Pediatric Mitral Valve Prolapse


Background

Mitral valve prolapse (MVP), the most common anomaly of the mitral valve apparatus, occurs when one or both mitral valve leaflets excessively billows into the left atrium toward the end of systole. Mitral regurgitation (MR) develops in some patients with mitral valve prolapse, particularly those with more significant prolapse, when the valve edges fail to coapt. An extreme form of prolapse could include chordal rupture, in which the prolapsed mitral valve is flail. Mitral valves excised from patients with severe MR secondary to mitral valve prolapse have large leaflets and various histologic alterations.

Besides the symptoms attributable to the MR, various neuroendocrine and autonomic disturbances occur in some patients with mitral valve prolapse. In these patients, prolapse may be an epiphenomenon of the underlying autonomic or neurohumoral illness. The term mitral valve prolapse syndrome is often used to refer to the collection of these manifestations. However, in a significant proportion of patients, the mitral valve prolapse is trivial, and no such associated manifestations are present. In these patients, mitral valve prolapse constitutes an essentially benign condition.

Mitral valve prolapse syndrome was recognized as early as 1916, when Sir James MacKenzie described the soldier's heart in spare, thin young men with great vasomotor instability, easy fatigability, breathlessness, and pain over the region of the heart. Kerley first described the syndrome in 1920, and Lincoln described the syndrome in 1928. In 1963, Barlow and colleagues made the first clinical diagnosis of the syndrome as it is known today. The advent of echocardiography led to further advances and formed the basis of current knowledge.

Idiopathic mitral valve prolapse may be congenital in some patients, but recognition may be delayed until adolescence or adulthood. Associated complicating issues include cardiac arrhythmia, heart failure secondary to severe MR (rare), and, occasionally, thromboembolic events. Familial cases are known and occur in an autosomal dominant pattern with variable penetrance and expression (familial mitral valve prolapse).

Pathophysiology

Mitral valve prolapse (MVP) is a heterogeneous disorder and may originate from various underlying causes affecting one or more portions of the mitral valve leaflets, chordae tendineae, papillary muscle, and/or valve annulus. The syndrome may occur in isolation or in association with generalized connective tissue abnormalities, such as Marfan syndrome [1and Ehlers-Danlos syndrome, in which specific enzymatic defects are found. Mitral valve prolapse may occur in the context of inflammatory disease such as rheumatic fever or endocarditis. [2]

Isolated mitral valve prolapse can be sporadic or familial, demonstrating autosomal dominant and X-linked inheritance. Three different loci on chromosomes 16, 11, and 13 are linked to mitral valve prolapse, but no specific gene has been described. Another locus on chromosome X has also been found to cosegregate with a rare form of mitral valve prolapse called X-linked myxomatous valvular dystrophy. [3]

Isolated mitral valve prolapse has been independently associated with low body mass index; however, the reason for this association remains unexplained. [4]

Mitral valve prolapse may be secondary to rupture or dysfunction of the papillary muscles following myocardial infarction or ischemia, rupture of chordae tendineae due to infective endocarditis, or abnormal left ventricular wall motion in the setting of myocardial ischemia and/or primary myocardial disease. In these patients, the posterior leaflet in the floppy valve tends to have a significantly longer basal free-edge length and more frequent chordal rupture compared with patients with postinflammatory disease.

A connective tissue abnormality, possibly related to collagen metabolism, may underlie the idiopathic disorder. Abnormalities of collagen and elastic fibers have been documented in floppy mitral valves (FMV). Urokinase-plasminogen activator (PLAU), which is suggested in the pathogenesis of elastin and collagen degradation in arterial aneurysm, has also been implicated in mitral valve prolapse (PLAU T4065C TC genotype). TGFBR2 mutations have also been recognized among patients with mitral valve prolapse and Marfanlike phenotype. [5A Marfanlike phenotype A locus for autosomal dominant mitral valve prolapse has also been described on chromosome 11p15.4.

