BACKGROUND: Percutaneous epicardial mapping has been used for ablation of recurrent ventricular tachycardia (VT). OBJECTIVES: The purpose of this study was to use a combined epicardial and endocardial mapping strategy to delineate the myocardial substrate for recurrent VT in both ischemic (n = 12) and nonischemic cardiomyopathy (n = 8), and to define the role of epicardial ablation. METHODS: Electroanatomic mapping was performed in 20 patients. High-density voltage maps were obtained by acquiring both endocardial and epicardial electrograms. Electrograms derived from six patients with structurally normal hearts were used as controls. A total of 26 VTs were targeted in the 20 patients. RESULTS: Most VTs (23/26 [88.5%]) were hemodynamically unstable. In patients with ischemic cardiomyopathy, the extent of endocardial scar was greater than epicardial scar. A definable pattern of scar could not be demonstrated in nonischemic cardiomyopathy. Pathologic examination of explanted hearts in two patients with nonischemic cardiomyopathy demonstrated that low-voltage areas were not always predictive of scarred myocardium. A substrate-based approach was used for catheter ablation. Catheter ablation was performed on the endocardium in all patients; additional epicardial delivery of radiofrequency energy was required in 8 (40%) of 20 patients for successful ablation. During follow-up (12 +/- 4 months), 15 (75%) of 20 patients have been arrhythmia-free. CONCLUSION: Patients with ischemic cardiomyopathy tend to have a larger endocardial than epicardial scar. Use of epicardial and endocardial electroanatomic mapping to define the full extent of myocardial scars allows successful catheter ablation in patients with hemodynamically unstable VTs.
BACKGROUND: Percutaneous epicardial mapping has been used for ablation of recurrent ventricular tachycardia (VT). OBJECTIVES: The purpose of this study was to use a combined epicardial and endocardial mapping strategy to delineate the myocardial substrate for recurrent VT in both ischemic (n = 12) and nonischemic cardiomyopathy (n = 8), and to define the role of epicardial ablation. METHODS: Electroanatomic mapping was performed in 20 patients. High-density voltage maps were obtained by acquiring both endocardial and epicardial electrograms. Electrograms derived from six patients with structurally normal hearts were used as controls. A total of 26 VTs were targeted in the 20 patients. RESULTS: Most VTs (23/26 [88.5%]) were hemodynamically unstable. In patients with ischemic cardiomyopathy, the extent of endocardial scar was greater than epicardial scar. A definable pattern of scar could not be demonstrated in nonischemic cardiomyopathy. Pathologic examination of explanted hearts in two patients with nonischemic cardiomyopathy demonstrated that low-voltage areas were not always predictive of scarred myocardium. A substrate-based approach was used for catheter ablation. Catheter ablation was performed on the endocardium in all patients; additional epicardial delivery of radiofrequency energy was required in 8 (40%) of 20 patients for successful ablation. During follow-up (12 +/- 4 months), 15 (75%) of 20 patients have been arrhythmia-free. CONCLUSION:Patients with ischemic cardiomyopathy tend to have a larger endocardial than epicardial scar. Use of epicardial and endocardial electroanatomic mapping to define the full extent of myocardial scars allows successful catheter ablation in patients with hemodynamically unstable VTs.
Authors: Saman Nazarian; Sergey V Kantsevoy; Menekhem M Zviman; Fredrick A Matsen; Hugh Calkins; Ronald D Berger; Henry R Halperin Journal: Heart Rhythm Date: 2008-05-09 Impact factor: 6.343
Authors: Roderick Tung; Marmar Vaseghi; David S Frankel; Pasquale Vergara; Luigi Di Biase; Koichi Nagashima; Ricky Yu; Sitaram Vangala; Chi-Hong Tseng; Eue-Keun Choi; Shaan Khurshid; Mehul Patel; Nilesh Mathuria; Shiro Nakahara; Wendy S Tzou; William H Sauer; Kairav Vakil; Usha Tedrow; J David Burkhardt; Venkatakrishna N Tholakanahalli; Anastasios Saliaris; Timm Dickfeld; J Peter Weiss; T Jared Bunch; Madhu Reddy; Arun Kanmanthareddy; David J Callans; Dhanunjaya Lakkireddy; Andrea Natale; Francis Marchlinski; William G Stevenson; Paolo Della Bella; Kalyanam Shivkumar Journal: Heart Rhythm Date: 2015-05-30 Impact factor: 6.343
Authors: Shiro Nakahara; Roderick Tung; Rafael J Ramirez; Yoav Michowitz; Marmar Vaseghi; Eric Buch; Jean Gima; Isaac Wiener; Aman Mahajan; Noel G Boyle; Kalyanam Shivkumar Journal: J Am Coll Cardiol Date: 2010-05-25 Impact factor: 24.094