Cardiac/Vascular Nurse Exam Secrets Study Guide (11 page)

Symptoms

The symptoms of Wolff-Parkinson-White syndrome include rapid heart rate and abnormal electrocardiogram. Patients diagnosed with the condition may have a few episode of increased heart rate, while others may present with more consistent episodes of increased heart rate, as much a few times per week. Symptoms may also vary from patient to patient and may vary in terms of severity. Cardiovascular comorbid conditions may further affect the symptoms that present in patients who are diagnosed with the syndrome.

The most common symptoms associated with the syndrome include cardiac palpitations, lightheadedness, fainting, confusion, dizziness, shortness of breath, chest pain, chest tightness, fluttering in chest, anxiety, sweating, inability to perform activities of daily living, fatigue, physical activity intolerance, and hypotension. Wolff-Parkinson-White is one of the most common causes of tachycardia in infants and children.

Diagnosis and screening

Physical examination, medical history, and diagnostic tools are used to screen for Wolff-Parkinson-White syndrome. Upon physical examination, practicing clinicians will look for rapid or irregular heart rate of varying heart rate and/or hypotension.

Diagnostic screening tools used to confirm diagnosis of Wolff-Parkinson-White syndrome include electrocardiogram, Holter monitor, event recorders, and electrophysiologic testing and mapping.

Ventricular fibrillation

Ventricular fibrillation is a very serious condition caused by uncoordinated contractions of cardiac muscle in the ventricles of the heart. In this condition, the contractions of the atria and ventricles are uncoordinated. If not addressed promptly, the condition can lead to heart failure and sudden death.

In the United States, approximately 300,000 individuals are diagnosed with ventricular fibrillation. The condition is more common in men than women. Individuals of African American descent are also at a higher risk for ventricular fibrillation. The condition rarely occurs in infants under the age of 6 months and in adults ages 45 to 75 years old.

Causes and risk factors

The main cause of ventricular fibrillation is myocardial infarction, but the condition can result from other cardiovascular comorbid conditions and/or when the heart does not get enough oxygen. Other conditions that can lead to ventricular fibrillation include congenital heart disease, coronary artery disease, shock, electrical shock, drowning, very low levels of potassium, electrocution accidents, injury to heart, cardiomyopathies, congestive heart failure, heart surgery, administration of drugs that affect electrical currents such as sodium blockers, and/or ischemia.

Additional risk factors include family history of cardiovascular disease, medical history of cardiovascular conditions, hypertension, high cholesterol, diabetes, smoking, and/or alcohol or illicit drug abuse.

Symptoms

Ventricular fibrillation is a serious condition that, if not attended to promptly, may result in sudden death or congestive heart failure. The symptoms associated with the condition can resemble that of other cardiovascular conditions and can vary from patient to patient. Individuals with an acute ventricular fibrillation episode typically present by fainting or suddenly collapsing and/or becoming unconscious. They also typically present with very rapid or undetectable heart rate.

Symptoms that typically occur before an individual having an acute ventricular fibrillation episode faints or becomes unconscious include chest pain, seizures, dizziness, nausea, vomiting, rapid heartbeat, shortness of breath, confusion, and weakness.

Diagnosis and screening

Ventricular fibrillation is an emergency condition that requires immediate attention to prevent serious complications such as congestive heart failure and sudden death. Physical examination, medical history, and diagnostic tools are used to screen for ventricular fibrillation. Upon physical examination, practicing clinicians will look for rapid or irregular heart rate of, hypertension, or hypotension. The patient may also present with a very low or no heart rate and a cardiac monitor will demonstrate a disorganized heart rate.

Diagnostic screening tests used to confirm diagnosis of ventricular fibrillation include electrocardiogram, cardiac monitor, Holter monitor, and event recorder
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Ventricular tachycardia

Ventricular tachycardia is a condition that is initiated in the ventricle and results in a very rapid or irregular heartbeat. The condition is triggered by 3 or more consecutive premature ventricular heartbeats. Ventricular tachycardia can result in heartbeats ranging from 160 to 240 beats per minute. The condition can be classified as nonsustained or sustained.

In the United States, ventricular tachycardia occurs in approximately 2 out of 10,000 individuals. The incidence of ventricular tachycardia in the United States remains unknown due to overlap with ventricular fibrillation. Ventricular tachycardia is more prevalent among men than women, but varies with the risk factors for atherosclerosis. The incidence of ventricular tachycardia increases with natural aging and with prevalence of coronary artery disease.

Causes and risk factors

The most common cause of ventricular tachycardia is the presence of coronary artery disease. Ventricular tachycardia can result from the presence of other comorbid cardiovascular conditions or in the absence of any other cardiac diseases. It can also occur as a result of myocardial infarction, congestive heart failure, cardiomyopathy, cardiac valvular disease, myocarditis, ischemia, electrolyte abnormalities, high potassium levels, high magnesium levels, adrenergic stimulation, and post–cardiovascular surgery.

Additional risk factors include family history of cardiovascular disease, medical history of cardiovascular conditions, hypertension, high cholesterol, diabetes, smoking, and/or alcohol or illicit drug abuse.

Symptoms

The symptoms of ventricular tachycardia can vary depending on the degree and extent of disease. Some patients present with severe symptoms that require emergency treatment. However, other patients may present with few or no symptoms, which may or may not require medical intervention. In addition, symptoms may start and stop suddenly. Ventricular tachycardia is most commonly associated with coronary artery disease and can present with a nonsustained or sustained rapid heart rate.

