PO-04-110 MAPPING TRENDS IN AVNRT ABLATION: AN INTERNATIONAL ANALYSIS

Abstract

Electroanatomic mapping (EAM) in AVNRT procedures is an ongoing area of interest due to AVNRT prevalence and safety considerations, particularly in pediatric populations. The utility of voltage mapping to identify the slow pathway has been documented. However, use of mapping techniques differs widely across geographies, and trends in clinical practice of these techniques and the acute outcomes have not been quantified. To assess mapping patterns in AVNRT procedures by geography. Acute observational data from 484 AVNRT procedures were prospectively collected from 125 centers in 12 countries in North and South America, Europe, and Australia. Choice of mapping and ablation strategy was left to physician discretion. Procedure data (mapping approach, catheter choice, and number of Ablation lesions required Before Consolidation (ALBC)) were compared to analyze acute outcomes and regional use trends. There was a significant difference in EAM use in AVNRT cases in the US vs. OUS (89.5% vs. 64.5%, respectively, p<.05). Low voltage bridge (LVB) mapping was the most frequently used technique globally; 37.7% of US and 52.7% of OUS cases (p<.05). Wavefront collision mapping (WFC) and Local Activation Time (LAT) mapping applying isochronal late activation mapping concepts saw high use in the US (WFC: 28.2%, LAT: 22.3%) but infrequently OUS (7.5%, p<.05; 4.3%, p<.05). Fractionation mapping was uncommon in all regions (US 1.4%, OUS 0%; p>.05) (Figure 1). There was a significant decrease in ALBC between procedures that used EAM and those that did not (4.39±5.5 and 6.6±9.0 ablation lesions, respectively, p=.01). ALBC was also significantly different by mapping catheter choice, with cases that used HD Grid requiring fewer ablation lesions than cases that mapped with ablation or linear catheters (3.7±3.9, 5.4±7.1, and 6.0±6.8, respectively, p=.02). There was a significant difference in mapping catheter choice in the US vs. OUS (Table 1). In all regions analyzed, LVB mapping was the most common EAM technique and ablation catheters were the most commonly used mapping catheter. There were significant regional differences in the rate of EAM use and technique. Procedures that used EAM required fewer ALBC, an effect further amplified in the cases using HD Grid. Therefore, use of both EAM and HD Grid may help to minimize ALBC in AVNRT, an important safety and efficiency consideration. Further analysis exploring long-term efficacy by approach in a protocol-driven cohort may be warranted.Tabled 1Table 1.USOUSAblation Catheter54.0% (n=122)58.1% (n=111)HD Grid30.1% (n=68)34.6% (n=66)Linear Mapping Catheter16.0% (n=36)7.3% (n=14)Prevalence of mapping catheter choices compared between cases in the US and OUS. All differences were significant (p<.05) Open table in a new tab