Congenital Heart Disease

Congenital heart disease (CHD) is one of the most common birth defects, affecting millions of individuals worldwide. It refers to structural abnormalities in the heart present from birth, which can range from mild to severe. Medical advancements over the years have continuously improved the diagnosis and treatment of congenital heart disease (CHD) and have given many an opportunity to live normal, healthy, and fulfilled lives. This blog is an introduction to Congenital Heart Disease that covers its causes, symptoms, treatment modalities, and general prognosis.

Congenital Heart Diseases Risk Factors and Causes

Although pinpointing the exact cause of CHD is not always possible, several known factors contribute to its development.

Parental Health Conditions

 When congenital heart defects are present among the parents or close relatives, the chance of the child being born with congenital heart defects is increased.

• Diabetes: Both a mother’s pre-existing and gestational diabetes put an unborn child at increased risk for CHD. 
• Infections: Infections while pregnant are a serious threat. 
• Autoimmune Diseases: Some autoimmune diseases, including lupus, increase the risk of cardiovascular disease. 
• Unhealthy Lifestyle Choices: The choices made while pregnant have significant effects on the mother and the developing fetus and thereby trigger risk.

Environmental Factors

Exposure to other environmental toxins during pregnancy and harmful substances can interfere with the complex processes involved in heart development in the fetus. 

• Alcohol and Tobacco: Maternal alcohol and tobacco consumption during pregnancy is a known teratogen, increasing the risk of CHD.
• Medications: Some medications can increase the risk.
• Exposure to Chemicals: Exposure to certain kinds of chemicals, such as solvents or pesticides, during pregnancy may increase the risk of CHD.

Chromosomal Abnormalities

Syndromes such as Down syndrome, Turner syndrome, and DiGeorge syndrome are often associated with CHD.

Symptoms of Congenital Heart Disease

Some infants and children may present with overt symptoms shortly after birth, while others may remain asymptomatic for a period, with symptoms gradually emerging later in life.

Common Symptoms in Infants and Children:

Common symptoms in infants and children include:

• Rapid Breathing or Difficulty Breathing (Dyspnea): Pumping of the blood is ineffective by the heart, which causes shortness of breath, especially during feeding or activity.
• Cyanosis (bluish skin due to low oxygen levels): The bluish discolouration that is prominent on the lips, skin, and nail beds is evidence that the saturation of oxygen in the blood is low. 
• Poor Weight Gain or Difficulty Feeding: Infants with CHD often struggle to gain weight adequately. Feeding can be tiring, leading to inadequate intake.
• Swelling (Edema): It occurs in the legs, abdomen (ascites), or around the eyes. 
• Excessive Fatigue: It happens particularly during feeding or activity. 
• Heart Murmurs: It is detected during routine checkups: A heart murmur is an abnormal sound produced within the heart by turbulent blood flow. 
• Frequent Respiratory Infections: Children with CHD may be more prone to pneumonia and other respiratory infections.

Congenital Heart Disease Symptoms in Adults

Common symptoms in adults include:

• Shortness of Breath: It can occur particularly during physical activity
• Fatigue: Fatigue and low energy levels
• Arrhythmias (irregular heartbeats): Arrhythmias can lead to palpitations, dizziness, or fainting.
• Dizziness or Fainting Episodes (Syncope): These episodes can occur when the heart is unable to maintain adequate blood flow to the brain.
• High Blood Pressure: High blood pressure and chest pain can develop because of the strain on the heart.
• Swelling (edema): It happens in the legs, ankles, or abdomen
• Exercise Intolerance: The individual may find it difficult to perform activities that require physical exertion.
• Cyanosis: While less common in adults, some individuals with certain types of CHD may exhibit cyanosis.

Types of Congenital Heart Disease

Knowledge of the classification of Congenital heart diseases helps to understand the pathology itself and the guiding therapies.

Cyanotic Congenital Heart Diseases

These defects are characterised by lower oxygen levels in the blood (hypoxemia), clinically resulting in cyanosis (blueness). In these defects, either the blood bypasses the lungs or mixes with the deoxygenated blood. Commonly known forms of cyanotic congenital heart defects include the following:

• Tetralogy of Fallot (TOF): This is a complex type of defect with the following four major abnormalities:
• Transposition of the Great Arteries (TGA): In this condition, the aorta is in front of the pulmonary artery, arising from the right ventricle instead of the left ventricle.
• Tricuspid Atresia: This defect consists of the absence or malformation of the tricuspid valve through which blood flows from the right atrium to the right ventricle. 
• Ebstein’s Anomaly: Malformation of the tricuspid valve, which leads to the valve being displaced downwards into the right ventricle. 
• Hypoplastic Left Heart Syndrome (HLHS): A severe condition in which the left side of the heart is undeveloped.

Acyanotic Congenital Heart Disease

In these defects, oxygen levels in the blood remain normal (or near-normal), but blood circulation could be impaired. For instance: 

• Ventricular Septal Defect (VSD): A hole in the interventricular septum (the wall between the left and right ventricles). 
• Atrial Septal Defect (ASD): A hole in the interatrial septum (the wall between the left and right atria). 
• Patent Ductus Arteriosus (PDA): The ductus arteriosus, a blood vessel that connects the aorta and the pulmonary artery in the fetus, does not close after birth. 
• Coarctation of the Aorta: A narrowing or constriction of the aorta, often in the area where the aortic arch meets the descending aorta. 
• Pulmonary Stenosis: Narrowing of the pulmonary valve (the valve between the right ventricle and the pulmonary artery), hindering blood flow from the right ventricle to the lungs.
• Aortic Stenosis: Narrowing of the aortic valve (the valve between the left ventricle and the aorta), obstructing blood flow from the left ventricle to the aorta and, consequently, the body.

