Cardiac/Vascular Nurse Exam Secrets Study Guide by Mometrix Media Read Free Book Online

infarction. Diagnostic tools include echocardiogram, electrocardiogram, chest x-ray, nuclear ventriculography, magnetic resonance imaging (MRI), and blood tests to detect elevation in cardiac markers. More invasive diagnostic tools used for diagnosis of myocardial infarction and atherosclerosis include angiography and angioplasty.
     
    The World Health Organization criteria used to diagnose myocardial infarction include clinical history of ischemic type chest pain lasting more than 20 minutes, changes in electrocardiogram tracing and rise and fall of serum cardiac markers such as creatinine kinase-MB fraction and troponin I. Individuals that present with 2 or more of these criteria are typically diagnosed with having experienced a myocardial infarction.
     

Stroke
     
    Stroke is defined as an acute condition where blood flow, and thus oxygen, to the brain is hindered or significantly reduced. There are 2 types of stroke including ischemic stroke and hemorrhagic stroke. Ischemic stroke is defined as a condition where blood flow to the brain is blocked because of blood clot formation or embolism. Approximately 80% to 85% of strokes are ischemic strokes, while 15% to 20% are hemorrhagic strokes. Another type of stroke is a transient ischemic attack, where blood flow to the brain is temporarily hindered.
     
    In the United States, approximately 400,000 individuals are diagnosed with stroke per year, which is expected to increase on a yearly basis because of the aging of the U.S. population.
     
    In the United States, stroke is the third leading cause of death annually following cancer and cardiovascular diseases. It is also the leading the cause of adult disability in the United States.
     

Ischemic and hemorrhagic stroke
    Ischemic strokes include thrombotic strokes, which occur when a blood clot forms in arteries supplying the brain, and embolic stroke, which occurs when a blood clot (or other embolus, like a cholesterol plaque) formed in the cardiovascular system dislodges and blocks more distal arteries.
     
    Hemorrhagic stroke occurs when a blood vessel ruptures and leaks into the brain. Hemorrhagic stroke includes intracerebral hemorrhage, which occurs when a blood vessel in the brain ruptures hindering blood flow and damaging tissue and subarachnoid hemorrhage, which occurs when a blood vessel lining the brain membrane bursts and leaks into the subarachnoid space.
     

Causes and risk factors
    Patients at highest risk for an acute stroke are those individuals who have experienced a transient ischemic attack or experienced a previous stroke. Other risk factors include family history, natural aging, African American descent, hypertension, high cholesterol, cigarette smoking, diabetes, cardiovascular disease, alcoholism, illicit drug use, stress, anxiety, and elevated homocysteine levels.
     
    Drugs may also increase an individual’s risk of stroke including birth control pills and hormone replacement therapy. Furthermore, men are at a higher risk for stroke than women. The aged are especially at an increased risk with nearly 75% of strokes occurring individuals 65 years of age or older.
     

Symptoms
    Patients experiencing an acute stroke typically present with sudden numbness or weakness of the arms, legs, and/or face, which occurs on 1 side of the individual’s body. They also may experience confusion, slurred speech, difficulty speaking, vision loss, double vision, difficulty walking, dizziness, loss of balance, loss of coordination, pain, memory loss, problems with spatial orientation, perception loss, and severe headache of sudden onset.
     
    Most patients who present with symptoms of stroke do not present with warning symptoms aside from the acute attack. However, in some cases, individuals may experience a transient ischemic attack with similar symptoms of an acute attack prior to experiencing an acute stroke.
     

Diagnosis and screening
    Early recognition of signs and symptoms of stroke is very important for