Cardiac/Vascular Nurse Exam Secrets Study Guide (6 page)

Other contributing factors include socioeconomic factors such as lack of education and lower income that prevent individuals from seeking preventative care and/or routine management.

Symptoms

Symptoms associated with myocardial infarction include chest pain, pain radiating from the left side of the neck or arm, feeling of fullness or pressure in the chest, prolonged pain in upper abdomen, syncope, lightheadedness, dizziness, shortness of breath, nausea, vomiting, palpitations, sweating, weakness, fatigue, and anxiety. Some patients present with no symptoms, which is referred to as a silent heart attack. Also, men present with different symptoms than women in most cases. Women tend to present with shortness of breath, fatigue, and weakness.

The onset of symptoms typically occurs over a short period of time, worsening without intervention. However, nearly half of patients do not experience any symptoms such as chest pain or shortness of breath.

Diagnosis and screening

Physical examination, patient history, and diagnostic tools are used for diagnosis of myocardial 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 prevention of complications and death. Physical examination, patient feedback, and diagnostic tools are used to diagnose an acute stroke. Screening tools used to diagnose a stroke include carotid ultrasonography, arteriography, computerized tomography, magnetic resonance imaging, and echocardiography. Practicing clinicians may also perform blood work to assess other comorbid conditions that may have contributed to the stroke including lipids, glucose and homocysteine levels.

More invasive approaches such as angiography may be performed to assess the degree and extent of cardiovascular disease.

Peripheral arterial disease

Peripheral arterial disease is a condition in which blood flow is reduced to limbs and extremities. The prevalence of peripheral arterial disease increases with age, with individuals over the age of 55 having a prevalence of 10% to 25%. In the United States, approximately 10% to 20% of individuals 65 years or older are affected by peripheral arterial disease.

Most patients diagnosed with peripheral arterial disease are asymptomatic, with approximately 70% to 80% presenting with no symptoms upon diagnosis. However, the incidence of symptomatic peripheral arterial disease increases with age. Yet, the prevalence of symptomatic peripheral arterial disease varies based upon disease definition and age of patient population being evaluated.

Causes and risks

Atherosclerosis is the main cause of peripheral arterial disease. However, blood clots, injury to limbs, unusual anatomy of ligaments or muscles or infection may lead to peripheral arterial disease. Other diseases that can lead to onset of peripheral vascular disease include aortic aneurysms, Buerger’s disease, pulmonary embolism, phlebitis, varicose veins, and Raynaud’s syndrome.

Factors that increase an individual’s risk for peripheral arterial disease include smoking, 50 years of age or older, diabetes, obesity, high blood pressure, high cholesterol or family history of cardiovascular diseases and/or atherosclerosis. Male individuals of African American descent as well as overweight individuals and those with a family history of cardiovascular disease are at a higher risk of peripheral vascular disease.

Other risk factors under clinical investigation include inflammatory mediators such as C-reactive protein, homocysteine, and fibrinogen.

Symptoms

More than half of individuals diagnosed with peripheral arterial disease do not present with symptoms. However, symptoms associated with peripheral arterial disease include leg numbness or weakness, cold legs and feet, sores or wounds on digits or extremities that will not heal, blue or pale hue to legs, feet, hands and/or arms, hair loss on feet and legs and changes in composition of nails.

Approximately one-third to one-half of individuals diagnosed with peripheral arterial disease present with intermittent claudication. Intermittent claudication is defined as muscle pain or cramping in appendages triggered by walking and physical activity. Individuals may also experience ischemic rest pain.

Diagnosis and screening

Early diagnosis of peripheral arterial disease is necessary for prevention of complications such as cardiovascular disease, heart attack, stroke, and sudden death. Physical examination and diagnostic screening tools are used to determine if a patient has peripheral arterial disease.

Upon physical examination, practicing clinicians use a stethoscope to determine the presence of bruits. They also look for evidence of poor wound healing, sores, color changes, temperature changes, and decreased blood pressure in limbs. Diagnostic screening tools include the ankle-brachial index and angiography. Additional tests include angiography, electrocardiogram, magnetic resonance angiography, blood tests, and ultrasound.