Investigators have also suggested that floppy mitral valve/mitral valve prolapse (FMV/MVP) syndrome may not be attributable alone to the severity of the mitral regurgitation (MR) and that hypersensitivity to adrenergic stimulation related to β1-adrenergic receptor polymorphism may play a partial role in symptoms, particularly in women with FMV/MVP. [6]

Electron microscopy of the affected valve leaflets shows a haphazard arrangement, disruption, and fragmentation of collagen fibrils. Myxomatous proliferation of the mitral valve, in which the middle spongiosa layer is predominantly involved, leads to the presence of unusually large amounts of myxomatous material and acid mucopolysaccharide. Degeneration of collagen within the central core of the chordae tendineae may lead to chordal rupture. Mitral valve prolapse can also follow rheumatic fever and myocardial infarction, in which case the prolapse is secondary to inflammatory or ischemic chordal rupture, respectively.

Metabolic and neuroendocrine abnormalities also occur in mitral valve prolapse and may separately result in prolapse unrelated to a connective tissue disorder. Adolescents with anorexia nervosa form a distinct group, in whom mitral valve prolapse develops as a result of reduced left ventricular filling. [7In such patients, increased norepinephrine and epinephrine may be found. Abnormalities in autonomic and neuroendocrine regulation have been demonstrated, including hyper-response to adrenergic stimulation, parasympathetic abnormalities (vagal withdrawal), altered baroreflex activity, renin-aldosterone regulation abnormalities, decreased intravascular volume, decreased left ventricular volume in upright posture, and atrial natriuretic factor secretion abnormalities.

Etiology

Heritable disorders of connective tissue include the following:

Skeletal abnormalities include the following:

Other diseases include the following:

Several reports suggest magnesium deficiency underlies the disease in some patients.

Epidemiology

United States data

Mitral valve prolapse (MVP) is the most prevalent cardiac valve disorder. Mitral valve prolapse is a common finding in otherwise healthy teenagers and young adults, particularly those patients who present with palpitations, chest pain, or dizziness. More than one third of cases in younger children are associated with other congenital heart defects. Reports vary, but 3-5% of pediatric patients likely have clinically significant mitral valve prolapse. However, a report from California places the prevalence at only 0.6%. [9]

International data

Prevalence rates are 1-2% in children and 5-15% in adolescents and young adults. In a series of 278 surgically removed mitral valves with pure regurgitation, mitral valve prolapse was present in 43%. [10]

Sex- and age-related demographics

Some studies show mitral valve prolapse is twice as frequent in females as in males.

Although findings are more frequent in older children and adults, the defect is believed to be present at birth.

Prognosis

Mitral valve prolapse (MVP) is not progressive in childhood, and specific therapy is not indicated for the vast majority of patients.

Progression to significant mitral regurgitation (MR) or sudden death is rare.

Asymptomatic patients with isolated mitral systolic clicks need only counseling and reassurance.

Morbidity/mortality

When present, associated abnormalities dictate the risk. Presence of significant MR and prolonged QT interval on ECG may also influence outcome. QT prolongation is slightly more prevalent among patients with mitral valve prolapse and may be associated with repolarization abnormalities and arrhythmia vulnerability. When severe, MR can lead to heart failure.

As noted above, mortality is rare in children. Sudden death is also rare and occurs more often in young women with a history of recurrent syncope, sustained supraventricular tachycardia, or complex ventricular tachycardia. Family history of cardiac sudden death often is a risk-stratifying indicator.

Development of MR and the progression of mild or moderate MR to severe MR are important determinants to morbidity. One study showed that the prevalence of MR increased from 29% of patients to 43% of patients during 4.3 years of follow-up. [11 Other possible complications include congestive cardiac failure, rupture of chordae tendineae, infective endocarditis (in 0.1-0.3 cases per 100 patient years), thromboembolic phenomena including cerebrovascular accidents, and sudden death. Cardiac arrhythmias such as ventricular tachycardia and ventricular fibrillation are more common in mitral valve prolapse.

