242 Valvular heart diseases & congenital heart disease

Valvular disorders

-Abnormalities of valve function ~Stenosis and regurgitation-Etiology ~Congenital ~Rheumatic ~Degenerative calcification ~Infective-Diagnostic evaluation: echo-Doppler

Valvular heart disease

-Heart contains two atrioventricular valves and two semilunar valves ~AV: Right= Tricuspid. Left=Mitral or bicuspid. ~Semilunar: Right=Pulmonary. Left=Aortic

Valvular heart disease depends on:


Valvular heart disease depends on:

-Valve or valves affected-Type of functional alterations ~Stenosis ~Regurgitation ~Prolapse


-Stiffening/scarring of valve-Valve orifice is restricted-Impedes forward blood flow-Creates a pressure gradient across open valve-Degree of stenosis reflected in pressure gradient differences


-Incomplete closure of valve leaflets-Results in backward flow of blood-May be damaged- torn, inflamed, etc

Valvular heart disease

-Valvular disorders occur in children and adolescents primarily from congenital conditions and in adults from degenerative heart diseases

Mitral valve stenosis

-Large left atrial to left ventricular pressure gradient during ventricular diastole-Leads to left atrial and pulmonary congestion-Left atrial hypertrophy-May result in pulmonary hypertension and right sided heart failure -Majority of adult cases result from rheumatic heart disease

Clinical manifestations of MVS

-Dyspnea-Palpitations from atrial fibrillation-Fatigue-Low pitched rumbling diastolic murmur-CVA (stroke) ~Emboli can arise from stagnant blood in left atrium

Mitral valve regurgitation

-Majority of cases attributed to: ~MI ~Chronic rheumatic heart disease ~Isolated rupture of chordae tendineae ~Mitral valve prolapse ~Ischemic papillary muscle dysfunction ~Infectious endocarditis

Mitral valve regurgitation clinical manifestations

-Asymptomatic for years-Initial symptoms include: ~Weakness ~Fatigue ~Dyspnea that gradually progresses to orthopnea, paroxysmal nocturnal dyspnea, and peripheral edema ~Loud pansystolic murmur

Mitral valve prolapse

-Structural abnormaility of mitral valve leaflets and papillary muscles or chordae that allow leaflets to prolapse into left atrium during systole-Can occur in presence of: ~Redundant mitral valve leaflets ~Elongated chordae tendineae ~Enlarged mitral annulus ~Abnormally contracting left ventricular wall segments

Complications of mitral valve prolapse

-Usually benign but serious complications can occur ~Mitral valve regurgitation ~Infective endocarditis ~Sudden death ~Cerebral ischemia

Clinical manifestations of Mitral valve prolapse

-Most patients asymptomatic for life-Arrythmias-Tachycardia-Palpitations-Light headedness-Dizziness-Chest pain

Aortic valve stenosis

-Usually discovered in childhood, adolescence, or young adulthood-Those seen later in life usually have aortic stenosis from rheumatic fever or senile fibrocalcific degeneration of a normal valve-Usually of nonrheumatic origin-Results in obstruction of flow from left ventricle to aorta during systole-Effect is left ventricular hypertrophy and increased myocardial oxygen consumption because of increased myocardial mass-Leads to reduced CO and pulmonary hypertension

Clinical manifestations of aortic valve stenosis

-Symptoms of angina pectoris-Syncope-Heart failure ~Occurs when valve orifice is 1/3 normal size-Systolic crescendo-decrescendo murmur that ends before second heart sound

Etiology of aortic valve regurgitation

-Bacterial endocarditis-Trauma-Aortic dissection ~Constitutes life-threatening emergency-Rheumatic heart disease-Congenital bicuspid aortic valve-Syphillis

Aortic valve regurgitation

-Physiological consequence: ~Retrograde blood flow from ascending aorta to left ventricle >results in volume overload-initially, left ventricle compensates by dilation and hypertrophy-Myocardial contractility eventually declines-Pulmonary hypertension and right ventricular failure develop

Clinical manifestations of aortic valve regurgitation

-Diastolic murmur-Sudden cardiovascular collapse-Weakness-Dyspnea, severe dyspnea, orthopnea, and paroxysmal nocturnal dyspnea-Hypotension

Cyanotic congenital heart defect

-Tetralogy of fallot-Transposition of the great vessels-Eisenmenger's syndrome

Acyanotic congenital heart defect

-Atrial septal defects-Ventricular septal defect-Patent ductus arteriosus-Coarction of the aorts-Pulmonary stenosis-Aortic stenosis

Signs and symptoms of childhood congenital heart disease

-Symptoms associated with altered heart action (fatigue, dyspnea, etc)-Heart failure-Pulmonary vascular disorders-Difficulty in supplying the peripheral tissues with oxygen and other nutrients-Diagnostic studies ~Echocardiogram ~Cardiac catheterization ~Chest xray ~EKG ~MRI

Fetal circulation

-Foramen ovale-Ductus arteriosus-Above structures allow blood to bypass the pulmonary circulation

Atrial Septal defect

-About 10% of congenital heart defects-More common in males-Associated with specific genetic syndromes-Causes left to right shunt-Small defects are well tolerated and many close spontaneously

Ventricular septal defect

-Most common congenital heart anomaly-Equal incidence in males and females-Frequently associated with other cardiac defects-Shunt is initially left to right-Large defects may be identified at birth and treated surgically-Small defects often close spontaneously

Process of VSD

1.Left to right shunt2. Increased pulmonary blood flow3. Pulmonary hypertension and right ventricular hypertrophy4. Increased pressure in R ventricle5. Reversal of shunt6. Cyanosis

Patent ductus arteriosus

-About 10% of congenital heart defects-More common in females-More common in premature and low birthrate infants-Left to right shunt-Often closes spontaneously

Coarction of aorta

-Narrowing or stricture of the aorta-Common defect-Much more common in boys-If severe, blood to lower body is only through ductus arteriosis -Right sided heart failure-Usually repaired surgically

Defining features of tetralogy of Fallot

-Ventricular septal defect-Overriding aorta-Pulmonary stenosis-Right ventricular hypertrophy leads to cyanosis

Risk factors for tetralogy of fallot

-Maternal viral illness-Poor nutrition or diabetes during pregnancy-Down syndrome

Tetralogy of Fallot

-Most common cyanotic defect-10% of cases of CHD-Slightly higher incidence in males-Must be repaired surgically-Cyanosis is dure to deoxygenated blood from right ventricle entering the overriding aorta-"Tet" spells-Severity of symptoms depends on degree of pulmonary stenosis-If untreated will lead to infective carditis, secondary polycythemia-Treated surgically in infancy

Transposition of the great vessels

-Aorta arises from the right ventricle, and the pulmonary artery arises from the left ventricle-Incompatible with life unless there is another defect that allows blood to mix-Severe cyanosis-Repaired surgically very early

Eisenmenger syndrome

-Occurs in CHD with large right to left shunts-Increased pulmonary flow causes pulmonary hypertension-Pressure on the right side of heart increases-Shunt reverses causing deoxygenated blood to enter L ventricle-Patient experiences dyspnea, cyanosis, fatigue, syncope, poor feeding behavior.-Shunt reversal happens between infancy and late adult hood-May require heaty-lung transplant

Process of Eisenmenger syndrome

1. Left to right shunt2. Increased pulmonary blood flow3. Pulmonary hypertension and right ventricular hypertrophy4. Increased pressure in R ventricle5. Reversal of shunt6. Cyanosis

Common valve disease

-Mitral stenosis-Mitral regurgitation -Mitral prolapse-Aortic stenosis-Aortic regurgitation