The myocardium becomes rigid and noncompliant, impeding ventricular filling and raising filling pressures during diastole.
Structural alterations of the heart valves lead to stenosis, incompetence, or both.
Hypertrophy of the myocytes is an attempt to compensate for increased myocardial workload.
A thorough evaluation for the underlying cause should be initiated and may include myocardial biopsy.
The prognosis is poor.
Valvular disease is generally diagnosed by echocardiography.
Symptoms of decreased cardiac output, especially during exertion.
By chest x-rays and electrocardiography.
Symptomatic mitral valve prolapse can cause palpitations related to dysrhythmias, tachycardia, lightheadedness, syncope, fatigue (especially in the morning), lethargy, weakness, dyspnea, chest tightness, hyperventilation, anxiety, depression, panic attacks, and atypical chest pain.
Untreated aortic stenosis can lead to dysrhythmias, myocardial infarction, and heart failure.
At the time cardiac or joint symptoms begin to appear.
Resistance to flow through the stenotic valve gives rise to a crescendo-decrescendo systolic heart murmur in aortic stenosis.
Appropriate antibiotic therapy given within the first 9 days of infection usually prevents rheumatic fever.
Both skin infections and pharyngeal infections can cause acute glomerulonephritis.
Because they are embedded in protective fibrin clots.
The severity of regurgitation can be estimated by echocardiography.
Repeated attacks of acute rheumatic fever cause chronic proliferative changes in organs due to scarring, granulomas, and thromboses.
Surgical repair or valve replacement may become necessary when the severity of regurgitation is estimated by echocardiography.
The most common clinical manifestation is right heart failure with systemic venous congestion.
The left heart valves (mitral and aortic semilunar valves) are more commonly affected than the right heart valves (tricuspid and pulmonic semilunar valves).
It leads to inflammation and scarring of the valvular leaflets.
The three common causes of aortic stenosis are congenital bicuspid valve, calcific degeneration related to aging, and inflammatory damage caused by rheumatic heart disease.
Degenerative aortic stenosis is linked to hyperlipidemia.
Left ventricular hypertrophy develops to compensate for the increased workload in aortic stenosis.
Severe sequelae such as chordae rupture, ventricular failure, systemic emboli, and sudden death are possible with mitral valve prolapse.
A decrescendo murmur.
Eradicating the streptococcal infection using a 10-day regimen of antibiotics.
Acute rheumatic fever occurs most often in children between 5 and 15 years of age.
Streptococcal skin infections do not progress to acute rheumatic fever because the strains of the microorganism that infect the skin do not have the same antigenic molecules in their cell membranes as those that cause pharyngitis and therefore do not elicit the same kind of immune response.
The endothelial basement membrane, which contains a type of collagen that attracts platelets and stimulates sterile thrombus formation.
On heart valves and surrounding structures.
Echocardiography and cardiac catheterization can confirm the diagnosis.
Endocardial damage can be either congenital or acquired.
Valvular regurgitation increases the volume of blood the heart must pump and increases the workload of the affected heart chamber.
Incomplete emptying of the left atrium and elevated atrial pressure.
29% of adults in the United States have degenerative sclerotic aortic valves.
The orifice of the aortic semilunar valve narrows in aortic stenosis.
Several antibody tests, including antideoxyribonucleotidase (anti-DNase B), antihyaluronidase, and antistreptozyme (ASTZ).
If regurgitation is present, medical treatment includes afterload reduction, diuresis, anticoagulation for associated atrial fibrillation, and other medications for heart failure.
Echocardiography is used to follow aortic stenosis.
Recurrence rates decline with the length of time elapsed since the last infection.
Morbidity and mortality diminished significantly with the advent of antibiotics and improved diagnostic techniques.
The chronic sequelae of rheumatic fever result from progressive fibrosis due to healing of the inflammatory lesions and the changes induced by valvular deformities.
