Leadless pacemaker having wireless communication with subcutaneous ICD

Subcutaneous implantable cardioverter defibrillator was an innovation meant to reduce the lead related problems of conventional transvenous ICDs. But subcutaneous ICD cannot provide bradycardia and antitachycardia pacing as a transvenous ICD. To circumvent this problem, a modular communicative leadless pacing–defibrillator system has been devised and a study published in the New England Journal of Medicine [1]. It was a multinational study which enrolled patients at risk for sudden death from ventricular arrhythmias and the follow up period was 6 months.

151 patients completed the 6 month follow up period. Mean age was 60 years and mean left ventricular ejection fraction Was about 33%. 97.5% of patients were free from leadless pacemaker related major complications. Wireless communication between the devices was successful in 98.8% of communication tests. 97% had pacing thresholds of 2 Volts or less. 61.3% of arrhythmic episodes were successfully terminated with antitachycardia pacing. There were no episodes for which antitachycardia pacing was not delivered due to failure of communication. None of the deaths in the study were deemed to be arrhythmia related or procedure related.

This novel concept of combining a leadless pacemaker and a subcutaneous ICD was discussed ever since the two were developed separately for avoiding the Achilles Heel of pacemakers and ICDs, the intracardiac leads. Now we have a proof concept study report as well, in a reasonable number of patients. May be future studies with larger number of patients will follow and establish this as a novel mode of treatment in the needy persons.

Reference

1. Knops RE, Lloyd MS, Roberts PR, Wright DJ, Boersma LVA, Doshi R, Friedman PA, Neuzil P, Blomström-Lundqvist C, Bongiorni MG, Burke MC, Gras D, Kutalek SP, Amin AK, Fu EY, Epstein LM, Tolosana JM, Callahan TD, Aasbo JD, Augostini R, Manyam H, Nair DG, Mondésert B, Su WW, Pepper C, Miller MA, Grammes J, Saleh K, Marquie C, Merchant FM, Cha YM, Cunnington C, Frankel DS, West J, Matznick E, Swackhamer B, Brisben AJ, Weinstock J, Stein KM, Reddy VY, Mont L; MODULAR ATP Investigators. A Modular Communicative Leadless Pacing-Defibrillator System. N Engl J Med. 2024 May 18. doi: 10.1056/NEJMoa2401807. Epub ahead of print. PMID: 38767244.