Contact versus noncontact mapping for ablation of ventricular tachycardia in patients with previous myocardial infarction.
BACKGROUND
The aim of this study was to compare contact versus noncontact mapping for radiofrequency (RF) ablation of any sustained post-myocardial infarction (MI) ventricular tachycardia (VT).


METHODS
Forty patients with tolerated VT post-MI were randomized to RF ablation with contact (group 1) or noncontact (group 2) mapping systems. In both groups ablation of tolerated VT was guided by VT activation map confirmed by concealed entrainment. When untolerated VTs were induced, ablation was performed in group 1 according to pace mapping starting from the scar border zone and in group 2 according to the VT activation map confirmed by pace mapping.


RESULTS
No differences were seen between the groups in terms of acute success rate of clinical VT ablation (95% vs 100%, respectively; P = ns) and in the noninducibility of any VT at the end of the procedure (55% vs 85%, respectively; P = 0.08). Moreover, untolerated VTs were eliminated in 30% of group 1 versus 83.3% of group 2 patients (P < 0.05). The mean total procedural and fluoroscopy times were 236.4 +/- 42.7 and 29.0 +/- 7.8 minutes in group 1 and 144.5 +/- 50.8 and 23.4 +/- 5.8 minutes in group 2 (P < 0.001 and < 0.05, respectively). At a mean follow-up of 15.2 +/- 6.7 months no differences were seen in VT recurrences between groups, but noninducibility at the end of the procedure was predictive of freedom from recurrences (P < 0.001).


CONCLUSIONS
Both systems are useful for ablation of tolerated VT. Noncontact mapping is more effective for ablation of untolerated VT and allows the reduction of procedural and fluoroscopy times. Noninducibility at the end of the procedure seems predictive of freedom from recurrences during follow-up.
Pratola
Claudio
C
Chair of Cardiology, S. Anna University Hospital, Ferrara, Italy. ltt@unife.it
Baldo
Elisa
E
Toselli
Tiziano
T
Notarstefano
Pasquale
P
Artale
Paolo
P
Paolo
Artale
A
Ferrari
Roberto
R
D000368:Aged; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis* / Q000601:surgery*; D025321:Surgery, Computer-Assisted / Q000379:methods; D017180:Tachycardia, Ventricular / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery*; D016896:Treatment Outcome