Mitral Stenosis. Etiology Most cases of mitral stenosis are due to rheumatic fever The rheumatic process causes immobility and thickening of the mitral.

Mitral Stenosis

Etiology

• Most cases of mitral stenosis are due to rheumatic fever

• The rheumatic process causes immobility and thickening of the mitral valve leaflets, with fusion of the commissures.

• Leaflet calcification and subvalvular fusion occur in the late stages of the disease.

PathophysiologyObstruction

Increased left atrial pressure Maintains LV Cardiac Output

Increased pulmonary venous and capillary pressures Exertional dyspnea

Reflex pulmonary arteriolarconstriction

Decreasing the amount of blood flowing through the lungs which lessens the likelihood of pulmonaryedemaPulmonary Hypertension

Right Ventricular Hypertrophy

RV Failure

Pathophysiology

• Atrial contraction is an important component of LV filling

• Loss of atrial contraction when atrial fibrillation develops results in about a 20% reduction in cardiac output

• The left ventricle is spared from both pressure and volume overwork in the pathophysiology of mitral valve obstruction

History

• Dyspnea, cough, and wheezing

• Hemoptysis

• Chest pain

• Thromboembolism

Physical Examination

• PMI of the LV is usually quiet

• Significant pulmonary hypertension may result in a left parasternal systolic lift indicating marked RV hypertrophy

Physical Examination

• Jugular Venous Pulse – a prominent a wave with pulmonary hypertension

• The arterial pulse is usually normal

Physical Examination

• S1 is accentuated due to the elevated LA pressure which does not allow the leaflets to float to a closed position

• S2 – the P2 component will become accentuated with pulmonary hypertension

S1 A2 P2S1 A2 P2

Physical Examination

• The Opening Snap• Occurs with the

abrupt cessation of movement of the mitral valve apparatus into the LV during early diastole

• Heard best at the apex and left sternal border

S1 S2 OS

Physical Examination

• The Murmur• A low pitched

rumbling diastolic murmur immediately following the OS

• Heard best at the apex

S1 S2 OS S1

Systole Diastole

Radiology

EKG

Echocardiography

Echocardiography

Cardiac Catheterization

Medical Management of Mitral Stenosis

• Subacute Bacterial Endocarditis Prophylaxis

• Diuretics

• Treatment of Arrhythmias– Digoxin– Anti-arrhythmic drugs

• Anticoagulation

When To Consider Surgical Management of Mitral Stenosis

• Usually there is a 15-20 year delay between an episode of rheumatic fever and the development of symptoms of MS

• The general indication for surgical intervention in chronic mitral stenosis is the presence of significant symptoms in spite of medical management

• Timing of intervention is based on numerous factors such as age of the patient, functional status, severity of the stenosis, and type of intervention

Interventional Management of Mitral Stenosis

• There are three general types of operative approaches in the treatment of mitral stenosis– Open Valvotomy - palliative therapy– Mitral Valve replacement– Balloon Valvuloplasty – palliative therapy

Balloon Valvuloplasty

Balloon Valvuloplasty

Mitral Regurgitation