Assessment of total thrombus load in symptomatic patients with venous thromboembolism

Pulmonary embolism (PE) and Deep vein thrombosis (DVT) are separate but related aspects of the same dynamic process termed as venous thrombembolism (VTE). The existing Asian literature has shown a wide variation in the prevalence of VTE, with very limited data from the Indian subcontinent. Between January 2001 and July 2004, 1552 patients with clinically suspected lower limb DVT underwent a combined ascending radionuclide venogram and lung perfusion scan for assessment of the total thrombus burden. Of 744 patients with radionuclide venography proven DVT, 294 (40%) had a high probability lung scan. Nearly half of these patients were asymptomatic for pulmonary embolism. The high prevalence of PE in patients with DVT suggests the need for evaluation of thrombus load in the venous as well as pulmonary circulation. A combination radionuclide ascending venography with lung perfusion scan is a useful and reliable single test for this purpose.