PROSTAGLANDIN-E1 IN PERIPHERAL VASCULAR-DISEASE - A PET STUDY OF MUSCULAR BLOOD-FLOW

Background: Increase of blood now in the ischaemic leg is believed to represent the main action of prostaglandin E-1 (PGE(1)) in the therapy of peripheral vascular disease (PVD). There is no reliable data in ma n concerning the amount of increase in muscular blood now (MBF) of the calf, and the difference between intra-arterial and intravenous appli cation. Patients and methods: We conducted a positron emission tomogra phy (PET) study of MBF with O-15-water as now tracer. Fifteen patients with PVD and three healthy volunteers were given 5 mu g PGE(1) intra- arterially over 50 min; PET scans were taken at 0, 25 and 50 min. Addi tionally, eight of the patients were investigated during an intravenou s infusion of 40 mu g PGE(1) over 120 min; PET scans were taken at 0, 30, 60 and 120 min. Results: Increase of muscular blood now by intra-a rterial PGE(1) averaged 80%. A steal phenomenon was not observed. The amount of flow enhancement depended on whether or not the femoral arte ry was patent. During intravenous PGE(1) muscular blood now remained u nchanged. Conclusions: In man, the pharmacodynamic profile of intra-ar terial PGE(1) differs clearly from intravenous PGE(1). The flow-enhanc ing property is lost during metabolization in the lung. Since no diffe rence exists between the therapeutic efficacy of intraarterial and int ravenous PGE(1) the impact on muscular blood flow is not as important as suggested previously.