Understanding Valvular Heart Disorders: Regurgitation & Stenosis, Summaries of Medicine

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S. Sheppard,

Management of patients

with structural infectious

and inflammatory cardiac

disorders

Chapter 28 Management of Patients with Structural, Infectious, and Inflammatory Cardiac Disorders Valvular Disorders

• Tricuspid valve : separates the right atrium from the right ventricle
• Mitral valve: separates the left atrium from the left ventricle
• Semilunar valves located between the ventricles and their corresponding arteries o Pulmonic valve: lies between the right ventricle and the aorta o Aortic valve: lies between the left ventricle and the aorta
• Regurgitation: The valve does not close properly, and blood backflows through the valve
• Stenosis: The valve does not open completely, and blood flow through the valve is reduced
• Valve prolapse: The stretching of an atrioventricular valve leaflet into the atrium during diastole
• Patients may not require treatment, or they may need to make lifestyle changes, take medications, or require surgical repair or replacement of valve.
• Regurgitation and stenosis may occur at the same time in the same or different valves. Mitral Prolapse
• A deformity that usually produces no symptoms
• Rarely, it progresses and can result in sudden death.
• The cause may be inherited connective tissue disorder resulting in enlargement of one or both mitral leaflet
• A portion of one or both mitral valve leaflets balloons back into the atrium during systole.
• About 15% of patients who develop murmurs eventually experience heart enlargement, A fib, pulmonary hypertension, or HF.
• Clinical Manifestations o Most people don’t have symptoms o A few have fatigue, SOB, lightheadedness, dizziness, syncope, palpitations, chest pain or anxiety o Fatigue may occur regardless of activity level and amount of rest or sleep. o SOB is not correlated with activity levels or pulmonary function o Atrial or ventricular dysrhythmias may produce the sensation of palpitations o Pain is not correlated with activity and may last for days o Some symptoms may be explained by dysautonomia (a dysfunction of the autonomic nervous system that results in increased excretion of catecholamines)
• Assessment and Diagnostic Findings o First and only sign of mitral valve prolapse is an extra heart sound (mitral click) o A systolic click is an early sign that a valve leaflet is ballooning into the left atrium o A murmur of mitral regurgitation may be heard if the valve opens during systole and blood flows back into the left atrium o Pt may experience symptoms of HF if mitral regurgitation occurs

• The right ventricle also hypertrophies, eventually dilate, and fails.
• The heart rate increases, cardiac output decreases and pulmonary pressures increase
• most often caused by rheumatic endocarditis, which thickens mitral valve leaflets and chordae
• leaflets often fuse together
• Clinical Manifestations o First symptom of mitral stenosis is often dyspnea on exertion as a result of pulmonary venous hypertension o Patients may experience fatigue and decreased exercise tolerance o An enlarged left atrium may create pressure on the left bronchial tree, resulting in a dry cough or wheezing. o Pt may expectorate blood (hemoptysis) or experience palpitations, orthopnea, paroxysmal nocturnal dyspnea (PND), and repeated respiratory infections o As a result of increased blood volume and pressure, the atrium dilates, and becomes electrically unstable (pt experience atrial dysrhythmias.
• Prevention o Minimize risk and treat bacterial infections o Prevention of acute rhematic fever depends on effective antibiotic treatment of group A streptococcal infection o Antibiotic prophylaxis for recurrent rheumatic fever with rheumatic carditis may requires 10 or more years of antibiotic coverage (Penicillin G IM every 4 weeks, penicillin V PO BID, sulfadiazine PO daily, or erythromycin PO BID)
• Medical Management o Anticoagulants are used to decrease the risk of developing atrial thrombus and may require treatment for angina o If atrial fibrillation develops, cardioversion is attempted to restore normal sinus rhythm. o If unsuccessful, the ventricular rate is controlled with beta-blockers, digoxin, or calcium channel blockers o Avoid strenuous activities, competitive sports and pregnancy o Surgical intervention consists of valvuloplasty to open or rupture the fused commissures of the valve Aortic Regurgitation
• The flow of blood back into the left ventricle from the aorta during diastole
• may be caused by inflammatory lesions that deform aortic valve leaflets or dilation of the aorta, preventing complete closure of the aortic valve
• this defect also may result from ineffective rheumatic endocarditis, congenital abnormalities, diseases such as syphilis, a dissecting aneurysm, blunt chest trauma, or deterioration of a surgically replaced aortic valve
• Clinical manifestations o Aortic insufficiency develops without symptoms in most patients o Marked arterial pulsations visible or palpable at carotid or temporal arteries may be present as a result of increased force in volume of blood ejected from a hypertrophied left ventricle o Dyspnea on exertion, orthopnea, PND

