Hypertrophic cardiomyopathy (HCM)

What’s that?

Myocardial hypertrophy is an increase in the heart wall’s thickness that develops under chronic overloading of the heart with increased pressure and/or large blood volume. The resulting structural and functional changes in the heart muscle disrupt the formation and conduction of the excitation impulse. This pathological phenomenon contributes to the development of cardiac arrhythmias. Most often, left ventricular myocardial hypertrophy develops. Among patients with this cardiologic pathology, there are people of all age categories.

About the disease

Hypertrophic cardiomyopathy (HCM) is a heart muscle disease characterized by massive thickening of one or more areas of the ventricular wall. In a person with HCM, the thickness of the free wall of the heart or, more commonly, the interventricular septum is more than 1.5 cm, whereas in the norm, it should not exceed 1 cm. To establish the diagnosis of myocardial hypertrophy, one important condition is the absence of heart valve defects or arterial hypertension (chronically elevated pressure) in the patient. In the adult population, this pathology is diagnosed in about 1 out of 500 people, with men among them 2-3 times more than women.

Types of hypertrophic cardiomyopathy

According to the localization of HCM, hypertrophic cardiomyopathy of the right and left ventricles is distinguished. The latter, in turn, is subdivided into two types:

asymmetrical, which is the most common;
symmetric (concentric), which accounts for approximately 30% of all clinical cases.

Taking into account the presence of a systolic pressure gradient in the left ventricular cavity, a distinction is made between LVHF with nonobstructive and obstructive components. Obstruction, appearing usually in the left ventricular outflow tract, is considered one of the possible clinical and morphologic manifestations of the pathology, as well as morphologic changes in the mitral valve apparatus and papillary muscles. The symmetric type of left ventricular hypertrophy is nonobstructive, while the asymmetric type may have both components.

Depending on the severity of myocardial thickening, hypertrophy is subdivided into:

moderate (1.5 to 2 centimeters);
medium (2.1-2.5 centimeters);
pronounced (exceeding 2.5 mm).

According to clinical and physiologic classification, four stages of HCM are distinguished.

The pressure gradient in the left ventricular outflow tract does not exceed 25 mmHg, and there are no clinical symptoms.
The pressure gradient increases to 36 mmHg, the person begins to feel negative changes in the general condition with physical activity.
The pressure gradient increases to 44 mmHg, there is dyspnea at rest, angina pectoris.
The pressure gradient exceeds 80 mmHg, there are pronounced disturbances in hemodynamics, sudden cardiac arrest is possible, and lethal outcome in the absence of emergency medical care.

Symptoms of left ventricular myocardial hypertrophy

The severity of symptoms depends on the stage of development of HCM. The pathology can progress over several decades, and if, at the first stages, a person is bothered only by minor discomfort, by the end of the disease, there is a severe threat to life.

In addition, cardiac pathology manifests itself differently depending on the cause of its development. In most cases, left ventricular myocardial hypertrophy is characterized by nonspecific signs:

pain in the chest area, radiating to the left arm and back;
intolerance to significant physical exertion;
late-stage fainting;
persistently elevated blood pressure;
marked shortness of breath;
angina;
arrhythmia.

General deterioration of the condition, attacks of weakness, dizziness, sleep disorders, experts explain the fact that the heart increased in size requires more oxygen than can be transferred to him respiratory organs and blood vessels.

Causes of left ventricular myocardial hypertrophy

The causes of HCM have a partial connection with genetic defects, so it can sometimes be inherited. The main prerequisites that can provoke the development of pathology include:

stress;
obesity;
aortic stenosis;
narrowing of the renal artery;
high blood pressure;
mitral valve dysfunction;
athletic heart with physiologic LV hypertrophy;
coarctation of the aorta, congenital narrowing of its separate parts;
infectious and somatic diseases of the respiratory system;
infiltrative cardiac processes (e.g., Danon’s disease, amyloidosis);
dilated cardiomyopathy is an acute enlargement of the heart cavities without thickening.

Diagnosis of left ventricular hypertrophy

Diagnostic measures are carried out mainly by instrumental methods to detect pathology and clarify the diagnosis. Laboratory studies on this disease are auxiliary. Examination includes:

collection of complaints and history;
auscultation;
measuring blood pressure and HR;
electrocardiography to clarify the degree of preservation of cardiac function;
echocardiography for early detection of the problem, determining the nature of the defect, and predicting the prospects for its progression.

Additionally, as indicated, may be prescribed:

isotope radiography;
Holter monitoring;
MRI;
aortic duplex scan.

If cardiovascular pathologies cannot be identified, the patient should undergo consultation and examination by an oncologist, geneticist, and endocrinologist. The participation of these specialists in the diagnosis allows confirmation or exclusion of extra-cardiac causes of pathology.

Treatment of left ventricular hypertrophy

There are two directions in the treatment of this pathology:

preventing the progression of the disease;
attempt at myocardial remodelling with a return to the thickness of the heart muscle and cavities to normal size.

Conservative therapy and surgical intervention may be used for this purpose.

Conservative treatment

In most cases, treatment of HCM should be accomplished by taking medications prescribed by the attending physician on a continuous, often lifelong basis. Medications have a cardioprotective effect (protect myocardial tissue from destruction) and stop the development of the primary disease. In the course of treatment, patients may be prescribed:

ACE inhibitors: according to numerous studies, this group of drugs effectively normalizes blood pressure and reduces LV wall thickness;
beta-blockers; these medications “relax” the myocardium, reduce heart rate, and reduce pre- and post-load on the heart;
nitrates; drugs from this group perfectly dilate blood vessels, which significantly reduces the load on the heart;
diuretics; they also reduce the load on the heart muscle, but they are prescribed mainly in the presence of concomitant cardiac pathologies in the patient and the development of chronic heart failure.

Surgical treatment of left ventricular myocardial hypertrophy

If drug therapy does not show results, surgical intervention is required. It is aimed at eliminating the deformations that led to the development of hypertrophy, as well as to eliminate directly excessive myocardium of the left ventricle:

aortic valve prosthesis: the operation consists of replacing a damaged aortic valve causing the development of left ventricular hypertrophy.
septal myectomy; during this procedure, the surgeon excises the hypertrophied part of the left ventricle, which helps to remove the obstruction of the outflow tract.

Before scheduling surgery, the physician assesses the balance of surgical necessity and contraindications.

All these treatment options are available in more than 660 hospitals worldwide (https://doctor.global/results/diseases/hypertrophic-cardiomyopathy-hcm). For example, septal myectomy can be done in 26 clinics across Turkey for an approximate price $14.4 K (https://doctor.global/results/asia/turkey/all-cities/all-specializations/procedures/septal-myectomy).

Prevention of left ventricular hypertrophy

The following principles are recommended to prevent myocardial hypertrophy:

avoiding bad habits;
avoiding excessive physical exertion;
normalization of blood pressure body weight;
a balanced diet with a reduction of animal fats in the diet;
regular visits to a cardiologist for screening tests.

Rehabilitation

After heart surgery, a full recovery period is necessary. The main recommendations are given to each patient by the attending physician before discharge. But there are also a number of general tips. These include:

adherence to a therapeutic diet;
decreased physical activity;
complete abstinence from alcohol and smoking;
increasing the amount of time spent outdoors.

Full rehabilitation will enable the patient to recover from the treatment much faster.