Right ventricular hypertrophy refers to pathologically enhanced cardiac muscle of the right ventricle. While limited cardiac muscle strengthening within a cardiovascular exercise leads to an increase in cardiac performance, when cardiac muscle hypertrophy occurs, performance decreases again due to the increasing stiffness of the affected walls. In right heart hypertrophy, the pulmonary circulation, also called the small circulation, is affected.
What is right heart hypertrophy?
To some degree, myocardial strengthening of the entire heart, which can be achieved through cardiovascular exercise, results in increased performance. Only when the stimulus for growth of the myocardium of the right or left ventricle continues does right or left ventricular hypertrophy occur. Right ventricular hypertrophy is manifested by a pathological increase in the muscle tissue of the right ventricle. The heart wall in the area of the right ventricle is severely thickened and interspersed with fibrous tissue. As a result, the myocardium becomes inelastic and the capillary blood supply cannot fully follow the greater demand for oxygen, resulting in an additional oxygen deficiency in the smooth muscle cells of the myocardium. In right ventricular hypertrophy, the increasing stiffness of the heart muscle in conjunction with the oxygen deficiency supply leads to a reduction in the performance of the heart. The impaired ejection of the right ventricle first affects the pulmonary circulation, also called the small circulation, because blood from the right ventricle is pumped into the pulmonary artery through the open pulmonary valve during contraction (systole).
Causes
The most common cause for the development of right ventricular hypertrophy is left heart failure. Decreased ejection of the left ventricle, which pumps blood through the aortic valve into the great circulation or systemic circulation during systole, causes backpressure in the pulmonary circulation. The resulting increased pressure in the pulmonary artery triggers the stimulus in the right ventricle to increase pumping. However, since this does not solve the problem of backpressure, the right ventricle’s incentive to increase output persists and gradual hypertrophy sets in. Right ventricular hypertrophy may also be caused by partial obstruction of the lungs. Pulmonary emphysema, tuberculosis or diffuse pulmonary fibrosis, may lead to obstruction of part of the pulmonary circulation. This results in an increase in vascular resistance in the pulmonary artery, called pulmonary arterial hypertension. Similar to the congestion caused by left heart failure, the right ventricle initially responds with increased output, but this does not solve the problem. Hypertrophy therefore gradually develops. Other causes may include pulmonary valve stenosis or ventricular septal defect. In both cases, the right ventricle “tries” to compensate for the reduced supply to the aorta during systole by increasing its output, which then gradually triggers hypertrophy. A very rare cause is tetralogy of Fallot, a genetic maldevelopment of the heart. It is manifested by four defects occurring simultaneously: narrowing of the entrance to the pulmonary artery – comparable to pulmonary stenosis, incomplete closure of the cardiac septum between the two chambers, blocked aortic entrance and the resulting hypertrophy. Prolonged exposure to extreme altitude can also lead to right heart hypertrophy.
Symptoms, complaints, and signs
Incipient right ventricular hypertrophy is initially asymptomatic and symptomless. Only with decreasing ejection fraction of the right ventricle (diastolic dysfunction) do the first signs of shortness of breath on physical exertion appear. This is usually preceded by nonspecific, general fatigue and listlessness due to chronic oxygen deficiency (hypoxia). Blood stasis may develop in the digestive tract, leading to impaired digestion and decreased absorption capacity of nutrients in the small intestine. Impairments of certain liver functions may also develop. Externally visible signs are a greenish-blue discoloration of skin and mucous membrane areas (cyanosis). In some cases, accumulations of tissue fluid (edema) form and congestion occurs in the neck veins.
Diagnosis and course of the disease
Right heart hypertrophy can be detected by ultrasound examination (echocardiography). The ECG also allows conclusions to be drawn about the function of the heart. If necessary, magnetic resonance imaging (MRI) provides further findings and insights into the progress or severity of the disease. In more advanced stages, chest pain comparable to that of angina pectoris presents. Right ventricular hypertrophy can also trigger a cardiac arrhythmia or even cause a heart attack. The course of the disease increases in severity unless the cause of the hypertrophy is found or treated.
