Hypertrophic cardiomyopathy in children

Hypertrophic cardiomyopathy is a myocardial disease characterized by focal or diffuse myocardial hypertrophy of the left and / or right ventricle, more often asymmetric, involving the hypertrophic process of the interventricular septum, normal or reduced volume of the left ventricle, accompanied by normal or increased contractility of the myocardium with a significant decrease in diastolic function.

ICD-10 code

• 142.1. Obstructive hypertrophic cardiomyopathy.
• 142.2. Other hypertrophic cardiomyopathy.

Epidemiology

Hypertrophic cardiomyopathy is prevalent all over the world, but its exact frequency has not been established, which is associated with a significant number of asymptomatic cases. A prospective study by BJ Maron et al. (1995) showed that the prevalence of hypertrophic cardiomyopathy among young people (25-35 years) was 2 per 1000, and 6 out of 7 patients had no symptoms. In males, this disease is more common, both among adults and among children. Hypertrophic cardiomyopathy in children is found at any age. Diagnosis of it presents the greatest difficulties in children of the first year of life, their clinical manifestations of hypertrophic cardiomyopathy are not clearly expressed, they are often mistakenly regarded as symptoms of a heart disease of a different genesis.

Classification of hypertrophic cardiomyopathy

There are several classifications of hypertrophic cardiomyopathy. All of them are based on the clinical-anatomical principle and take into account the following parameters:

• a pressure gradient between the outflow tract of the left ventricle and the aorta;
• localization of hypertrophy;
• hemodynamic criteria;
• severity of the course of the disease.

In our country, the pediatric classification of hypertrophic cardiomyopathy was proposed by I.V. Leontief in 2002.

Working Classification of Hypertrophic Cardiomyopathy (Leontieva IV, 2002)

Type of hypertrophy	Severity of obstructive syndrome	Gradient of pressure, degree	Clinical stage
Asymmetric Symmetrical	Obstructive form Non-obstructive form	I degree - up to 30 mm II degree - from 30 to 60 mm III degree - more than 60 mm	Compensations Subcompensation Decompensation

Causes of hypertrophic cardiomyopathy

At the present stage of development of our knowledge, enough data has accumulated, suggesting that hypertrophic cardiomyopathy is a hereditary disease transmitted by an autosomal dominant type with various penetrance and expressiveness. Cases of the disease reveal in 54-67% of the parents and immediate relatives of the patient. The rest is the so-called sporadic form, in this case the patient does not have relatives who are ill with hypertrophic cardiomyopathy or who have hypertrophy of the myocardium. It is believed that the majority, if not all cases of sporadic hypertrophic cardiomyopathy also have a genetic cause, i.e. Are caused by random mutations.

Causes and pathogenesis of hypertrophic cardiomyopathy

Symptoms of hypertrophic cardiomyopathy

The clinical manifestations of hypertrophic cardiomyopathy are polymorphic and nonspecific, they range from asymptomatic forms to severe impairment of functional status and sudden death.

In children of early age, the detection of hypertrophic cardiomyopathy is often associated with the appearance of signs of congestive heart failure, which develops more often than in older children and adults.

Symptoms of hypertrophic cardiomyopathy

Diagnosis of hypertrophic cardiomyopathy

Diagnosis of hypertrophic cardiomyopathy is established on the basis of family history (cases of sudden death of relatives at a young age), complaints, results of physical examination. The information obtained through the instrumental survey is very important for establishing the diagnosis. The most valuable diagnostic methods are the ECG, which has not lost its importance at this time, and the two-dimensional Doppler echocardiography. In complex cases, differential diagnosis and clarification of the diagnosis are assisted by MRI and positron emission tomography. It is advisable to examine the relatives of the patient in order to identify family cases of the disease.

Diagnosis of hypertrophic cardiomyopathy

Treatment of hypertrophic cardiomyopathy

Treatment of hypertrophic cardiomyopathy in recent decades has not undergone significant changes and in essence remains largely symptomatic. Along with the use of various drugs, surgical correction of the disease is currently being carried out. Given that in recent years, the concept of the prognosis of hypertrophic cardiomyopathy has changed, the rationale for aggressive treatment tactics in most patients with hypertrophic cardiomyopathy raises doubts. When it is conducted, evaluation of the factors of sudden death is very important.

Symptomatic treatment of hypertrophic cardiomyopathy is aimed at reducing diastolic dysfunction, hyperdynamic function of the left ventricle and eliminating heart rhythm disturbances.

Treatment of hypertrophic cardiomyopathy

Forecast

According to recent studies based on extensive use of EchoCG and (especially) genetic studies of families of patients with hypertrophic cardiomyopathy, the clinical course of this disease is obviously more favorable than previously thought. Only in isolated cases the disease progresses rapidly, ending with a fatal outcome.

[1], [2], [3], [4], [5], [6]