Complications

Complications include the following:

  • MR: Progression or appearance of MR is one of the main complications. Over 4.3 years, approximately 14% of patients developed MR.

  • Congestive cardiac failure

  • Rupture of chordae tendineae

  • Infective endocarditis, in 0.1-0.3 cases per 100 patient years

  • Thromboembolic phenomena including cerebrovascular accidents and sudden death

  • Cardiac arrhythmia

  • Ventricular tachycardia and fibrillation

  • Syncope [12]

Patient Education

Note the following:

  • Careful explanation of the clinical findings and the nature of mitral valve prolapse (MVP) help to reassure the anxious patient.

  • Normal activity can be allowed if mitral regurgitation (MR) is not severe

  • Antibiotic prophylaxis during surgery and dental procedures is only necessary if associated MR is present.

  • The vast majority of patients with mitral valve prolapse remain asymptomatic for their entire lives and require observation every few years for reassurance.

  • Patients with orthostatic syncope secondary to dehydration should take extra salt and water during and following sport activities and competition.

  • Pregnancy requires infective endocarditis prophylaxis during delivery. Other implications are based on the severity of MR.

  • For patient education resources, see the Heart Health Center, as well as Mitral Valve Prolapse.

CLINICAL PRESENTATION

Physical Examination

Most patients are asymptomatic, and mitral valve prolapse (MVP) is an incidental auscultatory finding. Beta-blockers may markedly attenuate or abolish the symptoms, a fact that is important to remember while evaluating a patient who is receiving these agents. Findings are more marked when patients are examined in the outpatient department rather than in the inpatient setting, reflecting the contributory role of adrenergic state.

Chest pain

Chest pain occurs in 10% of patients diagnosed with mitral valve prolapse and may be caused by any of the following factors:

  • Excessive stretching of the chordae tendineae, leading to traction on papillary muscles

  • Coronary microembolism from platelet aggregates and fibrin deposits in the angle between the left atrium and the posterior mitral leaflet

  • Inappropriate tachycardia and excessive postural changes and physical and emotional stresses

  • Hyperadrenergic state, which increases myocardial oxygen demand

  • Coronary artery spasm

Palpitations

Palpitations are present in 7.4% of patients. The occurrence may be related to cardiac arrhythmia, although this has not been conclusively proven.

Fatigability and dyspnea

These often develop upon exertion. The cause may be alterations in centrally modulated breathing cycle control.

Neuropsychiatric

Panic attacks may occur. Nervousness, presyncope, and syncope occur in 0.9% of patients.

Thromboembolism, arrhythmia, or vasodepressor-vasovagal problems may be involved.

Pulse

Findings are usually normal. Pulse is occasionally irregular in the presence of premature contractions.

Exaggerated tachycardia (high-volume in severe mitral regurgitation [MR]) following exertion is not unusual.

Skeletal abnormalities

These are observed in two thirds of patients and do not fit into any of the recognized connective tissue disorders, although an occasional patient may have Marfan syndrome or other related syndromes. Common findings are as follows:

  • Hypomastia

  • Thin children

  • Height-to-weight ratio greater than normal

  • Arm span greater than height (dolichostenomelia)

  • Arachnodactyly

  • Scoliosis

  • Narrow anteroposterior chest diameter (straight back)

  • Pectus excavatum or pectus carinatum

  • Cathedral palate

  • Crowding of teeth

  • Joint hypermobility

Auscultation

Apical midsystolic nonejection click and late systolic murmur are the hallmarks, but either may occur alone.

The heart sounds are usually normal, but the first heart sound (S1) may be accentuated when prolapse occurs early in systole because of the summation of S1 and mitral click.

Multiple clicks occur when prolapse of different leaflets occurs at different times during the systole and may resemble pericardial friction rub.

In patients with redundant floppy mitral valves and significant MR, the murmur may be holosystolic and the click may be absent.

In cases in which the posterior mitral valve leaflet is prolapsing, the murmur may radiate along the left sternal border to the aortic area, thus mimicking left ventricular outflow tract murmur. If the anterior leaflet prolapses, the murmur radiates to the axilla and the spine.

