Long-term results after ablation of infarct-related ventricular tachycardia.
OBJECTIVE
The purpose of this study was to assess the long-term effects of ablation of infarct-related ventricular tachycardia (VT) and the subsequent requirement for implantable cardioverter-defibrillator (ICD) therapy.


BACKGROUND
The long-term consequences after initially successful catheter ablation of infarct-related VT remain unclear.


METHODS
Forty patients who presented with infarct-related VT were studied using noncontact mapping to guide ablation.


RESULTS
One hundred forty VTs were mapped using the noncontact mapping system, including 36 (25.7%) clinical VTs. An endocardial exit site was determined in 100% of VT circuits, diastolic endocardial activity in 77 VTs (55%), and complete circuits in 24 VTs (17.1%). Eighty-one VTs (57.9%) were targeted for ablation, of which 67 (82.7% of targeted) were successfully ablated, including 27 clinical VTs (75% of clinical). Documented recurrence of an ablated VT occurred in 7.5% of patients over 36.3 +/- 21.0 months of follow-up. Episodes of new or recurrent, nontargeted VT or ventricular fibrillation (VF) occurred in 37.5% and VT recurrence without documentation of cycle length in 5%. In patients with ICDs, mean shock frequency was reduced from 6.8 +/- 7.3 per month in the year prior to ablation to 0.05 +/- 0.12 per month after ablation, over 24.7 +/- 18.9 months of follow-up (P < .0001).


CONCLUSIONS
In patients with infarct-related VT, noncontact mapping-guided VT ablation is associated with a high procedural success rate, and VT recurrence necessitating ICD therapy delivery is significantly reduced. However, only 42.5% of patients remain free from VT/VF 3 years after ablation. Catheter ablation for infarct-related VT is indicated as an adjunctive therapy in patients with symptomatic VT but cannot substitute for ICDs and antiarrhythmic drugs.
Segal
Oliver R
OR
St. Mary's Hospital and Imperial College of Medicine, London, United Kingdom.
Chow
Anthony W C
AW
Markides
Vias
V
Schilling
Richard J
RJ
Peters
Nicholas S
NS
Davies
D Wyn
DW
D000368:Aged; D017115:Catheter Ablation; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications; D012008:Recurrence; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000401:mortality / Q000601:surgery*; D016896:Treatment Outcome