RT Journal Article
T1 Usefulness of unipolar electrograms to detect isthmus block after radiofrequency ablation of typical atrial flutter
A1 Pérez Villacastín Domínguez, Julián
A1 Almendral Garrote, Jesús
A1 Arenal, Ángel
A1 Pérez Castellano, Nicasio
A1 González, Sergio
A1 Ortiz, Mercedes
A1 García Serrano, Javier
A1 Vallbona, Bartolome
A1 Moreno, Javier
A1 Fernández Portales, Javier
A1 González Torrecilla, Esteban
AB Background: RS morphology of the unipolar electrogram is associated with propagation of the wave front through the exploring electrode, whereas positive uniphasic (R) unipolar electrograms are characteristic of the end of activation.Methods and results: Unipolar electrograms were recorded in 45 consecutive patients with atrial flutter who were undergoing radiofrequency ablation (RFA). Bidirectional cavotricuspid isthmus (CTI) block was achieved in 44 patients. The unipolar electrogram obtained before RFA at the low anterolateral right atrium during coronary sinus pacing changed from RS, rS, or QS to R or Rs in all patients after clockwise CTI block was obtained. The morphology of unipolar electrograms recorded close to the coronary sinus during pacing from the low anterolateral right atrium changed from RS or rS to R or Rs in all but 4 patients after counterclockwise CTI block. In the patient in whom CTI block was not achieved, the RS morphology of the unipolar electrogram remained unchanged. In 18 patients, the results of the RFA were assessed with only the unipolar electrogram. The unipolar electrogram correctly predicted 100% and 89% of the cases of clockwise and counterclockwise CTI block, respectively.Conclusions: The creation of CTI block is associated with an easily detectable loss of negative components and development of an R or Rs pattern of the unipolar electrogram recorded close to the ablation line while pacing at the opposite side of the CTI.
PB Lippincott, Williams & Wilkins
SN 0009-7322
YR 2000
FD 2000-12-01
LK https://hdl.handle.net/20.500.14352/100210
UL https://hdl.handle.net/20.500.14352/100210
LA eng
NO Villacastin J, Almendral J, Arenal A, Castellano NP, Gonzalez S, Ortiz M, García J, Vallbona B, Moreno J, Portales JF, Torrecilla EG. Usefulness of unipolar electrograms to detect isthmus block after radiofrequency ablation of typical atrial flutter. Circulation. 2000 Dec 19;102(25):3080-5. doi: 10.1161/01.cir.102.25.3080
DS Docta Complutense
RD 8 abr 2025