Dynamic auscultation

In the sitting or standing position in late systole, the click may appear earlier and the murmur may be more prominent. The systolic click moves toward S1 upon standing, often merging with S1 if marked postural tachycardia occurs, and new clicks may appear. If an exaggerated heart rate response occurs, the murmur becomes longer and often louder to holosystolic. Occasionally the murmur is present only in the upright posture.

When squatting from standing position, the click and murmur may move back to late systole. Continuous auscultation, while the patient is standing from squatting position, reveals the click and murmur moving back to early systole on a beat-to-beat basis as the heart rate accelerates.

A systolic precordial honk or whooping sound may occasionally be heard with the murmur. Often these are heard only in the sitting or standing position and may be limited to a few beats immediately after standing.

Dynamic auscultatory changes reflect alterations in the timing of the mitral valve prolapse, the timing and extent of the MR, the expected changes in left ventricular volume, myocardial contractility, and heart rate. In the upright posture, venous return decreases, as does the left ventricular volume. The reflex tachycardia that occurs in the upright position further reduces left ventricular volume. Timing and degree of the prolapse are determined by the position of the mitral leaflets at end diastole, which, in turn, is dependent on the distance from the mitral valve annulus to the attachment of the chordae to papillary muscles. Low left ventricular end-diastolic volume shortens the mitral annular papillary muscle distance, allowing the leaflets to prolapse earlier in systole.

Prompt squatting from standing position increases venous return and left ventricular volume; thus, the systolic click and murmur may become late systolic. Squatting, however, may also be associated with an increase in peripheral vascular resistance, which, in turn, increases the tension on the mitral valve apparatus, preferentially directing blood flow into the left atrium, rather than to the peripheral circulation. The late systolic click and murmur then become accentuated in the squatting position.

Other maneuvers

Other maneuvers are possible but none is as practical as a systematically performed postural dynamic auscultation. These maneuvers include the following:

  • Leg elevation

  • Isometric hand grip exercise

  • Valsalva maneuver

  • Application of tourniquets to the extremities

  • Lower body negative pressure or amyl nitrate inhalation

DDx

Diagnostic Considerations

Important considerations

Note the following:

  • Do not fail to make the diagnosis

  • Do not fail to fully investigate patients who are symptomatic

  • Restrict exercise in patients who are symptomatic

  • Recognize the higher risk of arrhythmia during anesthesia and the perioperative period

  • Properly interpret findings: Patients with mitral valve prolapse (MVP) syndrome require a careful history and thorough physical examination because of the possibility of misinterpreting history, physical findings, borderline laboratory test results, and nonspecific electrocardiographic (ECG) or echocardiographic changes.

  • Avoid overtreatment

Special concerns

The diagnosis should include the type of prolapse (late systolic, holosystolic, anterior, or posterior leaflet), thickness of mitral valve leaflets, size of mitral annulus, and the left ventricular and left atrial size and function. The diagnosis should also include presence, severity, and timing of mitral regurgitation (MR); define jet direction and magnitude; and clearly list associated abnormalities.

Patients with orthostatic syncope secondary to dehydration should take excess salt and water during and following sport activities and competition.

Patients are more sensitive to volume depletion; hence chronic diuretic therapy should be avoided.

Other problems to be considered

Also consider the following conditions in patients with suspected mitral valve prolapse:

  • Congenital mitral regurgitation

  • Rheumatic mitral regurgitation

  • Tricuspid valve prolapse

Differential Diagnoses

Workup

Laboratory Studies

In patients with mitral valve prolapse (MVP), perform blood and other laboratory tests as dictated by the condition of the patient.

Other tests

Electrocardiography

Electrocardiography findings are usually normal; however, in about one half of children and adolescents, the findings may reveal inverted or biphasic T waves, especially in leads II, III, aVF, and/or V5-6 (see image below). [13The T-wave abnormalities may vary at different times in the same patient and may improve with exercise or with beta-blocker therapy.

