Author + information
- Received August 16, 2011
- Revision received November 9, 2011
- Accepted November 17, 2011
- Published online February 28, 2012.
- Dirk Vollmann, MD⁎,†,⁎ (, )
- William G. Stevenson, MD†,
- Lars Lüthje, MD⁎,
- Christian Sohns, MD⁎,
- Roy M. John, MD, PhD†,
- Markus Zabel, MD⁎ and
- Gregory F. Michaud, MD†
- ↵⁎Reprint requests and correspondence:
Priv. Doz. Dr. med. Dirk Vollmann, University Medical Centre Göttingen, Georg-August-University, Department of Cardiology and Pneumology, Division of Clinical Electrophysiology, Robert-Koch-Str. 40, 37075 Göttingen, Germany
Objectives The purpose of this study was to evaluate the prevalence and mechanism of a misleading long post-pacing interval (PPI) upon entrainment of typical atrial flutter (AFL) from the cavotricuspid isthmus (CTI).
Background In typical AFL, the PPI from entrainment at the CTI is expected to closely match the tachycardia cycle-length (TCL).
Methods Sixty patients with confirmed CTI-dependent AFL were retrospectively analyzed and grouped into short (≤30 ms) or long (>30 ms) PPI-TCL. Thereafter, we prospectively studied 16 patients to acquire the PPI-TCL at 4 CTI sites with entrainment at pacing cycle-lengths (PCLs) 10 to 40 ms shorter than the TCL. Conduction times during AFL and entrainment were compared in 5 segments of the AFL circuit.
Results Eleven patients (18%) in the retrospective analysis had a long PPI-TCL after entrainment from the CTI. Subjects with long PPI-TCL had similar baseline characteristics but greater beat-to-beat TCL variability. In the prospective cohort, PPI-TCL was influenced by the difference between PCL and TCL and site of entrainment. Conduction delays associated with a long PPI-TCL were located predominantly in the segment activated first by the paced orthodromic wave front, and were mainly due to local pacing latency, as confirmed by the use of monophasic action potential catheters.
Conclusions A long PPI upon entrainment of typical AFL from the CTI is common and due to delayed conduction with entrainment. Whether these findings apply to other macro–re-entrant tachycardias warrants further investigation.
Dr. John has received modest speaker honoraria from St. Jude Medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received August 16, 2011.
- Revision received November 9, 2011.
- Accepted November 17, 2011.
- American College of Cardiology Foundation