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Mitral Valve Prolapse (MVP)


Guy P. Armstrong

, MD, Waitemata District Health Board and Waitemata Cardiology, Auckland

Reviewed/Revised Nov 2023
Topic Resources

Mitral valve prolapse (MVP) is a billowing of mitral valve leaflets into the left atrium during systole. The most common cause is idiopathic myxomatous degeneration. MVP is usually benign, but complications include mitral regurgitation, endocarditis, and chordal rupture. MVP is usually asymptomatic in the absence of significant regurgitation, although there are reports that some patients experience chest pain, dyspnea, dizziness, and palpitations. Signs include a crisp mid-systolic click, followed by a late systolic murmur if regurgitation is present. Diagnosis is by physical examination and echocardiography. Prognosis is excellent in the absence of significant regurgitation, but chordal rupture and endocarditis may occur. No specific treatment is necessary unless significant mitral regurgitation is present.

Mitral valve prolapse is common; prevalence is 2.4% in otherwise normal populations, depending on the echocardiographic criteria used (1 Reference Mitral valve prolapse (MVP) is a billowing of mitral valve leaflets into the left atrium during systole. The most common cause is idiopathic myxomatous degeneration. MVP is usually benign, but... read more Reference ). Females and males are affected equally; onset usually follows the adolescent growth spurt.


Etiology of Mitral Valve Prolapse

Mitral valve prolapse is most often caused by

  • Myxomatous degeneration of the mitral valve leaflets and chordae tendineae

In myxomatous degeneration, the fibrous collagen layer of the valve thins and mucoid (myxomatous) material accumulates. The chordae become longer and thinner and the valve leaflets enlarge and become rubbery. These changes result in floppy valve leaflets that can balloon back (prolapse) into the left atrium when the left ventricle contracts. Rupture of a degenerate chorda can allow part of the valve leaflet to flail into the atrium, which typically causes severe regurgitation.

Degeneration is usually idiopathic, although it may be inherited in an autosomal dominant or, rarely, in an X-linked recessive fashion. Myxomatous degeneration may also be caused by connective tissue disorders (eg, Marfan syndrome Marfan Syndrome Marfan syndrome consists of connective tissue anomalies resulting in ocular, skeletal, and cardiovascular abnormalities (eg, dilation of ascending aorta, which can lead to aortic dissection)... read more Marfan Syndrome , Ehlers-Danlos syndrome Ehlers-Danlos Syndromes Ehlers-Danlos syndromes are hereditary collagen disorders characterized by joint hypermobility, dermal hyperelasticity, and widespread tissue fragility. Diagnosis is clinical. Treatment is supportive... read more Ehlers-Danlos Syndromes , adult polycystic kidney disease Autosomal Dominant Polycystic Kidney Disease (ADPKD) Polycystic kidney disease (PKD) is a hereditary disorder of renal cyst formation causing gradual enlargement of both kidneys, sometimes with progression to renal failure. Almost all forms are... read more Autosomal Dominant Polycystic Kidney Disease (ADPKD) , osteogenesis imperfecta Osteogenesis Imperfecta Osteogenesis imperfecta is a hereditary collagen disorder causing diffuse abnormal fragility of bone and is sometimes accompanied by sensorineural hearing loss, blue sclerae, dentinogenesis... read more Osteogenesis Imperfecta , pseudoxanthoma elasticum Pseudoxanthoma Elasticum Pseudoxanthoma elasticum is a rare genetic disorder characterized by calcification of the elastic fibers of the skin, retina, and cardiovascular system. Diagnosis is clinical. There is no specific... read more Pseudoxanthoma Elasticum , systemic lupus erythematosus Systemic Lupus Erythematosus (SLE) Systemic lupus erythematosus is a chronic, multisystem, inflammatory disorder of autoimmune etiology, occurring predominantly in young women. Common manifestations may include arthralgias and... read more Systemic Lupus Erythematosus (SLE) , polyarteritis nodosa Polyarteritis Nodosa (PAN) Polyarteritis nodosa is a systemic necrotizing vasculitis that typically affects medium-sized muscular arteries and occasionally affects small muscular arteries, resulting in secondary tissue... read more ) and muscular dystrophies Introduction to Inherited Muscular Disorders Muscular dystrophies are inherited, progressive muscle disorders resulting from defects in one or more genes needed for normal muscle structure and function; dystrophic changes (eg, muscle fiber... read more . MVP is more common among patients with Graves disease Hyperthyroidism Hyperthyroidism is characterized by hypermetabolism and elevated serum levels of free thyroid hormones. Symptoms include palpitations, fatigue, weight loss, heat intolerance, anxiety, and tremor... read more Hyperthyroidism , hypomastia, von Willebrand disease Von Willebrand Disease Von Willebrand disease (VWD) is a hereditary quantitative deficiency or functional abnormality of von Willebrand factor (VWF), which causes platelet dysfunction. Bleeding tendency is usually... read more , sickle cell disease Sickle Cell Disease Sickle cell disease (a hemoglobinopathy) causes a chronic hemolytic anemia occurring almost exclusively in people with African ancestry. It is caused by homozygous inheritance of genes for hemoglobin... read more Sickle Cell Disease , and rheumatic heart disease Rheumatic Fever Rheumatic fever is a nonsuppurative, acute inflammatory complication of group A streptococcal pharyngeal infection, causing combinations of arthritis, carditis, subcutaneous nodules, erythema... read more Rheumatic Fever .

