 Atrial fibrillation AF is the commonest condition affecting the rhythm of the heart and causes an irregular and often rapid heartbeat. Developing this condition may cause significant health problems and symptoms that affect normal day-to-day activities. Patients with AF also have a shorter life expectancy on average. Tablets used to try to normalise the heart rhythm rarely work well. As a result, doctors have devised a treatment to try to cure this condition. Special wires called catheters are used to deliver heat energy called ablation on the inside surface of the heart. This technique has been used more and more in recent years for patients with troublesome symptoms due to AF. 