Remote Magnetic Versus Manual Catheter Navigation for Atrial Fibrillation Ablation: A Meta-Analysis.

October 2019 1 Catheter ablation of atrial fibrillation (AF) is a technically challenging procedure with suboptimal long-term success rates, non-negligible risk of major complications, and significant radiation exposure. In recent years, remote magnetic navigation (RMN) systems have emerged that offer increased precision and greater stability of catheter-tissue contact. Despite considerable enthusiasm surrounding the potential benefits of RMN systems, a rigorous analysis of their impact on the clinical outcomes and procedural efficiency of AF ablation is lacking. We thus conducted a meta-analysis to assess the relative safety and efficacy of RMN versus manual catheter navigation (MCN) for AF ablation. We searched Medline, EMBASE, and CENTRAL (Cochrane Central Register of Controlled Trials) databases for controlled studies comparing outcomes of AF ablation performed with RMN versus MCN. The primary efficacy end point was freedom from AF at ≥1-year follow-up. The primary safety end point was major periprocedural complications. Secondary end points included fluoroscopy and procedure durations. Meta-analyses were performed using random-effects models. Fifteen observational studies met criteria for inclusion, involving a total of 3246 patients (RMN=1475; MCN=1771; Table).1–15 Compared with MCN, RMN was associated with reduced major periprocedural complications (relative risk, 0.51; 95% CI, 0.29–0.91; I2=0%; P=0.02). In the 12 studies with ≥1-year median followup, late recurrence of AF was not significantly reduced (relative risk, 0.97; 95% CI, 0.89–1.05; I2=0%; P=0.43). Fluoroscopy times were significantly shorter with RMN (mean difference, 13.3 minutes; 95% CI, 6.9–19.7; I2=99%; P<0.001) but total procedure (mean difference, 51.3 minutes; 95% CI, 32.0–70.6; I2=94%; P<0.001) and radiofrequency ablation (mean difference, 15.7 minutes; 95% CI, 8.2–23.2; I2=94%; P<0.001) durations were significantly longer. In our meta-analysis, RMN was associated with almost 50% lower risk of major procedural complications compared with MCN. The enhanced safety of RMN may be because of lower contact force exerted by magnetic-tipped catheters and their increased flexibility. Although prior studies have largely failed to demonstrate a significant risk reduction, they were likely underpowered because of their small sample sizes and low event rates.1,3,5,9,12,13 Of note, the population in this metaanalysis represents a relatively low-risk AF cohort with preserved left ventricular function in the majority of patients and few comorbidities. Further studies are thus required to assess whether the safety benefits of RMN translate to higher-risk AF ablation cohorts. Long-term freedom from AF following catheter ablation is dependent on the formation of durable transmural lesions that maintain bidirectional conduction block between ablated sites and surrounding cardiac tissue. Stability of cathetertissue contact is a key determinant of lesion size and transmurality. It has thus been hypothesized that the greater catheter stability and precision offered by RMN SPECIAL REPORT