Ch 27: Disorder of Cardiac Function

Typically, chronic stable angina is provoked by _____ or _____ stress and relieved within minutes by rest or the use of nitroglycerin.

exertion, emotional

Mitral valve _____ represents the incomplete opening of the mitral valve during diastole with left atrial distention and impaired filling of the left ventricle.

stenosis

Left ventricular dysfunction in response to profound psychological or emotional stress

stress cardimyopathy

The _____ have high specificity for myocardial tissue and have become the primary biomarker for the diagnosis of myocardial infarction

troponin assays

chest pain occurring while at rest

unstable angina

The gastrointestinal symptoms of ST-segment elevation myocardial infarction are believed to be related to the severity of the pain and _____ stimulation.

vagal

Infarcted and noninfarcted areas of the heart muscle in patients with ST-segment elevation myocardial infarction can change size, shape, and thickness, a term referred to as ____

ventricular remodeling

Irreversible myocardial cell death occurs after _____ minutes of severe ischemia.

20 to 40

Aortic _____ is the result of an incompetent aortic valve that allows blood to flow back to the left ventricle during diastole.

regurgitation

Mitral valve prolapse occurs frequently in the population at large. Its treatment is aimed at relieving symptoms and preventing complications of the disorder. Which drug is used in the treatment of mitral valve prolapse to relieve symptoms and aid in preventing complications? a. Beta-adrenergic blocking drugs b. Calcium channel-blocking drugs c. Antianxiety drugs d. Broad-spectrum antibiotic drugs

a. Beta-adrenergic blocking drugs RATIONALE: Persons with palpitations and mild tachyarrhythmias or increased adrenergic symptoms, as well as those with chest discomfort, anxiety, and fatigue, often respond to therapy with the 13-adrenergic blocking drugs.

When an acute myocardial infarction (Ml) occurs, many physiologic changes occur very rapidly. What causes the loss of contractile function of the heart within seconds of the onset of an MI? a. Conversion from aerobic to anaerobic metabolism b. Overproduction of energy capable of sustaining normal myocardial function c. Conversion from anaerobic to aerobic metabolism d. Inadequate production of glycogen with mitochondrial shrinkage

a. Conversion from aerobic to anaerobic metabolism RATIONALE: The principal biochemical consequence of MI is the conversion from aerobic to anaerobic metabolism with inadequate production of energy to sustain normal myocardial function. As a result, a striking loss of contractile function occurs within 60 seconds of onset.

Nearly everyone with pericarditis has chest pain. With acute pericarditis, the pain is abrupt in onset and sharp, and radiates to the neck, back, abdomen, or sides. What can be done to ease the pain of acute pericarditis? a. Have patient sit up and lean forward b. Have patient change positions to unaffected side c. Have patient breathe deeply d. Have patient swallow slowly and frequently

a. Have patient sit up and lean forward RATIONALE: The pain is typically worse with deep breathing, coughing, swallowing, and positional changes because of changes in venous return and cardiac filling. All other answers make the pain worse.

The diagnosis of chronic stable angina is based on a detailed pain history, the presence of risk factors, invasive and noninvasive studies, and laboratory studies. What test is not used in the diagnosis of angina? a. Serum biochemical markers b. Cardiac catheterization c. Echocardiogram d. Nuclear imaging studies

a. Serum biochemical markers RATIONALE: Serum biochemical markers for myocardial infarction are normal in patients with chronic stable angina.

Unstable plaque, a condition of atherosclerotic heart disease, occurs in unstable angina and myocardial infarction. Unstable plaque can rupture, causing platelet aggregation and thrombus formation. What are the major determinants of the vulnerability of plaque to rupture? Mark all that apply. a. Size of lipid-rich core b. Preponderance of smooth muscle cells c. Presence of inflammation d. Decrease in blood pressure and coronary blood flow e. Thickness of fibrous cap

a. Size of lipid-rich core c. presence of inflammation e. thickness of fibrous cap RATIONALE: The major determinants of plaque vulnerability to disruption include the size of the lipid-rich core, the stability and thickness of its fibrous cap, the presence of inflammation, and the lack of smooth muscle cells.

_____ myocardial infarction is characterized by the ischemic death of myocardial tissue associated with atherosclerotic disease of the coronary arteries.

acute ST-segment

Heart muscle disease that affects primarily the right ventricle

arrhythmogenic right ventricular cardiomyopathy

ST-elevated myocardial infarction (STEMI) is accompanied by severe, crushing pain. Morphine is the drug of choice used to treat the pain of STEMI when the pain cannot be relieved with oxygen and nitrates. Why is morphine considered the drug of choice in STEMI? a. Action increases autonomic nervous system activity b. Action decreases metabolic demands of the heart c. Action increases anxiety, thus increasing metabolic demands of heart d. Action relieves pain and gives sense of depression

b. Action decreases metabolic demands of heart RATIONALE: Although a number of analgesic agents have been used to treat the pain of STEMI, morphine is usually the drug of choice. It is indicated if chest pain is unrelieved with oxygen and nitrates.

