What is the leading cause of death worldwide?
Cardiovascular disease is the leading cause of death worldwide.
What is a varicose vein?
A varicose vein is a superficial vein in which blood has pooled.
Which veins do varicose veins typically involve, and what are their characteristics?
Varicose veins typically involve the saphenous veins of the legs and are distended, tortuous, and palpable.
What are the two causes of varicose veins?
Varicose veins are caused by (1) trauma to the saphenous veins that damages one or more valves, or (2) gradual venous distention caused by the action of gravity on blood in the legs.
How does the muscular pump in the legs normally function in relation to venous blood flow?
Normally the muscular pump in the legs moves venous blood up toward the heart, and valves prevent backflow and pooling of blood.
What happens to venous valves in individuals who habitually stand for long periods, wear constricting garments, or cross their legs at the knees?
In individuals who habitually stand for long periods, wear constricting garments, or cross the legs at the knees, distention progresses until the pressure in the vein damages venous valves, rendering the valves incompetent.
What effect do damaged valves have on venous pressure?
Damaged valves cannot maintain normal venous pressure, which causes hydrostatic pressure in the vein to increase.
What is chronic venous insufficiency (CVI), and how does it relate to varicose veins?
Varicose veins can progress to chronic venous insufficiency (CVI), which is defined as sustained inadequate venous return.
What is the pathological progression that leads from venous hypertension to ulceration?
Venous hypertension, circulatory stasis, and tissue hypoxia lead to an inflammatory reaction in vessels and tissue. This causes fibrosclerotic remodeling of the skin and then ulceration.
How does sluggish circulation to the extremities lead to venous stasis ulcers?
Circulation to the extremities can become so sluggish that the metabolic demands of the cells for oxygen, nutrients, and waste removal are barely met. Any trauma or pressure can therefore lower the oxygen supply and cause cell death and necrosis (venous stasis ulcers).
How does treatment of varicose veins and CVI typically begin, and what are examples of noninvasive treatments?
Treatment of varicose veins and CVI begins conservatively, and wound healing often occurs following noninvasive treatments, such as leg elevation, compression stockings, and physical exercise.
What are the new management techniques for treatment of varicose veins?
New management techniques include endovenous ablation (radiofrequency and laser) and ultrasound-guided foam sclerotherapy.
What are other management techniques for varicose veins that are less safe?
Other management techniques for managing varicose veins are surgical ligation and vein stripping, which are less safe.
What is a thrombus?
A thrombus is a blood clot that remains attached to a vessel wall.
What is a thromboembolus?
A detached thrombus is a thromboembolus.
Why are venous thrombi more common than arterial thrombi?
Venous thrombi are more common than arterial thrombi because flow and pressure are lower in the veins than in the arteries.
What is deep venous thrombosis (DVT), and what complication may result from it?
Deep venous thrombosis (DVT) refers to clot formation in the large veins, primarily of the lower extremities and may result in venous thromboembolism (VTE) to the pulmonary circulation.
What are the three factors (triad of Virchow) that promote venous thrombosis?
Three factors (triad of Virchow) promote venous thrombosis: (1) venous stasis (e.g., immobility, obesity, prolonged leg dependency <e.g., air travel>, age, heart failure <HF>), (2) venous endothelial damage (e.g., trauma, medications), and (3) hypercoagulable states (e.g., inherited disorders, malignancy, pregnancy, oral contraceptives, hormone replacement, hyperhomocysteinemia, antiphospholipid syndrome).</HF>
Who is at significant risk for DVT, and which hospitalized patients have particularly high risk?
Virtually everyone who is hospitalized is at significant risk for DVT, especially those with orthopedic trauma or surgery, spinal cord injury, and obstetric/gynecologic conditions.
When should inherited hypercoagulability states be suspected?
Inherited hypercoagulability states should be suspected in individuals who develop thrombi in the absence of the usual risk factors.
What leads to thrombus formation in the vein, and where does it often occur?
Accumulation of clotting factors and platelets leads to thrombus formation in the vein, often near a venous valve.
Why may a blood clot present as localized inflammation and swelling?
A blood clot may present as localized inflammation and swelling because the clot is causing backup and leaking into the surrounding tissues.
What typically happens to most thrombi, and what is the risk associated with untreated DVT?
Most thrombi eventually dissolve without treatment, but untreated DVT is associated with a high risk of thromboembolization of a part of the clot from the leg to the lung (pulmonary embolism).
What is post-thrombotic syndrome (PTS), and what proportion of individuals with DVT may develop it?
In up to one third of individuals with DVT, persistent venous outflow obstruction may lead to post-thrombotic syndrome (PTS), a frequent complication of DVT characterized by chronic, persistent pain; edema; and ulceration of the affected limb.
