Natural History of Pulmonary Hypertension in Surgically Treated Patent Ductus Arteriosus
One hundred consecutive surgically treated patients with patent ductus arteriosus underwent preoperative and/or pulmonary artery and aortic pressure measurements at the time of surgery, prior to and following temporary occlusion or division of the ductus. Patients with persistent elevation in pressure following division of the ductus subsequently underwent single or multiple catheterizations at various intervals ranging between one and four years following surgery.
Pulmonary hypertension prior to division was present in 35 patients (35%). This was mild in 19, moderate in nine, and severe in seven. The pressure returned to normal immediately after division of the ductus in 13, indicating that in this group the pressure elevation was hyperkinetic. In 22, the pressure remained elevated immediately after division, pulmonary hypertension being mild in seven, moderate in eight, and severe in seven. In the mild group, the pressure subsequently returned to normal in all but one. In the moderate group, the pressure failed to return to normal in six out of eight, indicating the presence of vaso-occlusive changes in the pulmonary bed. The pressure usually exceeded 60 mm Hg systolic. In seven patients with severe pulmonary hypertension, division was performed in four. Two died in the immediate postoperative period, and two survived. Follow-up cardiac catheterization showed a return of pressure to normal in one and persistent elevation in the other. Of three patients in whom division was not performed, two are living and well two and seven years later, respectively, and one has been lost to follow-up.
Although the rate of blood flow and vaso-constriction contributed considerably to the elevation of pulmonary arterial pressure, the blood pressure failed to return to normal in the majority of patients whose systolic pressure was elevated in excess of 60 mm Hg after division of the ductus, indicating pathological pulmonary vascular alterations.
- © 1965 American Heart Association, Inc.