The decreased mobility of the patient with cardiac disease and the impaired circulation that accompany these disorders contribute to the development of intracardiac and intravascular thrombosis. Intracardiac thrombus is especially common in patients with atrial fibrillation, because the atria do not contract forcefully and blood flow slows through the atrium, increasing thrombus for-mation. Intracardiac thrombus is detected by an echocardiogram and treated with anticoagulants, such as heparin and warfarin (Coumadin). A part of the thrombus may become detached (embolus) and may be carried to the brain, kidneys, intestines, or lungs. The most common problem is pulmonary embolism. The symptoms of pulmonary embolism include chest pain, cyanosis, shortness of breath, rapid respirations, and hemoptysis (bloody sputum).
The pulmonary embolus may block the circulation to a part of the lung, producing an area of pulmonary infarction. Usually, there is a significant decrease in oxygenation measured by arterial blood gas analysis or pulse oximetry. Pain experienced is usually pleuritic; it increases with respiration and may subside when the patient holds the breath. Cardiac pain is usually continuous and does not vary with respirations. However, it may be difficult to differentiate by symptoms alone. The patient usually undergoes a ventilation-perfusion scan or a pulmonary arteriogram for definitive diagnosis.
Systemic embolism may manifest as cerebral, mesenteric, or renal infarction; an embolism can also compromise the blood supply to an extremity The nurse must be aware of such possible complications and be prepared to identify and report signs and symptoms.