The Journal of Thoracic and Cardiovascular Surgery, Vol 96, 39-43, Copyright © 1988 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Pulmonary vascular dynamics after percutaneous mitral valvotomy
PC Block and IF Palacios
Department of Medicine, Massachusetts General Hospital, Boston 02114.
Hemodynamic studies were performed immediately before, within 1/2 hour, and
every 8 hours for 24 hours after percutaneous mitral valvotomy in 22
patients with severe mitral stenosis and pulmonary hypertension. The mean
pressure in the left atrium decreased from 27 +/- 2 mm Hg to 14 +/- 1 mm Hg
(p less than 0.01) immediately after successful valvotomy. There was no
significant further drop in left atrial pressure (or pulmonary capillary
wedge pressure) over 24 hours. Mean cardiac output increased from 3.9 +/-
0.3 L/min to 4.6 +/- 0.3 L/min immediately after successful valvotomy (p
less than 0.01). Cardiac output continued to rise for the next 8 hours and
plateaued during the 24-hour period of observation. Pulmonary vascular
resistance dropped immediately after the relief of mitral valve obstruction
in all patients. In the group of patients who had elevated pulmonary
vascular resistance after valvotomy, resistance continued to drop
significantly (p less than 0.05) over the next 24 hours. In some cases it
did not fall to normal levels despite adequate relief of mitral stenosis.