32A.Feb.5.18.ValveDiseases

6.Aortic Valve Stenosis.Overview

Aortic Valve Stenosis occurs due to incomplete opening of the aortic valve thus preventing proper emptying of the left ventricle into the systemic circulation during systole.

9.Tricuspid Valve Regurgitation.Overview

Tricuspid Valve Regurgitation refers to inappropriate retrograde movement of blood from the right ventricle to the right atrium during systole.

7.Aortic Valve Regurgitation.Clinical Consequences

1.Acute Aortic Regurgitation As described above, rapid development of severe pulmonary edema results in intense dyspnea. In many cases, CARDIOGENIC Shock develops. 2.Chronic Aortic Regurgitation Chronic Aortic Regurgitation can be well-tolerated for many years without significant symptomology. Patients often present only once signs and symptomology of LEFT HEART FAILURE have developed such as DYPSNEA, ORTHOPENIA, and PAROXYSMAL NOCTURNAL DYSPNEA. In some cases, patients manifest with anginal chest pain due to episodes of myocardial ischemia, as described above.

4.Mitral Valve Stenosis.Complication

1.CHF 2.AF 3.PE 4.Endocarditis

6.Aortic Valve Stenosis.Complication

1.CHF 2.LV dysfunction 3.Endocarditis 4.PE 5.Ischemia/Infarction

3.Infective Endocarditis.ClinicalConsequences

1.Cardiac Consequences The presence of vegetations often results in physical damage to the underlying endocardium. When vegetations are present on heart valves this can give rise to or aggravate pre-existing Valvular Heart Disease. For example, large vegetations can lead to valvular stenosis but more commonly destruction of the heart valve leads to valvular regurgitation. Acute endocarditis can cause valvular damage rapidly, within days, whereas damage following a subacute course can progressively worsen over months. Often, infective endocarditis can be detected by the development of new or changing heart murmurs representing new or evolving valvular damage. 2.Embolization The extra-cardiac clinical consequences of infective endocarditis are primarily due to embolization of vegetations which can seed nearly any organ

7.Aortic Valve Regurgitation.Signs

1.Heart Murmur: The prototypical auscultory finding of aortic regurgitation is a blowing, decrescendo diastolic murmur caused by the dissipating jet of regurgitating blood. 2.Widened Pulse Pressure: In cases of severe chronic aortic regurgitation the rapid dissipation of systemic diastolic pressure results in a significant widening of the pulse pressure. This manifests as a number of different physical findings but most prominently as "Water-hammer" pulses which fall rapidly during diastole (Also known as Corrigan's Pulse). In addition, pulses in the carotids may be so widened that a patients head may bob to-and-fro, known as de Musset Sign.

6.Aortic Valve Stenosis.Signs

1.Heart Murmur: Aortic stenosis often results in a low-pitched, rough-sounding murmur that rises after S1, is loudest in the middle of systole, and disappears before S2 2.Pulses Parvus et Tardus: Peripheral pulses are often weak (parvus), reflecting a reduced pulse pressure, and late (tardus) 3.S4: Strong atrial contraction against a hypertrophied, stiff left ventricle often results in a fourth heart sound.

7.Aortic Valve Regurgitation.Pathophysiology

1.Overview Aortic Regurgitation allows a portion of the forward volume output of the heart to return to the left ventricle. Consequently, the left ventricle is filled with the normal volume it receives from the left atria in addition to the regurgitant volume, resulting in elevation of the Left Ventricular End Diastolic Volume (VEDV). Because of the Frank-Starling Relationship, this substantial increase in left ventricular PRELOAD improves ventricular ejection and consequently cardiac output is initially not compromised. However, several pathophysiological sequelae result which can lead to severe clinical consequences. The subsequent pathophysiological progression is largely dependent on the timescale, acute or chronic, in which regurgitation develops. 2.Acute Aortic Regurgitation Acute Aortic Regurgitation primarily occurs in the context of aortic dissection and in some cases of infective endocarditis. Regurgitation into an otherwise normal left ventricle results in substantial increases in diastolic ventricular pressures. These pressures in turn necessitate higher left atrial pressures to maintain sufficient ventricular filling. Greater left atrial pressures are in turn retrogradely transmitted into the pulmonary circulation, ultimately resulting in sudden and severe pulmonary edema. Causes:Dissection, trauma, endocarditis, prosthetic valve failure 3.Chronic Aortic Regurgitation a.The chronic presence of aortic regurgitation allows for significant compensatory remodeling of the left ventricle. The left ventricle compensates for chronic volume overload by undergoing ECCENTRIC VENTICULAR HYPERTROPHY and thus chamber dilation. This allows the regurgitant volume to enter the left ventricle without significantly increasing diastolic filling pressures, thus avoiding backward transmission of that pressure to the pulmonary circulation and in turn preventing pulmonary edema. However, when regurgitatant volumes are large, the systemic arterial pressure rapidly falls during diastole as much of the ejected blood returns to the dilated left ventricle. b.Because the majority of cardiac blood flow occurs during diastole, reduced diastolic pressure can significantly reduce coronary perfusion to the point that transient episodes of myocardial ischemia are encountered. Furthermore, as the left ventricle dilates, the Law of Laplace dictates that the myocardial tension required to achieve ventricular ejection increases, thus effectively increasing the left heart's AFTERLOAD. In consequence, the dilating left ventricle encounters a situation of chronically increased PRELOAD and AFTERLOAD, an unsustainable hemodynamic burden which ultimately leads to LEFT HEART FAILURE in many patients.

