An Insight Into Sudden Death in Children
Sudden death in children may occur due to various causes, but it is mostly due to an underlying cardiovascular pathology.
Sudden cardiac death is seen more often in males than females. The risk of sudden cardiac death increases as does the age. The main cause of the sudden cardiac death in children is hypertrophic cardiomyopathy except in Italy where it is mostly due to arrhythmogenic right ventricular cardiomyopathy (ARVC). Eighty-two percent of sudden cardiac deaths are evidenced during physical exertion in competitions or while training.
What are the Risk Factors for Sudden Death in Children?In babies <1yr of age, sudden death is called sudden infant death syndrome (SIDS), which is a different entity.
In children >1yr of age, sudden death may occur due to either cardiac or non-cardiac causes.
- Non-Cardiac Causes
Road traffic accidents, fall, choking/aspiration, poisoning, epilepsy, stroke, drowning, etc.
- Cardiac Causes
- Hypertrophic Cardiomyopathy(HCM): It is the disease caused due to thickening of the muscular layer of the heart. It is a familial (hereditary) disorder and autosomal dominant in inheritance. The mechanism behind sudden cardiac arrest in this condition is due to the abnormal electrical activity of the lower heart chamber. An arrest can be the first manifestation in the patient. An implantable cardioverter defibrillator (ICD)which monitors the electrical rhythm of the heart as well as delivers a therapeutic shock when the heart escapes out of the rhythm is a treatment option.
- Dilated Cardiomyopathy (DCM): It is a heart muscle disease involving the dilatation of the left ventricle of the heart. Dilated cardiomyopathy is due to inflammation of heart muscle layer (myocarditis), ischemic (restriction of blood supply) injury, toxins or hereditary. Implantable cardioverter defibrillator and heart transplantation are the treatment options.
- Commotio Cordis: Sudden cardiac arrest due to blunt injury to the anterior chest wall in children, without any pre-existing cardiac illness is called commotio cordis. It usually happens in athletes. Administration of the cardiopulmonary resuscitation (CPR)and defibrillation on time helps in saving life.
- Coronary Anomalies: Anomalous (faulty) origin of the coronary arteries which supply the heart causes sudden arrest on exertion. It manifests if the anomaly results in the compression of the coronary artery. Surgical correction is the treatment.
- Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy (ARVC): It is a disease of the muscle layer of the right lower heart chamber. The disease progresses through 4 phases. Presentation of the disease could be arrhythmias (heart rhythm abnormality), heart failure or a sudden death. The treatment depends on the phase of the disease and the presentation.
- Marfan Syndrome: It is a disorder involving the connective tissue and follows an autosomal dominant pattern of inheritance. Dilatation of the root of the aorta (the blood vessel which carries away the pure oxygenated blood from the heart to the body organs) is seen in Marfan syndrome, which can result in a sudden death. Screening the patients with Marfan syndrome with the help of transthoracic echocardiogram is essential to prevent sudden death. Beta blockers and surgical correction of the aorta are the treatment options depending upon the extent of aortic root dilatation.
- Kawasaki Disease: It is a disease in children involving the blood vessels due to an inflammatory process. It can cause coronary artery lesions and result in death. To prevent the lesions, patients with Kawasaki disease should be treated with IV gamma globulins and aspirin during the initial period of fever. Surgical correction of the coronary lesion is the treatment.
- Takayasu Arteritis: It is a disease which involves blood vessels through an inflammatory process. Coronary arterial involvement in these patients can result in sudden death.
- Ion Channelopathies: Ion channels are the pores present on the cell membrane which help in the transfer of ions (like sodium, calcium, potassium, etc.) between the cell interior and cell exterior. The conditions involving the ion channels are collectively called ion channelopathies.
Brugada syndrome (It is a heart ion channel disorder leading to heart rhythm disturbances), long QT syndrome (a familial disorder which causes heart rhythm disturbances due to cardiac ion channel mutation), short QT syndrome (a disorder due to heart ion channel mutation) and catecholaminergic polymorphic ventricular tachycardia (a disorder due to the mutation of calcium ion channel in the heart). All of these are the genetically inherited ion channelopathies which cause arrhythmias (heart rhythm disturbances) and may result in sudden death. Some patients present with cardiac arrest as the first symptom and some with recurrent syncope. Hence, in patients with recurrent syncope, screening for history and ECG are encouraged. Treatment with an ICD (Implantable Cardioverter Defibrillator) or antiarrhythmic as per the need can prevent the cardiac arrest.
