This Article Abstract Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Takahashi, A. Articles by Haïssaguerre, M. Search for Related Content PubMed PubMed Citation Articles by Takahashi, A. Articles by Haïssaguerre, M.

Partial cavotricuspid isthmus block before ablation in patients with typical atrial flutter

^a Electrophysiologie Cardiaque, Hôpital Cardiologique du Haut-Lévêque, Bordeaux-Pessac, France

View larger version (10K): [in a new window]   Figure 1 The technique of sequential withdrawal mapping. Sequential withdrawal mapping in the cavotricuspid isthmus was performed at high gain (0.1 mV/cm) from the margin of the tricuspid valve to the inferior vena cava in the line of electrograms coinciding with the center of the surface electrocardiographic plateau in inferior leads during counterclockwise (CCW) atrial flutter (AF) (left panel) and coinciding with the initial downslope of the positive flutter wave during clockwise (CW) AF (right panel). ABL = bipolar electrogram from ablation catheter.

View larger version (26K): [in a new window]   Figure 2 An example of withdrawal mapping in the cavotricuspid isthmus and ablation in a patient with preexisting partial cavotricuspid isthmus block. Left panel: A sequentially reconstituted withdrawal map in a patient before ablation during counterclockwise atrial flutter from the tricuspid valve (TV) edge to the inferior vena cava (IVC) edge. The atrial electrograms have been synchronized to the same timing with reference to the central dotted line bisecting the plateau in inferior leads on the surface electrocardiogram. Narrowly separated small double potentials (DPs) (arrows) are noted at the TV edge (top), followed by a fractionated potential centered on the reference line (star). During continued withdrawal, separated DPs are again noted. This interval widens progressively with further withdrawal as a result of an increasing delay of the second potential, as shown in the bottom three electrograms. Right panel: A single radiofrequency application at the fractionated electrogram site (star) terminated flutter 3.5 s later and produced bidirectional isthmus block. Note that termination occurs exactly in the center of the surface electrocardiographic plateau. Scale bars indicate 0.1 mV and 100 ms. V = ventricular electrogram. I, II, III, avR, avL, avF, V1–V6 = surface ECG leads.

View larger version (27K): [in a new window]   Figure 3 Another example of preexisting partial cavotricuspid isthmus block. Left panel: A sequentially reconstituted withdrawal map in a patient before ablation during counterclockwise atrial flutter (AF) from the tricuspid valve (TV) edge to the inferior vena cava (IVC) edge. Double potentials (DPs) are noted from midisthmus to the IVC edge (bottom three panels). Middle panel: The first radiofrequency (RF) application at a single potential with a far-field second potential near the TV (star) terminated AF without isthmus block. Right panel: Further withdrawal mapping during low lateral atrial pacing revealed a fractionated electrogram near the previous ablation site (right upper panel). A second RF application at this gap site resulted in widely separated DPs (right bottom panel) and eliminated isthmus conduction. Scale bars indicate 0.1 mV and 100 ms. ABL = bipolar electrogram from ablation catheter; V = ventricular electrogram.