Atrial fibrillation (AF) is the most common sustained heart rhythm abnormality. Its incidence is increasing partly due to the ageing population and it has been referred to as a growing epidemic. AF results in irregular contractions of the heart causing unpleasant symptoms of palpitations and increasing the risk of stroke, heart failure and death. Percutaneous catheter ablation is a safe treatment option in symptomatic patients with AF. The success rate of these procedures have improved with time due to our better understanding of AF, development of new techniques and technology, and greater physician experience. However, the success rate of these procedures still only remains around 70%. This is contributed to our limited ability to find the areas that drive the AF.