Are you suffering from arrhythmia?
Posted on 1 July 2016
Everybody drums to their own beat – and there’s nothing wrong with that. But when your heartbeat starts hitting the wrong rhythm, you could be suffering from a heart rhythm disorder. We take a look at some of the most common types of arrhythmia.
What is arrhythmia?
The term arrhythmia refers to any change from the normal sequence of electrical impulses. The electrical impulses may happen too fast, too slowly or erratically, according to the American Heart Association. Arrhythmias are classified according to where they occur in your heart. Atrial arrhythmias occur in the area above the ventricles (supraventricular), in the upper chambers of the heart, or atria. Ventricular arrhythmias occur in the lower chambers of the heart, the ventricles, and if caused by heart disease these arrhythmias tend to be the most serious.
Common types of arrhythmia
1. Premature beats
These are the most common type of heart arrhythmia, and they can be atrial or ventricular. They’re mostly harmless and usually don’t have any symptoms – if anything, they might feel like a chest flutter or a skipped beat. Premature beats usually occur naturally, but some can be caused by heart disease, stress, excessive exercise, or stimulants like caffeine or nicotine.
Types of premature contractions
- Premature atrial contractions (PACs) start in the upper chambers of the heart (atria).
- Premature ventricular contractions (PVCs) start in the lower chambers of the heart (ventricles).
Occasionally premature beats may be caused by disease or injury to the heart. Your doctor may recommend more tests to make sure your heart is functioning normally otherwise.
2. Atrial fibrillation (AFib)
‘AFib is one of the most common arrhythmias in adulthood,’ says Dr Nico van der Merwe, a cardiologist at Mediclinic Bloemfontein. ‘Patients can be completely asymptomatic – especially the elderly – but most may experience a fast, irregular heartbeat or sudden shortness of breath.’
AFib has a very fast and irregular rhythm, and occurs when your heart’s electrical signal starts in the wrong part of the atrium, rather than in the sinoatrial (SA) node, which is your heart’s ‘pacemaker’. When this happens, the electrical signal can spread throughout the atria in a scattershot way, causing the walls of the atria to shake (fibrillate) instead of beating normally. Chronic AFib can cause stroke or heart failure, while sudden AFib is often the result of an underlying condition such as hypertension or rheumatic heart disease.
3. Ventricular fibrillation (VFib)
VFib is the meaner brother of Afib. ‘This is mostly a life-threatening condition associated with structural heart disease or certain hereditary arrhythmogenic cardiac conditions,’ Dr Van der Merwe explains.
VFib usually occurs during or after a heart attack, or if your heart is weak because of another condition. It happens when the electrical signal in your heart goes haywire, making your ventricles quiver instead of pumping normally. Without your ventricles pumping blood into the body, you could quickly suffer sudden cardiac arrest. Dr Van der Merwe adds: ‘Some patients may experience syncope, which is a temporary loss of consciousness, but most have a sudden cardiac death.’ However for those at risk, an implanted defib device may be the answer.
It sounds like the name of a dinosaur. But in fact, it is what happens when your heart rate is slower than normal – in adults, that would be slower than 60 beats per minute (bpm). If this happens, you won’t get enough blood reaching your brain and you could lose consciousness. Some super-fit people have slow heart rates, and for them it’s perfectly safe. But if your heart rate is slow for other reasons – ageing, an underactive thyroid or side-effects of beta-blockers – you could be in trouble. Take your pulse, monitor your heart rate, and speak to a cardiologist if it starts dropping near the 60bpm mark.