Mitral valve prolapse in childhood: the incidence and clinical presentations in different age groups

Etiological Evaluation in Children Referred to the Pediatric Cardiology Outpatient Clinic with Chest Pain

Objectives

One of the most common reasons for pediatric cardiology referrals is chest pain in childhood. Although it is mostly innocent in character, it is rarely associated with life-threatening pathologies. In this study, it was aimed to evaluate the etiological causes in children with chest pain.

Methods

Our study included 1000 children who were referred to the pediatric cardiology clinic with the complaint of chest pain between January 2019 and June 2022. Demographic characteristics, accompanying complaints, echocardiographies, electrocardiographies, 24-h rhythm holters, treadmill exercise test, computed tomography angiography, and non-cardiac findings related to etiology were analyzed retrospectively from the file archives of the patients.

Results

Five hundred and nine (50.9%) of the patients were female and 491 (49.1%) were male. The mean age of the patients was 11.3 y (range: 3-18 years). Cardiological pathology associated with chest pain was detected in only 6.8% of the patients. Among the etiologies of chest pain, mitral valve prolapse (MVP) was the most common cardiological pathology with a rate of 2.1%. In the non-cardiac etiological evaluation of chest pain, idiopathic causes with a frequency of 48%, musculoskeletal pathologies with a frequency of 22.6%, respiratory pathologies with a frequency of 7.9%, psychiatric pathologies with a frequency of 7.3%, gastrointestinal pathologies with a frequency of 4.1%, and familial Mediterranean fever with a frequency of 2.4%, miscellaneous with a frequency of 1.1% were found, respectively.

Conclusion

In the study, it was determined that non-cardiac causes were more common among the etiological causes of chest pain in the pediatric age group. In addition, MVP was the most common cause of cardiac chest pain.

Echocardiographic screening for mitral valve prolapse in Turkish school children

We determined the frequency of mitral valve prolapse (MVP) in healthy Turkish school children using the current echocardiographic diagnostic criteria. This epidemiological survey was performed on 2550 school children. All children were screened with echocardiography and the family of children with MVP were also screened. The prolapse of mitral leaflets into left atrium ≥ 2 mm in parasternal long-axis view was used as diagnostic criteria. MVP was classified as classical or non-classical according to anterior mitral leaflet thickness. The thickness of anterior mitral leaflet, the extent of prolapse, and the presence of mitral regurgitation were evaluated. The children were also questioned about the associated symptoms. The prevalence of MVP was 1.25% in children with a mean age of 11.1 ± 2.9 years. The prevalence was 0.9%, 1.2%, and 1.6% in 5-9 years, 10-13 years, and 14-18 years of age, respectively. 43.7% of the cases were classical MVP. The frequency of auscultation findings was 34.3%. 11/34 children had mitral regurgitation. There was no statistically significant difference between classical MVP and non-classical MVP in terms of mitral regurgitation, physical examination findings, and symptoms. Anxiety (37.5%) was the most common symptom. The frequency of MVP in the first-degree relatives of children with MVP was 11/84 (13.1%). Most patients with MVP don't have auscultation findings and symptoms, therefore echocardiography is an important tool in the diagnosis of MVP. It is also reasonable to screen first degree relatives of MVP patients with echocardiography.

Chest pain in adult congenital heart disease: where does it come from?

Chest pain is common in adolescents and in young adults and usually not associated with a severe underlying cardiovascular disorder. However, in adults with congenital heart disease, residua or sequellae of previous interventions may provoke potential complications. Moreover, chest pain may be the first sign of a life-threatening condition. Basic knowledge is mandatory and will lead to the correct diagnosis and treatment. Data in literature, which focus on this issue, are scarce and motivated to summarize the experience of daily practice from the eye point of the clinician.

A prospective study to determine the significance of ventricular late potentials in children with mitral valvar prolapse

We aimed prospectively to determine the incidence of ventricular arrhythmias and ventricular late potentials in children with mitral valvar prolapse, and to assess whether signal-averaged electrocardiography could identify which such children were at high risk of developing ventricular tachycardia. In all, we examined 151 children with mitral valvar prolapse, at an age of 12.2 +/- 3.1 years, and 164 healthy subjects aged 12.3 +/- 3.7 years. All children underwent 24-hour ambulatory Holter monitoring and echocardiography. The children with mitral valvar prolapse were followed prospectively for a mean of 64 months. There was a significantly higher prevalence of ventricular arrhythmias in those with prolapse than in the controls (p < 0.0001). Runs of ventricular tachycardia were observed in 3 children with mitral valvar prolapse compared with one from the control group. Late potentials were more frequently observed in the children with mitral valvar prolapse than in those who were healthy (p < 0.0001), and also in those with prolapse suffering ventricular arrhythmias compared with those without ventricular arrhythmias (p < 0.02). During follow-up, 24 children with prolapsing mitral valves developed non-sustained ventricular tachycardia, giving a frequency of 3.1/100 subject-years. The sensitivity of late potentials was low, at 52%, for the identification of children with mitral valvar prolapse who developed ventricular tachycardia, although the specificity was high at 90%. This gave a positive predictive value of 50%, and a negative predictive value of 91%. We conclude that prolapse of the mitral valve predisposes to the development of ventricular arrhythmias and late potentials in children. An abnormal signal-averaged electrocardiogram is a specific, but not very sensitive, predictor for the development of ventricular tachycardia in such children.

