Cardiac/Vascular Nurse Exam Secrets Study Guide (9 page)

Causes and risks

Risk factors for pulmonary embolism or clot formation include genetic predisposition, history of cardiovascular disease and/or family history of clot formation. Other factors that may lead to pulmonary embolism and clot formation include surgery such as hip and knee surgeries, long periods of inactivity such as prolonged bed rest or long plan or car trips, increased levels of clotting factors in the blood as associated with certain types of cancer, previous cardiovascular conditions such as heart attack or stroke, and injury to veins. The most common risk factor is the presence of deep venous thrombosis.

Additional factors that put you at high risk for pulmonary embolism include obesity, comorbid cardiovascular diseases such as high cholesterol and hypertension, pacemakers or venous catheters, pregnancy, childbirth, hormone replacement therapy and smoking.

Symptoms

The symptoms of pulmonary embolism vary depending on how much lung is involved, the size of the clot, the patient’s comorbid conditions and general health. However, many patients with pulmonary embolism are asymptotic and diagnosed during routine physical examination or when being evaluated for other conditions.

Symptoms associated with pulmonary embolism include shortness of breath; chest pain that can radiate to an individual’s arm, shoulder, neck, or jaw; chest wall tenderness; back pain; upper abdominal pain; painful respiration; cardiac arrhythmia; persistent cough with blood-streaked sputum; tachycardia; wheezing; leg swelling; clamminess; discoloration of skin including bluish-colored skin; excessive sweating; anxiety; weak pulse; lightheadedness; fainting; and/or fever.

Diagnosis and screening

Physical examination, medical history, and diagnostic tools are used to diagnose pulmonary embolism. However, the condition is difficult to diagnose because patients may present with varying symptoms and have other comorbid conditions such as respiratory or heart disease.

Diagnostic tools used to diagnose pulmonary embolism include chest x-ray, ventilation-perfusion scan, spiral computerized tomography scan, magnetic resonance imaging, ultrasound, and pulmonary angiogram. Blood tests may also be used to detect blood clots including D-dimer blood test. Other blood tests used to aid in the diagnosis of pulmonary embolism include complete blood count, lipid levels, and metabolic levels. More invasive approaches include venography. Of all these methods, most modern hospitals use computed tomography (CT) scans with intravenous (IV) contrast.

Deep venous thrombosis

Deep venous thrombosis is a condition that involves the formation of blood clots in the veins deep within the body, which can dislodge and embolize into other organ systems such as the lungs, heart, and brain. The condition mainly affects the lower legs and thigh. Deep venous thrombosis is also known as blood clots in the legs, venous thrombosis, and venous thrombus.

In the United States, the incidence of deep venous thrombosis is approximately 4.2 cases per 100,000 population per year. The incidence of deep venous thrombosis increases with age, with those over the age of 60 at higher risk.

Causes and risk factors

Risk factors for deep venous thrombosis includes prolonged sitting such as long car trips, plane trips or prolong bed rest as well as recent surgery, fractures, childbirth, and use of oral contraceptives and hormone replacement therapy. Malignancy and smoking are also important risk factors.

Individuals at higher risk for deep venous thrombosis include those with a history of deep venous thrombosis, inherited blood disorders, injury to deep vein from surgery or other trauma, slowed blood flow due to lack of physical activity, pregnancy, recent or ongoing cancer treatment, central venous catheter, obesity, and age over 60.

Deep venous thrombosis can be caused by damage to the vein’s inner lining due to physical, chemical or biochemical factors such as surgery, injury, inflammation, or immune response. Other causes include hindered blood flow and more-viscous blood.

Symptoms

The symptoms of deep venous thrombosis include pain in 1 leg, tenderness in 1 leg, swelling of 1 leg, increased heat or warmth in 1 leg, and discoloration of skin color in 1 leg.

Individuals with deep venous thrombosis may also present with pulmonary embolism. Symptoms of pulmonary embolism include unexplained shortness of breath, pain with deep breathing, coughing up blood, and tachycardia.

