Catheter ablation and antiarrhythmic drugs for haemodynamically tolerated post-infarction ventricular tachycardia; long-term outcome in relation to acute electrophysiological findings.
OBJECTIVE
Radiofrequency catheter ablation is effective at terminating ventricular tachycardia, but the overall clinical role of the technique in patients with a prior myocardial infarction is still debated, due to the uncertainties of the long-term reliability of the procedure. The purpose of this study was to prospectively investigate the relationship between acute results obtained by catheter ablation and long-term outcome in a homogeneous population of patients with post-myocardial infarction ventricular tachycardia.


RESULTS
One hundred and twenty-four consecutive patients with recurrent, drug-refractory, haemodynamically tolerated ventricular tachycardia were included in the study. This population accounted for 30% of the patients with post-myocardial infarction ventricular tachycardia admitted between April 1992 and September 1997 to the investigating centres. The ablation was successful in eliminating sustained ventricular tachycardia in 91 of them (73%); a partial result was obtained in 21 (17%) and failure in 12 (10%). Low dose amiodarone and/or beta-blockers were maintained in 86% of the patients. Over a median follow-up of 41.5 months (interquartile range 30.5-59.5 months), there were 15 deaths (12%), three of which were sudden (2.4%); the 12 remaining patients died of heart failure. Event-free survival analysis showed a significantly lower ventricular tachycardia recurrence rate in patients with a successful procedure as compared to those with failure or a partial result (19% vs 53% at one year and 27% vs 60% at 3 years, P=0.003). A repeat procedure was performed in 15 patients with early recurrences and was followed in all by long-term success. Of those who submitted to a second procedure, 93/124 patients (75%) are free of ventricular tachycardia recurrences. An implantable cardioverter-defibrillator (ICD), following procedure failure, was implanted in 13 patients (11%) of the study population.


CONCLUSIONS
Radiofrequency catheter ablation is effective in a wide population of patients with recurrent tolerated ventricular tachycardia, with very low sudden death and cardiac mortality rates over the long-term. Persistent ventricular tachycardia inducibility after catheter ablation requires an ICD implant and/or repeat ablation.
Della Bella
P
P
Centro Cardiologico Monzino, Institute of Cardiology, University of Milan, Milan, Italy.
De Ponti
R
R
Uriarte
J A S
JA
Tondo
C
C
Klersy
C
C
Carbucicchio
C
C
Storti
C
C
Riva
S
S
Longobardi
M
M
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D017115:Catheter Ablation; D017147:Defibrillators, Implantable; D018572:Disease-Free Survival; D004562:Electrocardiography; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications*; D017180:Tachycardia, Ventricular / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D000638:Amiodarone