cardiac thrombosis


thrombosis

(throm-bo'sis) [ thrombo- + -osis] The formation or presence of a blood clot within the vascular system. This is a life-saving process when it occurs during hemorrhage. It is a life-threatening event when it occurs at any other time because the clot can occlude a vessel and stop the blood supply to an organ or a part. The thrombus, if detached, can travel through the bloodstream and occlude a vessel distant from the original site; e.g., a clot in the leg may break off and cause a pulmonary embolus.

Etiology

Trauma (particularly after an operation and parturition), cardiac and vascular disorders, obesity, hereditary coagulation disorders, age over 65, an excess of erythrocytes and of platelets, an overproduction of fibrinogen, and sepsis are predisposing causes.

Symptoms

Lungs: Obstruction of the smaller vessels in the lungs causes an infarct that may be accompanied by sudden pain in the side of the chest, similar to pleurisy; also present are the spitting of blood, a pleural friction rub, and signs of consolidation. Kidneys: Blood appears in the urine. Skin: Small hemorrhagic spots may appear in the skin. Spleen: Pain is felt in the left upper abdomen. Extremities: If a large artery in one of the extremities, such as the arm, is suddenly obstructed, the part becomes cold, pale, bluish, and the pulse disappears below the obstructed site. Gangrene of the digits or of the whole limb may ensue. The same symptoms may be present with an embolism.

If the limb is swollen, one should watch for pressure sores. Burning with a hot water bottle or electric pad should be guarded against. Prolonged bedrest may be necessary, depending on the patient's condition.

Treatment

Pathological clots are treated with thrombolytic agents (such as streptokinase), antiplatelet drugs (such as heparins or aspirin), anticoagulants (such as warfarin), or platelet glycoprotein receptor antagonists (such as abciximab). When a thrombus or embolus is large and life threatening, surgical removal may be attempted.

cardiac thrombosis

Coronary occlusion.

catheter-associated thrombosis

A thrombosis that forms around a central venous catheter or the electrical leads of a defibrillator or pacemaker.

cerebral sinovenous thrombosis

A thrombosis in one of the main veins that carry blood from the brain, such as the superior sagittal sinus, the lateral sinus, or the straight sinus.

coagulation thrombosis

Thrombosis due to coagulation of fibrin in a blood vessel.

coronary thrombosis

Coronary occlusion.

deep vein thrombosis

, deep venous thrombosis Abbreviation: DVT
A thrombosis in one or more of the deep veins of the legs (the most common site) or the veins of arms, pelvis, neck, axilla, or chest. The clot may damage the vein or may embolize to other organs, e.g., the heart or lungs. Such emboli are occasionally fatal. See: pulmonary embolism

Etiology

DVT results from one or more of the following conditions: blood stasis, e.g., bedrest; endothelial injury, e.g., after surgery or trauma; hypercoagulability, e.g., factor V Leiden or deficiencies of antithrombin III, protein C, or protein S; congestive heart failure; estrogen use; malignancy; nephrotic syndrome; obesity; pregnancy; thrombocytosis; or many other conditions. DVT is a common occurrence among hospitalized patients, many of whom cannot walk or have one or more of the other risk factors just mentioned.

Symptoms

The patient may report a dull ache or heaviness in the limb, and swelling or redness may be present, but just as often patients have vague symptoms, making clinical diagnosis unreliable.

Diagnosis

Compression ultrasonography is commonly used to diagnose DVT (failure of a vein to compress is evidence of a clot within its walls). Other diagnostic techniques include impedance plethysmography and venography.

Treatment

Unfractionated heparin or low molecular weight heparin (LMWH) is given initially, followed by several months of therapy with an oral anticoagulant such as warfarin. The duration of therapy depends on whether the patient has had previous thrombosis and whether, at the end of a specified period of treatment, the patient has an elevated D-dimer level: patients with increased D-dimers after several months of treatment with anticoagulants are more likely than other patients to have recurrent clots if their anticoagulant regimen is discontinued..

Complications

Pulmonary emboli are common and may compromise oxygenation or result in frank cardiac arrest. Postphlebitic syndrome, a chronic swelling and aching of the affected limb, also occurs often.

Prevention

In hospitalized patients and other immobilized persons, early ambulation, pneumatic compression stockings, or low doses of unfractionated heparin, LMWH, or warfarin may be given to reduce the risk of DVT.

effort thrombosis

Paget-Schreutter syndrome

embolic thrombosis

Thromboembolism.

hepatic vein thrombosis

An often fatal thrombotic occlusion of the hepatic veins, marked clinically by hepatomegaly, weight gain, ascites, and abdominal pain. Synonym: Budd-Chiari syndrome

infective thrombosis

Thrombosis in which there is bacterial infection.

marasmic thrombosis

Thrombosis due to wasting diseases.

mural thrombosis

Mural thrombus.

placental thrombosis

Thrombi in the placenta and veins of the uterus.

plate thrombosis

Thrombus formed from an accumulation of platelets.

postpartum ovarian vein thrombosis

A relatively rare, but potentially severe complication of some deliveries, e.g., caesarean births, and of pelvic inflammatory disease, in which one (typically the right) or both ovarian veins becomes clotted and infected. Common findings are abdominal pain, fever, nausea, and, often, a localized mass on physical assessment of the patient. The disorder is usually treated with anticoagulants and antibiotics although surgical excision of the clot is sometimes needed.

puerperal thrombosis

Coagulation in veins following labor.

septic thrombosis

An infected blood clot usually found in the heart or the venous sinuses of the brain.

sinus thrombosis

Formation of a blood clot in a venous sinus.

stent thrombosis

A blood clot that forms inside a device inserted into a blood vessel to keep that vessel open.

Patient Care

Stents are deployed in completely obstructed or partially blocked arteries to keep blood flowing through them to the organs they supply. When this blood flow stops due to clotting within the stent, the organ may become ischemic and die. To reduce the risk of clotting within a stent, patients use antiplatelet drugs, like aspirin, dipyridamole, or clopidogrel, and medications to lower serum lipid levels. Tobacco cessation, and healthy lifestyle changes (eating lighter, exercising regularly) may also be helpful.

traumatic thrombosis

Thrombosis due to a wound or injury of a part.

venous thrombosis

Thrombosis of a vein.