Two-lead electrocardiogram of a child with mitral Two-lead electrocardiogram of a child with mitral valve prolapse (MVP) showing T-Wave inversion in leads III and aVF.

Arrhythmias described at rest or during exercise include premature atrial (23.6%) or ventricular (27.3%) contractions, supraventricular tachycardia, and conduction abnormalities. Patients with mitral valve prolapse demonstrate a higher frequency of left-sided accessory pathways. More serious findings include ventricular tachycardia and fibrillation.

A higher incidence of arrhythmia may be due to a prolonged QT interval. Diastolic depolarization of muscle fibers in the anterior mitral leaflet in response to stretch may also have a role.

Slow response action potentials originating in the atrial-like muscle fibers in the mitral valve leaflets can lead to sustained rhythmic action that penetrates the cardiac chambers.

Phonocardiography

This was previously used as an adjunct to confirm the auscultatory findings.

Imaging Studies

Radiography

Chest radiography findings are normal. Cardiac size and pulmonary venous congestion appear when mitral regurgitation (MR) is severe. The image below depicts a radiograph of a 5-year-old girl with mitral valve prolapse.

Chest radiograph of 5-year-old girl with mitral vaChest radiograph of 5-year-old girl with mitral valve prolapse (MVP) and mild mitral regurgitation. The radiograph shows cardiomegaly and normal pulmonary vasculature.

Skeletal surveys may reveal abnormalities. The image below depicts a radiograph of the left hand of a 10-year-old boy with marfanoid syndrome and mitral valve prolapse.

Plain radiograph of the left hand of a 10-year-oldPlain radiograph of the left hand of a 10-year-old boy with marfanoid syndrome and mitral valve prolapse (MVP) showing the long thin metacarpals. The metacarpal index is longer than normal.

Echo-Doppler ultrasonographic studies

This is an essential tool to identify the presence and magnitude of mitral valve prolapse. The thickness of mitral valve leaflets, mitral annulus size, chordae tendineae length, and left ventricular and left atrial size and function should be evaluated. The test also reveals any associated heart diseases. [14]

Multiple views of the mitral valve are essential, and the echo-Doppler findings have to be correlated with clinical data.

These studies, particularly transesophageal echocardiography in adults, also help identify potential embolic sources in patients with focal neurologic symptoms or signs.

Findings are always interpreted in the context of the clinical evaluation by dynamic auscultation. The diagnostic accuracy improves by use of a constellation of findings, which include structural and functional changes. Patients with echocardiographic criteria for mitral valve prolapse, without evidence of thickened redundant leaflets or significant MR, require careful review before mitral valve prolapse is diagnosed. Mere sagging of anterior leaflet in the 4-chamber view does not indicate mitral valve prolapse. Patients with typical auscultatory findings may be diagnosed even with questionable echocardiographic findings.

Rarely, patients with mitral valve prolapse may have typical echocardiographic findings but no abnormality on auscultation. Patients with suggestive symptoms and no auscultatory findings, who have nonspecific echocardiographic changes, present a real challenge and may require periodic reevaluation before a firm diagnosis can be made. Family history could be of help in some of these patients.

Two- and three-dimensional studies

Two-dimensional, real-time echocardiographic pictures from parasternal long-axis window reveal the mitral valve leaflets coming together in systole and billowing into the left atrium beyond the atrioventricular junction (see image below). The medial aspect of the anterior leaflet and middle scallop of the posterior leaflet are visualized from this view. The lateral scallop of posterior leaflet can be seen only from the apical 4-chamber window, and, at times, mitral valve prolapse can be focal.

The echocardiographic description of the mitral valve prolapse should include structural changes, such as leaflet thickening, redundancy, annular dilatation, and chordal elongation. A varying degree of noncoaptation of the leaflets is present, and MR can be identified by Doppler-color, pulse wave, and continuous wave. The MR jet can be defined, and its magnitude and direction estimated. The size of the left atrium and left ventricle are increased in the presence of moderate-to-severe MR.