The most common symptoms individuals with ventricular tachycardia present with include heart palpitations, rapid heartbeat, lightheadedness, dizziness, confusion, weakness, fatigue, fainting, shortness of breath, and chest discomfort.

Diagnosis and screening

Physical examination, medical history, and diagnostic tools are used to diagnose ventricular tachycardia. Upon physical examination, practicing clinicians will look for rapid or irregular heart rate and changes in blood pressure. The patient may also present with a very low or no heart rate and normal or low blood pressure. Individuals with ventricular tachycardia may present with fainting or in an unconscious state.

Diagnostic tools used to screen for ventricular tachycardia and assess for causes include electrocardiogram, echocardiogram, Holter monitor, intracardiac electrophysiology studies, event recorder, chest x-ray, magnetic resonance imaging, and thyroid function tests. Also, blood work may be completed to access other contributing factors including thyroid function tests, electrolyte levels, and metabolic function tests.

Intermittent claudication

Intermittent claudication is a condition that arises from peripheral arterial disease. Approximately one-third to one-half of individuals diagnosed with peripheral arterial disease present with intermittent claudication. The condition occurs after physical exertion and consists of pain during physical activity, which resolves once the activity is stopped. The pain most commonly occurs in the calves, thighs, and/or buttocks.

The condition is defined as muscle pain or cramping in appendages triggered by walking and physical activity. Individuals may also experience ischemic rest pain. The condition results from inadequate oxygen supply to the legs because of impeded blood flow.

Intermittent claudication occurs more commonly in men than women. It also occurs more often in individuals with a history of smoking, cardiovascular comorbid conditions, diabetes, and high blood pressure. The estimated prevalence of intermittent claudication is approximately 4.5 million individuals. It has been estimated that 60% to 70% of individuals with intermittent claudication have persistent symptoms, 20% to 25% symptoms get worse, and 10% require surgical intervention. The rate of amputation is approximately 1% to 2% per year.

Causes and risk factors

Intermittent claudication is most commonly associated with peripheral arterial disease. Both genetic and environmental factors can contribute to the onset of intermittent claudication.

The risk factors and causes for intermittent claudication are very similar to peripheral arterial disease as the former is a symptom of the latter. Conditions that can lead to intermittent claudication include blood clots, injury to limbs, and unusual anatomy of ligaments or muscles or infection. 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 and intermittent claudication include smoking, 50 years of age or older, diabetes, obesity, high blood pressure, high cholesterol or family history of cardiovascular diseases and/or arthrosclerosis. 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 and intermittent claudication.

Symptoms

The main symptoms of intermittent claudication include pain in a functional muscle group located in the legs such as calf, buttock, and thigh, pain after strenuous activity such as brisk walking or physical activity, and reduction of pain once physical activity is stopped.

The symptoms of intermittent claudication are associated with other symptoms of peripheral arterial disease including 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.

Diagnosis and screening

The symptoms of individuals with intermittent claudication may vary. Therefore, practicing clinicians should assess the patient’s medical history, presence of comorbid conditions and examine the patient. Physical examination, medical history, and diagnostic screening tools are used to determine if a patient has intermittent claudication.

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, muscle pain or cramping upon physical activity, temperature changes and decreased blood pressure in limbs. Diagnostic screening tools include the ankle-brachial index and angiography. Additional tests include electrocardiogram, magnetic resonance angiography, blood tests, and ultrasound.

Hypotension

Hypotension is defined as low pressure, particularly lower than 90/60 mmHg. However, what practicing clinicians consider low blood pressure varies from patient to patient because some individuals have naturally low blood pressure with no symptoms. Also, patients with comorbid conditions like hepatic disease (cirrhosis) may have lower than normal blood pressure at baseline.

Drops in blood pressure of more than 20 mmHg are more of a concern from a patient’s normal blood pressure, as it can cause symptoms of dizziness, fainting and decreased mental capacity. It can also be an indicator of a more serious underlying condition such as uncontrolled bleeding, severe infections, and/or allergic reactions

Orthostatic hypotension
or postural hypotension is defined as low blood pressure upon standing. In this condition, an individual’s blood pressure drops when going from a sitting to standing position, leading to dizziness, lightheadedness, blurred vision, and fainting or syncope. The causes of orthostatic hypotension include dehydration, prolonged bed rest, pregnancy, diabetes, heart problems, burns, excessive heat exposure, large varicose veins, and certain neurological disorders. Drugs that can lead to orthostatic hypotension include diuretics, beta-blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, and antidepressants.

The condition is more common in older individuals, with 20% of cases occurring in individuals aged 65 or older.

Postprandial hypotension
is a condition that involves a sudden drop in blood pressure after eating. It typically affects elderly individuals with other cardiovascular comorbid condition or neurological disorders. Symptoms of the condition include dizziness, fatigue, syncope or fainting, mental confusion, and/or lightheadedness. Postprandial hypotension is more common among individuals with high blood pressure or autonomic nervous system disorders. Lifestyle modifications such as eating smaller meals low in carbohydrates more often may reduce symptoms. Also, lowering the dose of blood pressure medications may decrease the onset of postprandial hypotension.

Shy-Drager syndrome
, also known as multiple system atrophy with orthostatic hypotension, is a rare disease that causes progressive damage to the autonomic nervous system. Deterioration of the autonomic nervous system leads to improper functioning of blood pressure, heart rate, breathing, and digestion. The main characteristic of Shy-Drager syndrome is severe hypotension when standing and severe hypertension when lying down. Other symptoms of the disease include muscle tremors, slowed movement, problems with coordination and speech, and incontinence. The disease is progressive, with few treatment approaches, and usually leads to death within 7 to 10 years from time of diagnosis.