• Assessment o High-pitched blowing diastolic murmur is heard at the 3 rd^ or 4 th^ intercostal space of the left sternal border o Pulse pressure (difference btwn systolic and diastolic pressures) is widened o Characteristic sign is the water hammer (Corrigan’s) pulse, the pulse strikes a palpating finger with a quick, sharp stole and then suddenly collapses o Diagnoses confirmed by echocardiography (preferably transesophageal), cardiac magnetic resonance imaging (MRI), cardiac cath.
• Medical Management o Symptomatic patient or patient with decreased left ventricular function, is advised to avoid physical exertion o Should be treated with dihydropyridine calcium channel blockers (felodipine, nifedipine) or ACE inhibitors (captopril, enalapril, lisinopril, ramipril) to provides afterload reduction o Restrict sodium and avoid fluid overload Aortic Stenosis
• Narrowing of the orifice between the left ventricle and aorta
• In adults, stenosis is a result of degenerative calcifications that may be caused by proliferative and inflammatory changes that occur from normal mechanical stress.
• Age, diabetes, hypercholesterolemia, hypertension, smoking, and elevated levels of LDL cholesterol may be factors for degenerative calcific changes of the valve
• Clinical Manifestations o Asymptomatic response if stenosis develops slowly – left ventricle compensates o Exertional dyspnea, orthopnea, PND, pulmonary edema, dizziness and syncope (decreased blood flow to brain), angina o BP may be normal or low. Pulse pressure may be low because of diminished blood flow
• Assessment and Diagnostic findings o A loud, harsh systolic murmur may be heard over the aortic area (Right second intercostal space) and may radiate to the carotid arteries and the apex of the left ventricle o The murmur is low pitched, crescendo-decrescendo, rough rasping, and vibrating o S4 sound may be heard o Echocardiography, cardiac MRI, and CT scanning are used to diagnose and monitor
• Medical Management o Surgical intervention (valve replacement, balloon valvuloplasty Nursing Management: Valvular Heart Disorders
• Patient education
• Monitor VS trends
• Monitor for complications o Heart failure o Dysrhythmias

▪ Bleeding, thromboembolism, infection, heart failure, hypertension, dysrhythmias, hemolysis and mechanical obstruction of the valve o Mechanical valves: thought to be more durable than tissue prosthetic valves. ▪ Used for patients with kidney injury, hypercalcemia, endocarditis or sepsis ▪ Complications: thromboemoli and long-term anticoagulation therapy required o Tissue valves: less likely to generate thromboembolic and long-term anticoagulation is not required o Bioprosthesis are tissue valves (heterographs) used for aortic, mitral, and tricuspid valve replacement. ▪ Long-term anticoagulation not required ▪ Used for women of child-bearing age because potential complications of long-term anticoagulation associated with menses, placental transfer to a fetus and delivery of a child are avoided ▪ Most bioprostheses are from pigs (porcine), some from cows (bovine) or horses (equine) ▪ Viability is 7 to 15 yrs o Homografts or allografts (human valves) are obtained from a cadaver tissue donation and used for aortic and pulmonic valve replacement o Autografts (autologous valves) obtained by excising the patient’s own pulmonic valve and a portion of the pulmonary artery for use as the aortic valve ▪ Anticoagulation is unnecessary ▪ It is an alternative for children, women of childbearing age, young adults, pt with history of peptic ulcer disease, and people who cannot tolerate anticoagulation. Nursing Management: Valvuloplasty and Valve Replacement

• Balloon Valvuloplasty o Monitor for heart failure and emboli o Assess heart sounds q4h o Same care as after cardiac catheterization
• Surgical valvuloplasty or valve replacements o Focus is hemodynamic stability and recovery from anesthesia o Frequent assessments with attention to neurologic, respiratory, and cardiovascular systems
• Patient education o Anticoagulation therapy o Prevention of infective endocarditis o Follow up o Repeat echocardiograms

