Author + information
- Received March 7, 2012
- Revision received May 7, 2012
- Accepted May 17, 2012
- Published online January 1, 2013.
- Carine F. van Huls van Taxis, MD⁎,
- Adrianus P. Wijnmaalen, MD, PhD⁎,
- Sebastiaan R. Piers, MD⁎,
- Rob J. van der Geest, PhD†,
- Martin J. Schalij, MD, PhD⁎ and
- Katja Zeppenfeld, MD, PhD⁎,⁎ ()
- ↵⁎Reprint requests and correspondence:
Dr. Katja Zeppenfeld, Department of Cardiology, Leiden University Medical Center, Postal Zone C-05-P, PO Box 9600, 2300 RC Leiden, the Netherlands
Objectives This study aimed to evaluate the feasibility and accuracy of real-time integration of multidetector computed tomography (MDCT) derived coronary anatomy and epicardial fat distribution and its impact on electroanatomical mapping and ablation.
Background Epicardial catheter ablation for ventricular arrhythmias (VA) is an important therapeutic option in patients after endocardial ablation failure. However, epicardial mapping and ablation are limited by the presence of coronary arteries and epicardial fat.
Methods Twenty-eight patients (21 male, age 59 ± 16 years) underwent combined endo-epicardial electroanatomical mapping. Prior to the procedure, MDCT derived coronary anatomy and epicardial fat meshes were loaded into the mapping system (CARTO XP, Biosense Webster Inc, Diamond Bar, California). Real-time registration of MDCT data was performed after endocardial mapping. The distance between epicardial ablation sites and coronary arteries was assessed by registered MDCT and angiography. After the procedure, mapping and ablation points were superimposed on the MDCT using a reversed registration matrix for head-to-head comparison of mapping data and corresponding fat thickness.
Results Image registration was successful and accurate in all patients (position error 2.8 ± 1.3 mm). At sites without evidence for scar, epicardial bipolar voltage decreased significantly (p < 0.001) with increasing fat thickness. Forty-six VA were targeted; 25 (54%) were abolished by catheter ablation, in 21 (46%) ablation failed. In 5 VA no target site was identified and in 3 VA adhesions prevented mapping. In 2 VA ablation was withheld due to His-bundle vicinity and in 7 VA due to proximity of coronary arteries. In 4 VA catheter ablation was ineffective. At ineffective ablation sites epicardial fat was significantly thicker compared to successful sites (16.9 ± 6.8 mm [range 7.3 to 22.2 mm] and 1.5 ± 2.1 mm [range 0.0 to 6.1 mm], p = 0.002).
Conclusions Real-time image integration of pre-acquired MDCT information is feasible and accurate. Epicardial fat >7 mm and the presence of coronary arteries are important reasons for epicardial ablation failure. Visualization of fat thickness during the procedure may facilitate interpretation of bipolar electrograms and identification of ineffective ablation sites.
Dr. van Huls van Taxis is supported by the Netherlands Heart Society (grant 2008B074). Dr. van der Geest is a consultant for Medis Medical Imaging Systems. Dr. Schalij received unrestricted departmental grants from Medtronic, Boston Scientific, and Biotronik. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received March 7, 2012.
- Revision received May 7, 2012.
- Accepted May 17, 2012.
- American College of Cardiology Foundation