History
Symptoms of mitral stenosis usually manifest during the third or fourth decade of life and nearly half of the patients do not recall a history of acute rheumatic fever.
Patients are generally asymptomatic at rest during the early stage of the disease. However, factors that increase heart rate such as fever, severe anemia, thyrotoxicosis, exercise, excitement, pregnancy, and atrial fibrillation may result in dyspnea.
Nearly 15% of patients develop embolic episodes that are usually associated with atrial fibrillation. Rarely, embolic episodes may occur even in the patient with sinus rhythm. Systemic embolization may lead to stroke, renal failure, or myocardial infarction.
Hoarseness can develop from compression of the left recurrent laryngeal nerve against the pulmonary artery by the enlarged left atrium. Also, compression of bronchi by the enlarged left atrium can cause persistent cough.
Hemoptysis may occur and is usually not fatal.
Pregnant women with mild mitral stenosis may become symptomatic during their second trimester because of the increase in blood volume and cardiac output.
Physical Examination
The presence of mitral facies (pinkish-purple patches on the cheeks) indicate chronic severe mitral stenosis leading to reduced cardiac output and vasoconstriction.
Jugular vein distension may be seen. In the patient with sinus rhythm, a prominent a wave reflects increased right atrial pressure from pulmonary hypertension and right ventricular failure. A prominent v wave is seen with tricuspid regurgitation. The apical impulse may be laterally displaced or not palpable, especially in cases of severe mitral stenosis. This can be explained by decreased left ventricular filling. Rarely, a diastolic thrill can be felt at the apex with the patient in the left lateral recumbent position. See the videos below.
Often a right ventricular lift is palpable in the left parasternal region in the patient with pulmonary hypertension. A P2 may be palpable in the 2nd left intercostal space.
The auscultatory findings characteristic of mitral stenosis are a loud first heart sound, an opening snap, and a diastolic rumble.
The first heart sound is accentuated because of a wide closing excursion of the mitral leaflets. The degree of loudness of the first heart sound depends on the pliability of the mitral valve. The intensity of the first heart sound diminishes as the valve becomes more fibrotic, calcified, and thickened.
The second heart sound is normally split, and the pulmonic component is accentuated if pulmonary hypertension is present. The opening snap follows the second heart sound. The sudden tensing of the valve leaflets after they have completed their opening excursion causes an opening snap. In patients with elevated left atrial pressure and hence with severe mitral stenosis, the opening snap occurs closer to the second heart sound.
The diastolic murmur of mitral stenosis is of low pitch, rumbling in character, and best heard at the apex with the patient in the left lateral position. It commences after the opening snap of the mitral valve, and the duration of the murmur correlates with the severity of the stenosis. The murmur is accentuated by exercise, whereas it decreases with rest and Valsalva maneuver. In patients with sinus rhythm, the murmur increases in intensity during late diastole (so called, presystolic accentuation) due to increased flow across the stenotic mitral valve caused by atrial contraction.
A high-pitched decrescendo diastolic murmur secondary to pulmonary regurgitation (Graham Steell murmur) may be audible at the upper sternal border.
A pansystolic murmur of TR and an S3 originating from the right ventricle may be audible in the 4th left intercostal space in the patient with right ventricular dilatation.
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Mitral Stenosis. M-mode across the mitral valve showing a flat E-F slope resulting from elevated left atrial pressure throughout diastole due to a significant gradient across the mitral valve. Increased thickness and calcification of anterior leaflet of the mitral valve and decreased opening of the anterior and posterior leaflets in diastole are also shown.
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Mitral Stenosis. Parasternal long-axis view demonstrating calcification and doming in diastole of the anterior valve leaflet and mild restriction in the opening of posterior mitral valve leaflet.
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Mitral Stenosis. Apical 4-chamber view demonstrating restricted opening of the anterior and posterior mitral valve leaflet with diastolic doming of anterior leaflet with left atrial enlargement.
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Mitral Stenosis. Transesophageal echocardiogram with continuous wave Doppler interrogation across the mitral valve demonstrating an increased mean gradient of 16 mm Hg consistent with severe mitral stenosis.
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Mitral Stenosis. Apical 4-chamber view with color Doppler demonstrating aliasing in the atrial side of the mitral valve consistent with increased gradient across the valve. This figure also shows mitral regurgitation and left atrial enlargement.
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Mitral Stenosis. Magnified view of the mitral valve in apical 4-chamber view revealing restricted opening of both leaflets.
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Mitral Stenosis. Transesophageal echocardiogram in an apical 3-chamber view showing calcification and doming of the anterior mitral leaflet and restricted opening of both leaflets.
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Mitral Stenosis. Transesophageal echocardiogram in an apical 3-chamber view with color Doppler interrogation of the mitral valve revealing aliasing, which is consistent with increased gradient across the mitral valve secondary to stenosis. Also shown in this image, a posteriorly directed jet of severe mitral regurgitation.
