What Heart Diseases Are Genetic? Conditions You Should Know About

Key Takeaways

• Not all heart conditions develop from lifestyle factors. Some are inherited and may affect heart structure, rhythm, or blood vessels from a young age.
• Genetic heart disease is assessed differently from acquired heart disease, with greater emphasis on family history, targeted testing, and long-term monitoring by a cardiologist.
• Early evaluation helps guide monitoring, activity advice, and long-term planning rather than immediate intervention.
• Knowing your inherited risk allows care to be tailored to how your heart is built and how it functions over time.

Heart disease is commonly linked to diet, exercise, and ageing, but this does not explain every diagnosis. Some people develop heart conditions despite staying active, eating well, or having no obvious risk factors. In these cases, the underlying cause may be genetic.

Genetic vs Acquired Heart Diseases: What Is the Difference?

Heart disease falls into two broad categories: genetic and acquired. Knowing the differences will help guide your approach.

Acquired Heart Diseases

Acquired heart diseases develop gradually over the course of an individual’s lifetime due to factors such as high blood pressure, high cholesterol, diabetes, smoking, or ageing. Coronary artery disease is a common example, where the narrowing of the heart arteries progresses over time.

Genetic Heart Conditions

Genetic heart disease typically arises from inherited gene changes that affect how the heart is built or how it functions. Although present from birth, symptoms may not appear until later in life. Moreover, they often occur in people without traditional cardiovascular risk factors. As such, doctors focus on identifying risk early, guiding safe activity levels, and monitoring changes over time. Family screening may also be advised to identify relatives who could benefit from evaluation.

Some individuals may have elements of both. A personalised assessment is needed to understand how inherited risk and lifestyle factors interact.

Common Types of Genetic Heart Disease

1. Inherited Cardiomyopathies (Heart Muscle and Structure)

Inherited cardiomyopathies involve abnormalities in the heart muscle that affect how blood is pumped around the body. These conditions may cause the heart muscle to thicken, stretch, or develop scarring, which can interfere with normal filling or contraction.

The major forms of cardiomyopathies include:

• Dilated Cardiomyopathy (DCM): The most common form of cardiomyopathy, with approximately 40% of familial cases linked to a genetic cause. Mutations in the TTN (titin) gene can lead to enlarged heart chambers and thinner muscle walls, reducing pumping strength.
• Hypertrophic Cardiomyopathy (HCM): Characterised by abnormal thickening of the heart muscle, usually affecting the left ventricle. In some cases, this thickening partially obstructs blood flow during exertion.

Both conditions may present with reduced exercise tolerance, chest discomfort, irregular heartbeat, and dizziness. A key distinction is that DCM more commonly causes progressive breathlessness, including paroxysmal nocturnal dyspnoea, where individuals wake suddenly at night struggling to breathe.

2. Inherited Channelopathies (Electrical System and Rhythm)

Inherited channelopathies affect the heart’s electrical signalling rather than its structure. The heart may appear normal on imaging, but rhythm disturbances can still occur.

Examples include:

• Long QT Syndrome (LQTS): Delayed electrical recovery after each heartbeat, with episodes often triggered by exercise, emotional stress, or sudden loud noises.
• Brugada Syndrome: Abnormal electrical conduction, typically during rest or sleep, which may present with fainting or unexplained collapse.
• Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT): Exercise- or stress-induced rhythm disturbances despite a normal resting heart rate and structure.

Due to the absence of structural changes, inherited channelopathies may not cause persistent symptoms or visible abnormalities on imaging. As a result, assessment relies on a detailed personal and family history of heart problems, electrocardiogram (ECG) test patterns, and rhythm monitoring rather than imaging alone.

3. Inherited Aortopathies (Major Blood Vessels)

Inherited aortopathies affect the strength of the aorta, the main artery carrying blood from the heart to the body. In conditions such as Marfan syndrome and Loeys–Dietz syndrome, connective tissue is weaker than normal, affecting not only the aorta but also areas such as the eyes, joints, and spine. More importantly, aortic changes may progress silently, with few or no symptoms, until enlargement becomes more severe.

For these conditions, regular echocardiography is commonly used to measure aortic size and assess how quickly it changes over time. In selected situations, additional imaging and computed tomography (CT) scans may be required to visualise segments of the aorta that are not well seen on ultrasound. A CT coronary angiogram may also be used when more detailed visualisation of the aorta or surrounding blood vessels is needed.

When to Seek Medical Advice

Many people with genetic heart disease feel well for long periods, but certain symptoms or situations should prompt medical review. Seeking advice early helps clarify whether further assessment or monitoring is needed, rather than waiting for symptoms to become disruptive.

You should consider seeking medical advice if you experience:

• New or worsening shortness of breath, especially during everyday activities or at night
• Chest discomfort, tightness, or unexplained fatigue during exertion
• Palpitations, a racing heartbeat, or irregular heart rhythm
• Dizziness, near-fainting, or fainting episodes, particularly during exercise or stress

You should also arrange for routine heart screening if:

• A close family member has been diagnosed with a genetic heart condition
• There is a family history of unexplained fainting, collapse, or sudden cardiac events at a young age

By identifying potential inherited heart conditions early, you can understand your personal risk more clearly, take appropriate precautions, and make informed choices about your health.

For individuals who have concerns about inherited risk, unclear test results, or whether family screening is appropriate, consult Dr Leslie Tay. He offers a range of screening options tailored to both individual and family needs and adopts a holistic approach to heart health and management. Make your first appointment today.