6.Aortic Valve Stenosis.Clinical Consequences

1.Overview Aortic Stenosis can remain subclinical for many years as the heart possesses significant functional reserve and left ventricular hypertrophy can successfully compensate for the increased afterload. Eventually, a set of prototypical symptoms manifests and result from the episodic myocardial ischemia and progressive left heart failure described above. 2.Angina The mismatch generated by the reduced cardiac blood flow and increased cardiac oxygen demand render the heart highly prone to episodes of myocardial ischemia. This manifests as anginal chest pain very similar in quality to that observed in stable angina. 3.Syncope The stenotic aortic valve prevents the heart from substantially increasing cardiac output when required. This is especially true during bouts of physical activity when the systemic vascular resistance can decline due to increased muscle activity. Consequently, a hallmark of aortic stenosis is exertional syncope. 4.Dyspnea As mentioned, left atrial hypertrophy can prevent mean left atrial pressures from rising during the early stages of disease. However as time wears on and stenosis becomes more severe, the failing left heart is unable to eject sufficient blood volume during systole. This requires increasingly sustained high diastolic left atrial pressures to fill the ventricle which is transmitted retrogradely into the pulmonary circulation, resulting in pulmonary edema, and thus dyspnea. Over time, the full clinical syndrome of left heart failure develops

5.Mitral Valve Regurgitation.Clinical Consequences

1.Overview As described above the pathophysiological sequelae of acute and chronic mitral valve regurgitation are substantially different and are reflected in their distinct clinical presentation. Acute mitral regurgitation is dominated by increased left atrial pressures and thus pulmonary edema. In contrast, chronic mitral regurgitation is dominated by reduce cardiac output. 1.Acute Mitral Regurgitation Patients with acute mitral regurgitation present with signs and symptomology of severe, rapidly progressive pulmonary edema such as profound dyspnea that constitutes a MEDICAL EMERGENCY. 2.Chronic Mitral Regurgitation Mild chronic mitral regurgitation is usually subclinical as the heart possesses significant functional reserve. Patients with chronic moderate regurgitation often display signs of deficient cardiac output which present as fatigue and an intolerance to physical exertion. If chronic regurgitation is severe then left atrial pressures do eventually rise to the point that signs and symptoms of pulmonary edema begin to manifest, first as dyspnea and then progressing to orthopnea. In such severe cases, chronic volume overloading of the left ventricle can lead to left heart failure which aggravates pulmonary hypertension and often yields concomitant right heart failure. Whatever the severity, dilation of the left atrium can cause atrial fibrillation.

4.Mitral Valve Stenosis.Clinical Consequences

1.Overview In general, patients usually present with stenotic symptoms more than 20 years after the initial attack of rheumatic fever. 2.Dyspnea is the dominant symptom of mitral stenosis and manifests with varying severity depending on the degree of stenosis. With mild stenosis, Dyspnea may manifest only under conditions that require increased cardiac output such as physical activity or emotional excitement. As stenosis intensifies Dyspnea may be encountered at rest and may evolve to include orthopnea and paroxysmal nocturnal dyspnea. 3.Right Heart Failure Chronic pulmonary hypertension can substantially increase the demand on the right heart. Over time, this may lead to the congestive symptomology of Right Heart Failure (see page). 4.Hemoptysis In certain cases, increased pulmonary venous pressures will cause opening of collateral channels between the pulmonary and bronchial circulation. Rupture of these collaterals may manifest as hemoptysis. 5.Complications As mentioned above, atrial fibrillation, thromboembolism, and infective endocarditis may develop secondary to mitral valve stenosis.

