Deep vein thrombosis classification scheme

Editors-in-Chief: C. Michael Gibson, M.S., M.D. Associate Editor-In-Chief: Ujjwal Rastogi, MBBS [mailto:urastogi@perfuse.org]

Overview
DVT is divided on the the basis of site of occlusion:
 * Upper extremity DVT: DVT of upper limb.
 * Lower extremity DVT: DVT of lower limb. DVT of the lower extremity is subdivided into two categories:
 * Proximal vein thrombosis.
 * Distal (calf) vein thrombosis.

Proximal vein thrombosis
Proximal vein thrombosis occurs when thrombosis involves the proximal veins like popliteal, femoral, or iliac vein. Clinically proximal vein thrombosis is of greater importance as it is more commonly associated with serious, chronic diseases like: Proximal vein thrombosis is responsible for more than ninety percent of acute Pulmonary embolism and thus higher mortality.
 * Active cancer.
 * Congestive heart failure.
 * Old age (greater than 75 years).
 * Respiratory insufficiency.

Distal vein thrombosis
Distal vein thrombosis is one in which thrombi remain confined to the deep calf veins. It is often associated with transient risk factors like travel, prolonged immobilization and recent surgery.