Fibrinolytic activity in the walls of cerebral saccular aneurysms.

The fibrinolytic activity of 28 cerebral saccular aneurysms from 24 patients and of controls consisting of 10 cerebral arteries has been studied by Todd's autography technique. An increased activity was seen in the minute adventitial vessels and in the endothelium in ruptured cerebral saccular aneurysms, but the aneurysms showed somewhat less activity than the surrounding arteries. Seven patients with subarachnoid haemorrhage had the same increase in fibrinolytic activity in the aneurysmal wall despite antifibrinolytic therapy ante mortem. This finding has been discussed.