Heart failure in an infant usually manifests itself as tachypnea or dyspnea, both at rest and on exertion. When does this most commonly occur with an infant? a. During bathing b. During feeding c. During burping d. During sleep

b. During feeding RATIONALE: Heart failure manifests itself as tachypnea or dyspnea at rest or on exertion. For the infant, this most commonly occurs during feeding.

Cardiac tamponade is a serious lifethreatening condition that can arise from a number of other conditions. What is a key diagnostic finding in cardiac tamponade? a. Increase in stroke volume b. Pulsus paradoxus c. Narrowed pulse pressure d. Rise in systolic blood pressure

b. Pulsus paradoxus RATIONALE: A key diagnostic finding is pulsus paradoxus, or an exaggeration of the normal variation in the systemic arterial pulse volume with respiration. None of the other answers occur in cardiac tamponade.

Tetralogy of Fallot is a congenital condition of the heart that manifests in four distinct anomalies of the infant heart. It is considered a cyanotic heart defect due to the right-to-left shunting of the blood through the ventricular septal defect. A hallmark of this condition is the "tet spells" that occur in these children. What is a tet spell? a. A stressful period right after birth that occurs without evidence of cyanosis b. A hyperoxygenated period when the infant is at rest c. A hypercyanotic attack brought on by periods of stress d. A hyperpneic attack in which the infant loses consciousness

c. Hypercyanotic attack brought on by periods of stress RATIONALE: The degree of obstruction may be dynamic and can increase during periods of stress, causing hypercyanotic attacks ("tet spells").

The scar tissue that occurs between the layers of the pericardium becomes rigid and constrictive from scar tissue in constrictive pericarditis. What is a physiologic sign of constrictive pericarditis? a. Kussmaul breathing b. Pulsus paradoxus c. Kussmaul sign d. Widening pulse pressure

c. Kussmaul sign RATIONALE: Kussmaul sign is an inspiratory distention of the jugular veins caused by the inability of the right atrium, encased in its rigid pericardium, to accommodate the increase in venous return that occurs with inspiration. None of the other physiologic signs occur in constrictive pericarditis.

In infective endocarditis, vegetative lesions grow on the valves of the heart. These vegetative lesions consist of a collection of infectious organisms and cellular debris enmeshed in the fibrin strands of clotted blood. What are the possible systemic effects of these vegetative lesions? a. They can block the heart valves from closing completely. b. They can keep the heart valves from opening. c. They can fragment and cause cerebral emboli. d. They can fragment and make the lesions larger.

c. They can fragment & cause cerebral emboli. RATIONALE: The intracardiac vegetative lesions also have local and distant systemic effects. The loose organization of these lesions permits the organisms and fragments of the lesions to form emboli and travel in the bloodstream, causing cerebral, systemic, or pulmonary emboli.

mechanical compression of heart

cardiac tamponade

_____ cardiomyopathies are characterized by atrophic and hypertrophic myocardial fibers and interstitial fibrosis.

dilated

Ventricular enlargement, a reduction in ventricular wall thickness, and impaired systolic function

dilated cardiomyopathy

invasion of heart valves & mural endocardium by microbial agent

infective endocarditis

Conduction disorders in the heart resulting from abnormal membrane potentials (long QT /short QT syndromes)

ion channelopathies

decreased blood flow to tissue

ischemia

Failure of trabecular compaction in the developing myocardium

left ventricular noncompaction

Myocardial blood flow, in turn, is largely regulated by the _____ of the myocardium and _____ mechanisms that control vessel dilation.

metabolic activity, autoregulatory

The _____ cardiomyopathies, which include dilated cardiomyopathy, are of both genetic and nongenetic origin.

mixed

An inflammation of the heart

myocarditis

The _____ manifestation of rheumatic fever is Sydenham chorea, where the child often is fidgety, cries easily, begins to walk clumsily, and drops things.

neurologic

Partial or complete rupture of a(n) _____ is a rare but often fatal complication of transmural myocardial infarction.

papillary muscle

accumulation of fluid in pericardial cavity

pericardial effusion

Occurs during the last trimester of pregnancy or the first 6 months after delivery

peripartum cardiomyopathy

________ is the most common and, frequently, the first manifestation of rheumatic fever.

polyarthritis

chest pain due to coronary artery spasm

prinzmetal angina

Most persons with mitral valve ____ _ are asymptomatic, and the disorder is discovered during a routine physical examination.