Inflammation

Inflammation is defined as a complex response of vascular tissues to irritants, pathogens, and/or damaged cells. It is a protective mechanism to remove harmful substances from the body and initiate the healing signal transduction cascade.

Inflammation can be classified as either acute or chronic. Acute inflammation is defined as the initial response by the body to irritants, pathogens, and/or damaged cells, recruiting neutrophils, monocytes, and macrophages from blood to affected tissue. Chronic inflammation is prolonged inflammation that is a process that recruits other cells such as monocytes, macrophages, lymphocytes, plasma cells, and fibroblasts involved in the pathogen removal and healing process.

Acute inflammation is caused by pathogens, irritants and/or damaged cells. The major cells involved in the acute inflammation process include neutrophils, monocytes, and macrophages. The primary mediators include vasoactive amines and eicosanoids. The onset of action of acute inflammation is immediate and lasts for approximately a few days. The initiation of acute inflammation leads to healing, abscess formation, and chronic inflammation stimulation.

Chronic inflammation is triggered by acute inflammation due to presence of pathogens, irritants and/or damaged cells and the body’s reaction to these initial triggers. The presence of neutrophils, monocytes, and pathogens as well as other signaling transduction mechanisms trigger chronic inflammation. The major cells involved in the chronic inflammation process include monocytes, macrophages, lymphocytes, plasma cells, and fibroblasts. The primary mediators include cytokines, growth factors, reactive oxygen species, and hydrolytic enzymes. The onset of action of chronic inflammation is delayed and lasts for approximately several months or years. The initiation of chronic inflammation leads to tissue destruction and fibrosis.

Causes and risk factors

The causes of acute inflammation include presence of irritants, pathogens and/or damaged cells within the body. Acute inflammation is characterized by vascular changes including vasodilation, increased permeability, and/or reduced blood flow. The signaling cascades involved in acute inflammation include the complement system such as C3, C5a, membrane attack complex and thrombin, kinin system such as bradykinin, coagulation system such as thrombin and fibrinolysis system such as plasmin.

The cause of chronic inflammation is persistent acute inflammation due to bacterial infection, chemical exposure including silica exposure and/or autoimmune reactions as in rheumatoid arthritis, lupus, or psoriasis.

Symptoms

The symptoms of acute inflammation include swelling of joints and muscles, joint and muscle stiffness, redness, pain, heat and loss of function. Chronic inflammation is sometimes characterized by the same symptoms as acute inflammation. However, fever, chills, fatigue, low energy, headaches, appetite loss and muscle stiffness may characterize chronic inflammation.

Involvement of internal end organ systems may present with symptoms specific to that organ system. Involvement of the cardiovascular system may lead to chest pain, palpitations, hypertension, and/or high cholesterol. Involvement of the respiratory system may lead to asthma and/or allergic reactions. Involvement of the renal system may lead to kidney failure and/or infections. Involvement of the large intestines may lead to ulcerative colitis, Crohn disease, diverticulitis, and/or inflammatory bowel disease.

Diagnosis and screening

Inflammatory diseases are diagnosed after careful physical examination and use of diagnostic tools. Practicing clinicians will complete a physical examination and take an individual’s medical history as well as family history of inflammatory disorders. They will examine painful joints, muscles and other organ systems. They will also examine and discuss the presence of other comorbid conditions.

Diagnostic screening tools used include x-rays, magnetic resonance imaging, CT scans, as well as other imagining techniques to assess impact on end organ systems including cardiovascular system, respiratory system, renal system and gastrointestinal system.

Pericarditis

Pericarditis is defined as inflammation of the pericardium, which is the thin membrane surrounding the heart muscle. Excess fluid can accumulate between the 2 layers of the membrane, impacting the proper function of the heart. There are 2 types of pericarditis including acute pericarditis and chronic pericarditis. Acute pericarditis is more prevalent than chronic pericarditis.

The condition is more prevalent among men than women between the ages of 20 to 50. Acute pericarditis episodes can last from 1 to 3 weeks, but additional episodes can occur in the future. Approximately 20% of individuals with pericarditis may have a reoccurrence within 1 month of the first episode.