Complications
Right ventricular hypertrophy initially progresses without symptoms but is always associated with late complications. In the course of the disease, shortness of breath initially develops, which occurs predominantly during physical exertion and significantly limits the daily life of the affected person. The fatigue that typically occurs develops into physical exhaustion, which is also associated with restrictions in everyday life and work. Occasionally, blood congestion occurs in the digestive tract, resulting in impaired digestion and reduced absorption capacity of nutrients in the small intestine. In the long term, there is often also impairment of liver function associated with edema, cyanosis, and other symptoms. Treatment usually involves the use of diuretics, which may cause side effects. Possible complaints are dizziness, headache, muscle cramps and rash. In isolated cases, the drug promotes joint disorders such as gout, as well as impotence and menstrual cramps. If right heart hypertrophy is treated surgically, i.e. an artificial heart valve is inserted, this always places a great strain on the organism. Possible complications include atrial fibrillation, bleeding, infection, stroke and temporary psychological discomfort. In the case of undiagnosed pre-existing conditions, heart failure may also occur under certain circumstances.
When should you see a doctor?
Right ventricular hypertrophy should always be treated by a physician. There may be death of the affected person in the worst case with this disease if the right heart hypertrophy is not treated in time. The doctor should be consulted if severe breathing difficulties occur. These can occur especially in strenuous or stressful situations and have a very negative effect on the patient’s quality of life. Furthermore, severe shortness of breath also indicates right heart hypertrophy and should be investigated. Severe fatigue may also indicate the disease. It is not uncommon for patients to also suffer from impaired digestion and be unable to take in food and fluids without discomfort. In severe cases, right heart hypertrophy can also lead to cyanosis. In this case, an emergency physician should be called immediately or the hospital should be visited directly as well. In general, right heart hypertrophy is treated by a cardiologist. However, surgical intervention may also be necessary.
Treatment and therapy
The focus of a treatment and therapy for right heart hypertrophy is to treat the abnormality or disease that caused the hypertrophy. In many cases, this means reducing the elevated pulmonary pressure to remove the incentive for the right ventricle to compensate for the insufficient blood flow in the pulmonary artery. Diuretics can aid the process because they help to flush out accumulated tissue fluid via the kidneys in the case of edema or pulmonary emphysema, thereby decreasing central venous pressure. In other cases, where there is mitral valve or pulmonary valve insufficiency, implantation of an artificial heart valve may solve the problem.
Prevention
Preventive measures to prevent right heart hypertrophy can only ever lie in the prevention or prevention of disease states that have right heart hypertrophy as secondary damage. This means that the occurrence of non-specific complaints such as chronic fatigue, lack of physical performance and frequent blue discoloration of the lips and extremities should be clarified.If no clear cause or explanation for the symptoms is found, a cardiologic workup by ECG and echocardiography is also recommended in order to be able to take countermeasures as early as possible, preferably before the hypertrophy manifests.
Follow-up
In most cases, only limited measures of aftercare are available to the affected person for right ventricular hypertrophy, since it is a rare disease. If the disease has been present since birth, it usually cannot be completely cured. Therefore, if the affected person wishes to have children, he or she should have genetic testing and counseling to prevent the recurrence of the disease. There is usually no independent cure. Most of those affected are dependent on taking various medications, whereby attention must always be paid to the correct dosage and also to regular intake. In case of questions or uncertainties, a doctor should always be contacted first, and the doctor should also be consulted in case of side effects. Regular checks by a doctor are also very important. If the disease is treated by surgery, the affected person should take it easy after the procedure, especially protecting the affected region. This can prevent infections and inflammations. In many cases, right heart hypertrophy also limits the life expectancy of the affected person, although a general course cannot be predicted.
Here’s what you can do yourself
Patients with right heart hypertrophy should pay attention to the signs of their organism. Physical exertion or situations of overwork cause rapid fatigue as well as rapid exhaustion. The affected person should take breaks and completely avoid the onset of heavy exertion. Intensive sports activities should not be practiced. Leisure time activities should be adapted to the possibilities of the organism. Stress or emotional disturbing factors should be reduced at an early stage. It is helpful to practice relaxation techniques such as yoga or meditation. In addition, mental training sessions help to strengthen the mind. Conflicts with other people should be resolved as quickly as possible and should not be intensified. Cognitive techniques help to change one’s own behavior and avoid situations of confrontation with other people. In professional life, care must be taken not to exceed physical or mental limits. In everyday life, the patient must learn to respond to his own physical signals. Building up positive stimuli is important for promoting well-being and quality of life. Hobbies and leisure activities should be geared toward strengthening the patient’s zest for life. This reduces stress and supports good health. In addition, care should be taken to ensure that the body’s own weight is within the normal range of the BMI. Any excess weight should be reduced by changing and optimizing food intake.
