Evaluation of pulmonary arterial pressure in acute pulmonary embolism.

Twenty-six patients with acute pulmonary embolism underwent hemodynamic examination. Twenty-three of the patients were free of prior cardiopulmonary diseases. The other 3 patients had prior history of cardiac disease. In the 23 patients, the mean pulmonary arterial pressure (PAm) ranged from normal range to 35 mmHg at the time of the embolic event and generally declined within ten days after the embolic event. However, in the 3 patients with a history of disease, reelevation of PAm was observed during the pressure monitoring. PAm was positively correlated with the extent of pulmonary vascular obstruction (r = 0.863, p < 0.01) and also with mean right atrial pressure (RAm, r = 0.830, p < 0.01). In the presence of prior cardiac disease, PAm in patients with normal preembolic PAm increased proportionally to the extent of obstruction. Continuous hemodynamic monitoring is valuable for estimating the degree of embolic obstruction and the speed of embolus resolution and for detecting new embolic episodes in some cases.