Ablação por cateter do flutter atrial. Caracterização eletrofisiológica da interrupção da condução pelos istmos posterior e septal

• Autor(a) principal: Moreira, José Marcos [UNIFESP]
• Data de Publicação: 1998
• Outros Autores: Alessi, Sílvio Roberto Borges [UNIFESP], Rezende, André Gustavo Da Silva [UNIFESP], Prudêncio, Luis Alberto Renjel [UNIFESP], De Paola, Angelo Amato Vincenzo [UNIFESP]
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300000f75t
• DOI: 10.1590/S0066-782X1998000700008
• Texto Completo: http://dx.doi.org/10.1590/S0066-782X1998000700008; http://repositorio.unifesp.br/handle/11600/649
• topic: atrial flutter; catheter ablation; radiofrequency; flutter atrial; ablação por cateter; radiofreqüência

PURPOSE: Evaluate the different types of conduction blocks obtained between inferior vena cava-tricuspid annulus (posterior isthmus) and between tricuspid annulus-coronary sinus ostium (septal isthmus) after radiofrequency (RF) catheter ablation of atrial flutter (AFL) METHODS: In 16 procedures, 14 patients (pts), 9 male, with type I AFL underwent RF ablation. Atrial activation around tricuspid annulus was performed with a 10-bipole Halo catheter (H1-2; H19-20). In sinus rhythm, isthmus conduction was evaluated during proximal coronary sinus (PCS) and low lateral right atrium (H1-2) pacing, before and after linear ablation. According to the wave front of impulse propagation we assessed absence of block (bidirectional conduction); incomplete block (bidirectional conduction with delay in one front of impulse propagation) and complete block (absence of conduction). The PCS/H1-2 interval was measured before and after ablation. RESULTS: Complete isthmus block was achieved in 7 (44%) and incomplete block in 4 (25%) procedures. Conduction block was not achieved in 5 procedures. At a mean follow-up of 12 months, there were no recurrences in the pts with complete block, whereas AFL recurred in the 6 pts with incomplete or no conduction block (p<0.001). Pts with complete block had deltaPCS/H1-2 interval (74.0 ± 26.0ms) greater than incomplete (30.5 ± 7.5ms) or absent block (p<0.05). CONCLUSION: The verification of complete isthmus conduction block with atrial multipolar mapping is an effective strategy to assess electrophysiological success and absence of late recurrence in common atrial flutter ablation.