Percutaneous Endocardial Ablation of Scar-Related Ventricular Tachycardia
Reporter: Aviva Lev-Ari, PhD, RN
UPDATED on 11/15/2013
Atrial Fibrillation Catheter Ablation Versus Surgical Ablation Treatment (FAST)
A 2-Center Randomized Clinical Trial
- Lucas V.A. Boersma, MD, PhD, FESC;
- Manuel Castella, MD, PhD;
- WimJan van Boven, MD;
- Antonio Berruezo, MD;
- Alaaddin Yilmaz, MD;
- Mercedes Nadal, MD;
- Elena Sandoval, MD;
- Naiara Calvo, MD;
- Josep Brugada, MD, PhD, FESC;
- Johannes Kelder, MD;
- Maurits Wijffels, MD, PhD;
- Lluís Mont, MD, PhD, FESC
+Author Affiliations
From the Departments of Cardiology (L.V.A.B., J.K., M.W.) and Cardiothoracic Surgery (W.J.v.B., A.Y.), St. Antonius Hospital, Nieuwegein, the Netherlands, and Thorax Institute, Hospital Clinic, University of Barcelona, Barcelona, Catalonia, Spain (M.C., A.B., M.N., E.S., N.C., J.B., L.M.).
- Correspondence to Lucas V.A. Boersma, MD, PhD, FESC, Cardiology Department, St. Antonius Hospital, PO 2500, Nieuwegein, Netherlands. E-maill.boersma@antoniusziekenhuis.nl
Abstract
Background—Catheter ablation (CA) and minimally invasive surgical ablation (SA) have become accepted therapy for antiarrhythmic drug–refractory atrial fibrillation. This study describes the first randomized clinical trial comparing their efficacy and safety during a 12-month follow-up.
Methods and Results—One hundred twenty-four patients with antiarrhythmic drug–refractory atrial fibrillation with left atrial dilatation and hypertension (42 patients, 33%) or failed prior CA (82 patients, 67%) were randomized to CA (63 patients) or SA (61 patients). CA consisted of linear antral pulmonary vein isolation and optional additional lines. SA consisted of bipolar radiofrequency isolation of the bilateral pulmonary vein, ganglionated plexi ablation, and left atrial appendage excision with optional additional lines. Follow-up at 6 and 12 months was performed by ECG and 7-day Holter recording. The primary end point, freedom from left atrial arrhythmia >30 seconds without antiarrhythmic drugs after 12 months, was 36.5% for CA and 65.6% for SA (P=0.0022). There was no difference in effect for subgroups, which was consistent at both sites. The primary safety end point of significant adverse events during the 12-month follow-up was significantly higher for SA than for CA (n=21 [34.4%] versus n=10 [15.9%]; P=0.027), driven mainly by procedural complications such as pneumothorax, major bleeding, and the need for pacemaker. In the CA group, 1 patient died at 1 month of subarachnoid hemorrhage.
Conclusion—In atrial fibrillation patients with dilated left atrium and hypertension or failed prior atrial fibrillation CA, SA is superior to CA in achieving freedom from left atrial arrhythmias after 12 months of follow-up, although the procedural adverse event rate is significantly higher for SA than for CA.
Clinical Trial Registration—URL: http://clinicaltrials.gov. Unique identifier:NCT00662701.
Key Words:
SOURCE
http://circ.ahajournals.org/content/125/1/23.short
A single-center experience of clinical and electrophysiologic outcomes of patients undergoing percutaneous endocardial ablation of scar-related Ventricular Tachycardia (VT) is reported in
IMAJ Isr Med Assoc J 2010; 12: 667-670.
http://www.ima.org.il/imaj/ar10nov-04.pdf
Catheter ablation can control or prevent recurrent ischemic VT and reduce incidence of implantable cardioverter defibrillator (ICD) therapy. The ablation can be done during VT in patients with stable VTs or during sinus rhythm in patients with unstable unmappable VTs by targeting the scar border using electroanatomic substrate mapping. VT ablation should be offered to ischemic patients with recurrent uncontrolled VT. Radiofrequency ablation of VT in patients with ischemic cardiomyopathy was proposed to treat and control recurrent VT
J Cardiovasc Electrophys 2005; 16(Suppl 1): S59-70.
Curr Opin Cardiol 2005; 20: 42-7.
An experience with VT ablation in patients with ischemic cardiomyopathy using the electroanatomic mapping system (CARTO) was presented in
There are several reasons for the limited success of ischemic VT ablation. Ventricular scars are not electrically homogenous. They are composed of variable regions of dense fibrosis that create conduction block and surviving myocyte bundles with interstitial fibrosis and diminished coupling, which produce circuitous slow conduction paths that promote reentry
Repeated programmed stimulation typically induces more than one monomorphic VT. Multiple VTs can be due to different circuits in widely disparate areas of scar, different axis from the same region of the scar, or changes in activation remote from the circuit due to functional regions of block
Circulation 2007; 115: 2750-60.
Catheter ablation using conventional techniques are suitable for stable VT. VT reentry circuit can be defined using electroanatomic mapping (CARTO) only during stable and tolerable tachycardia. However, many patients with reduced ejection fraction secondary to coronary heart disease have unstable VTs. These patients do not tolerate sustained VT or rapid pacing. Thus, electric or pace mapping is not available in most cases (unmappable VT with catheter technique). In these cases, scar mapping and ablation can be done only during sinus rhythm using the CARTO system
IMAJ Isr Med Assoc J 2007; 9: 260-4.
Radiofrequency catheter ablation of ventricular tachycardia in the setting of ischemic cardiomyopathy has emerged recently as a useful adjunctive therapy to ICD. Scar related reentrant ventricular tachycardia is the most common underlying mechanism of sustained monomorphic VT in patients with ischemic heart disease.
Limitations of Alternative Treatment Methods:
1. Recurrent ICD shocks have had physiological and psychological side effects.
2. Antiarrythmic drugs are used to reduce incidence of ICD therapy, but their role in reducing mortality is not proven. In addition, these drugs have important side effects including pro-arrythmic effect and worsening of heart failure status.
Conclusions: Ablation of ischemic VT using electroanatomic scar mapping is feasible, has an acceptable success rate and should be offered for ischemic patients with recurrent uncontrolled VT.
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