Use of advanced mapping systems to guide ablation in complex cases: Experience with noncontact mapping and electroanatomic mapping systems

Objective: This report describes our experience with noncontact mapping and electroanatomic mapping in complex ablations, which are defined as ablations done after failure of conventional ablation. Material and Methods: Patients were included (N = 68; 49% with structural heart disease) in whom previous ablation failed and in whom a second procedure was done with advanced mapping. Non-contact mapping was used in 17 patients, electroanatomic mapping in 36, and both noncontact and electroanatomic mapping in 15. Arrhythmias included focal atrial tachycardia (n = 16), reentrant atrial tachycardia (n = 14), right ventricular outflow tachycardia (n = 10), post-myocardial infarction ventricular tachycardia (n = 9), and others (n = 19). Results: Acute success at the second ablation was achieved in 79% of patients. At 20 ± 9 months after the procedure, 69% of these patients reported having significantly fewer symptoms than before the second ablation, and 51% were free of symptoms. Only 16% were using antiarrhythmic medications. Complications included a small pericardial effusion in two patients, hypotension in one patient, and a femoral pseudoaneurysm in another. Conclusions: Advanced mapping is a useful and safe adjunct for catheter ablation after ablation has failed in patients with complex substrate.