Cardiac Arrhythmia

Cardiac Arrythmia is a condition in which the heart’s normal rhythm is disrupted. The heart may beat too slowly, too quickly or with an irregular rhythm.

Most arrhythmias are harmless, but some can be serious and potentially fatal. Disturbed heart rhythms can restrict blood being pumped around the body, which may cause damage to the brain, heart and other organs.

Over 1 million people in the UK experience heart arrhythmias and they account for one in ten visits to hospital.


Common causes of arrhythmia are stress, caffeine, tobacco, alcohol, diet pills and cough and cold medicines.

You may also be at risk of developing an arrhythmia if your heart tissue is damaged because of an illness, such as a heart attack, heart failure or inflammation of the heart.


Initial symptoms of arrhythmia include: heart palpitations, a skipped beat or a ‘fluttering’ sensation in the chest. The longer the arrhythmia lasts, the more likely that this condition can affect the way the heart works, causing a range of secondary symptoms.

These include:

  • Fatigue
  • Blackouts
  • Dizziness
  • Breathlessness
  • Rapid heartbeat or pounding
  • Chest pain

In extreme cases, certain types of arrhythmia can cause sudden cardiac death.


A range of tests can be used to diagnose arrhythmia. The main test used to detect abnormal heart rhythms is an electrocardiogram (ECG or EKG). Each beat of the heart is triggered by an electrical impulse generated by cells in the upper right heart chamber. An ECG translates this electrical activity into line tracings on a paper.

Other tests include:

  • Echocardiogram – this quick, simple, and painless test uses ultrasound waves to build a picture of the heart’s size, structure and function.
  • Exercise or stress test – this test is usually carried out on patients where the arrhythmia is thought to be linked to exercise. Patients are asked to walk or run on a treadmill or ride an exercise bike whilst their heart rate and rhythms are monitored.
  • Tilt test – For people who have experiences recurrent fainting spells, this test shows how standing up from a lying down position can affect heart rate and blood pressure


Most individuals who suffer from arrhythmias do not require treatment. However, if the arrhythmia is deemed clinically significant, in that it causes adverse symptoms or could cause complications in the future (e.g. heart failure or stroke), then a bespoke treatment plan is required. This may include medication, non-surgical or surgical procedures.

  • Medication – Medication such as beta blockers, calcium channel blockers and specific drugs which can be used to slow down a fast heart rate, whilst a range of medications can be used to restore a normal heart rate. Blood thinning medications may also be used.
  • Medical procedures – A range of medical procedures can be undertaken to help control arrhythmias. These include having a Pacemaker or Implantable Cardioverter Defibrillator (ICD) fitted. Both of these devices are inserted under the skin in the chest and use electrical impulses to shock the heart, which in turn helps to restore a normal heartbeat. In some cases, a procedure called Catheter Ablation may also be used which effectively destroys the part of the heart that is causing the arrhythmia.
  • Surgery – If heart disease is found to be the main cause of arrhythmia, then you may need to have a procedure called Coronary Artery Bypass Grafting (CABG). This will help to improve blood flow to the heart.

Case Studies

Patient Video: Pacemaker fitting for arrhythmia

John shares his story about having treatment at Harefield Hospital, under the care of Consultant, Dr David Jones.