Is mitral valve prolapse a manifestation of adolescent growth spurt?

The exact aetiology of mitral valve prolapse (MVP) is unknown, although this is the most common cardiac valvular abnormality currently detected. MVP has high incidence in young individuals, particularly during the second and third decades. These individuals are usually of a slender body habitus indicating higher rates of linear growth, reflective of the adolescent growth spurt. MVP might represent the imbalance in the growth dynamics of the mitral valve apparatus especially between the leaflets, chordae tendineae and the rest of the heart. Several reports suggest the transient nature of MVP and even complete disappearance. MVP with systolic click, but without a systolic murmur signifying regurgitation may be considered as a manifestation of adolescent growth spurt and a normal variant transiently occurring during particular periods of lives of otherwise normal individuals. Strategies of identification of subsets of individuals likely to harbor the more sinister and progressive form of MVP are important and need to be developed.

A germline mutation of the thyrotropin receptor gene associated with thyrotoxicosis and mitral valve prolapse in a Chinese family

Activating mutations of the TSH receptor (TSH-R) have been reported to result in toxic adenomas, multinodular goiters, sporadic neonatal hyperthyroidism, and familial autosomal dominant nonautoimmune hyperthyroidism. To date, all descriptions of such mutations, whether somatic or genomic, have been confined to the Caucasian population. We describe a Chinese family in whom a germline proline to serine substitution in position 639 resulted in familial thyrotoxicosis. This constitutively activating mutation has been previously described in a hyperfunctioning thyroid nodule. The three children in this family developed thyrotoxicosis during childhood; their father was diagnosed as thyrotoxic at the age of 38 yr. Two of the children and the father had mitral valve prolapse (MVP) associated with mitral regurgitation. There was a close temporal relationship between the onset of thyrotoxicosis and the diagnosis of mitral valvular disease in these patients. An increased prevalence of MVP has been reported in Graves' disease and chronic lymphocytic thyroiditis, but the pathophysiological mechanisms linking MVP and autoimmune thyroid disease are still not understood. This is the first report of an association between activating TSH-R mutations and MVP. We postulate that TSH-R activation may increase the clinical expression of MVP in genetically predisposed individuals.

Is mitral valve prolapse a congenital or acquired disease?

The prevalence of mitral valve prolapse (MVP) at birth was studied in 1,734 consecutive newborns without congenital structural heart disease. We have not identified any case of an unequivocal pattern of MVP using auscultatory and echocardiographic diagnostic criteria. Our data argue for the concept that MVP is an acquired disease.

Cost-effectiveness of echocardiography for evaluation of children with murmurs

Echocardiography is widely accepted as an accurate diagnostic test to evaluate heart murmurs in children, however its costs, and the ubiquity of murmurs in children, discourage its universal application. The purpose of this article is to identify some clinical circumstances in which the cost of echocardiography is justified for the evaluation of heart murmurs in infants and children. Eight common clinical problems were selected in which a heart murmur is present and a diagnosis is called for. Effectiveness of echocardiography and less costly clinical diagnostic methods in these settings were compared. In some circumstances, echocardiography is worth the cost, because clinical evaluation is unacceptably insensitive to important disease (the premature infant with a murmur which might represent a patent ductus arteriosus, the infant with a dysmorphic syndrome and a murmur). In others, the expert clinical examination is highly accurate (the asymptomatic child with a heart murmur) and is preferred over the echocardiogram as the initial diagnostic approach on the grounds of cost. When the expert clinical examination suggests minor structural heart disease, a continuum of echocardiographic cost-effectiveness relative to the expert clinical examination exists between these extremes depending on the working diagnosis. A threshold has not yet been defined at any point on this continuum above which the public will demand the greater diagnostic detail available echocardiographically, and below which the public will refuse to accept its greater cost. Quantitative formal cost-effectiveness analysis of echocardiography for evaluation of heart murmur in infants and children is not yet feasible because the benefits of echocardiography are indirect, dependent upon the as yet unmeasured benefits of correct management of congenital heart defects. To go beyond simple comparison of efficacy of echocardiography with less costly methods, further work is required in outcomes research in congenital heart disease.