Two-dimensional echocardiographic picture taken frTwo-dimensional echocardiographic picture taken from the parasternal long-axis view showing prolapse of both anterior and posterior mitral valve leaflets into the left atrium at systole.

Three-dimensional echocardiography is reportedly very helpful in delineating the prolapse and associated regurgitation (see image below). Segmental analysis of the mitral valve leaflets has been as successful with this technique as with transesophageal echocardiography. [151617It has also been reported to provide information that helps in surgical repair.

Color-Doppler echocardiography of a child with mitColor-Doppler echocardiography of a child with mitral valve prolapse showing jet of mitral regurgitation.

Transesophageal and M-mode studies

Transesophageal echocardiography has also improved the identification of leaflet morphology, assisting surgical repair.

M-mode echocardiography reveals a characteristic posterior movement of the posterior mitral leaflet during mid or late systole or pansystolic prolapse of both anterior and posterior mitral leaflets toward the left atrium (see image below). With the availability of 2-dimensional and Doppler studies, mitral valve prolapse should no longer be diagnosed solely on M-mode pictures.

M-mode echocardiographic picture of mitral valve pM-mode echocardiographic picture of mitral valve prolapse showing pansystolic prolapse of both anterior and posterior mitral leaflets toward left atrium.

Stress scintigraphy

Myocardial perfusion scintigraphy (eg, using thallium-201) during exercise may help identify the rare patient with mitral valve prolapse and myocardial ischemia.

Procedures

Ambulatory 24-hour electrocardiography

A Holter monitor may help identify the nature and frequency of arrhythmic activity in patients with mitral valve prolapse (MVP). Premature ventricular beats (38%), multiform couplets, and tachyarrhythmias (8%) are usual findings.

Exercise testing

This is useful in patients with palpitations and exercise-related symptoms. Premature ventricular beats (16%), ventricular tachycardia (4%), and supraventricular ectopy are common findings. Ventricular fibrillation is a rare finding.

Cardiac catheterization and angiography

These tests are generally restricted to patients with mitral valve prolapse and severe mitral regurgitation who may require valve repair or replacement. Associated coronary artery disease can also be confirmed or excluded.

A left ventricular angiogram, obtained in the right anterior oblique view, best shows the posterior leaflet. A left anterior oblique projection reveals the anterior leaflet.

Other abnormalities that may be revealed include dilatation, decreased systolic contraction, calcification of the mitral annulus, and poor contraction of the basal portion of the left ventricle.

Electrophysiology

Indications for electrophysiology (EPS) are similar to those in general clinical practice. EPS is useful in the presence of supraventricular tachycardia because accessory atrioventricular pathways are common in patients with mitral valve prolapse. In this subset of patients, EPS is important because radiofrequency ablation can be performed during the same procedure, with a very high curative success rate.

Tilt test

Upright tilt studies with blood pressure and cardiac rhythm monitoring may be valuable in patients with light-headedness or syncope when vasodepressor-vasovagal reaction is suspected and confirmation of clinical symptoms is desired.

Histologic Findings

Mitral valves excised from patients with severe mitral regurgitation (MR) secondary to mitral valve prolapse (MVP) have large leaflets and show various alterations.

The most specific, fundamental, and characteristic histologic changes are (1) collagen dissolution and disruption in the pars fibrosa of the mitral valve leaflet and (2) replacement of the dense collagenous fibrosa by loose myxomatous connective tissue with high acid mucopolysaccharide content. Similar histologic abnormalities are observed in chordae tendineae.

Scanning electron photomicrographs demonstrate surface folds and focal loss of endothelial cells on mitral valve leaflets obtained from patients with severe mitral valve prolapse and significant MR. These surface abnormalities may predispose to thromboembolic complications and/or infectious endocarditis.

Continuous pressure and stress on the leaflets and chordae tendineae during left ventricular systole contribute to gradual progression of these histologic changes.

TREATMENT AND MANAGEMENT


Medical Care

Admission of patients with mitral valve prolapse (MVP) is seldom required, except in the case of complications or for consideration of surgical intervention.

