Dr V Thomas
Dr Vinod Thomas is a cardiologist based in Cape Town. After completing his BSc (anatomy) in Archaeology under the tutelage of the late Professor Philip Tobias at the University of Witwatersrand, he went on to obtain his Medical Degree (MBCHB, WITS) at the same institute.
Dr Thomas completed his internship at the Pietersburg Tertiary Hospital and community service at Elim District Hospital. During that time, he trained in multiple disciplines, including internal medicine, surgery, emergency medicine, anaesthesia, obstetrics and gynaecology, paediatric medicine and psychiatry. He then worked as a medical officer in the UK (Portsmouth, Exeter and Brighton NHS Hospitals), covering specialities including emergency medicine, acute medicine, internal medicine and geriatric medicine.
Cardiac Devices
Arrhythmia
An abnormal or irregular heartbeat is known as arrhythmia. Often arrhythmias occur in normal functioning hearts and are benign. Still, they can cause some uncomfortable symptoms, which affect the quality of life, and can cause serious conditions in some cases.
Cardiac electrophysiologists assess arrhythmias. Factors such as the patient’s symptoms and clinical situation are considered to find the most suitable treatment option.
Types of arrhythmia
There are a number of types of arrhythmia. These include:
- Arrhythmia
When the heartbeat is irregular or originates in an area of the heart other than the sino-atrial node, it is called arrhythmia. There are different types of arrhythmia, such as bradyarrhythmia, a slow heartbeat and tachyarrhythmia, an unusually fast heartbeat. - Bradyarrhythmia
Bradyarrhythmia is a heart rhythm that is too slow, slower than 60 beats per minute. When the heart's rhythm is too slow to meet the body's metabolic demands, you may experience symptoms like shortness of breath, dizziness, and fainting. This is typically a sign of an underlying issue with the heart. Your cardiologist may recommend a pacemaker for bradyarrhythmia. - Tachyarrhythmias
Tachyarrhythmias occur when electrical impulses are generated in an area of the heart other than the sino-atrial node, and the heart beats too fast, over 100 beats a minute. These arrhythmias sometimes occur in normal functioning as well as abnormal hearts. Symptoms of a tachyarrhythmia include heart palpitations, chest pains, shortness of breath, dizziness and fainting.
Atrial Fibrillation
Atrial fibrillation is a condition that occurs when the heart beats irregularly, at a quick pace, over 100 beats every minute. As a result, symptoms of dizziness, feeling faint and losing oxygen start to occur.
How does the heart work?
The heart is made up of four chambers – the right and left atria and the larger right and left ventricles. The atria pump blood into the ventricles, while the ventricles pump blood throughout the body. The right side of the heart pumps blood to the lungs so that they have access to oxygen, and the left side pumps blood to the body and brain.
When the heart is functioning normally, the atria pump blood to the ventricles before the ventricles pump blood to the body, so the atria and ventricles work in sequence. To make sure that the chambers are all in sequence and to control the speed at which the heart beats, it has an electrical timing system.
Small cells in the sinus node at the top of the heart send an electrical impulse out 60 to 80 times per minute, which means that the normal rate at which the heart beats is between 60 to 80 times a minute, with an increase during exercise. The impulse moves across the atria from right to left, causing the cells of the atria to contract. An insulated line separates the atria and ventricles from each other. When the electrical wave reaches the line, it ends, and the cells wait for the next electrical impulse from the sinus node.
The atria are connected to the ventricles by the atrioventricular node and bundle branches, which act as electrical paths through which the electrical waves can spread, causing the ventricles to contract. Thus, when an electrical wave is sent, it moves from the top to the bottom of the heart before it dies out until the next impulse is sent.