2.Mitral Valve Prolapse.ClinicalConsequences

1.Overview In most cases MVP is completely asymptomatic and is discovered incidentally due to auscultation of a characteristic "Mid-systolic Click" followed by a late systolic heart murmur. These auscultory findings reflect the sudden tension encountered by the loose, elongated chordae tendineae midway during systole as the mitral valve is forced into the left atrium, followed by the sounds of mild mitral regurgitation. 2.Complications Occasionally, the loose chordae tendineae can rupture resulting in severe, acute mitral regurgitation, comprising a medical emergency. The Mitral Valve of those with MVP appears to be more prone to infective endocarditis. Finally, patients with MVP are prone to ventricular arrhythmias for cryptic reasons.

9.Tricuspid Valve Regurgitation.Etiologies

1.Overview In most cases tricuspid regurgitation is due to a functional defect in tricuspid valve closure, secondary to dilation of the tricuspid annulus, rather than a structural derangement of the valve leaflets themselves. Consequently, processes which result in right ventricular eccentric hypertrophy can give rise to tricuspid regurgitation. 2.Functional Tricuspid Regurgitation In general, any pathophysiological process that leads to SEVERE PULMONARY HYPERTENSION will result in RIGHT VENTRICULAR HYPERTROPHY which in its end-stage takes a eccentric pattern, enlarging the tricuspid annulus, and thus potentially leading to Tricuspid Regurgitation. In many cases, pulmonary hypertension arises in contexts of left heart failure which are frequently secondary to myocardial infarction or mitral stenosis. Less commonly, RIGHT VENTRICULAR DILATION secondary to dilated cardiomyopathy or direct right ventricular myocardial infarction can also be a culprit. 3.Structural Tricuspid Regurgitation Structural defects of the tricuspid valve are much rarer causes of tricuspid regurgitation. These include infective endocarditis affecting the tricuspid valve, usually observed in IV drug abusers. Patients with carcinoid syndrome develop plaques affecting the tricuspid valve possibly caused by high levels of circulating serotonin metabolites released by the tumor. These plaques structurally derange the Tricuspid leaflets and can lead to regurgitation.

7.Aortic Valve Regurgitation.Etiologies

1.Overview Insufficiency of the aortic valve may be due to primary disease of the valve leaflets preventing their full closure; alternatively, several primary diseases of the aortic root result in widening of the valvular annulus and thus prevent full closure of otherwise healthy aortic valve leaflets. 2.Primary Leaflet Disease a.Congenital Bicuspid Aortic Valve: Interferes with full valvular coaptation. b.Infective Endocarditis: Can cause perforation or physical destruction of the valve leaflets c.RHUEMATIC Fever: In some patients Rheumatic Heart Disease results in sclerosis and deformation of the aortic valve 3.Primary Aortic Root Disease a.Aortic Dissection: Specifically Type A dissections which extend into the aortic root b.Syphilitic Aneurysm: Can occur during Tertiary Syphilis c.Aortic Aneurysms: Aneurysmal dilation of the aorta is sometimes seen in patients with Marfan Syndrome and some other familial diseases.

5.Mitral Valve Regurgitation.Pathophysiology

1.Overview Mitral Regurgitation results in some portion of the stroke volume ejected by the left ventricle entering the left atrium rather than the systemic circulation. This not only increases the left atrial pressure but also reduces the heart's total cardiac output. A number of factors determine what percentage of the stroke volume inappropriately enters the atrium; however, the most important factor appears to be the relative ease with which the ventricle can eject blood into the atrium. 1.Acute Atrial Regurgitation During acute atrial regurgitation, atrial compliance is relatively low; consequently, atrial pressures rapidly rise even with small regurgitant volumes, thus directing the majority of the stroke volume appropriately into the systemic circulation. As a result, cardiac output is not severely compromised; however, the sharp rise in left atrial pressures are retrogradely transmitted to the pulmonary circulation rapidly resulting in profound pulmonary edema and thus dyspnea. 2.Chronic Atrial Regurgitation Long-term mitral regurgitation allows the left atrium to undergo remodeling and thus atrial dilation which substantially increases atrial compliance. When atrial compliance is high, the atrium can accommodate large blood volumes from the ventricle without a large increase in pressure, allowing much of the stroke volume to empty into the atrium. While this prevents sharp rises in left atrial pressure and protects the pulmonary circulation from edema, cardiac output is severely compromised as much of the stroke volume enters the atria rather than the systemic circulation. Consequently, the signs and symptomology of chronic mitral regurgitation center around poor cardiac output which manifests as fatigue and weakness.

