Lippincott Williams & Wilkins

When a DVT occurs, it occludes the lumen of the vein; this causes a “build-up” of pressure “behind” the clot; that is, more distal to the clot; most DVTs form in the calf, but they often “grow” or “elongate” or “propagate” proximally to the popliteal vein or femoral vein, or even up to the iliac vein; ................
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