Definition

 Autoimmune disease (AD) is defined as the immune system attacking its own healthy cells, resulting in weakening and dysfunction of the immune system. They cause inflammatory syndromes due to various reasons, but commonly, gene alterations causing physiological effects are seen. Autoimmune diseases tend to overlap and as such, there is no specific gene responsible.

Autoimmune disease and the heart

Heart and autoimmune disease relation

• The structure of the heart is directly injured due to the long-term chronic inflammation caused by ADs
• Some ADs can be fatal leading to sudden death or cardiac arrest if symptoms are not visible or diagnosed early, especially in children and infants (e.g. Kawasaki disease, inflammation of medium-sized blood vessels)
• Heart damage due to ADs is irreversible; hence, early recognition, mainly during prenatal testing or post-natal testing, can help with the management and prevention of the disease

Affected heart structures in ADs include

• Endocardium - inflammation of the lining of heart valves and chambers causes endocarditis and valvular disease
• Myocardium - inflammation of heart muscle causes myocarditis and cardiomyopathy
• Pericardium - inflammation of sacs surrounding the heart wall causes pericarditis, and pericardial effusion
• Coronary arteries - ADs can cause acute coronary syndrome, ischemic heart disease

Heart dysfunction leads to cardiomegaly

• Myocardial collagen deposit - leads to disturbance in systolic and diastolic functions (how well the heart fills with blood and how well it pumps blood to the lungs and the body), this disturbance leads to gradual stiffening and fibrosis of the heart muscles
• Vascular endothelial dysfunction - narrowing of arteries can cause high blood pressure and chest pain, sometimes described as angina. A plaque can form within these vessels and eventually rupture which is a life-threatening emergency
• Coronary atherosclerosis - plaque builds up gradually, slowing the blood flow to the heart

Common autoimmune diseases associated with heart dysfunction 

Type 1 diabetes mellitus (T1DM) 

A condition where your body cannot make insulin resulting in hyperglycaemia (high blood sugar levels). Premature atherosclerosis, coronary artery calcium deposition, and damaged blood vessels are usually associated with altered heart function.

Grave’s disease 

A condition associated with overproduction of thyroid hormones which increase heart rate known as tachycardia. Over time if left untreated, this can lead to hypertension and cardiomyopathy.

Vasculitis

The immune system attacks blood vessels, causing inflammation, resulting in the narrowing of the arteries and veins, allowing less blood flow, impacting heart rate and causing physical symptoms such as palpitations.

Cardiopathy due to Churg-Strauss syndrome

Granulomatous vasculitis affects small and medium blood vessels, directly impacting the heart and also other vital organs due to reduced blood flow.

Takayasu disease 

A form of vasculitis that results in inflammation of large arteries and great vessels, mainly the aorta and its branches. Changes in lymphocyte infiltration cause erythrocyte sedimentation.

Polyarteritis nodosa

A condition resulting in severe inflammation and swelling of blood vessels. It often leads to vasospasm within the small blood vessels which reduces blood flow. 

Rheumatoid arthritis 

This inflammatory condition carries a high cardiovascular risk as it damages T and B lymphocytes, macrophages and dendritic cells, causing hyperplasia and angiogenesis that destroys cartilage and bones.

Sarcoidosis 

Granulomas can settle in various organs and disturb the normal functions, when they settle in the heart, it can lead to abnormalities like tachycardia and heart block. 

Diagnosis and symptoms

Common symptoms include

• Chest pain
• Shortness of breath 
• Oedema (swelling in limbs)
• Syncope (fainting)
• Heart palpitations 
• Fatigue

Diagnostic tests include

• Blood test
• Chest X Ray
• CT scan of heart and chest 
• Aortogram (specifically to check in through heart)
• ECG
• Cardiac catheterisation
• Myocardial biopsy

Risk factors and complications

• Use of alcohol for the long term
• History of heart failure and stroke
• Stressful routine
• Past treatment of radiation or chemotherapy
• BMI (body-mass-index) higher than 30

Treatment and prevention

Prevention

• Reducing stress levels through mindfulness techniques or CBT
• Regular exercise of about 30 minutes of moderate exercise every day to maintain a healthy weight and BMI
• Avoiding caffeine, alcohol and oily foods that can increase cholesterol
• Ensure you get a minimum of 8 hours of sleep daily

Medications usually prescribed

• Anticoagulants, antiarrhythmic drugs to lower cholesterol like statins
• Devices to regulate the heart’s function like pacemakers and ICDs
• Cardiac Re-synchronisation Therapy and Left Ventricular Assist Device target the pumping function of the heart to ensure that blood gets around to the vital organs 

FAQs

What are the causes of Cardiomyopathy?

History of autoimmune disease, stressful lifestyle, heavy lifting jobs, junk foods, mostly things that cause inflammation.

Which regular check-ups can maintain heart health problems?

Regular check-ups to monitor ECG, and lipid profile can help identify heart problems early on.

How is the life expectancy post-operatively of major heart surgery?

A person lives a full life, maintaining preventive measures and routine checkups.

What are the main factors responsible for heart disease?

High blood pressure and high cholesterol. 

What are the common symptoms seen in cardiovascular disease?

Dyspnoea, oedema, fatigue, and chest pain are some common symptoms.

 Can arthritis cause cardiac issues?

Yes, arthritis causes inflammation of the muscle and joints, directly affecting the heart muscle and cartilage.

Summary

Autoimmune disease is closely linked with heart pathologies however, there is no specific gene associated with this. Seeing a healthcare professional who will discuss your symptoms and medical history is key to getting tested. The common age of onset of autoimmune diseases is 20-30 years old however, there are some diseases specific to extremes of age such as Kawasaki disease in infants.