140 THE INDIAN JOURNAL OF PEDIATRICS

4. Hill HR, Quie PG. Raised serum IgE levels and defective neutrophil chemotaxis in three children with eczema and recurrent bacterial infection, l_aneet 1974; 1 : 183-197.

5. Van Scoy RE, Hill HR, Ritts RE, et al. Familial neutrophil chemotaxis defect, re- current bacterial infections, mucocutaneous candidiasis and hyper immunoglobulinemia E. Ann Inter Mefl 1975; 82: 766-771,

6. Hill HR, Williams PB, Kruger GG, et al. Recurrent staphylococcal abscesses associated with defective neutrophil chemotaxis and allergic rhinitis. Ann Intern Med 1976a; 85 : 39-43

7. Fontan G, Lorente F, Rodriguez MCG, et al. Defective neutrophil chemotaxis and

Vol. 54, No. 2

hyper immunoglobulinemia E, a reversible defect? Acta Pedlatr Seand 1976; 65 : 509-511

8. Blum R, Geller G, Fish LA. Recurrent severe staphylococcal infections, eczematoid rash extreme elevation of IgE, eosinophilia and divergent chemotactic responses in two gene- rations, d Pedtatr 1977; 90 : 607-609

9. Schopfer K, Baerlocher K, Price P, et al. Staphylococcal IgE antibodies, hyper immu- noglobulinemia E and Staphyloeoecxs a u r e u s

infections. N Engl J Med 1979; 300 : 835-838 10. Geha RS, Reinherz E, Leung D, et al. Defi-

ciency of suppressor T cells in the hyper immunoglobulinemia E syndrome. J Clim Invest 1981; 68:783-791

Mitral valve prolapse syndrome The term "mitral valve prolapse" has

been applied to describe the constellation of auscultatory findings, namely non- ejection systolic click and late systolic murmur with or without electrocardio- graphic changes. More recently charac- teristic echocardiographic findings have been described. Although mitral valve prolapse syndrome (MVPS) was described a century ago by Osler and others, 1-3 it is more widely recognised only during the last 25 years following the pioneering work of Barlow.4, 5 Although the mitral prolapse is found in association with many conditions, including atrial septal defect, ventricular septal defect, Marfan syndrome, Ehler-Danlos syndrome, homo- cystinuria, Kawasaki 's syndrome, Ebs- lein's anomaly of the tricuspid valve, L-transposition of the great arteries, coarctation of the aorta, cardiomyopathy and anomalous origin of the left coronary

artery f rom the pulmonary artery, it is most commonly seen as an isolated find- ing. The etiology of isolated MVPS is unknown. There are two major h y p o - theses. 6 The valvular theory which sug- gests myxomatous degeneration of the valve leaflet tissue as the principal cause and the myocardial theory suggesting primary regional or segmental myocar- diopathy causing abnormalities in the valve leaflets. The purpose of this pre- sentation is to highlight the current under- standing of the incidence, clinical features, laboratory findings and prognosis of isolaed MVPS.

Although the exact inc idence of MVPS in the pediatric population is not known, it appears to be in the order of 1-4~o, 7 much lower than that reported in adult populations (6.3%). The MVPS initially manifests with clinical symptoms in mid- childhood and early adolescence. 6 Higher

ANNOTATIONS 141

female to male preponderance (2 : I) repolted in adult patients appears to be preserved in the pediatric populations as well.6, s

In two-thirds of the patients, the MVPS is detected accidentally either on a routine physical examination or exami- nation during a non-specific febrile illness. 8 Non-specific ill-defined chest pain (18~), previous episode of rheumatic fever (7~), dysrhythmia (3~o) and chronic fatigue (3~o) were the complaints at the time of referral in the remaining patients. 8 Ner- vousness, emotional instability, palpita- tions, transient neurologic manifestations suggestive of cerebral embolism and syncope have also been reported as pre- senting symptoms.

Typical auscultatory .findings of apical non-ejection systolic click followed by late systolic murmurs is heard in over 60~ of the patients while isolated late systolic murmurs (24~) and isolated mid- systolic clicks (13~) may also be heard in some patients. Occasionally a holo- systolic type of murmur at the apex sug- gestive of mitral insufficiency may be heard. The murmurs may have "whoop- ing", "honking", "squeaking" or musical quality in 30~ of the patients. 8 The click is usually single but may be multiple on occasions. Variability of the auscultatory finding from time to time and with change in posture is characteristic of MVPS. Postural manoeuvres (lateral decubitus, sitting, standing), Valsalva and drugs (amyl nitrate) may be necessarY to induce typical auscultatory findings.

Chest roentgenograms are usually normal. Cardiomegaly may be present in patients with significant mitral insuffi- ciency. Thoracic cage abnormalities in- cluding pectus excavatum, straight-back

syndrome and thoracic scoliosis may be present in a significant number of patients.

Abnormal resting electrocardiograms are present in 50 to 60~o of patients with MVPS.6,s, 9 The abnormalities may vary from time to time. Ambulatory moni- toring may increase the incidence electro- cardiographic abnormalities. These can be divided into four major categories: abnormalities in repolarization, conduc- tion and rhythm and chamber hypertro- phy. Repolarisation disturbances usually consisting of inverted T waves in inferior leads and less frequently in left chest leads are the most common changes (21 to 48Uo). Conduction disturbances such as first- degree or second-degree (.rarely complete) heart block, left anterior hemiblock and right bundle branch block may be present in 10~ of the patients.6, s Arrhythmias in the form of atrial or ventricular (uni- focal or multifocal) premature contrac- tions, intermittent junctional rhythm, supraventricular tachycardia and occa- sionally ventricular tachycardia have been observed in 15~ of the patients;S most common among these is premature ven- tricular contractions. Chamber hyper- trophy consisting of left atrial, left ventri- cular or right ventricular hypetrophy may be present insome patients. Exercise testing has resulted in precipitating either ST-segment depression or unifocal PVCS in half of the patients tested, s In some patients, pre-existing premature beats disappeared with exercise.

