The stepwise ablation approach for chronic atrial fibrillation—Evidence for a cumulative effect
- 431 Downloads
Treatment options for atrial fibrillation (AF) have evolved from simple, fluoroscopy-guided pulmonary vein isolation for those patients with paroxysmal AF to complex, multi-modality procedures targeting not only anatomic structures but also electrophysiologic phenomena including complex fractionated electrograms, sites of dominant frequency and local non-venous drivers in patients with persistent and permanent AF. The stepwise ablation approach is a novel technique whereby structures contributing to initiation and maintenance of AF are sequentially targeted by radiofrequency ablation. Broadly divided into pulmonary veins, left atrial (LA) roof, left atrium (incorporating all anatomic regions of the chamber), mitral isthmus and non-LA structures, each region is targeted in sequence and the impact of ablation upon the global fibrillatory process assessed by measurement of AF cycle length (AFCL) at a site remote from the ablation target. In addition to pulmonary vein electrical disconnection and demonstrable complete conduction block across the roof and mitral isthmus lines (when performed), ablation is performed at those sites displaying continuous electrical and complex fractionated activity, with the endpoint of local organization, as well as at sites displaying electrograms consistent with focal sources driving AF. Ablation is accompanied by a cumulative increase in the AFCL prior to termination of AF by conversion either directly to sinus rhythm or to an atrial tachycardia which is then mapped conventionally and ablated. There is a ceiling of ablation within the LA beyond which further ablation is unlikely to result in a clinical benefit and should prompt evaluation of the contribution of the right atrium to maintenance of AF. The stepwise approach benefits from the integration of anatomic and electrophysiologic information to achieve a high level of success in termination of chronic AF by catheter ablation.
KeywordsAtrial fibrillation Catheter ablation Mapping Arrhythmia
Unable to display preview. Download preview PDF.
- 6.Kanagaratnam, L., Tomassoni, G., Schweikert, R., Pavia, S., Bash, D., Beheiry, S., et al. (2001). Empirical pulmonary vein isolation in patients with chronic atrial fibrillation using a three-dimensional nonfluoroscopic mapping system: Long-term follow-up. Pacing and Clinical Electrophysiology, 24(12), 1774–1779.PubMedCrossRefGoogle Scholar
- 7.Willems, S., Klemm, H., Rostock, T., Brandstrup, B., Ventura, R., Steven, D., et al. (2006). Substrate modification combined with pulmonary vein isolation improves outcome of catheter ablation in patients with persistent atrial fibrillation: A prospective randomized comparison. European Heart Journal. Retrieved from http://dx.doi.org/10.1093/eurheartj/ehl093.
- 8.Nademanee, K., McKenzie, J., Kosar, E., Schwab, M., Sunsaneewitayakul, B., Vasavakul, T., et al. (2004). A new approach for catheter ablation of atrial fibrillation: Mapping of the electrophysiologic substrate. Journal of the American College of Cardiology, 43(11), 2044–2053.PubMedCrossRefGoogle Scholar
- 13.Kottkamp, H., Hindricks, G., Autschbach, Ru., Krauss, B., Strasser, B., Schirdewahn, P., et al. (2002). Specific linear left atrial lesions in atrial fibrillation: Intraoperative radiofrequency ablation using minimally invasive surgical techniques. Journal of the American College of Cardiology, 40(3), 475–480.PubMedCrossRefGoogle Scholar
- 20.Calo, L., Lamberti, F., Loricchio, M. L., De Ruvo, E., Colivicchi, F., Bianconi, L., et al. (2006). Left atrial ablation versus biatrial ablation for persistent and permanent atrial fibrillation: A prospective and randomized study. Journal of the American College of Cardiology, 47(12), 2504–2512.PubMedCrossRefGoogle Scholar
- 21.Haissaguerre, M., Hocini, M., Sanders, P., Sacher, F., Rotter, M., Takahashi, Y., et al. (2005). Catheter ablation of long-lasting persistent atrial fibrillation: Clinical outcome and mechanisms of subsequent arrhythmias. Journal of Cardiovascular Electrophysiology, 16(11), 1138–1147.PubMedCrossRefGoogle Scholar
- 22.Verma, A., Kilicaslan, F., Adams, J. R., Hao, S., Beheiry, S. Minor, S., et al. (2006). Extensive ablation during pulmonary vein antrum isolation has no adverse impact on left atrial function: An echocardiography and cine computed tomography analysis. Journal of Cardiovascular Electrophysiology, 17(7), 741–746.PubMedCrossRefGoogle Scholar
- 24.Sanders, P., Hocini, M., Jaïs, P., Nalliah, C. J., Takahashi, Y., Hsu, L.-F., et al. (2006). Pulmonary vein isolation for atrial fibrillation. In S. K. Stephen Huang & M. A. Wood (Eds.), Catheter ablation of cardiac arrhythmias (1st ed., pp. 269–287). Philadelphia: Saunders Elsevier.Google Scholar
- 33.Tsai, C. F., Tai, C. T., Hsieh, M. H., Lin, W. S., Yu, W. C., Ueng, K. C., et al. (2000). Initiation of atrial fibrillation by ectopic beats originating from the superior vena cava: Electrophysiological characteristics and results of radiofrequency ablation. Circulation, 102(1), 67–74.PubMedGoogle Scholar
- 37.Nitta, T., Ishii, Y., Miyagi, Y., Ohmori, H., Sakamoto, S., & Tanaka, S. (2004). Concurrent multiple left atrial focal activations with fibrillatory conduction and right atrial focal or reentrant activation as the mechanism in atrial fibrillation. Journal of Thoracic and Cardiovascular Surgery, 127(3), 770–778.PubMedCrossRefGoogle Scholar
- 39.Sacher, F., Monahan, K. H., Thomas, S. P., Davidson, N., Adragao, P., Sanders, M., et al. (2006). Phrenic nerve injury after atrial fibrillation catheter ablation: Characterization and outcome in a multicenter study. Journal of the American College of Cardiology, 47(12), 2498–2503.PubMedCrossRefGoogle Scholar
- 44.Ahmed, J., Sohal, S., Malchano, Z. J., Holmvang, G., Ruskin, J. N., & Reddy, V. Y. (2006). Three-dimensional analysis of pulmonary venous ostial and antral anatomy: Implications for balloon catheter-based pulmonary vein isolation. Journal of Cardiovascular Electrophysiology, 17(3), 251–255.PubMedCrossRefGoogle Scholar