- Congenital Heart Diseases: These can lead to sudden death due to arrhythmias, emboli (freely moving foreign material in the blood vessel like a blood clot), etc.
What are the Warning/Alarming Symptoms Before Sudden Death in Children?Most of the children have alarming symptoms like syncope (temporary loss of consciousness), near syncope, seizure/fit, lightheadedness, fatigue, chest pain, palpitations (feeling fast heartbeats)and shortness of breath.
How Do You Diagnose the Risk of Sudden Death in Children?
- History: If a child has warning symptoms or has a history of sudden death in the family, further clinical assessment and investigations are required. It is precautionary to undergo preparticipation evaluation among athletes.
- Electrocardiogram: Electrocardiogram (ECG)is an important investigation which can detect the rhythm disturbances associated with the underlying cardiac conditions.
- Echocardiogram: It useful in diagnosing and monitoring the heart function in patients with heart pathology like hypertrophic cardiomyopathy, dilated cardiomyopathy, aortic dilation in Marfan Syndrome and aneurysms of coronaries in Kawasaki Disease, ventricular dimensions in arrhythmogenic right ventricular cardiomyopathy (rare disease of the heart muscle).
- Genetic Testing: In the case of sudden death in a family, with an autopsy (post-mortem examination) showing no positive results, genetic analysis will play an important role to detect the cause and hence help to take precautions among family members.
- CT Scan /MRI: These radiological imaging techniques help to detect the coronary artery lesions in Kawasaki Disease, Takayasu arteritis.
How Do You Treat Sudden Death in Children?Considering the patient health condition and the disease presentation, the appropriate treatment should be administered.
- Antiarrhythmic Drugs: These are the drugs which help to treat the heart rhythm disturbances. Beta blockers are the drugs of choice in Long QT Syndrome but if symptoms recur on beta blocker treatment, an ICD is indicated. Beta blockers are used in patients with catecholaminergic polymorphic ventricular tachycardia (heart rhythm problems). Amiodarone, beta-blockers, sotalol, etc. are useful to treat non-life-threatening arrhythmias in patients with arrhythmogenic right ventricular cardiomyopathy.
- Implantable Cardioverter Defibrillator (ICD): It helps to prevent fatal arrhythmia-related sudden death. In patients with ion channelopathies, hypertrophic cardiomyopathy ICD is essential.
- Angioplasty: It is indicated in the case of stenotic (narrowed) or aneurysmal (dilatational) coronary artery lesions.
- Cardiac Ablation: Ablation is required in the case of life-threatening arrhythmias in arrhythmogenic right ventricular cardiomyopathy.
Cardiopulmonary Resuscitation, public availability of Automatic External Defibrillator (AED) help in immediate defibrillation and increase the chance of survival.
Preparticipation Evaluation Among Athletes
Sudden death in children is precipitated by physical exertion, so preparticipation evaluation of participants in competitions is necessary. It involves taking history regarding the warning symptoms and family history of sudden deaths. Physical examination involves blood pressure (BP) measurement, checking the pulses, heart auscultation and assessment of Marfan syndrome. Electrocardiogram and echocardiogram are not included in routine.. In patients suspicious to have the heart problem, further testing and avoiding strenuous activity are essential.
Screening Children with a Family History of Sudden Cardiac Death
Screening children with a family history of sudden cardiac death offers an opportunity to diagnose the pre-symptomatic disease, and helps in the prevention of sudden death by treating appropriately.
Automatic External Defibrillator (AED) Availability: Automatic external defibrillatoris a devicewhich is used to shock the heart in case of sudden cardiac arrest. The availability of automatic external defibrillator (AED) in public places and high school, aids in early defibrillation of the heart and hence saves many lives. Defibrillation is a common treatment in which an electronic device gives an electric shock to the heart.