Abstract
The acute effects of intravenous lanatoside C on cardiopulmonary dynamics were studied in 11 patients with mitral valve disease and 3 patients with chronic pulmonary diseases. All patients were not in cardiac failure, and control data revealed that pulmonary hypertension of mild to severe degrees was present in 11 patients.
In studying parameters of cardiopulmonary dynamics including the left side of the heart, before and after administration of the drug, the following results were obtained.
1. Mean pulmonary artery pressure decreased in 5 cases, and cardiac output rose in 3 and fell in 2.
2. The cardiodynamic responses were distinguished by 3 patterns. In the first pattern, a complete absence of hemodynamic changes except for diminished pulse rate was noted. The second pattern demonstrated a reduction in left atrial pressure accompanied by a reduction in pulmonary artery pressure. The third pattern was characterized by a reduction in left atrial pressure with little or no change in pulmonary artery pressure.
3. All patients with normal hemodynamics showed the first pattern. The second pattern was observed in patients with unobstructed outflow from the pulmonary artery to the left atrium, while the third pattern was observed only in patients who had obstruction to the passage of blood into the pulmonary vascular system.
4. Pulmonary blood volume was unchanged irrespective of changes in cardiac output or in pressures in the lesser circulation.
5. On the basis of the data obtained, mode of action in reducing pulmonary hypertension and its clinical significance were related.
