Role of catheter-induced mechanical trauma in localization of target sites of radiofrequency ablation in automatic atrial tachycardia

Abstract

An AP interval > or = 30 ms and a pace-mapping concordant sequence were reliable mapping features for predicting the outcome of the ablation procedure. Mechanical interruption of atrial tachycardia improved the specificity and positive predictive value of these two mapping techniques.

Electrophysiologic Characteristics and Topographic Distribution of Focal Atrial Tachycardias in Dogs

“…The result was similar to the same measure in people (À21 and À51 ms). 4,7,15,36,[38][39][40][41][42][43] The presence of negative unipolar recordings with QS configuration was associated with a correct identification of the target site of successful ablation, with a reported acute success rate of 86%. 33,40 In our study, all target areas for ablation presented this unipolar deflection morphology.…”

“…In our opinion the difference in the occurrence of TICM found in our population of dogs, when compared with human beings, can be because of the small number of dogs studied, because ventricular rate of FATs observed in this study ranged between 164 and 270 bpm and was higher than the one reported in people (130-240 bpm). 4,8,36,[38][39][40][41] The mechanism of FAT can be determined by the induction mode. [4][5][6] Reported incidence of FATs caused by abnormal automaticity in people ranges between 7 and 16%, while nonautomatic FATs ranged between 4 and 20%.…”

“…Fractioned potential consisted of 3 or more consecutive negative deflections with low peakto-peak amplitude (Fig 2A-D). 35,36 The presence of disorganized atrial activity, characterized by irregular f waves with variable voltage, was considered diagnostic for AF. 34 When AF was already present or induced during the study, transthoracic electrical cardioversion with bipolar shock was used to restore sinus rhythm.…”

Focal Atrial Tachycardia

“…3) Focal AT can be diagnosed in children or adults without any structural heart disease, but in the elderly it is often associated with cardiovascular disease. [4][5][6][7][8][9][10][11][12][13][14][15][16][17] The persistent or incessant form of focal AT can cause congestive heart failure due to tachycardia-induced cardiomyopathy, which is more frequent in pediatric patients than in adults. 18,19) …”

“…The earliest activation timing at the successful ablation site is usually at least 30 ms before the P-wave onset, but may vary greatly among the patients. [4][5][6][7][8][9][10][11][12][13][14][15][16][17] Due to the conventional endocardial mapping technique has limited resolution, several specialized mapping catheters has been developed. A self-expandable multielectrode basket catheter (Constellation, Boston Scientific) can also facilitate for simultaneous global atrial endocardial mapping to rapidly identify the AT origin and to navigate the ablation catheter inside the basket catheter (Astronomer System, Boston Scientific).…”