Pharmacoangiography in the diagnosis of recurrent massive lower gastrointestinal bleeding.

The source of recurrent massive lower gastrointestinal bleeding can sometimes escape detection by conventional diagnostic measures. In such situations, bleeding can be directly provoked by pharmacoangiography using vasodilators, anticoagulants, and/or fibrinolytic agents. Heparin, streptokinase, and tolazoline, used separately or in combination, can augment, prolong, or reactivate transient, covert bleeding, thereby facilitating angiographic identification and localization of the lesion. Physiological, clinical, and angiographic factors are discussed. Although rarely needed, this useful and sometimes crucial diagnostic approach demands the combined skills and support of the radiologist, clinician, and surgeon.