Myxomatous degeneration less commonly affects the aortic or tricuspid valve, resulting in aortic or tricuspid prolapse.

Mitral annular disjunction (MAD) is partial detachment of the mitral annulus from the ventricular myocardium, allowing for hypermobility of the mitral valve. MAD is strongly associated with mitral valve prolapse and ventricular arrhythmias Ventricular Fibrillation (VF) Ventricular fibrillation causes uncoordinated quivering of the ventricle with no useful contractions. It causes immediate syncope and death within minutes. Treatment is with cardiopulmonary... read more Ventricular Fibrillation (VF) . Identification of MAD can alter the surgical technique used for mitral valve repair.

Mitral regurgitation Mitral Regurgitation Mitral regurgitation (MR) is incompetency of the mitral valve causing flow from the left ventricle (LV) into the left atrium during ventricular systole. MR can be primary (common causes are... read more Mitral Regurgitation (MR) due to mitral valve prolapse may occur in patients with apparently normal mitral valve leaflets (ie, nonmyxomatous) due to ischemic papillary muscle dysfunction or rheumatic chordal rupture. Transient MVP may occur when intravascular volume decreases significantly, as occurs in severe dehydration or sometimes during pregnancy (when the woman is recumbent and the gravid uterus compresses the inferior vena cava, reducing venous return).


Ventricular ectopy commonly occurs in mitral valve prolapse. Severe ventricular arrhythmias or high ectopic burden occurs in < 10% of cases and is associated with sudden cardiac death.

Symptoms and Signs of Mitral Valve Prolapse

Most patients with mitral valve prolapse are asymptomatic. Some experience nonspecific symptoms (eg, chest pain, dyspnea, palpitations, dizziness, near syncope, migraines, anxiety) thought to be due to poorly defined associated abnormalities in adrenergic signaling and sensitivity rather than to mitral valve pathology. In about one third of patients, emotional stress precipitates palpitations, which may be a symptom of benign arrhythmias (atrial premature beats Atrial premature beats Various rhythms result from supraventricular foci (usually in the atria). Diagnosis is by electrocardiography. Many are asymptomatic and require no treatment. (See also Overview of Arrhythmias... read more Atrial premature beats , paroxysmal atrial tachycardia, ventricular premature beats Ventricular Premature Beats (VPB) Ventricular premature beats (VPB) are single ventricular impulses caused by reentry within the ventricle or abnormal automaticity of ventricular cells. They are extremely common in both healthy... read more Ventricular Premature Beats (VPB) , complex ventricular ectopy).

