Mitral Stenosis

Etiology

Congenital

Epidemiology

Autoimmunity

-Less common and includes a wide range of anatomic variants

-In response to group A beta-hemolytic streptococcal M protein antigens
-Leads to inflammation and scarring of valvular leaflets
-Scarring causes leaflets to become fibrous and fused
-Chordae tendineae cordis becomes shortened

-Prevalence ~0.1% in the United States
-Rheumatic heart disease incidence in US has steeply declined over the past 4 decades (multifactorial reasons)
-Still major cause of cardiovascular disease in developing nations
-15.6 million people suffer from rheumatic heart disease world wide
-Approximately 282,000 new cases and 233,000 related deaths each year

Other Causes

-Infective endocarditis
-Systemic Lupus Erythematosus
-Rheumatoid arthritis
-Carcinoid heart disease
-Severe calcification of the mitral annulus

Mortality/Morbidity

-10 year survival rate in untreated patients ~ 50-60%
-Cause of death usually due to: cadiopulmonary failure (60-70%), systemic embolism (20-30%), pulmonary embolism (10%), & infection (1-5%)

Diagnosis

Physician assessment

-History
-Auscultation of murmur

Diagnostics

-Transthoracic echocardiogram
-12-lead electrocardiogram
-Chest Xray
-Tansesophageal echocardiogram

Treatment and Management

Diuretics

-Decrease preload
-Decrease pulmonary congestion

Anticoagulants

-Prevent blood clots in the presence of atrial arrhythmia

Beta blocker/Calcium channel blocker

-Slow heart rate
-Allow left ventricle fill more effectively

Antiarrhythmic

-Treat Atrial arrhythmia
-Increase cardiac output (when regular rhythm achieved)

Antibiotics

-To prevent reoccurence of rheumatic heart disease

Mitral valve repair

Surgical

-Open heart commissurotomy
-Tissue or mechanical valve

Non-surgical

-Balloon Valvuloplasty

Clinical Manifestations

Decreased Preload (decreased ventricular filling)

-Decreased cardiac output
-Fatigue (pronounced on exertion)
-Dizziness or fainting
-Headache

Left atrial hypertrophy

-Atrial enlargement
-Heart palpitations
-Atrial arrhythmia
-Chest discomfort or chestpain

Increased pulmonary vascular pressures


-Pulmonary congestion
-Pulmonary edema
-Coughing &Hemoptysis
-Dyspnea on exertion
-Orthopnea

Right sided heart failure

-Right Jugular venous distention
-Lower extremity edema
-Hepatic dysfunction
-Excessive fatigue
-Decreased appetite