Hello! Thank you for the opportunity to help you with your question!
The possible symptoms that you described are of something known as 'Deep Vein Thrombosis' or 'Deep Venous Thrombosis'.
Occasionally DVT can be very severe and effect the deep superficial veins. Some dont show any symptoms in the earlier stages until they rupture and are dislocated through the circulatory system.
The tibial vein found n the leg is a common site for DVT and the possible path for the blood clot to the coronary artery (in the heart) would be:
Tibial vein-Popliteal vein-Femoral vein-Great saphenous vein-externa iliac vein-internal iliac vein-common iliac vein-testicularis vein-renal vein-hepatic vein-pulmonary vein-pulmonary artery-coronary vein-coronary artery.
The result of it would be cancer and venous drainage from the limb may be so impaired that venous gangrene can develop. There is often an underlying cause for this event, such as an underlying cancer or clotting disorder. It can be a very difficult situation to treat. And the size of the clot is bigger, the more damage it will do.
The logic commonly used is the clots occuring waist-down must not be dangerous or life-threatening but it depends on the type and some are gravely concerning as veins carry the clot to the upper half of the body and pose risks to the well being.Please let me know if you need any clarification. I'm always happy to answer your questions.
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