prolapse

exaggeration of normal variation in pulse during inspiratory phase of respiration

pulsus paradoxus

Mitral valve _____ is characterized by incomplete closure of the mitral valve, with the left ventricular stroke volume being divided between the forward stroke volume that moves into the aorta and the regurgitant stroke volume that moves back into the left atrium during systole.

regurgitation

ventricular filling restricted because of excessive rigidity of ventricular walls

restrictive cardiomyopathy

Heart muscle disease in the presence of a multisystem disorder

secondary cardiomyopathy

occurs in absence of anginal pain

silent myocardial ischemia

combination of effusion-tamponade & constriction

effusive-constrictive pericarditis

It is known that more than 100 distinct myocardial diseases can demonstrate clinical feattues associated with dilated cardiomyopathy (DCM). What is the most common identifiable cause of DCM in the United States? a. Hepatic cardiomyopathy b. Alcoholic cardiomyopathy c. Cardiotoxic cardiomyopathy d. Exercise-induced cardiomyopathy

b. Alcoholic cardiomyopathy RATIONALE: Alcoholic cardiomyopathy is the single most common identifiable cause of DCM in the United States and Europe.

Unstable angina/non-ST-segment elevation myocardial infarction is a clinical syndrome that ranges in severity between stable angina to myocardial infarction (Ml). It is classified according to its risk of causing an acute MI and is diagnosed based on what? Mark all that apply. a. Severity of pain and abruptness of onset b. Serum biomarkers c. Coexisting chronic conditions d. ECG pattern e. Blood flow angiography

b. Serum biomarkers d. ECG pattern RATIONALE: Unstable angina (UA)/non-ST-segment elevation myocardial infarction (NSTEMI) is classified as either low or intermediate risk of acute MI, the diagnosis of which is based on the clinical history, ECG pattern, and serum biomarkers.

Increased resistance to ejection of blood from the left ventricle into the aorta characterizes aortic valve _____ _

stenosis

During an acute myocardial infarction (Ml), there is ischemic damage to the heart muscle. The location and extent of the ischemic damage is the major predictor of complications, ranging from cardiac insufficiency to death, following an ML What is the "window of opportunity" in restoring blood flow to the affected area so as to diminish the ischemic damage to the heart and maintain the viability of the cells? a. 10 to 20 minutes b. 30 to 40 minutes c. 20 to 40 minutes d. 10 to 30 minutes

c. 20 to 40 minutes RATIONALE: If blood flow can be restored within the 20- to 40-minute time frame, loss of cell viability does not occur or is minimal.

Angina pectoris is a chronic ischemic coronary artery disease that is characterized by a symptomatic paroxysmal chest pain or pressure sensation associated with transient myocardial ischemia. What precipitates an attack of angina pectoris? a. Exposure to heat b. Sedentary lifestyle c. Abrupt change in position d. Emotional stress

d. Emotional stress RATIONALE: Angina pectoris is usually precipitated by situations that increase the work demands of the heart, such as physical exertion, exposure to cold, and emotional stress. The pain is typically described as a constricting, squeezing, or suffocating sensation.

Antibodies directed against the M protein of certain strains of streptococcal bacteria seem to cross-react with glycoprotein antigens in the heart, joint, and other tissues to produce an autoimmune response resulting in rheumatic fever and rheumatic heart disease. This occurs through what phenomenon? a. Aschoff reaction b. Sydenham reaction c. C-reactive mimicry d. Molecular mimicry

d. Molecular mimicry RATIONALE: It is believed that antibodies directed against the M protein of certain strains of streptococci cross-react with glycoprotein antigens in the heart, joint, and other tissues to produce an autoimmune response through a phenomenon called molecular mimicry.

A patient with a suspected myocardial infarction (Ml) is brought to the emergency department by ambulance. As the nurse caring for this patient, what lab work would you expect to receive an order for to confirm a diagnosis of MI? a. Creatine kinase marker b. Complete blood components c. Calcium level d. Troponin level

d. Troponin level RATIONALE: The troponin assays have high specificity for myocardial tissue and have become the primary biomarker for the diagnosis of myocardial infarction (MI). The troponin complex, which is part of the actin filament, consists of three subunits (i.e., TnC, TnT, Tnl) that regulate calcium-mediated actin-myosin contractile process in striated muscle.

The _____ cardiomyopathies include hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, left ventricular noncompaction cardiomyopathy, inherited conduction system disorders, and ion channelopathies.

genetic

ST-segment elevation myocardial infarction

heart attack

Disproportionate thickening of the ventricular septum and left ventricle

hypertrophic cardiomyopathy