Other physical findings associated with but not diagnostic of MVP include hypomastia, pectus excavatum, hypokyphosis (eg, straight back syndrome), and a narrow anteroposterior chest diameter.


  • Crisp mid-systolic click

Typically, mitral valve prolapse causes no visible or palpable cardiac signs.

MVP alone often causes a crisp mid-systolic click as the subvalvular apparatus abruptly tightens. The click is heard best with the diaphragm of the stethoscope over the left apex when the patient is in the left lateral decubitus position. MVP with MR causes a click with a late-systolic MR murmur. The click moves closer to the first heart sound (S1) with maneuvers that decrease left ventricle (LV) size (eg, sitting, standing, Valsalva maneuver); the same maneuvers cause an MR murmur to appear or become louder and last longer. These effects occur because decreasing LV size causes papillary muscles and chordae tendineae to pull together more centrally beneath the valve, resulting in quicker, more forceful prolapse with earlier, more severe regurgitation. Conversely, squatting or isometric handgrip delays the S1 click and shortens the MR murmur.

The systolic click may be confused with the click of congenital aortic stenosis; the latter may be distinguished because it occurs very early in systole and does not move with postural or LV volume changes. Other findings include a systolic honk or whoop, thought to be caused by valvular leaflet vibration; these findings are usually transient and may vary with respiratory phase. An early diastolic opening snap caused by return of the prolapsed valve to its normal position is rarely heard. In some patients, especially children, the findings of MVP may be more noticeable after exertion.

Diagnosis of Mitral Valve Prolapse

  • Echocardiography

Diagnosis of mitral valve prolapse is suggested clinically and confirmed by echocardiography Echocardiography This photo shows a patient having echocardiography. This image shows all 4 cardiac chambers and the tricuspid and mitral valves. Echocardiography uses ultrasound waves to produce an image of... read more Echocardiography . Thickened ( 5 mm), redundant mitral valve leaflets are thought to indicate more extensive myxomatous degeneration and greater risk of endocarditis and mitral regurgitation.

Mitral annular disjunction is diagnosed echocardiographically when frame by frame analysis of the posterolateral annulus in the transthoracic parasternal long axis view reveals systolic separation of the annulus and ventricular myocardium by a few millimeters up to a centimeter.

Mitral annular disjunction increases the risk of sudden death from arrhythmia, and ambulatory cardiac rhythm monitoring is recommended.

Treatment of Mitral Valve Prolapse

  • Usually none

  • Sometimes beta-blockers

Mitral valve prolapse does not usually require treatment.

Beta-blockers (eg, atenolol, propranolol) and calcium channel blockers (eg, verapamil) decrease symptoms due to associated ectopy but there is no evidence that they improve prognosis.

Antibiotic prophylaxis against endocarditis is no longer recommended.

Anticoagulants to prevent thromboembolism are recommended only for patients with atrial fibrillation or prior transient ischemic attack or stroke.

Prognosis for Mitral Valve Prolapse

Mitral valve prolapse is usually benign, but severe myxomatous degeneration of the valve can lead to MR. In patients with severe MR, incidence of enlargement of the left ventricle or left atrium, arrhythmias (eg, atrial fibrillation), infective endocarditis, stroke, need for valve replacement, and death is about 2 to 4%/year. Men are less likely to have MVP, but those who do are more likely to progress to severe MR.

Key Points

  • Mitral valve prolapse is most often caused by idiopathic myxomatous degeneration of the mitral valve and chordae tendineae.

  • Mitral regurgitation (MR) is the most common complication.

  • Heart sounds often include a sharp, mid-systolic click that occurs earlier with the Valsalva maneuver.

  • Prognosis is usually benign unless MR develops, in which case there is increased risk of heart failure, atrial fibrillation, stroke, and infective endocarditis.

  • Treatment is not needed unless significant MR develops.

Drugs Mentioned In This Article

Drug Name Select Trade
HEMANGEOL, Inderal, Inderal LA, Inderal XL, InnoPran XL
Calan, Calan SR, Covera-HS, Isoptin, Isoptin SR, Verelan, Verelan PM
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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