In childhood, MVP is not progressive, and specific therapy is not indicated for the vast majority of patients. Asymptomatic patients with isolated mitral systolic clicks need only counseling and reassurance. Clinical and echocardiographic follow-up every 2-5 years may be appropriate.

Avoid excessive use of caffeine, cigarettes, alcohol, and prescription or over-the-counter drugs that contain stimulants such as epinephrine or ephedrine to minimize catecholamine and cyclic adenosine monophosphate (AMP) stimulation. Prevention of volume depletion before, during, and immediately after exercise may help. Subacute bacterial endocarditis antibiotic prophylaxis coverage for at-risk procedures is indicated in patients with mitral valve prolapse and mitral regurgitation (MR); however, the recommendations have undergone major changes. See Antibiotic Prophylactic Regimens for Endocarditis. [18]

Additional dental care recommended for patients at risk for infective endocarditis includes the following:

  • Regular tooth brushing after eating

  • No cookies, sweets, or sweet drinks between meals

  • Regular dental checks every 6 months

  • Fluoride supplements in locations where the fluoride in drinking water is less than 0.3 ppm for children younger than 2 years or less than 0.7 ppm for children younger than 2 years

  • Dental treatments (more than 2) scheduled at an interval of 14 days or longer

Surgical Care

Relatively recent advances have made reconstructive mitral valve surgery feasible in patients with congestive heart failure, severe mitral regurgitation (MR) secondary to mitral valve prolapse, or both. [192021 Some surgeons advocate robotic mitral valve repair because it is a less invasive approch with good results. [22]

Some surgeons have adopted a simplified mitral valve repair in pediatric patients with connective tissue disorders and severe MR associated with bileaflet prolapse. [23In a retrospective (2000-2014) of 18 children (< 18 years old) with these conditions at 3 institutions treated with ring annuloplasty and Alfieri edge-to-edge repair, at median 2.4 year follow-up, 1 child died (5.6%) whereas the remaining 17 children (94.4%) had mild regurgitation or less, no stenosis or systolic anterior motion, and regression of left ventricular enlargement. Aside from the single death, no other major complications were noted. [23]

In a retrospective study (1993-2013) of 4477 children who underwent mitral valve surgery to evaluate whether surgical correction of bileaflet valve alone reduces the incidence of ventricular dysrhythmias, 5 of 8 children who had bileaflet mitral valve prolapse, a presurgical malignant ventricular arrhythmia, and an internal cardioverter-defibrillator (ICD) in place before and after surgery showed a postsurgical reduction of malignant arrythmia (ventricular fibrillation, ventricular tachycardia) and appropriate ICD shocks. [24]

For details of surgical intervention, results, postoperative care, and complications of MR, see Mitral Regurgitation.

Consultations

A multidisciplinary approach is preferable, including the following consultation with the following specialists:

  • Pediatrician

  • Pediatric cardiologist

  • Radiologist

  • Geneticist

  • Cardiothoracic specialist

  • Physiotherapist

  • Family medicine specialist

  • Orthopedist

Activity

A gradual return to exercise may be tolerated. In the absence of studies on the effect of exercise on the progression of mitral valve prolapse (MVP), the best approach at present is based on common sense and good clinical judgment.

Patients with symptoms of syncope, presyncope, or palpitations upon exertion should undergo thorough evaluations and avoid competitive sports for at least 6 months after the last significant episode. In the presence of significant mitral regurgitation (MR), limitations apply as for any other cause of MR.

Coexisting aortic root dilatation and aortic regurgitation can further limit activity.

Patients with cardiac arrhythmia should have periodic exercise tests performed and ambulatory electrocardiographic (ECG) recordings obtained while doing the type of exercise they are likely to undertake.

Sudden death is extremely uncommon in mitral valve prolapse.

Long-Term Monitoring

Patients with mitral valve prolapse (MVP) require continued follow-up care and evaluation into adult life. Note the following:

  • Repeat evaluations every 2-5 years to identify any progression.

