The clinical picture of deep vein thrombosis correlated to the frequency of pulmonary embolism.

Pain and swelling of the leg have been studied in 27 patients with deep vein thrombosis (DVT). Twenty-three of them were also examined for pulmonary embolism (PE) after one week of heparin treatment. Scoring systems were constructed to quantitate pain, size of DVT and PE. A ratio between swelling and pain (S/P ratio) was calculated for each patient. Actual size of the DVT, as estimated with venous phlebography, was correlated to swelling (rs = 0.51, p less than 0.01), S/P ratio (rs = 0.53, p less than 0.01) and PE (rs= 0.57, p less than 0.01). DVTs with not pain at all or just tenderness on palpation were more often associated with PE (p less than 0.05) and elevated blood pressure (p = 0.02) than DVTs with pain on walking. A free floating proximal end of DVT proved unreliable for predicting PE. It is concluded that the risk of developing PE depends not only on DVT size, but also on factors related to pain.