Abscesses and characteristic skin changes such as petechiae, splinter hemorrhages, Osler nodes, and Janeway lesions.
Mitral regurgitation permits backflow of blood from the left ventricle into the left atrium during ventricular systole.
Increased atrial pressure causes pulmonary hypertension and failure of the right ventricle.
The overall clinical and hemodynamic picture mimics and may be confused with that of constrictive pericarditis.
Mitral stenosis is two to three times more common in women than in men.
The risk of developing atrial dysrhythmias (especially fibrillation) and dysrhythmia-induced thrombi is high.
Aortic valve degeneration with aging is associated with lipoprotein deposition in the tissue with chronic inflammation and leaflet calcification.
Outflow obstruction increases pressure within the left ventricle in aortic stenosis.
Ischemia can cause attacks of angina in aortic stenosis.
Elevated white blood cell count, erythrocyte sedimentation rate, and CRP.
Rheumatic fever is caused by a delayed immune response to infection by group A beta-hemolytic streptococci.
In cases of chronic recurrent rheumatic fever or carditis.
A general term used to describe infection and inflammation of the endocardium, especially the cardiac valves.
Inflammation in rheumatic fever is found in various sites including the endocardium, myocardium, and pericardium.
Bacteria infiltrate the sterile thrombi and activate the clotting cascade.
The left ventricle becomes dilated and hypertrophied to maintain adequate cardiac output.
RHD begins as carditis, or inflammation of the heart.
Rheumatic heart disease and infective endocarditis are less common causes.
The earliest cardiac manifestation may be a previously undetected murmur caused by mitral or aortic semilunar valve dysfunction.
Studies suggest an autosomal dominant and X-linked inheritance pattern.
Cardiac auscultation may disclose a regurgitant murmur or midsystolic click in an otherwise healthy individual.
Increased resistance to ventricular ejection commonly seen in hypertension or in valvular stenosis (usually aortic).
Cardiomegaly and dysrhythmias are common.
Transcatheter aortic valve implantation.
The severity of the valvular dysfunction and the capacity of the heart to compensate determine the symptoms and degree of incapacitation.
Nearly 2% of adults older than 65 years are affected by aortic stenosis.
Pulmonary congestion and right heart failure.
Some of the ejected blood flows back into the left ventricle during diastole.
Ventricular hypertrophy.
Clinical manifestations of aortic stenosis include decreased stroke volume, reduced systolic blood pressure, and narrowed pulse pressure.
Acute rheumatic fever is characterized by inflammation of the joints, skin, nervous system, and heart.
When the murmur has disappeared or cardiac status becomes stable, major manifestations are no longer present, the individual is afebrile, and the erythrocyte sedimentation rate is normal or stabilized.
Approximately 15,000 new cases.
The most distinctive inflammatory lesions within the heart in rheumatic fever are called Aschoff bodies.
The volume of backflow reentering the left atrium gradually increases, causing atrial dilation and associated atrial fibrillation.
Carditis in rheumatic fever can affect all three layers of the heart wall: endocardium, myocardium, and pericardium.
Pericardial inflammation is usually characterized by serofibrinous effusion within the pericardial cavity.
Chest pain is caused by pericardial inflammation.
Each joint remains symptomatic for approximately 2 to 3 days.
Individuals may be asymptomatic or may complain of angina, syncope, dyspnea on exertion, and palpitations.
Death occurs as a result of heart failure or dysrhythmias.
Increased pressure in the chamber to overcome resistance to flow through the valve causes the myocardium to work harder, causing myocardial hypertrophy.
They depend on the size of the valvular orifice.
Aortic stenosis is associated with many risk factors for coronary artery disease.
Disorders in calcium transport, apoptosis of endocardial cells, and decreased nitric oxide synthesis have been implicated in aortic stenosis.
Aortic stenosis tends to develop gradually.
They are more useful in identifying an acute inflammatory process and suggesting prognosis than in diagnosing acute rheumatic fever.