5.Mitral Valve Regurgitation.Etiologies

1.Overview Proper closure of the mitral valve during systole requires the structural integrity of the valvular leaflets and annulus as well as proper functionality of the papillary muscles and chordae tendineae. A wide variety of etiologies can result in defects in any of these components and thus result in Mitral Regurgitation. We categorize these etiologies according to whether resultant regurgitation develops acutely or chronically. 2.Acute Etiologies a.Infective Endocarditis: Infection perforates valve leaflets or ruptures chordae tendineae b.Myocardial Infarction: Dysfunction or rupture of papillary muscles 3.Chronic Etiologies a.Mitral Valve Prolapse: Progressive structural weakening of the mitral valve leaflets b.RHEUMATIC Fever: Fibrotic deformation of the leaflets and shortening of the chordae tendineae prevent valvular closure. Is less common that rheumatic mitral stenosis but both can co-exist c.Ventricular Dilation: May be due to dilated cardiomyopathy or eccentric ventricular hypertrophy associated with end-stage left heart failure or myocarditis. Whatever the case, expansion of the mitral anulus prevents proper closure of the leaflets d.Marfan Syndrome: Weakening of the valve leaflets and chordae tendineae.

6.Aortic Valve Stenosis.Etiologies CALCIFICATION.BICUSPID.RHEMATIC

1.Overview Sclerosis (a hardening of tissue) and CALCIFICATION of the aortic valvular cusps are the ultimate pathological changes which lead to aortic stenosis. These morphological changes thicken and harden the cusps, resulting in poor opening of the aortic valve, and thus stenosis of the aortic valve outlet. Chronic hemodynamic shear forces and turbulent flow across these cusps are likely the root cause of progressive sclerosis and thickening. In individuals with anatomically normal aortic valves, such changes may take years to result in sclerotic and calcific pathology and thus disease manifests late in life, if ever. However, in individuals with preexisting aortic valvular deformities which enhance shear forces and turbulence, pathological progression is accelerated and disease may manifest much earlier in life. Below we discuss the most common etiologies that lead to aortic stenosis. 2.Age-related Degenerative Calcific Aortic Stenosis Age related hemodynamic wear-and-tear of the aortic valve is the most common etiology of aortic stenosis. In fact, the aortic valves of nearly a third of all individuals older than 65 display some sclerotic pathology although much fewer display clinical signs of aortic stenosis. When clinical consequences do arise, they generally manifest late in life, in the seventh and eighth decade. 3.Congenitally-affected Valves Some patients display congenital malformations of their aortic valves, such as a CONGENITAL BICUSPID AORTIC VALVE , which result in abnormal patterns of hemodynamic stress. Chronic exposure of the aortic valve to such stresses from an early age results in more rapid progression of sclerotic and calcific pathology, which can lead to signs of frank stenosis in adult life. 4.RHEUMATIC Heart Disease Some patients who develop Rheumatic Heart Disease as a complication of Rheumatic Fever develop malformations of their aortic valves during adult life. Once again, such malformation likely expose the aortic valves to additional hemodynamic stresses which accelerate progression of sclerotic and calcific pathology. Consequently, clinical signs of aortic stenosis may develop during the adult years.

6.Aortic Valve Stenosis.Pathophysiology

1.Overview Stenosis of the aortic outlet generates significant resistance to left ventricular outflow of blood during systole. Consequently, a significantly higher blood pressure gradient between the left ventricle and the aorta is required to maintain cardiac output at a normal level. This substantially increases the AFTERLOAD on the left ventricle and in doing so significantly raises the cardiac oxygen demand. Because all etiologies of aortic valve stenosis develop over years, sufficient time exists for the heart to undergo significant remodeling to alleviate the chronically high afterload. Remodeling initially follows a pattern of CONCENTRIC VENTRICULAR HYPERTROPHY in which the ventricle becomes significantly thickened. The increased thickness of the ventricular wall reduces myocardial tension, courtesy of the Law of Laplace, and thus serves to reduce AFTERLOAD. With such changes the normal ventricle is able to maintain cardiac output in most situations for years; however, as time progresses or the stenosis becomes more severe, the following pathophysiological sequelae may arise. 3.Transient Myocardial Ischemia Although ventricular hypertrophy reduces the myocardial tension required for successful ventricular ejection, it also stiffens the left ventricle, reducing its passive compliance for filling during diastole. Consequently, substantially increased diastolic filling pressures are required to successfully fill the ventricle. Because most of the blood flow to the myocardium occurs during diastole, increased diastolic filling pressures significantly reduce the blood pressure gradient for cardiac perfusion, and thus reduce cardiac blood flow. REDUCED CARDIAC PERFUSION TOGETHER WITH INCREASED CARDIAC OXYGEN DEMAND from the hypertrophied ventricular myocardial mass can result in transient episodes of MYCOCARDIAL ISCHEMIA, especially during physical activity. 4.Left Heart Failure The increased diastolic filling pressures mentioned above are initially achieved by enhancing left atrial systole (See: Cardiac Cycle) rather than a sustained increase in left atrial pressure. This avoids backward transmission of left atrial pressure to the pulmonary circulation but requires significant hypertrophy of the left atrium. Importantly, because such patients are thus highly dependent on successful atrial contraction, ATRIAL FIBRILLATION can cause rapid clinical deterioration. Eventually, however, the left ventricle cannot sustain the increased systolic pressures required to maintain cardiac output and Left Heart Failure ensues. As the left heart fails, high sustained left atrial pressures are required to fill the ventricle, resulting in backward transmission of pressure into the pulmonary circulation, consequent pulmonary edema, and the clinical syndrome of left heart failure.

