AbstractBackgroundThe multielectrode array (MEA) enables noncontact mapping of cardiac arrhythmias; our experience is reviewed and reported.HypothesisThe MEA has a role as first line therapy in multiple arrhythmias.MethodsRetrospective and prospective analysis of all consecutive cases performed using the MEA over a 6 year period.ResultsElectrophysiological study and catheter ablation, 46% under general anaesthesia, using radiofrequency (RF), cryothermal and low energy direct current (DC) was performed in 66 procedures on 31 females and 29 males, average age 50.2 yrs (19.3–81.6); 8 patients underwent multiple procedures. 24 patients (36%) had undergone past ablation for the same arrhythmia. A wide variety of arrhythmias from all chambers were treated, majority right atrial (56%) and right ventricular (29%). Procedural success was complete in 77.4% and partial/indeterminate in 11.3%, highest in right atrial tachycardia, right ventricular outflow tract ectopy and typical atrial flutter (79, 82 and 100%). RF energy was most commonly used (67%) and DC carried 100% success. Ablation was delivered at ‘early activation’ and ‘breakout’ in focal arrhythmias. In re‐entrant circuits linear ablation transecting path of activation extending to regions of functional/anatomic block was performed. Two of 7 complications were attributed to the MEA: groin haematomas. At mean 12.4 mo follow up 56% were arrhythmia free, 15% asymptomatic or minimally symptomatic and 12 patients had new arrhythmias.ConclusionsThe MEA is effective, safe and suitable for first line therapy in multiple cardiac arrhythmias particularly in the right heart. Further study is warranted comparing it to other mapping techniques. Copyright © 2010 Wiley Periodicals, Inc.