MAPPING AND ABLATION OF ATRIAL TACHYCARDIA AFTER CATHETER RADIOFREQUENCY ABLATION ATRIAL FIBRILLATION
For the last decades the number of catheter ablations of atrial fibrillation (AF) have been steadily increasing. There are several catheter ablation patterns depending on the type of AF. Multiple ablations in the left atrium lead to the formation of fibrous zones which are considered to be the substrate for the development of scar-related arrhythmias. Focal atrial tachycardia develop usually after segmental ostial pulmonary vein isolation due to vein reconnection. Linear ablation strategies lead to the macro-reentrant atrial tachycardia and local reentries. From a practical point of view following algorithm of atrial tachycardia identification may be presented: 1) look for the pulmonary veins associated tachycardia; 2) exclude macro-reentry tachycardia; 3) map focal or local reentry, if presented. After mapping of the breakthroughs in the ablation lines, entrainment pacing for the detection of arrhythmia mechanism is useful. Special cardiac navigation systems are often used for the verification of arrhythmia mechanism. Vast majority of postablational arrhythmia may be successfully mapped using navigation systems combined with electrograms analysis and entrainment pacing maneuvers. Nowadays navigation systems allow to create geometry of the heart chambers and study activation sequence during focal and macro-reentry arrhythmia. But modern navigation techniques are very helpful in combination with classic electrophysiology principles and maneuvers for the arrhythmia verification.