How is Congenital Heart Disease Diagnosed?

Early diagnosis of CHD is primarily important because it allows for immediate management. Various diagnostic methods are used to assess both the structure and function of the heart. 

• Echocardiogram: This is at the top of the CHD diagnosis. It is among the most widely used non-invasive test types, and it provides real-time images of the heart using ultrasound technology. 
• Electrocardiogram (ECG or EKG): An electrocardiogram records the electrical activity of the heart. 
• MRI and CT: MRI (Magnetic Resonance Imaging) and CT (Computed Tomography) Scans: These imaging techniques provide detailed, cross-sectional views of the heart and its surrounding structures, including the blood vessels. 
• Cardiac Catheterization: A more invasive procedure involves inserting a thin, flexible tube (catheter) into a blood vessel (often in the leg or arm) and guiding it to the heart. 
• Pulse Oximetry: This simple, non-invasive test measures the oxygen saturation in the blood, helping to detect low oxygen levels (hypoxemia) associated with cyanotic heart defects.
• Genetic Testing: Genetic testing can be done to identify specific genetic mutations or chromosomal abnormalities linked to CHD. 
• Fetal Echocardiogram: This specialised ultrasound is performed during pregnancy to assess the fetal heart. 
• Chest X-ray: A chest X-ray can provide information about the size and shape of the heart and lungs and can also reveal the presence of fluid in the lungs.

Treatment Options for Congenital Heart Disease

Treatment modalities range from conservative medical management to complex surgical interventions.

Medications

Medications include:

• Diuretics: Reduce fluid retention (edema and decrease the workload on the heart by increasing urine production.
• ACE Inhibitors and ARBs: These medications help lower blood pressure, improve heart function, and reduce the risk of heart failure.
• Beta-blockers Slow the heart rate and reduce blood pressure, improving heart function and controlling arrhythmias.
• Anticoagulants (blood thinners): Prevent blood clots in individuals at risk, such as those with certain valve abnormalities or arrhythmias.
• Antiarrhythmics: Regulate irregular heart rhythms (arrhythmias).
• Prostaglandin E1: A medication used in newborns with certain heart defects to keep the ductus arteriosus open, allowing blood to flow to the lungs or the body.
• Inotropes: Medications that increase the strength of the heart’s contractions.

Catheter-Based Procedures

Procedures include:

• Balloon Angioplasty: Used to widen narrowed blood vessels or heart valves (e.g., pulmonary stenosis or aortic stenosis). 
• Stent Placement: Used to keep arteries or vessels open, ensuring adequate blood flow. 
• Device Closure: Used to close holes in the heart, such as ASDs, VSDs, or PDAs. 
• Valve procedures: Balloons may be used to stretch narrowed valves (valvuloplasty), and stents may be placed to keep the valve open.

Surgery

Types of surgery include:

• Open-Heart Surgery: Major surgical procedures performed through an incision in the chest, often requiring the use of a heart-lung machine to temporarily take over the heart’s function. 
• Heart Valve Repair or Replacement: When heart valves are severely damaged or malformed, they may be repaired or replaced with artificial valves or valves from other sources.
• Fontan Procedure: This surgery is performed for patients with single-ventricle heart defects, where one of the ventricles does not function correctly.
• Heart Transplant: In the most severe cases of CHD, where other treatment options are exhausted or are not feasible, a heart transplant may be necessary. 
• Pacemakers and Implantable Cardioverter-Defibrillators (ICDs): These devices are used to manage arrhythmias and prevent sudden cardiac arrest.

Congenital Heart Disease Life Expectancy

Factors influencing life expectancy and long-term outlook:

• Type and Severity of the Defect: The complexity and severity of the CHD are the main determinants.
• Early Diagnosis and treatment would avert complications and optimise outcomes.
• Quality of Health Care: The availability of specialised cardiologists (for paediatrics and adults) along with competent and experienced surgical teams is essential.
• Adherence to a Healthy Lifestyle: The advantages of following a heart-healthy lifestyle include using a balanced diet, exercising most days a week, refraining from smoking, and restricting alcohol.
• Medical Recommendations: These include taking medication as prescribed, when indicated, going for regular checkups, and receiving follow-up care.
• Presence of Complications: The presence of complications in the form of heart failure, arrhythmias, pulmonary hypertension, or endocarditis may alter the long-term outlook.
• General Health and Presence of Other Illnesses: The presence of other concomitant illnesses can also alter the prognosis. 

With effective medical care, individuals with CHD can minimise complications, control their condition, and improve their quality of life.

Atrius Cardiac Care for a Healthy Heart

If you are looking for guidance on congenital heart disease, the professional team at Atrius Cardiac Care is here to help. With extensive experience in cardiology, the skilled team of doctors provide compassionate, expert care tailored to your needs.