4.Mitral Valve Stenosis.Pathophysiology

1.Overview Stenosis of the mitral valve considerably increases the resistance to blood flow between the left atrium and the left ventricle. To maintain a sufficient cardiac output, the blood pressure gradient between these two chambers must increase and is achieved by substantially increasing the Left Atrial Pressure (LAP). However, increased LAP results in a number of pathophysiological consequences described below. In general, increases in left atrial pressures are largely able to maintain cardiac output at rest in mild mitral stenosis although cardiac output may not rise normally with physical activity. However, as the stenosis becomes more severe, deficient cardiac output may be experienced even at rest. 2.Pulmonary Edema Increased LAP results in passive backup of blood into the pulmonary circulation and thus pulmonary edema which can manifest clinically as dyspnea. 3.Pulmonary Hypertension In most patients, pulmonary hypertension is due to passive backward transmission of the left atrial pressure. In some patients, however, there appears to be an active component to the pulmonary hypertension caused by reactive vasoconstriction of pulmonary arterioles. Whatever the case, pulmonary hypertension substantially increases the afterload on the right Heart, and often results in CONCENTRIC RIGHT VENCTRICULAR HYPERTROPY. 4.Atrial Fibrillation Chronically increased LAP will eventually result in left atrial dilation which can derange the electrophysiology of the left atrium and cause atrial fibrillation. 5.Thromboembolism Stasis of blood in a dilated left atrium can increase the risk of thrombosis within this chamber. Embolization of thrombi can result in development of systemic thromboemboli. 6.Infective Endocarditis Naturally, a deformed, fibrotic, or calcified mitral valve will increase the risk of its colonization with bacteria and thus endocarditis

4.Mitral Valve Stenosis.Signs

1.Overview Stenosis of the mitral valve results in a number of prototypical physical findings associated with changes in the valvular dynamics and hemodynamics. 2.S1 Accentuation or Delay S1 is normally caused by closure of the mitral valve and is often accentuated or delayed in the context of mitral stenosis. This may be because the larger pressure gradient between atria and ventricle during diastole maintains mitral leaflets wide apart even during late stages of diastole. As ventricular pressure ramps up during systole, the leaflets are slammed shut with greater force, generating a louder sound, or with a slight delay. However, S1 accentuation and delay tend to become mild or disappear all together in late stages of the disease. 3.Opening Snap Opening of the stenotic mitral valve generates an audible "Opening Snap" immediately after S2, likely due to tensing of the thickened chordae tendineae. The intensity of the Opening Snap is thought to correlate with the degree of mitral stenosis. 4.Heart Murmur Diastolic passage of high pressure atrial blood into the ventricle through the stenotic mitral valve generates a low-pitched, rumbling murmur best heard at the apex. Importantly, the duration of the murmur best correlates with the degree of mitral stenosis, reflecting the length of time required to dissipate the diastolic atrial-ventricular pressure gradient. Frequently, the murmur will accentuate just before systole, termed "Pre-systolic Accentuation", reflecting atrial systolic ejection of additional blood into the ventricle.