Untreated rheumatic fever can cause scarring and deformity of cardiac structures, resulting in rheumatic heart disease (RHD).
50% to 65%.
Viruses, fungi, rickettsia, and parasites.
Antibodies cross-react within neuronal cells, triggering dopamine release.
Several genes, including the HLA-DR 1 antigen and HLA-DR 6 antigen, have been implicated in RHD.
Mitral valve prolapse is the most common valve disorder in the United States.
Palpable subcutaneous nodes often develop over bony prominences and along extensor tendons.
Heat, such as from bathing, darkens the rash.
It may occur idiopathically or as a cardiac manifestation of systemic diseases such as scleroderma, amyloidosis, sarcoidosis, lymphoma, and hemochromatosis, or a number of inherited storage diseases.
Most require valve repair or replacement with a prosthetic valve followed by long-term anticoagulation.
Acute rheumatic fever.
Continued increases in left atrial volume and pressure.
Approximately 2% to 5% of adults with degenerative sclerotic aortic valves progress to aortic stenosis.
The narrowing of the aortic semilunar valve causes diminished blood flow from the left ventricle into the aorta.
The classic manifestations of aortic stenosis are angina, syncope, and heart failure.
The levels of these tests decrease.
Cardiac glycosides, diuretics, and bed rest may be added to the regimen.
Continuous prophylactic antibiotic therapy for as long as 5 years.
Endocardial damage, blood-borne microorganism adherence to the damaged endocardial surface, and formation of infective endocardial vegetations.
Adhesins.
The most common causes of mitral regurgitation are mitral valve prolapse and rheumatic heart disease.
Mitral regurgitation gives rise to a loud pansystolic murmur heard best at the apex that radiates into the back and axilla.
Mitral incompetence is usually well tolerated—often for years—until ventricular failure occurs.
The valves lose their elasticity, and the leaflets may adhere to each other, leading to scarring and shortening of the involved structures.
About 50% of patients with acute rheumatic fever develop carditis.
Mitral valve prolapse tends to be most prevalent in young women.
Many cases of mitral valve prolapse are completely asymptomatic.
Streptolysin-O is a hemolytic factor produced by most strains of group A beta-hemolytic streptococci.
Examination may reveal extra heart sounds and murmurs.
Disorders of the endocardium damage the heart valves, which are made up of endocardial tissue.
In valvular regurgitation, the valve leaflets or cusps fail to shut completely, permitting blood flow to continue even when the valve is supposed to be closed.
Management almost always includes careful fluid management, valvular repair, or valve replacement with a prosthetic valve followed by long-term anticoagulation.
A rumbling decrescendo diastolic murmur.
Aortic regurgitation.
The coronary arteries may not be able to supply the increased myocardial oxygen demand in aortic stenosis.
Beta-blockers might be needed to alleviate syncope, severe chest pain, or palpitations in mitral valve prolapse.
Heart rate is often slow in aortic stenosis.
There is little evidence that anti-inflammatory medications (including corticosteroids) are effective in treating acute carditis.
Rheumatic fever tends to run in families, lending support to the concept of genetic predisposition, including changes in major histocompatibility antigens.
Antibodies against a streptococci bacterial wall antigen (GlcNAc) display cross-reactivity with tissue glycoproteins in the heart, joints, and other tissues.
The formation of a sterile thrombus on the membrane.
Other causes include infective endocarditis, CAD, connective tissue diseases (Marfan syndrome), and congestive cardiomyopathy.
Left ventricular function may become impaired to the point of failure.
Endocardial inflammation causes swelling of the valve leaflets, with secondary erosion along the lines of leaflet contact.
Cardiac complications include extra heart sounds, heart block, atrial fibrillation, and a prolonged PR interval.
There may be a relationship between symptomatic mitral valve prolapse and hyperthyroidism.
The rash consists of nonpruritic, pink, erythematous macules that never occur on the face or hands.
