 166 to 276 +/- 168 dyne/sec/cm-5 (p less than 0.05), while mean systemic arterial pressure and systemic vascular resistance showed no significant change. Pulmonary-systemic vascular resistance ratio was reduced significantly from 0.22 +/- 0.09 to 0.18 +/- 0.09 (p less than 0.05). These findings suggest that denopamine has more marked effects on the pulmonary artery than on systemic arteries. Arterial oxygen tension (PaO2) increased significantly from 59.0 +/- 8.1 to 62.5 +/- 10.5 Torr (p less than 0.01), and arterial carbon dioxide tension (PaCO2) decreased significantly from 49.1 +/- 6.8 to 44.6 +/- 7.0 Torr (p less than 0.01) by denopamine. Mixed venous oxygen tension (PvO2), which is an indicator of tissue oxygenation, increased significantly from 33.3 +/- 3.5 to 34.4 +/- 3.3 Torr (p less than 0.05). We conclude that denopamine is thought to be useful for the improvement of hemodynamics and tissue oxygenation in patients with secondary pulmonary hypertension. However, further long-term studies are necessary to establish its therapeutic efficacy.

Topics: Adult; Aged; Carbon Dioxide; Ethanolamines; Female; Hemodynamics; Humans; Hypertension, Pulmonary; Male; Middle Aged; Oxygen; Oxygen Consumption; Partial Pressure; Pulmonary Circulation; Respiratory Insufficiency

We report a 52-years-old female patient with collagen disease and pulmonary hypertension. Denopamine, beta-adrenergic agonist, decreased her high pulmonary arterial pressure and improved dyspnea on exercise after long term use. She had suffered from Raynaud's phenomenon, pulmonary fibrosis, shortening of lingual frenulum and positive ANA and RA test. Although her pulmonary fibrosis had been well controlled by azathioprine, dyspnea on exercise became worse, so she admitted to our hospital for further examination in Feb 1988. Right heart catheterization revealed her high pulmonary arterial pressure (mean 29 mmHg). Under right heart catheterization, denopamine markedly decreased her pulmonary arterial pressure and increased her cardiac output. After about 6 weeks' use of denopamine, her mean pulmonary arterial pressure decreased to 15 mmHg, PO2 increased from 43 to 62 mmHg and dyspnea improved. Denopamine has been regarded as a selective beta 1-adrenergic agonist. In this case, denopamine might have beta 2-agonist effect to dilate pulmonary vasculature, or have secondary effect to increase PO2 by the improvement of cardiac function. Denopamine might be useful for pulmonary hypertension with collagen diseases.

Topics: Adrenergic beta-Agonists; Collagen Diseases; Ethanolamines; Female; Humans; Hypertension, Pulmonary; Middle Aged; Pulmonary Wedge Pressure