  • Infective endocarditis prophylaxis is indicated in patients with mitral valve prolapse and mitral regurgitation (MR) while undergoing at-risk procedures. However, these recommendations have undergone major changes. For more information, see  Antibiotic Prophylactic Regimens for Endocarditis.

  • Patients with accessory pathways should have detailed electrophysiology studies and radiofrequency ablation of the accessory pathway.

  • Coronary artery anomalies should be excluded in patients with chest pain before they participate in sports.

  • Mild prolapse on echocardiography, in the absence of clinical findings (15-20% of patients), does not indicate true mitral valve prolapse syndrome. Parents and patients need to be reassured.

MEDICATION

Medication Summary

Medical strategies for mitral valve prolapse (MVP) include the following:

  • Anticongestive heart failure therapy

  • Antibiotic therapy for endocarditis prophylaxis during surgery, dental, and genitourinary procedures: Only necessary if associated mitral regurgitation is present (See Antibiotic Prophylactic Regimens for Endocarditis.) [18]

  • Antiarrhythmic therapy: May be indicated in patients with documented and/or symptomatic arrhythmia, depending on findings of noninvasive and/or invasive electrophysiologic testing

  • Beta-blockers (eg, propranolol): May be beneficial for symptom prevention, reduction in ectopy, treatment of vasodepressor syncope, panic attacks, or antiarrhythmic therapy [25]

  • Antiplatelet therapy (eg, aspirin, dipyridamole): Used in patients with thromboembolic episodes

  • Angiotensin-converting enzymne (ACE) inhibitors:- Used in patients with significant mitral regurgitation

  • Low-dose aspirin and/or anticoagulant therapy (eg, warfarin): Considered in patients with thromboembolic episodes

Beta-adrenergic blocking agents

Class Summary

These agents block the beta-adrenergic receptor and are modulators of the autonomic system. They inhibit chronotropic, inotropic and vasodilatory responses to beta-adrenergic stimulation.

Propranolol (Inderal)

Inhibits beta1-adrenergic and beta2-adrenergic receptors. Class II antiarrhythmic, nonselective, beta-adrenergic receptor blocker with membrane-stabilizing activity that decreases automaticity of contractions.

Antiplatelet agents

Class Summary

These drugs are used for secondary prevention of thrombotic cerebrovascular or cardiac disease.

Aspirin (Anacin, Bayer, Empirin)

Inhibits prostaglandin synthesis, which prevents formation of platelet-aggregating thromboxane A2.

Dipyridamole (Persantine)

Acts by decreasing platelet aggregation. Inhibits thrombus formation in the arterial side of circulation.

Diuretics

Class Summary

These drugs are used to release retained fluid and lower preload.

Furosemide (Lasix)

Inhibits reabsorption of fluid from ascending limb of the Henle loop in renal tubule. Administered IV. Has venodilation action; thus, also lowers preload even before diuresis effect. Useful in acute heart failure and exacerbations of chronic heart failure.

Spironolactone (Aldactone)

Potassium-sparing diuretic. Acts on the distal convoluted tubule of the kidney as an aldosterone antagonist. Has synergistic action with furosemide.

Amiloride (Midamor)

Pyrazine-carbonyl-guanidine unrelated chemically to other known antikaliuretic or diuretic agents. Potassium-conserving (antikaliuretic) drug that, compared with thiazide diuretics, possesses weak natriuretic, diuretic, and antihypertensive activity. Acts directly on the distal renal tubule, usually used along with a potassium-losing diuretic.

ACE inhibitors

Class Summary

These agents reduce afterload and decrease myocardial remodeling, which worsens chronic heart failure.

Captopril (Capoten)

Accepted as essential part of heart failure therapy. Not only gives symptomatic improvement but also prolongs survival.

Cardiac glycoside

Class Summary

These agents provide symptomatic improvement in heart failure.

Digoxin (Lanoxin)

Improves myocardial contractility, reduces heart rate, and lowers sympathetic stimulation in chronic heart failure.