Tables
- Table 1. Duration of Secondary Rheumatic Fever Prophylaxis
- Table 2. Secondary Prevention of Rheumatic Fever (Prevention of Recurrent Attacks)
- Table 3. Primary Prevention of Rheumatic Fever (Treatment of Streptococcal Tonsillopharyngitis*)
- Table 4. Recommendations for Mitral Stenosis (MS) Intervention
Category |
Duration After Last Attack |
Rating* |
|
Rheumatic fever with carditis and residual heart disease (persistent valvular disease† ) |
10 y or until age 40 y (whichever is longer); sometimes lifelong prophylaxis |
IC |
|
Rheumatic fever with carditis but no residual heart disease (no valvular disease† ) |
10 y or until age 21 y (whichever is longer) |
IC |
|
Rheumatic fever without carditis |
5 y or until age 21 y (whichever is longer) |
IC |
|
*Rating indicates classification of recommendation and level of evidence (eg, IC indicates Class I, level of Evidence C). †Clinical or echocardiographic evidence. |
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Agent |
Dose |
Mode |
Rating* |
Benzathine penicillin G |
Children 27 kg (60 lb): 600,000 U Patients >27 kg: 1,200,000 every 4 wk† |
Intramuscular |
IA |
Penicillin V |
250 mg bid |
Oral |
IB |
Sulfadiazine |
Children 27 kg: 0.5 g qd Patients >27 kg: 1 g qd |
Oral |
IB |
Macrolide or azalide (for individuals allergic to penicillin and sulfadiazine) |
Variable |
Oral |
IC |
*Rating indicates classification of recommendation and level of evidence (eg, IA indicates Class I, level of Evidence A). †In high-risk situations, administration every 3 weeks is justified and recommended. |
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Agent |
Dose |
Mode |
Duration |
Rating † |
Penicillins |
||||
Penicillin V (phenoxymethyl penicillin) |
Children 27 kg (60 lb): 250 mg bid or tid Patients >27 kg: 500 mg bid or tid |
Oral |
10 d |
IB |
Amoxicillin |
50 mg/kg qd (maximum 1 g) |
Oral |
10 d |
IB |
Benzathine penicillin G |
Children 27 kg (60 lb): 600,000 U Patients >27 kg: 1,200,000 U |
Intramuscular |
Once |
IB |
For individuals allergic to penicillin |
||||
Narrow-spectrum cephalosporin (cephalexin, cefadroxil) |
Variable |
Oral |
10 d |
IB |
Clindamycin |
20 mg/kg/d divided in 3 doses (maximum 1.8 g/d) |
Oral |
10 d |
IIaB |
Azithromycin |
12 mg/kg qd (maximum 500 mg) |
Oral |
5 d |
IIaB |
Clarithromycin |
15 mg/kg/d divided bid (maximum 250 mg bid) |
Oral |
10 d |
IIaB |
*Sulfonamides, trimethoprim, tetracyclines, and fluoroquinolones are not acceptable. †Rating indicates classification of recommendation and level of evidence (eg, IB indicates Class I, level of Evidence B) |
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Recommendation |
AHA/ACC (2014) [12] |
|
Concomitant mitral valve surgery for patients with severe MS (stage C or D) undergoing other cardiac surgery |
Class I |
|
Percutaneous mitral balloon commissurotomy (PMBC) for asymptomatic patients with very severe MS (stage C) and favorable valve morphology in the absence of left atrial (LA) thrombus or moderate-to-severe mitral regurgitation (MR) |
Class IIa: Reasonable |
|
PMBC for asymptomatic patients without unfavorable clinical characteristics when the risk of thromboembolism or hemodynamic decompensation is high |
Class IIa: Reasonable |
|
Mitral valve surgery for severely symptomatic patients (NYHA class III/IV) with severe MS (stage D), provided there are other operative indications |
Class IIa: Reasonable |
|
PMBC for asymptomatic patients with severe MS (stage C) and favorable valve morphology who have new onset of atrial fibrillation (AF) in the absence of an LA thrombus or moderate-to-severe MR |
Class IIb: Consider |
|
PMBC for symptomatic patients with a mitral valve area (MVA) above1.5 cm² if there is evidence of hemodynamically significant MS during exercise |
Class IIb: Consider |
|
PMBC for severely symptomatic patients (NYHA class III/IV) with severe MS (stage D) who have suboptimal valve anatomy and are not candidates or are at high risk for surgery |
Class IIb: Consider |
Class IIa: Reasonable |
Concomitant mitral valve surgery for patients with moderate MS undergoing cardiac surgery for other causes |
Class IIb: Consider |
|
Mitral valve surgery and excision of the LA appendage for patients with severe MS (stages C and D) who have had recurrent embolic events while receiving anticoagulation |
Class IIb: Consider |