3.Infective Endocarditis.Pathogenesis

1.Overview The smooth endocardium is normally resistant to infection; however, the set of pathogenic events described below are thought to be the sequence by which the endocardium is injured and rendered prone to infection, thus forming the physical substrate upon which infective vegetations can develop. 2.Endocardial Injury Physical injury of the endocardium initiates the pathogenic sequence which ultimately leads to its infection. In most cases, injury is due to hemodynamic trauma associated with localized turbulent flow. Such turbulent flow can occur on the endocardium covering deformed heart valves or at the endocardial impact site of high-velocity jets of blood. Foreign bodies such as in-dwelling cardiac catheters or prosthetic heart valves can also incite endocardial injury. 3.Thrombus Formation Endocardial Injury results in thrombosis and the formation of an adherent thrombus at the site of injury. The consequent localized mass of fibrin and platelets is termed a "Nonbacterial Thrombotic Endocarditis (NBTE)" and likely represents the sterile precursor lesion to a full infective vegetation. It should also be pointed out that the material of prosthetic heart valves is highly prone to spontaneous thrombus formation and thus development of surface NBTEs. NBTEs are thought to provide a physical substrate upon which bacteria present within the blood stream can attach and proliferate. 4.Bacterial Entry Bacteria can gain access to the blood stream anytime a colonized epithelial surface is traumatized. Mild, transient episodes of bacteremia likely happen fairly regularly due to everyday activities such as teeth brushing or may occur more profoundly following dental procedures, surgical procedures, or IV drug abuse. Whatever the case, in most normal patients these episodes are self-limited and inconsequential. However, in individuals harboring NBTEs, hematogenous bacteria can colonize and proliferate within the adherent thrombi and in doing so damage the underlying endocardium as well as physically expand the vegetation.

1.Rheumatic Fever.Clinical Consequences

1.Overview:The acute phase occurs 2-3 weeks after pharyngeal infection although in some patients pharyngitis may be subclinical. Chronic complications arise many years after the initial infection when the child has grown to adulthood. 2.Acute Rheumatic Fever is characterized by arthralgia caused by a migrating arthritis of more than one joint (i.e. Migrating Polyarthritis). Subcutaneous nodules can appear along with a skin rash characterized by multiple pink macules with central clearing, termed "Erythema Marginatum". Cardiac inflammation can result in transient heart murmurs, tachycardia, as well as pericardial effusion, yielding a pericardial friction rub. Choreiform movements of the head and arms can occur during the acute phase and is termed "Sydenham's Chorea". 2.Chronic Rheumatic Heart Disease is characterized by deformity of heart valves. The MITRAL VALVE is most commonly affected with a subset also developing pathology of the aortic valve as well. Involvement of the tricuspid valve is rare but can occur. Mitral disease can lead to mitral regurgitation or mitral stenosis. Aortic valve disease can lead to aortic regurgitation or aortic stenosis. Rare Tricuspid Valve disease typically leads to tricuspid stenosis. The pathophysiological and clinical sequelae of these valvular lesions are discussed on their own pages and are not unique to this particular etiopathogenesis.

3.Infective Endocarditis.Epidemiology

1.Pre-existing Valvular Pathology Valvular deformities generate significant turbulent flow adjacent to the valvular endocardium. Thus, pre-existing Valvular Heart Diseases of any etiology and a history of conditions such as Rheumatic Fever which give rise to valvular deformities are major risk factors for the development of infective endocarditis. Empirically, patients with mitral regurgitation, aortic stenosis, and aortic regurgitation are those with the highest risk. Additionally, patients with hypertrophic cardiomyopathy are at an increased risk due to repeated trauma to the mitral valve as described on its respective page. 2.Prosthetic Heart Valves Patient with valvular prostheses are at a significantly greater risk of developing endocarditis not only because endocardial injury is an inherent part of their implantation but also because prostheses are less able to resist inappropriate thrombosis. Furthermore, surgical placement of prostheses often results in a transiently increased burden of bloodstream bacteria and the risk of infective endocarditis development gradually declines following valvular replacement. In developed countries, nearly 30% of all cases of infective endocarditis are associated with valvular prostheses. 3.Pre-existing High-velocity Jets Architectural defects of the heart that result in the development of high-velocity jets of blood can pre-dispose the endocardial impact sites of the jet to injury. Such jets can be created by Ventricular Septal Defects, Patent Ductus Arteriosus, or Tetralogy of Fallot. 4.IV Drug Abuse IV Drug Abusers are at a higher risk of developing infective endocarditis likely because of repeated exposure to transient bacteremic episodes associated with non-sterile injection. Because bacteria first encounter the tricuspid valve and pulmonic valve, these valves are particularly at risk for infection in this particular demographic.

6.Aortic Valve Stenosi.P/E

1.Pulsus parvus and tradus:slow and low pulse 2.Narrow pulse pressure 3.Sustained apex 4.Soft A2 5.Systolic ejection murmur 6.S4

Valve Disease

1.Rheumatic Fever.Acute.Chronic 2.Mitral Valve Prolapse 3.Infective Endocarditis 4.Mitral Valve Stenosis 5.Mitral Valve Regurgitation 6.Aortic Valve Stenosis 7.Aortic Valve Regurgitation 8.Tricuspid Valve Stenosis 9.Tricuspid Valve Regurgitation 10.Pulmonic Valve Stenosis 11.Pulmonic Valve Regurgitation 12.VSD MR TAPS

