Mohammad Hossein Nikoo1,2,3, Meghdad Khorshidifar4, Elham Nasrollahi5, Yaser Bahramvand5, Fatemeh Nouri4, Armin Attar6. 1. Department of Cardiovascular Medicine, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. 2. Cardiovascular Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. 3. Non-Communicable Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. 4. Students' Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran. 5. School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran. 6. Department of Cardiovascular Medicine, TAHA Clinical Trial Group, School of Medicine, Shiraz University of Medical Sciences, 71344-1864, Shiraz, Iran. attarar@sums.ac.ir.
Abstract
BACKGROUND: The earliest atrial (A)/ventricular (V) activation potentials, or fused A/V potentials, are commonly used as ablation targets for atrioventricular (AV) accessory pathways (APs). However, these targets can be achieved in a relatively wide area of the heart around AV rings at both atrial and ventricular sides. The aim of this study is to analyze the height of intracardiac A and V waves and their correlation to find the most appropriate side for successful delivery of radiofrequency energy, atrial or ventricular edge. METHODS: Ninety patients diagnosed with orthodromic AV re-entrant tachycardia (AVRT) or Wolff-Parkinson-White syndrome were enrolled. Local atrial/ventricular (A/V) amplitude potentials with the earliest activation or fused AV potentials were measured. Patients were randomly assigned into two groups with a 2:1 ratio. In group 1, ablation was done at the site where A was greater than V. In group 2, V was greater than A. Primary endpoint was success at first attempt, achieving antegrade AP conduction block, AV block during right ventricle pacing, or AVRT termination with no AP conduction. RESULTS: Fifty-one patients (56.7%) were male. Thirty patients had an ablation at an atrial site (A > V) and 60 at a ventricular site (V > A). Ablation was more successful at the ventricular site (87% vs 100%, P = 0.011). All 30 patients in the atrial arm and 71% of the ventricular group underwent ablation via the antegrade method. CONCLUSIONS: Success of catheter ablation of APs is higher where V > A (ventricular site of AP), indicating the priority of the ventricular edge of the mitral ring for a better outcome.
BACKGROUND: The earliest atrial (A)/ventricular (V) activation potentials, or fused A/V potentials, are commonly used as ablation targets for atrioventricular (AV) accessory pathways (APs). However, these targets can be achieved in a relatively wide area of the heart around AV rings at both atrial and ventricular sides. The aim of this study is to analyze the height of intracardiac A and V waves and their correlation to find the most appropriate side for successful delivery of radiofrequency energy, atrial or ventricular edge. METHODS: Ninety patients diagnosed with orthodromic AV re-entrant tachycardia (AVRT) or Wolff-Parkinson-White syndrome were enrolled. Local atrial/ventricular (A/V) amplitude potentials with the earliest activation or fused AV potentials were measured. Patients were randomly assigned into two groups with a 2:1 ratio. In group 1, ablation was done at the site where A was greater than V. In group 2, V was greater than A. Primary endpoint was success at first attempt, achieving antegrade AP conduction block, AV block during right ventricle pacing, or AVRT termination with no AP conduction. RESULTS: Fifty-one patients (56.7%) were male. Thirty patients had an ablation at an atrial site (A > V) and 60 at a ventricular site (V > A). Ablation was more successful at the ventricular site (87% vs 100%, P = 0.011). All 30 patients in the atrial arm and 71% of the ventricular group underwent ablation via the antegrade method. CONCLUSIONS: Success of catheter ablation of APs is higher where V > A (ventricular site of AP), indicating the priority of the ventricular edge of the mitral ring for a better outcome.