Search

Background: Electrical storm due to recurrent ventricular tachycardia (VT) in patients with implantable cardioverter defibrillator (ICD) can adversely affect their long-term survival. This study evaluates the efficiency of the radiofrequency catheter ablation of electrical storm due to monomorphic VT in patients with idiopathic dilated cardiomyopathy (DCM) and assesses its long-term effects on survival., Methods and Results: Between April 2004 and October 2008, 13 consecutive patients (nine men, mean age 56.8 ± 17.8 years) with DCM and electrical storm due to monomorphic VT who had ICD underwent 17 catheter ablation procedures, including four epicardial, at our center. Acute complete success was defined as the lack of inducibility of any VT at the end of procedure during programmed right ventricular stimulation and was achieved in eight patients (61.5%). During a median follow-up of 23 months (range 3-63 months) nine patients (69%) were alive and eight patients (61.5%) were free from VT recurrence. Among those with acute complete (n = 8) and partial (n = 5) success, seven patients (87.5%) and one patient (20%) were free from any VT recurrence and ICD therapy, respectively (P = 0.025). Among those with acute complete and partial success, seven patients (87.5%) and two patients (40%) were alive, respectively (Mantel-Cox test P = 0.082). Among those who had an initially failed endocardial ablation (n = 8), four underwent further epicardial ablation that was completely successful in three patients (75%)., Conclusion: Catheter ablation in patients with DCM and electrical storm due to monomorphic VT who had an ICD prevents further VT recurrence in 61.5% of the patients. Complete successful catheter ablation may play a protective role and was associated with reduced mortality during the follow-up period. More aggressive ablation strategies in patients with initially failed endocardial ablation might improve the long-term survival of these patients; however, further studies are needed to clarify this issue., (©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.)

Background: A remote magnetic navigation system (MNS) has been used for ablation of ventricular arrhythmias. However, irrigated tip catheter has not been evaluated in large series of patients., Objective: To evaluate acute and long-term efficiency of the newly available irrigated tip magnetic catheter for radiofrequency (RF) ablation of scar-related ventricular tachycardia (VT) in patients with ischemic heart disease., Methods: Between January 2008 and October 2009, a total of 30 consecutive patients with ischemic heart disease (26 men, age 70.1 ± 8.7 years, left ventricular ejection fraction: 30 ± 9%) and electrical storm due to monomorphic VT underwent RF ablation using a remote MNS and a magnetic irrigated tip catheter., Results: Acute success was defined as noninducibility of any monomorphic VT during programmed right and left ventricular stimulation, and obtained in 24 (80%) patients. A total of 1-6 VTs (mean 2.3 ± 1.2, 394 ± 108 ms, 210-660 ms) were inducible during each procedure. The duration of RF energy application was 41.2 ± 23.3 minutes, with total procedure and fluoroscopy times of 158 ± 47 minutes and 9.8 ± 5.3 minutes, respectively. No acute complications were observed during the procedures. During mean follow-up of 7.8 months, 21 patients (70%) had no recurrence of VT and received no implantable cardioverter defibrillator therapy. Among patients who were noninducible during programmed right ventricular stimulation (n = 25), ≥1 monomorphic VT was inducible during programmed left ventricular stimulation in four (16%) that was ablated successfully in three of them., Conclusions: Irrigated ablation of scar-related VT using remote MNS is an effective modality for management of the monomorphic VT in patients with ischemic cardiomyopathy with minimal radiation exposure. Programmed left (in addition to right) ventricular stimulation might be necessary to assess acute outcome of the ablation procedure., (©2010, The Authors. Journal compilation ©2010 Wiley Periodicals, Inc.)

A 41-year-old woman with recurrent wide-QRS tachycardia is reported. Electrophysiologic findings were consistent with the diagnosis of a preexcited atrioventricular nodal reentrant tachycardia due to a bystander nodo-ventricular fiber. However, slow pathway ablation did not preclude tachycardia recurrence. A second electrophysiology study shed light on the correct mechanism and eventually a successful ablation was achieved.