3.Infective Endocarditis.Etiology

1.Staphylococci: Mostly Staphylococcus aureus with some cases caused by Staphylococcus epidermidis 2.Streptococci: Mostly Viridans Streptococci and Enterococci 3.Other Organisms: The remaining 10% of cases can be caused by a variety of gram negative bacteria and some fungi

6.Aortic Valve Stenosis.Tx

1.Valve replacement:Bioprosthetic or mechanical 2.Transcatheter AV implant

7.Aortic Valve Regurgitation.P/E

1.Widen pulse pressure 2.Diffuse/dynamic apex 3.Bounding carotid impulse 4.Water-hammer pulse (a pulse that is bounding and forceful, rapidly increasing and subsequently collapsing, as if it were the sound of a waterhammer that was causing the pulse) 5.DuMusset sign;head bobbing 6.Duroziez sign (systolic+diastolic femoral arterial bruit (vascular murmur)

5.Mitral Valve Regurgitation.Heart Murmur

A heart murmur spanning all of ventricular systole, termed a "HOLOSYSTOLIC MURMUR", is typical of mitral valve regurgitation. In most patients with mitral regurgitation the murmur usually radiates toward the left axilla. However, in certain cases, such as dysfunction or rupture of the chordae tendineae, the regurgitant jet may be displaced from its prototypical angle and thus the murmur may radiate toward the left sternal edge, mimicking aortic stenosis. In addition, in cases of acute regurgitation, the murmur may decrescendo during systole, reflecting dissipation of the regurgitant jet as left atrial pressure rapidly rises.

7.Aortic Valve Regurgitation.Tx

Acute AR: Medical Emergency;repair or replace Chronic AR Medical 1.Afterload reduction 2.+/- diuretics 3.clinical/imaging F/U 4.Consider replacement or repair Indications for Surgery 1.Sx 2.ASx but LV systolic dysfunction 3.ASx but significant LV dilation 4.Undergoing another procedure such as CABG

7.Aortic Valve Regurgitation.Overview

Aortic Valve Regurgitation occurs due to incomplete closure of the aortic valve, thus allowing inappropriate retrograde movement of blood from the aorta to the left ventricle during diastole.

1.Chronic Rheumatic Fever

Chronic inflammation and reactive healing of the valves results in their progressive fibrosis and scarring. The consequent structural deformation of the heart valves is the most feared complication of rheumatic fever. The mitral valve and the aortic valve are the most commonly affected and can result in stenosis or regurgitation as described below.

6.Aortic Valve Stenosi.Sx

General Sx:fatigue and exercise intolerance Classic:Dyspnea chest discomfort, presyncope/syncope, sudden death

3.Infective Endocarditis.Overview

Infective Endocarditis refers to infection of the endocardium. The prototypical physical manifestation of Infective Endocarditis is termed the "Vegetation", and represents a mass of thrombotic debris and bacteria adherent to the endocardial surface with few immune cells. Infective Endocarditis can be categorized along many axes, highlighting the location of infection, the responsible bacterial species, by a patient's predisposing risk factor, or by the speed of clinical progression.

1.Acute Rheumatic Fever

Inflammation of all three layers of the heart, including the endocardium, myocardium, and epicardium. Inflammation is centered around multiple foci termed "Aschoff bodies" which represent areas of fibrinoid necrosis surrounded by mononuclear cells. Because inflammation can affect all three cardiac layers, the heart valves and pericardium are involved as well. Inflammation tends to primarily affect the mitral valve and aortic valve, leading to their edematous thickening. Inflammation of the pericardium results in fibrinous acute pericarditis and can lead to a pericardial effusion.

Choreiform movements, Sydenham's Chorea

Involuntary muscular twitching of the limbs or facial muscles

2.Mitral Valve Prolapse.Etiology

MVP may be inherited as an isolated autosomal dominant disorder or may occur as a component of Marfan Syndrome, Ehlers-Danlos Syndrome, and other connective tissue diseases. It should be pointed out that MVP is a very common disorder with nearly 2-3% of the general population displaying some features of MVP given detailed echocardiographic screening.

5.Mitral Valve Regurgitation.Tx

Medical 1.Afterload reduction, ACEi 2.Preload reduction, +/-diuretics 3.Coumadin for AF and Stroke Surgery 1.Repair or replace

9.Tricuspid Valve Regurgitation.Tx

Medical 1.Diruetics 2.Nitrates Surgery 1.Rare, annulopasty, 2.Replace

4.Mitral Valve Stenosis.Tx

Medical 1.Diuretics 2.HR lowering medication (BB) 3.Coumadin to prevent stroke Surgery. 1.Valvulopasty;also known as balloon aortic valvotomy is the widening of a stenotic aortic valve using a balloon catheter inside the valve. The balloon is placed into the aortic valve that has become stiff from calcium buildup.