Cardiomyopathy

• Cardiomyopathy is a series of progressive events that culminates in impaired cardiac output and can lead to heart failure, sudden death, or dysrhythmias.
• Types o Dilated cardiomyopathy (DCM) ▪ Most common cardiomyopathy ▪ Dilation of ventricles without hypertrophy ▪ Elevated volume, decreased ejection fraction ▪ Yields high end-diastolic pressure – higher pulmonary and systemic venous pressure o Hypertrophic cardiomyopathy (HCM) ▪ autosomal dominant condition ▪ family history of HCM critical factor ▪ ongoing monitoring of echocardiograms ▪ Increased risk of dysrhythmias (VT, VF) ▪ Restrict blood to myocardium o Restrictive/constrictive cardiomyopathy (RCM) ▪ Predominant diastolic dysfunction ▪ Dyspnea, nonproductive cough, chest pain, echocardiography, arterial and venous pressure measurements o Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) o Unclassified cardiomyopathy
• Clinical manifestations o Patients may remain stable and without symptoms for many years. o Dilated and restrictive cardiomyopathy is first diagnosed when the patient presents with s&s of heart failure (DOE, fatigue) o May report PND, cough, orthopnea o Fluid retention, peripheral edema, and nausea o Chest pain, palpitations, dizziness, nausea and syncope on exertion
• Nursing Process: Nursing diagnoses o Decreased cardiac output o Risk for ineffective cardiac, cerebral, peripheral, and renal tissue perfusion o Impaired gas exchange o Activity intolerance o Anxiety o Powerlessness o Noncompliance with medication and diet therapies
• Collaborative Problems and potential complications o Heart failure o Ventricular dysrhythmias o Atrial dysrhythmias o Cardiac conduction defects o Pulmonary or cerebral embolism o Valvular dysfunction
• Nursing Process: Planning and Goals

Infectious Diseases of the Heart

• Any of the layers of the heart may be affected by an infectious process
• Infections are named by the layer of the heart that is affected
• Diagnosis is made by patient symptoms and echocardiogram
• Management of all infectious diseases is prevention
• IV antibiotics usually are necessary once an infection has developed in the heart
• Rheumatic endocarditis o Occurs most often in school-age children after group A beta-hemolytic streptococcal pharyngitis; need to promptly recognize and treat “strep” throat to prevent rheumatic fever
• Infective endocarditis o Usually develops in people with prosthetic heart valves or structural cardiac defects; also occurs in patients who are IV drug abusers and in those with debilitating diseases, indwelling catheters, or prolonged IV therapy o Clinical manifestations ▪ Primary symptoms are fever and heart murmur ▪ Clusters of petechiae may be found on the body ▪ Small, painful nodules (Osler nodes) may be present in pads of fingers and toes ▪ Irregular, red or purple, painless flat macules (Janeway lesions) may be present on palms, fingers, hands, soles, and toes ▪ Hemorrhages with pale centers (Roth spots) caused by emboli may be observed in the fundi of the eyes. ▪
• Pericarditis o Inflammation of the pericardium; many causes; potential complications: pericardial effusion and cardiac tamponade o Pain or discomfort usually remains fairly constant, but it may worsen with deep inspiration and when lying down or turning. o Medical management ▪ Impaired cardiac output = bed rest ▪ NSAIDs such as aspirin and ibuprofen are prescribed for pain ▪ Colchicine or corticosteroids (prednisone) for severe pericarditis
• Myocarditis o An inflammatory process involving the myocardium; most common pathogens involved in myocarditis tend to be viral; in endocarditis, they tend to be bacterial; complications: cardiomyopathy and heart failure ▪ Medical management - Treat underlying cause if it is known (penicillin for hemolytic streptococci) and - Placed on bed rest to decrease cardiac workload - In young patients, activities should be limited for a 6 - month period or until heart has returned to normal size - Physical activity is slowly increased, advised to report any symptoms with activity

• NSAIDS should not be used, could make it worse!
• Clinical manifestations o Fever o New heart murmur, friction rub at left lower sternal border, chest pain (pericarditis) o Osler nodes, Janeway lesions, Roth spots, and splinter hemorrhages in nailbeds (rheumatic) o Cardiomegaly, heart failure, tachycardia, splenomegaly (endocarditis) o Fatigue, dyspnea, syncope, palpitations, chest pain (myocarditis) o Diagnostic tools : blood cultures, echocardiogram, CBC, rheumatoid factor, ESR, CRP, urinalysis, ECG, cardiac catheterization, CMR imaging, TEE, CT scan
• Prevention o Antibiotic prophylaxis before certain procedures o Ongoing oral hygiene o Female patients are advised NOT to use IUDs o Meticulous care should be taken in patients “at risk” who have catheters o Catheters should be removed as soon as they are no longer needed o Immunizations