In the first of a series of blogs, I will look at abnormal heart rhythms, (known as arrhythmias,) the associated symptoms and how diagnosis is made, and the common issues for medical negligence claims.
What is arrhythmia?
Cardiac arrhythmia is an irregular rhythm of the heart: There are many different types of cardiac arrhythmia, which may increase (tachycardia) or slow (bradycardia) the heart rate. Some abnormal heart rhythms start in the atria, which are the upper chambers of the heart (supraventricular arrhythmias), and some start in the ventricles which are the lower chambers (ventricular arrhythmias).
The heart beat normally starts with an electrical impulse in the right atrium (at the sinoatrial node), which travels across the top chambers of the heart, and then through to the bottom chambers. This helps to push blood from the top to the bottom of the heart, and then out to the rest of the body. Irregular heartbeats are caused by interruptions to the heart’s electronic impulses. It may be due to a problem conducting the electrical impulses, or because there is a problem with the heart’s natural pacemaker.
People of any age can suffer from abnormal heart rhythms, and there are a large number of causes: For example if the heart tissue has been damaged, then it may not conduct electrical impulses properly, in some conditions there is a structural abnormality such as additional electrical pathways, and in other conditions chemical changes in the cardiac cells affect heart rhythm.
Many people are affected by cardiac arrhythmias, and although most will not suffer any major complications, it can affect quality of life, and some people will be at risk of dangerous arrhythmias, which can cause cardiac arrest. This is linked to Sudden Arrhythmic Death Syndrome (SADS). Therefore it is very important that irregular heartbeats are appropriately investigated, diagnosed, and treated.
What are the symptoms?
Some of the common symptoms of irregular heartbeats are:-
- Palpitations – Heart palpitations are a sudden awareness of your heart beating. This may feel like the heart is pounding, fluttering, or beating irregularly. This can last for anything from a few seconds to a few minutes.
- Dizziness / fainting
- No symptoms. Some people with cardiac arrhythmias may not experience any symptoms
How is arrhythmia diagnosed?
The NHS recommends that anyone who is worried about symptoms, particularly heart palpitations that have increased in frequency, or which are accompanied by dizziness or tightness in the chest, should go to their GP .
The following tests may be used to diagnose arrhythmia:-
ECGs (Electrocardiogram) – This is a simple test, in which electrodes are stuck to the chest, arms, and legs. These record the electrical activity of the heart.
Holter monitor – This is a portable version of the ECG, which can be worn for a longer period of time, such as 24 / 72 hours. This is used because arrhythmias may not be constant, and so the heart is monitored for a longer period of time to record the arrhythmia.
Exercise ECG – Some arrhythmias may only occur during exercise, and so an ECG test can be carried out whilst the patient is exercising in a controlled environment, normally on a treadmill.
Loop recorder – Where the arrhythmias are less regular an indwelling recording device called a ’loop recorder’ may be implanted to monitor the heart.
Heart screening programmes
As I have mentioned above, some people with abnormal heart rhythms do not present with symptoms. Because of the small risk of serious complications, there are campaigns and heart screening programmes run by charities such as Cardiac Risk in the Young  and the Arrhythmia Alliance , for simple tests and heart screening to detect undiagnosed heart conditions.
Potential legal issues regarding diagnosis of arrhythmias
From my experience of dealing with negligence cases, key issues to consider in the diagnosis of arrhythmia are:-
- Appropriate referrals by GPs: When a patient presents to their GP with symptoms that could indicate a heart condition, it is important that the GP recognises this, that they arrange appropriate tests and make appropriate referrals to a cardiologist.
- Taking a full history: It is important to find out whether there is a family history of heart problems and whether symptoms such as breathlessness, dizziness, and fainting are present.
- Mistakes in diagnosis: Sometimes symptoms caused by arrhythmias can be wrongly attributed to other causes. For example, patients who suffer fainting caused by arrhythmia. This is why it is important to take a full history, and to carry out appropriate tests.
- Appropriate referrals to arrhythmia specialists: There are specialist cardiologists who have been trained in the treatment of arrhythmias, known as electrophysiologists. It is important that general cardiologists recognise when it is appropriate to refer patients to see an electrophysiologist, who are often based at ‘tertiary’ (specialist) centres.
- Although a lot of arrhythmias may not present a serious health risk, because of the potentially serious and life threatening risks of some conditions, it is important that appropriate tests are carried out before dismissing a condition as ‘benign’.