Dear Editor,
1.
We read the recent article by Tsunomori et al. entitled “Device‐Specific Responses to Pacemaker‐Mediated Arrhythmia in Patients With Prolonged Ventriculoatrial Conduction: A Comparative Simulation Study” with great interest [1]. The authors are to be commended for addressing an important and clinically relevant topic, particularly the variability in anti‐pacemaker‐mediated tachycardia (PMT) algorithms among different pacemaker manufacturers.
We would like to highlight several considerations that may further clarify the clinical applicability of these findings.
First and foremost, the study utilizes an electrophysiological simulation model to evaluate device behavior. While this approach allows standardized comparison under controlled conditions, as also acknowledged by the authors, it may not fully capture the complexity of in vivo physiology. In clinical practice, PMT is influenced by multiple dynamic factors, including autonomic tone, variability in ventriculoatrial conduction (VAC), and patient‐specific substrate [2, 3]. These factors may significantly affect both the initiation and maintenance of PMT, potentially leading to differences in device performance compared with simulation‐based observations. Therefore, caution is warranted when extrapolating these findings directly to clinical settings.
Second, the observed differences in device‐specific performance, particularly regarding post ventricular atrial refractory period (PVARP) behavior and atrial pacing adjustments, are noteworthy. However, device response in real‐world practice is highly dependent on individualized programming and patient‐specific conduction characteristics [2, 4]. As such, the apparent superiority of certain algorithmic features in a simulated environment may not consistently translate into improved clinical outcomes.
Third, the potential utility of DDI mode as an alternative strategy for managing PMT in the setting of prolonged VAC warrants careful consideration. Although the simulation findings suggest possible advantages, DDI mode may compromise atrioventricular (AV) synchrony, which is essential for optimal cardiac hemodynamics in many patients [5]. The clinical trade‐offs associated with this approach, particularly in patients with impaired ventricular function or reliance on AV synchrony, merit further discussion.
Finally, the analysis is limited to fixed VAC intervals (450 and 550 ms). In clinical settings, these intervals are often variable and influenced by physiological and pathological conditions. Evaluation across a broader and more dynamic range of conduction intervals may provide additional insight into device performance under real‐world conditions.
In conclusion, this study provides valuable insights into device‐specific PMT responses and highlights important differences among pacemaker algorithms. Further validation in clinical settings is necessary to determine how these findings can be translated into optimized device programming strategies and improved patient outcomes.
Conflicts of Interest
The author declares no conflicts of interest.
Data Availability Statement
Data sharing not applicable to this article as no datasets were generated or analysed during the current study.
References
- 1. Tsunomori M., Imamura T., Nagamine D., et al., “Device‐Specific Responses to Pacemaker‐Mediated Arrhythmia in Patients With Prolonged Ventriculoatrial Conduction: A Comparative Simulation Study,” Journal of Arrhythmia 23, no. 42 (2026): e70344, 10.1002/joa3.70344. [DOI] [PMC free article] [PubMed] [Google Scholar]
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- 5. Kristensson B. E., Arnman K., and Rydén L., “The Haemodynamic Importance of Atrioventricular Synchrony and Rate Increase at Rest and During Exercise,” European Heart Journal 6, no. 9 (1985): 773–778, 10.1093/oxfordjournals.eurheartj.a061940. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
Data sharing not applicable to this article as no datasets were generated or analysed during the current study.