Real World Performance of an Individualized Antitachycardia Pacing Algorithm

Background A novel individualized antitachycardia pacing (IATP) algorithm using the post-pacing interval for real-time control has been introduced. Performance information is limited to a small safety and feasibility study with additional single-center and case studies. A larger-scale analysis is needed to better understand algorithm performance. Methods De-identified remote monitoring transmissions from devices with the IATP therapy applied were randomly selected. Rhythms were classified and effects of the novel algorithm were assessed. For monomorphic ventricular tachycardias (MVTs) proportions of successful therapy, shock-free episodes, and acceleration were calculated using Generalized Estimating Equations to correct for multiple episodes and compute statistics of the algorithm’s performance. Results There were 2259 MVT episodes in 336 patients. IATP succeeded in 87.1% of MVT episodes with 89.9% of MVT episodes ultimately free of shock therapy. Based on multivariate analysis, significant factors in therapy success were programming of at least the recommended number of sequences (90% at least recommended vs 73%, p=0.00088) and female sex (95% for female vs 86%, p=0.002). A trend to higher success was found for MVT with cycle length of 320ms or greater (90% vs. 83%, p=0.10). The IATP accelerated 3.6% of MVT episodes. None of the available factors was significantly associated with acceleration in the multivariate analysis. Conclusions The IATP algorithm succeeded in large proportion of MVT episodes and with low acceleration in patients randomly selected from remote monitoring transmissions. Using at least the recommended number of sequences had the strongest association with successful therapy. CLINICAL PERSPECTIVE What is known A novel method for delivering antitachycardia pacing therapy using real-time feedback has been shown safe and feasible. Comparisons in computational studies and smaller case series suggest the novel method’s performance is superior to other antitachycardia pacing methods. What the study adds Under real-world programming and use, as evaluated on a large de-identified set of remote monitoring transmissions, the novel antitachycardia pacing algorithm treated monomorphic ventricular tachycardia episodes with high efficacy and a low proportion of acceleration. The strongest factor associated with successful therapy was programming at least the recommended number of pacing attempts.