A majority of patients diagnosed with deep venous thrombosis may also present with tendonitis, arterial insufficiency, arthritis, asymmetric peripheral edema, cellulites, hematoma, lymphedema, soft tissue injury, neurogenic pain, and postphlebitic syndrome.

Diagnosis and screening

Physical examination, medical history, and diagnostic testing are used to diagnose deep venous thrombosis. Upon physical examination, practicing clinicians may recommend a patient for further diagnostic testing when deep venous thrombosis is suspected.

Diagnostic testing tools include venography, Doppler ultrasound of leg in question, nuclear medicine imaging studies, magnetic resonance imaging, impedance plethysmography of leg, and D-dimer blood test. Other blood tests to evaluate the presence of blood clots include antithrombin III, protein C, protein S, factor V Leiden, prothrombin 2020a mutation, disseminated intravascular coagulation (DIC) test, and lupus anticoagulant and anticardiolipin antibodies.

Venous insufficiency

Venous insufficiency is a condition that involves abnormal blood flow through the veins, which can lead to complications such as heart failure and sudden death. Typically, the condition occurs when veins in the legs do not properly send blood back to the heart. Venous insufficiency can be associated with deep venous thrombosis, varicose veins and static dermatitis and ulcers.

The risk of venous insufficiency increases with age, with women over the age of 50 at highest risk for developing the condition. In the United States, the prevalence of venous insufficiency ranges from 7% to 60% on average.

Causes and risk factors

Patients diagnosed with venous insufficiency are also at risk for skin color changes around the ankles, redness of legs and ankles, thickening of skin on legs and ankles, and ulcers on the legs and ankles.

The most common risk factor for venous insufficiency is deep venous thrombosis. Other risk factors include natural aging, pregnancy, limited physical activity, smoking, sitting for long periods of time, obesity, phlebitis, family history, medical history of cardiovascular disease, and presence of other comorbid conditions. Blood pressure that is higher than normal in the leg can also lead to venous insufficiency.

Symptoms

The symptoms of venous insufficiency can vary based on the extent and degree of disease. However, some patients present with few or no symptoms. Also, symptoms may mimic other conditions and should be evaluated by a clinical practitioner to eliminate the presence of other comorbid conditions.

Common symptoms include throbbing, cramping, burning sensations, fatigue, ulcerations that do not heal, varicose veins, fluid retention and skin changes and discoloration in the legs. Other symptoms include pain that improves when raising the legs, but gets worse when standing as well as dull, aching, heaviness, and/or cramping in the legs. Varicose veins are complications that can lead to death if they rupture and bleed.

Diagnosis and screening

Physical examination, medical history, and diagnostic tools are used to diagnose venous insufficiency. Newer guidelines recommend the use of standard diagnostic tools. Practicing clinicians may use a clinical scoring system that rates signs and symptoms of venous insufficiency. The scoring system ranks 5 symptoms including pain, cramps, heaviness, pruritus, and paresthesia; and 6 signs including edema, hyperpigmentation, induration, venous ectasia, redness, pain and calf compression on a scale of 0 to 3, with 3 being most severe. Scores of 5 to 14 on 2 visits greater than 6 months apart indicate mild to moderate disease and scores greater than 15 indicate severe disease.

Valvular disease

Valvular disease is a condition that affects 1 of the 4 main cardiac valves including the aortic, tricuspid, mitral, and pulmonic valves.

Valvular stenosis is a condition that involves narrowing, stiffening, thickening, and/or blockage of 1 or more of the heart valves. Depending on the valve site, the condition can be referred to as aortic stenosis, tricuspid stenosis, mitral stenosis and/or pulmonic stenosis.

Valvular regurgitation is a condition that occurs when blood leaks back through the valve in the wrong direction due to improper closing of 1 or more of the cardiac valves. Depending on the valve site, the condition can be referred to as aortic regurgitation, tricuspid regurgitation, mitral regurgitation, and/or pulmonic regurgitation.

