Anatomical characteristics of the cavotricuspid isthmus in patients with and without typical atrial flutter: Analysis with two- and three-dimensional intracardiac echocardiography
- 79 Downloads
The cavotricuspid isthmus (CTI) is crucial in the ablation of typical atrial flutter (AFL), and consequently the CTI anatomy and/or its relation to resistant ablation cases have been widely described in human angiographic studies. Intracardiac echocardiography (ICE) has been shown to be a useful tool for determining detailed anatomical information. Thus, this technology may also allow the visualization of the anatomical characteristics of the CTI, providing an opportunity to further understand the anatomy.
We conducted a study to compare the anatomy of the CTI between the patients with and without AFL and to characterize the anatomy of the CTI in the patients with AFL resistant to ablation.
Materials and methods
Twelve patients with typical AFL and 20 without AFL were enrolled in the study. Two-dimensional (2D) intracardiac echocardiography (ICE) was performed. The recordings were obtained with a 9F, 9-MHz ICE catheter from the right ventricular outflow tract to the inferior vena cava by pulling the catheter back 0.3 mm at a time under guidance with echocardiographic imaging in a respiration-gated manner. Three-dimensional (3D) reconstruction of the images of the CTI were made with a 3D reconstruction system. After the acquisition of the ICE, the CTI ablation was performed in the patients with AFL.
The 2D and 3D images provided clear visualization of the tricuspid valve, coronary sinus ostium, fossa ovalis and Eustachian valve/ridge (EVR). The CTI was significantly longer in the patients with AFL than in those without AFL (median length 24.6 mm (range 17.0–39.1 mm) versus median length 20.6 mm (range 12.5–28.0 mm), respectively, P < 0.05). However, a deep recess due to a prominent EVR was observed in 9 of 12 (75%) patients with AFL and in 12 of 20 (60%) patients without AFL (N.S.). A deep recess and the relatively long CTI were related to aging in all the study patients, and that relationship was similar in a limited number of patients without AFL. In five patients with AFL resistant to ablation, a deep recess and prominent EVR were observed.
The 2D and 3D ICE were useful for visualizing the complex anatomy of the CTI and identifying the anatomical characteristics of the CTIs refractory to ablation therapy. The anatomical changes observed in the CTI region may simply be the result of aging and may partially be involved in the development of AFL.
KeywordsCavotricuspid isthmus Atrial flutter Catheter ablation Intracardiac echocardiography
Unable to display preview. Download preview PDF.
- 2.Feld, G. K., Fleck, R. P., Chen, P. S., Boyce, K., Bahnson, T. D., Stein, J. B., et al. (1992). Radiofrequency catheter ablation for the treatment of atrial flutter. Identification of a critical zone in the reentrant circuit by endocardial mapping techniques. Circulation, 86, 1233–1240.PubMedGoogle Scholar
- 13.Natale, A., Newby, K. H., Pisano, E., Leonelli, F., Fanelli, R., Potenza, D., et al. (2000). Prospective randomized comparison of antiarrhythmic therapy versus first-line radiofrequency ablation in patients with atrial flutter. Journal of the American College of Cardiology, 35, 1898–1904.PubMedCrossRefGoogle Scholar
- 15.Schumacher, B., Pfeiffer, D., Tebbenjohanns, J., Lewalter, T., Jung, W., & Luderitz, B. (1998). Acute and long-term effects of consecutive radiofrequency applications on conduction properties of the subeustachian isthmus in a type I atrial flutter. Journal of Cardiovascular Electrophysiology, 9, 152–163.PubMedGoogle Scholar
- 17.Saoudi, N., Poty, H., Anselme, F., Nair, M., Abdel Azziz, A., & Letac, B. (1998). Evolution of concepts and techniques in radiofrequency catheter ablation for the common type of atrial flutter. In N. Saoudi, W. Schels, & N. El-Scherif (Eds.), Atrial flutter and fibrillation: From basic to clinical applications. Armonk, NY: Futura.Google Scholar
- 22.Da Costa, A., Romeyer-Bouchard, C., Dauphinot, V., Lipp, D., Abdellaoui, L., Messier, M., et al. (2006). Cavotricuspid isthmus angiography predicts atrial flutter ablation efficacy in 281 patients randomized between 8 mm- and externally irrigated-tip catheter. European Heart Journal, 27, 1833–1840.PubMedCrossRefGoogle Scholar
- 23.Okumura, Y., Watanabe, I., Yamada, T., Ohkubo, K., Masaki, R., Sugimura, H., et al. (2004). Comparison of coronary sinus morphology in patients with and without atrioventricular nodal reentrant tachycardia by intracardiac echocardiography. Journal of Cardiovascular Electrophysiology, 15, 269–273.PubMedCrossRefGoogle Scholar
- 24.Okumura, Y., Watanabe, I., Yamada, T., Ohkubo, K., Sugimura, H., Hashimoto, K., et al. (2004). Relationship between anatomic location of the crista terminalis and double potentials recorded during atrial flutter: Intracardiac echocardiographic analysis. Journal of Cardiovascular Electrophysiology, 15, 1426–1432.PubMedCrossRefGoogle Scholar
- 25.Cabrera, J. A., Sanchez-Quintana, D., Ho, S. Y., Medina, A., & Anderson, R. H. (1998). The architecture of the atrial musculature between the orifice of the inferior caval vein and the tricuspid valve: the anatomy of the isthmus. Journal of Cardiovascular Electrophysiology, 9, 1186–1195.PubMedGoogle Scholar
- 28.Okishige, K., Kawabata, M., Yamashiro, K., Ohshiro, C., Umayahara, S., Gotoh, M., et al. (2005). Clinical study regarding the anatomical structures of the right atrial isthmus using intra-cardiac echocardiography: Implication for catheter ablation of common atrial flutter. Journal of Interventional Cardiac Electrophysiology, 12, 9–12.PubMedCrossRefGoogle Scholar
- 29.Spach, M. S., & Dolber, P. C. (1986). Relating extracellular potentials and their derivatives to anisotropic propagation at a microscopical level in human cardiac muscle. Evidence for electrical uncoupling side-to-side fiber connections with increasing age. Circulation Research, 58, 356–371.PubMedGoogle Scholar