News That Made The Headlines: Heart Block Disorder And Pacemaker
By Dr Hasri Samion, Senior Consultant Paediatric Cardiologist, Institut Jantung Negara
The heart is one of the most vital organs, as it delivers blood, oxygen and other nutrients to every part of the body.
Therefore, any minor disruption to its functions can be detrimental. One such interference is heart block – a condition that affects the heart’s electrical system and causes it to beat too slowly.
According to IJN Senior Consultant Paediatric Cardiologist Dr Hasri Samion, the condition has various degrees depending on the extent of electrical signal impairment.
He said heart block, or slow heart rate condition can be either congenital (present at birth) or due to heart diseases and heart surgery.
Dr Hasri cautioned that a congenital heart block does not heal over time with the child’s growth and requires immediate medical attention to avoid any risks.
He said the condition is more common among newborns whose mothers had an immunological illness called Systemic Lupus Erythematosus during pregnancy. “If the mother exhibits any symptom of the condition during pregnancy, it’s best to treat the mother to reduce the risk on the
child.”
The common symptoms of heart block include shortness of breath, fatigue or feeling weak, confusion, fainting spells, change in skin colour (turning blue) and difficulty when exercising.
To diagnose the condition, Dr Hasri said the patient should undergo an electrocardiogram (ECG) test for 24 hours to record the heart’s electrical activity.
“If there are abnormal rhythms and the heart pauses for more than three to four seconds, it means the patient has heart block and needs urgent treatment to avoid life- threatening consequences such as hypoxia (lack of oxygen supply at the tissue level),” said Dr Hasri who is also IJN’s chief clinical officer.
Pacemaker
According to Dr Hasri, the most common treatment for patients with heart block is to implant a pacemaker in their chest or abdomen.
He explained that a pacemaker is a small battery-operated microprocessor to regulate the heart’s electrical system and eventually control the heart rhythm.
For the uninitiated, with each heartbeat, an electrical impulse is sent from the top to the bottom of the heart, signalling the heart’s muscles to contract.
The process helps with blood circulation.
“Modern pacemakers come in two parts. One is called the generator which contains the battery to power the device, while the other part consists of two small wires called leads.”
He said the heart normally contracts on a sequential basis to optimise its functions.
Therefore, Dr Hari added that whenever there’s a problem preventing the electrical impulse from reaching the pumping chambers, it causes abnormality.
“When that happens, the pacemaker delivers energy to trigger the pumping chamber back to normality.”
Dr Hasri also noted that the pacemakers are programmable whereby the specialist doctor can adjust the modes based on the patient’s condition.
“Every patient living with a pacemaker must often go for their regular check-up to ensure that the pacemaker’s functions are in order.
“We can also adjust the functions based on the patient’s daily activities to meet their needs.” A pacemaker can also track and record the user’s heartbeat to better facilitate the doctor with information about the patient’s arrhythmia.
Pacemaker implantation
Although most pacemakers come in one standard size, Dr Hasri said they have to take into account certain clinical considerations when it comes to implanting the device in younger patients.
According to him, growth rate and different daily activities are two main factors to consider in children who require a pacemaker. “These two factors will determine the mode selection and implantation placement in children.
“For young children, we may consider implanting the pacemaker in the abdomen instead of the heart to avoid any technical issues when they grow.”
Dr Hasri explained that the wires of a pacemaker come in a fixed length and may stretch out in small children when they grow up if it’s installed in the chest.
Hence, he said it’s easier to implant the device in the abdomen as the stretch risks are very minimal.
Dr Hasri said the generator can generally last up to 10 years but its longevity depends on the disease of the heart.
“The generator and the lead’s longevity depends on the severity of the heart condition. “If the disease is severe, it may overwork the generator and affect its longevity.”
Lifestyle changes
Although the pacemaker helps people living with heart block conditions to have a normal life, Dr Hasri said certain lifestyle changes are still required to minimise the risks associated with the disease.
“Active children should avoid aggressive physical activities such as martial arts as it may damage the generator or the wiring.”
Additionally, he said they should always keep a healthy lifestyle to avoid any infections or diseases that affect the heart.
“We always recommend that the patients do follow-up screening every six months to check the generator, its battery life and the overall heart health.”
For those who require a follow-up operation to replace the generator, Dr Hasri said they can undergo a minimally-invasive key-hole surgery.