PHLECO: a multicenter study of the fate of 1647 hospital patients treated conservatively without fibrinolysis and surgery
The PHLECO Study (phlebothrombosis conservative therapy) is a multicenter investigation of patients with deep vein thrombosis receiving conservative nonfibrinolytic hospital treatment. A second study (part II : PHLEFI, phlebothrombosis fibrinolytic treatment) to be published later deals with the outcome of fbrnolytic therapy. In both studies the incidence of life-threatening sequelae, such as pulmonary embolism, is of major interest. The 49 medical departments participating in the study mailed the relevant data to the Duisburg Coordination Center for further data analysis and the following information was gained: (a) In descending order of frequency, the clinical conditions of thrombosis were: immobility, postoperative status, malignancy, hormone treatment, posttraumatic conditions, and pregnancy. (b) In descending order of frequency, the sites of thrombosis were: femoral vein, calf vein, iliac vein, popliteal vein, and subclavian vein. Left-sided thrombosis predominated in the iliac and subclavian vein groups. (c) In descending order of frequency, the treatment regimens employed were: intravenous heparin+ oral anticoagulants, intravenous heparin+subcutaneous heparin, intravenous heparin alone, subcutaneous heparin alone, intravenous heparin+subcutaneous heparin+oral anticoagulants, subcutaneous heparin+oral anticoagulants, intravenous heparin + platelet aggregation inhibitors. (d) The average hospital stay was 23.7 + 15.6 days. No correlation existed between duration of hospital stay and particular types of therapy. (e) The incidence of nonfatal pulmonary embolism was 16.1% while that of fatal pulmonary embolism was 2.33%. (f) Women outnumbered men in the group with fatal pulmonary embolism, and the death rate among older patients was higher than that among younger patients. (g) Patients with fatal pulmonary embolism had a shorter history of thrombosis than patients in the unselected cohort (patients with and without pulmonary embolism). (h) Iliac vein thrombosis correlated with the highest incidence of fatal pulmonary embolism, with the right iliac vein predominating. (i) Calf vein thrombosis produced pulmonary embolism only very rarely, and pulmonary embolism was not observed in the group of patients with subclavian vein thrombosis.