Restrictive cardiomyopathy is characterized by restrictive filling and reduced diastolic volume of either or both ventricles with normal or near-normal systolic function and wall thickness.
Acquired forms cause inflammatory, ischemic, traumatic, degenerative, or infectious alterations of valvular structure and function.
Valvular dysfunction stimulates chamber dilation and/or myocardial hypertrophy, both of which are compensatory mechanisms intended to increase the pumping capability of the heart.
Lifelong antibiotic prophylaxis prior to invasive procedures is required in the case of mechanical valve replacement.
A sharp noise called an opening snap.
Rheumatic heart disease, bacterial endocarditis, syphilis, hypertension, connective tissue disorders, appetite-suppressing medications, trauma, or atherosclerosis.
Many symptoms of mitral valve prolapse are vague and puzzling and are unrelated to the degree of prolapse.
Widened pulse pressure.
Dysrhythmias and endocarditis.
The incidence of acute rheumatic fever declined due to medical and socioeconomic improvements, as well as changes in the virulence of group A streptococci.
Yes, individuals who have experienced one attack of acute rheumatic fever are more susceptible than the general population to recurrent attacks.
Rheumatic fever is suspected as a hypersensitivity reaction, proposed to be caused by antibodies directed against the M proteins of certain strains of streptococci that cross-react with tissue glycoproteins in the heart, joints, and other tissues.
During injection drug use, trauma, dental procedures, cardiac surgery, genitourinary procedures, indwelling catheters, or from uncomplicated upper respiratory or skin infections.
Antibodies also affect skin, muscles, and synovial joints.
The involvement of HLA-DR antigens suggests that genetically determined immune response factors may play a role in the pathogenesis of severe chronic RHD.
The small beadlike clumps are called vegetations and contain platelets and fibrin.
Mitral valve prolapse syndrome is a condition in which the anterior and posterior cusps of the mitral valve billow upward into the atrium during systole.
The prevalence of mitral valve prolapse is estimated at 2.4%.
Sydenham chorea, or St. Vitus dance, is a disorder of the CNS characterized by sudden, aimless, irregular, involuntary movements.
A throat culture positive for group A beta-hemolytic streptococci can be an important finding when associated with certain physical signs.
Treatment is aimed at the underlying cause.
In valvular stenosis, the valve orifice is constricted and narrowed, impeding the forward flow of blood and increasing the workload of the cardiac chamber proximal to the diseased valve.
The leaflets become fibrous and fused, and the chordae tendineae cordis becomes shortened.
Less than 10% of aortic stenosis cases are caused by rheumatic heart disease.
More aggressive lipid lowering in adults might decrease the prevalence of degenerative aortic stenosis.
Most individuals with mitral valve prolapse have an excellent prognosis, do not develop symptoms, and do not require any restriction in activity or medical management.
High-risk individuals with mitral valve prolapse can be identified by clinical and echocardiographic findings.
As anti-inflammatory agents for rheumatic carditis and arthritis to help relieve symptoms.
1 to 6 months.
Bacteria, especially streptococci, staphylococci, and enterococci.
Valve replacement may be delayed for many years through careful use of vasodilators and inotropic agents.
Cardiac myosin is another target antigen in rheumatic fever.
The valve structures stretch and become deformed, leading to further backflow.
The primary lesion usually involves the endocardium, which includes the heart valves.
The common symptoms of acute rheumatic fever are fever, lymphadenopathy, arthralgia, nausea, vomiting, epistaxis, abdominal pain, and tachycardia.
Mitral regurgitation occurs if the ballooning valve permits blood to leak into the atrium.
Exudative synovitis causes these symptoms.
Erythema marginatum is a distinctive truncal rash that often accompanies acute rheumatic fever.
Diastolic dysfunction develops first, leading eventually to systolic dysfunction of the ventricle.
Mitral stenosis impairs the flow of blood from the left atrium to the left ventricle.
Echocardiography can assess the severity of valvular obstruction or regurgitation before the onset of symptoms.
