Hereditary Heart Disease

• The main risk factors for heart disease are typically diabetes, high blood pressure, high cholesterol, smoking, lack of rest, and lack of physical activity. However, even in individuals who are in good health, who exercise regularly, and have no underlying conditions, heart disease can still be inherited.
• To detect inherited heart disease within families with a history of heart disease, it is recommended that those family members undergo genetic testing before any symptoms present. This helps assess the risk of having the disease and allows for appropriate care in the early stages. This proactive approach can help prevent the disease or alleviate severe symptoms, reducing the risk of sudden death caused by heart disease.

The term heart disease encompasses a broad range of conditions, which can be categorized into several groups, including diseases involving abnormalities in the heart muscle and/or valves, diseases involving abnormalities in the coronary arteries, diseases involving abnormalities in the heart’s electrical conduction system, and diseases involving abnormalities in the pericardium. Some types of heart disease may be present since birth, while others may develop later in life. The factors and risks that contribute to the development of heart disease include:

• Diabetes
• High blood pressure
• High cholesterol
• Chronic kidney disease
• Smoking

Various types of heart disease often occur without a known cause. However, one contributing factor to heart disease is genetic predisposition. Even individuals who appear healthy, who exercise regularly, and who have no apparent symptoms may still be susceptible to hereditary heart diseases.

It has been found that certain types of hereditary heart disease can occur in as many as 1 in 200 individuals in the general population. This relatively high prevalence underlines the potential loss of life posed by heart disease, even at a young age, and the possibility of transmission from parents to their offspring.

1. Cardiomyopathy
   Cardiomyopathy refers to both hypertrophic cardiomyopathy and dilated cardiomyopathy, which affect the ability of the heart muscle to relax and contract, resulting in reduced blood flow to the body. In some cases there may be abnormal thickening of the heart muscle causing insufficient blood circulation throughout the body and leading to heart failure and sudden death. Abnormal electrical conduction within the heart can also occur, causing symptoms such as palpitations, fainting, or even death. These conditions can occur in individuals who are otherwise healthy and have never experienced any prior symptoms.
2. Arrhythmia
   Arrhythmia can occur due to abnormal electrical impulses within the heart, causing an irregular heartbeat. The heart may beat too fast, too slow, or in an erratic pattern, affecting circulation to various parts of the body. This can lead to heart failure, blockage of cerebral blood vessels, or sudden death. Individuals with this condition may experience symptoms such as palpitations, dizziness, light-headedness, or chest pain.
3. Marfan Syndrome
   Marfan syndrome occurs due to abnormalities in connective tissues, which lead to excessive flexibility in various organs throughout the body. Complications that can arise include aortic aneurysm, which may result in aortic dissection that can potentially lead to death. Loose connective tissue in the heart valves can cause valve regurgitation, accompanied by severe fatigue, while other symptoms may include lens dislocation or lung collapse.
4. Coronary Artery Disease
   Coronary artery disease is caused by constricted or blocked coronary arteries, with common genetic risk factors including hereditary hypercholesterolemia causing the narrowing and blockage of blood vessels, even at a young age (under 45 for males and 55 for females). Individuals may experience symptoms such as chest pain and fatigue, both at rest and during exercise, and coronary artery disease can also cause instances of sudden or chronic heart failure, sudden low blood pressure, fainting, or cardiac arrest.
5. Aortic Dissection
   Aortic dissection causes rapid blood loss and sudden death, which is why it is considered extremely dangerous. It is mostly found in patients with poorly controlled hypertension, although it can also be caused by genetic mutations, such as in the case of the aforementioned Marfan syndrome. Typically, symptoms of the disease occur suddenly and intensely, with severe pains that start in the chest and spread to the patient’s back, and which can quickly lead to death if timely diagnosis and treatment are not carried out.

• Families with members who have the same type of heart disease in multiple generation.
• Family members of those who have died suddenly without a known cause.
• Family members of those who experience heart conditions such as ischemic heart disease or heart failure at a young age, for example, younger than 45 years old in males and younger than 55 years old in females.
• Family members of those who have been diagnosed with specific types of heart and coronary disease, including:
  • Hypertrophic cardiomyopathy
  • Dilated cardiomyopathy
  • Arrhythmogenic cardiomyopathy 
  • Brugada syndrome 
  • Long QT syndrome 
  • Premature atherosclerosis 
  • Marfan syndrome

• Inquiries into medical history and family history, particularly regarding heart diseases.
• Physical examination.
• If the doctor suspects that the patient may be at risk of an inherited heart disease, additional tests may be recommended. This may include genetic testing, which is done by collecting blood or other samples to extract genetic material or DNA. The process takes approximately 3-4 weeks, and the results will be explained to the patient by a specialized medical geneticist.

In cases where a genetic heart disease is detected, doctors will generally provide guidance regarding the disease itself, develop a treatment plan, and schedule regular follow-up examinations. Additionally, the doctor may recommend screening tests for family members to determine if they are at risk of the same type of heart disease. This may involve inquiring about symptoms, conducting physical examinations, and performing various laboratory tests, which may include genetic testing.

• It involves using personalized, in-depth analysis to effectively assess one’s genetic risk for inherited heart disease.
• It helps confirm the diagnosis of patients with inherited heart disease and enables the development of appropriate treatment strategies for both patients and their families.
• If a condition is detected early or at a young age, patients can prepare themselves to prevent or avoid the factors that may lead to abnormal symptoms or increased risk of disease progression.
• In cases where a patient is found to have genes associated with the risk of heart disease, the doctor can recommend that family members also undergo screening.

Undergoing genetic testing before experiencing any symptoms due to having family members with a heart disease and a suspicion of an inherited heart disease can provide information that is useful in assessing risk and planning timely treatment. This could help prevent the onset of the disease, alleviate severe symptoms, and prevent the risk of sudden death from heart disease.