Valvular disease accounts for approximately 20,000 deaths in the United States annually. It is also considered a contributing factor to increased mortality in over 40,000 individuals annually. The majority of patients with valvular disease leading to death have aortic valve dysfunction, accounting for over 60% of cases, with over 10% having a contribution from mitral valve dysfunction. Deaths due to tricuspid and pulmonic valve dysfunctions are uncommon. Pregnant women with valvular disease are at higher risk for complications to the mother and fetus. Women aged 75 years or older are at an increased risk for developing atherosclerosis and potentially valvular disease than men of the same age group.

Causes and risk factors

The causes of valvular disease can be a combination of genetic and environmental factors. The most common cause of valvular disease is congenital defects and infections such as rheumatic fever and Marfan syndrome.

Diseases or other disorders that can lead to valvular disease include damage and scar tissue due to heart attack, endocarditis, other infections, high blood pressure, heart failure, and/or atherosclerosis. Other conditions that have been associated with valvular disease include systemic lupus erythematosus, cardiomyopathy, syphilis, hypertension, aneurysms, connective tissue disorders, carcinoid syndrome, metabolic disorders, diet medications, and radiation therapy.

Individuals at highest risk for developing valvular disease include those with comorbid cardiovascular diseases such as congestive heart failure, those older than 65 years of age, those with endocarditis and/or rheumatic fever.

Symptoms

The severity of symptoms associated with valvular disease depends on the extent and degree of the disease and the particular valves affected. However, patients with severe disease may present with few or no symptoms, while patients with more mild disease may have symptoms that are more extensive.

Gradual progression of valvular disease typically presents with fewer symptoms than sudden onset of valvular disease. Symptoms that can be associated with valvular disease include chest pain, palpitations, loss of breath, fatigue, fainting, swelling of ankles, feet or abdomen, weakness, dizziness and rapid weight gain.

Diagnosis and screening

The diagnosis of valvular disease can be difficult, especially when patients present with few or no symptoms. Most patients are diagnosed during routine physical examination or when examining the patient for other conditions.

Physical examination, medical history, and diagnostic tools are used to diagnose valvular disease. Practicing clinicians examine the patient for abnormal heart sounds such as murmur, evidence of heart enlargement and fluid buildup in the lungs.

Diagnostic tools used to screening for valvular disease include electrocardiogram, echocardiography, magnetic resonance imaging, and chest x-ray. Other diagnostic tests to rule out any other comorbid cardiovascular conditions include cardiac catheterization and cardiac stress testing.

Atresia and mitral valve prolapse

Atresia is a condition where 1 or more of the cardiac valves fail to develop properly and there is a small or no opening between the respective chambers. Depending on the valve site, the condition can be referred to as aortic atresia, tricuspid atresia, pulmonic atresia, and/or mitral atresia. Aortic atresia is often associated with a patent ductus arteriosus and, sometimes, coarctation of the aorta.

Mitral valve prolapse is a very common condition characterized by excessive retrograde movement of 1 or both mitral valve leaflets. It often is associated with regurgitation through the mitral valve due to anatomical defects in the valve flaps. It occurs in 1% to 2% of the population in the United States, affecting men and women equally. In most cases, the condition is considered benign with few or no symptoms. However, in some cases, it can lead to more-serious complications and various symptoms. Rarely, it is secondary to rheumatic carditis, Marfan syndrome, or ruptured chorda tendinea.

Cardiac vasospasm

Vasospasm is a condition that occurs when blood vessels spasm leading to vasoconstriction. The condition can cause ischemia, blood clot formation, hemorrhage, stroke, aneurysm, heart attack, and sudden death. The genetic and/or environmental factors that contribute to vasospasm remain vague and a combination of factors is usually the cause of vasospasm. Some patients present with few or no symptoms, while others present with more symptoms.

Cardiac vasospasm can be treated with lifestyle modifications, pharmacologic management and, in more severe cases, surgery. Pharmacologic approaches include nitrates such as nitroglycerin, isosorbide dinitrate and isosorbide mononitrate, and calcium channel blockers such as nifedipine, amlodipine, verapamil, and diltiazem.