Pulmonary hypertension, edema, and right ventricular failure.
Valve replacement.
The end-diastolic volume of the left ventricle increases and myocardial fibers stretch to accommodate the extra fluid.
Heart failure.
Large stroke volume and rapid runoff of blood from the aorta.
The systolic heart murmur is heard best at the second intercostal space and may radiate to the neck in aortic stenosis.
Initiation of antibiotic therapy 2 weeks after the start of streptococcal infection does not prevent rheumatic fever in susceptible individuals.
Acute rheumatic fever affects the heart, joints, CNS, and skin through an abnormal humoral and cell-mediated immune response to the M proteins on the microorganisms that cross-react with normal tissues.
Approximately 10% of cases of rheumatic fever develop into RHD.
Surgical repair must be done emergently.
Pulmonic valve dysfunction can have the same consequences as tricuspid valve dysfunction.
Pericardial effusion produces an audible friction rub.
It is thought to result from a genetic or environmental disruption of valvular development during the fifth or sixth week of gestation.
Echocardiography may demonstrate the prolapsed mitral valve.
Myocardial contractility is diminished, the ejection fraction is reduced, diastolic pressure increases, and the affected heart chamber fails from overwork.
Aortic stenosis is the most common valvular abnormality.
The first heart sound (S1).
More than a third.
Compensatory dilation.
High-risk individuals with mitral valve prolapse are at increased risk for complications such as infective endocarditis, cardioembolic stroke, and sudden death.
Pulses are faint in aortic stenosis.
Rheumatic fever continues to be a major cause of death and disability for underprivileged populations because crowding and poor hygiene are environmental risk factors.
Acute rheumatic fever can develop only as a sequel to pharyngeal infection by group A beta-hemolytic streptococci.
Trauma, congenital heart disease, valvular heart disease, and the presence of prosthetic valves.
Cross-reactivity against laminin is when antibodies target laminin, a protein present in extracellular tissues around heart cells and in the valves.
Autoimmunity and intense inflammation result in diffuse, proliferative, and exudative lesions in the connective tissues, especially in the heart, joints, and skin.
Tricuspid regurgitation is usually associated with dilation and failure of the right ventricle secondary to pulmonary hypertension.
The most common cause of mitral valve prolapse is myxomatous degeneration of the leaflets.
Acute migratory polyarthritis is the inflammation of more than one joint, occurring in 60% to 80% of individuals with rheumatic fever.
Sydenham chorea is more common in girls than in boys.
A high or rising ASO antibody titer is an accurate means of diagnosing rheumatic fever.
Inflammation may subside before treatment, leaving behind damage to the heart valves and increasing susceptibility to recurrent acute rheumatic fever.
Most clinical manifestations are caused by heart failure.
If inflammation penetrates the myocardium, localized fibrin deposits develop, surrounded by areas of necrosis, called Aschoff bodies.
The cusps are redundant, thickened, and scalloped because of changes in tissue proteoglycans, increased proteinases, and infiltration by myofibroblasts.
The large joints of the extremities are most often affected.
Sydenham chorea typically resolves within 1 to 6 months.
Tricuspid regurgitation is more common than tricuspid stenosis.
The major clinical manifestations usually occur singly or in combination 1 to 5 weeks after streptococcal infection of the pharynx.
Endocardial inflammation may manifest years later with serious valvular diseases (stenosis and regurgitation) and recurrent infective endocarditis.
Other neuroendocrine abnormalities include polymorphisms of the angiotensin II type 1 (AT1) receptor and alterations in ANS function.
Criteria for the diagnosis of rheumatic fever have been developed and updated by both the AHA and the World Health Organization.
Tricuspid valve incompetence leads to volume overload in the right atrium and ventricle, increased systemic venous blood pressure, and right heart failure.
The chordae tendineae may be elongated, permitting the valve cusps to stretch upward.
Mitral valve prolapse is often associated with Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta.