2.Mitral Valve Prolapse.Overview

Mitral Valve Prolapse (MVP) is a specific disease entity which causes loosening and floppiness of the heart valve leaflets, most seriously affecting those of the mitral valve. Although often asymptomatic, MVP can lead to the development of the general pathophysiological phenomenon of mitral regurgitation

5.Mitral Valve Regurgitation.Overview

Mitral Valve Regurgitation refers to inappropriate retrograde movement of blood from the left ventricle to the left atrium through the mitral valve during systole.

4.Mitral Valve Stenosis.Overview

Mitral Valve Stenosis occurs due to improper opening of the mitral valve thus preventing normal flow of blood from the left atrium to the left ventricle during diastole.

11.Pulmonic Valve Regurgitation.Overview

Pulmonic Valve Regurgitation is usually due to a functional defect in pulmonic valve closure due to dilation of the pulmonic annulus secondary to dilative right ventricular hypertrophy. In general, any pathophysiological process that leads to severe pulmonary hypertension will result in right ventricular hypertrophy which in its end-stage takes a eccentric pattern, enlarging the pulmonic annulus, and thus potentially leading to pulmonic regurgitation. Pulmonic regurgitation can be ausultated as a decrescendo, blowing diastolic heart murmur along the left sternal border.

10.Pulmonic Valve Stenosis.Overview

Pulmonic Valve Stenosis is extremely rare and is usually due to congenital deformity of the pulmonic valve. In certain cases, high plasma levels of serotonin metabolites caused by carcinoid syndrome can result in rigidity of the pulmonic valve and thus its stenosis.

8.Tricuspid Valve Stenosis.Overview

Stenosis of the tricuspid valve is fairly rare and is most often due to sequelae of RHEUMATIC Fever. In such cases, it is usually observed in the context of rheumatic mitral stenosis.

Murmurs

Systolic:AS, PS, AR, TR Diasytolic:AR, PR, AS, TS

2.Mitral Valve Prolapse.Morphology

The Mitral Valves of those with MVP appear physically soft and floppy, resulting in their billowing into the left atrium during ventricular systole. This morphological pattern is also observed in the chordae tendineae which are often elongated, weak, and prone to rupture. Histologically, the tough fibrous central layer of the mitral valve, as well as other heart valves, and chordae tendineae are replaced with a loose, myxomatous material which has an inferior capacity to counteract physical stress

9.Tricuspid Valve Regurgitation.Clinical Consequences

Tricuspid Valve Regurgitation results in retrograde transmission of systolic ventricular pressures into the systemic veins. This results in substantial peripheral edema and ascites along with hepatomegaly and in some cases visible systolic pulsation of the liver. In addition, there is an exaggeration of the right atrial V wave as blood is forced into the right atrium during right ventricular systole.

1.Rheumatic Fever.Overview

The disease follows pediatric cases of pharyngitis caused by Streptococcus pyogenes and affects roughly 3% of children not treated with antibiotics

1.Rheumatic Fever.Morphology

The pathology of rheumatic fever develops over time and possesses both acute and chronic phases. Acute disease is due to active inflammation whereas chronic disease is likely the result of prolonged wound healing responses.

4.Mitral Valve Stenosis.Etiologies

The predominant cause of mitral stenosis is RHEUMATIC Heart Disease and occurs in nearly 40% of those with previous history Rheumatic Fever. When caused by rheumatic heart disease the mitral valve leaflets appear fibrotically thickened and calcified. The Mitral Commissures, the regions where the leaflets meet, also become fused. Together, these changes lead to stenosis of the mitral valve which interferes with proper atrial to ventricular blood flow. In many cases the chordae tendineae are thickened and shortened which can yield mitral regurgitation along with mitral stenosis. Other uncommon etiologies include congenital stenosis of the mitral valve or age-related calcification.

8.Tricuspid Valve Stenosis.Clinical Consequences

Tricuspid Valve Stenosis impedes the normal flow of blood from the right atrium into the right ventricle during diastole. Backup of blood in the right atrium increases right atrial pressure which is retrogradely transmitted into the systemic veins. The result is chronic hepatic congestion and HEPATOMEGALY along with PERIPHERAL EDEMA and ASCITES. Patients often display a prominent A Wave as atrial systole against the stenotic tricuspid valve results in an exaggerated increase in right atrial pressure and thus bulging of neck veins.

Pericardial effusion

a collection of fluid between the pericardial sac and the myocardium

arthralgia

joint pain

Erythema Marginatum

macular erythematous rash with circinate border. Usually on trunk or extremities.

8.Tricuspid Valve Stenosis.Tx

none given