Echocardiograms are useful in confir- ming the diagnosis of MVPS. However, false positive results can be produced by positioning tbe transducer too high and angulating it inferiorly and therefore, caution must be exercised to eliminate

142 THE INDIAN JOURNAL OF PEDIATRICS

artifactual mitral prolapse. M-mode echocardiographic criteria include dorsal movement of the posterior and/or anterior leaflet of the mitral valve of greater than 2 mm dorsal to an imaginary line drawn parallel to the chest wall from the C or closure point of the mitral valve echocar- diogram; pansystolic posterior hammo- cking or late systolic doral movement (Fig. 1) may be present, the latter by itself or in association with pansystolic abnor- mality is considered to be more reliable criteria than isolated pansystolic hammo- cking.10 Two dimensional echocardio- grams in long axis or four chamber views (Fig. 2) demonstrate sup.~rior displace- ment of posterior, anterior or both leaflets of the mitral valve superior to the atrio- ventricular junction11 and could be consi- dered to be more specific than M-mode findings in diagnosing the MVPS.

Left ventricular angiography in the right anterior oblique projection demons- trates movement of the mitral valve leaflets

Vol. 54, No. 2

into the left atrium during systole. This is best observed along the inferior margin of the mitral ring. The characteristic "ballerina-foot" contraction pattern of the left ventricle may be observed in some patients. 8 Although angiography may provide definitive diagnosis, it is not to be performed routinely because findings of physican examination and echocardio- graphy are sufficiently characteristic to establish the diagnosis.

Major but infrequent complications of MVPS include ventricular or supraven- tricular tachycardia, cerebrovascular ac- cidents, disabling chest pain, bacterial endocarditis and sudden unexpected death. Although there are no extensive long-term follow-up studies of MVPS in children it appears that this disease runs a relatively benign course in the pediatric population.

In summary, mitral prolapse in the pediatric populations appears to have a much lower incidence than in adults while

Fig. 1. M-mode echocardiogram showing mitral prolapse (arrows) in mid-systole. LV, left ventricle ; RV, right ventricle.

ANNOTATIONS 143

Fig. 2. 2-Dimensional echocardiographic frame from an apical four-chamber view demons- trating prolapse of the mitral valve (arrow) into the left atrium. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

maintaining the characteristic prepon- derence in females. It is detected on routine examination with only few presenting symptoms related to the cardiovascular system, exhibits typical auscultatory fea- tures of non-ejection systolic click followed

by late systolic murmur in 60~0 of patients, has characteristic features of M-mode and 2-dimensional echocardiography, and runs a benign course during childhood and adolescence. The etiology, more exact incidence and longterm natural history

144 THE INDIAN JOURNAL OF PEDIATRICS Vo 1.54, No. 2

o f MVPS in the pediatric populat ion are

yet to be clearly established.

P. Syamasundar Rao Consultant Pediatric Cardiologist,

Chairman, Department of Pediatrics, King Faisal Specialist Hospital

and Research Center, P.O. Box 3354 Riyadh 11211, Saudi Arabia

References

1. Osler W. On a remarkable heart murmur, heard at a distance from the chest wall. Can Med Surg J 1879-1880; 8 : 518~

2. Cuffer and Barbillon. Nouvelle recherches sur le bruit de galop. Arch Med Gen Trop 1887; 1 : 131-49, 301-20

3. Griffith JPC. Mid-systolic and late-systolic murmurs. Am J Med Sci 1892:104 : 285

4. Barlow JB, Pocock WA, Marchand P, Denny M. The significance of late systolic murmurs. Am Heart J 1963; 66:443

5. Barlow-JB, Bosman CK, Pocock WA, Marchand P. Late systolic murmur and non-ejection ("mid-late') systolic clicks: An

analysis of 90 patients. Br Heart J 1968; 30 : 203

6. Gingell RL, Vlad P. Mitral valve prolapse. In : Keith JD, Rowe RD, Vlad P, eds. Heart disease in infancy and childhood, 3rd ed. New York, Macmillan Publishing Co., Inc. 1978: 810-27

7. Lachman RD, Francheschi AD, Zamalloa O. Late systolic murmurs and clicks associa- ted with abnormal mitral valve ring. Am J Cardiol 1969; 23 : 679

8. Bisset GS, III, Schwartz DC, Meyer RA, James FW, Kaplan S. Clinical spectrum and long-term follow-up of isolated mitral valve prolapse in t19 children. Circulation 1980; 62 : 423-429.

9. Schmaltz AA, Ibraihm ZI, Apitz J. Clinical and anglo-and echocardiographic findings in 45 children with mitral valve prolapse synrodme. Europ J Cardioi 1978; 7:49-58

I0. Baylen BG, Criley JM. Diseases of mitral valve. I n : A d a m s FH, Emmanouiledes GC eds Moss' Heart disease in infants, children, and adolescents. 3rd ed. Baltimore, Williams & Wilkins, 1983 : 516-526

11. Goldberg SJ, Allen HD, Sahn DJ. Pediatric and adolescent echoeardiography. New York, Yearbook Medical Publishers, 1980 : 214-230.