Patients' and procedural characteristics of AV-block during slow pathway modulation for AVNRT-single center 10year experience

Wasmer K, Dechering DG, Köbe J, Leitz P, Frommeyer G, Lange PS, Kochhäuser S, Reinke F, Pott C, Mönnig G, Breithardt G, Eckardt L

Abstract

BACKGROUND: Permanent AV-block is a recognized and feared complication of slow pathway modulation for AVNRT. We aimed to assess incidence of transient and permanent AV-block as well as consequences of transient AV-block in a large contemporary AVNRT ablation cohort. METHODS: We searched our single center prospective ablation database for occurrence of transient and permanent AV-block during slow pathway modulation between January 2004 and October 2015. We analyzed patients' and procedural characteristics as well as outcome of patients in whom transient or permanent AV-block occurred. RESULTS: Of 9170 patients who underwent a catheter ablation at our institution between January 2004 and October 2015, 2101 patients (64{\%} women, mean age 50+/-18years) underwent slow pathway modulation. In three patients, permanent AV-block occurred during RF application. Additional two patients had transient AV-block that recovered (after a few minutes and 25min), but recurred within two days of the procedure. All five patients underwent dual chamber pacemaker implantation (0.2{\%}). Transient AV-block related to RF delivery occurred in 44 patients (2{\%}). Transient mechanical AV-block occurred in additional 17 patients (0.8{\%}). In 12 patients, ablation was continued despite transient AV-block. One of these patients developed permanent AV-block. CONCLUSION: Permanent AV-block following slow pathway modulation is a rare event, occurring in 0.2{\%} of patients in a large contemporary single center cohort. Transient AV-block is more frequent (2{\%}).