Response by van der Stuijt et al to Letter Regarding Article, "Efficacy and Safety of Appropriate Shocks and Antitachycardia Pacing in Transvenous and Subcutaneous Implantable Defibrillators: Analysis of All Appropriate Therapy in the PRAETORIAN Trial".

Abstract

HomeCirculationVol. 146, No. 4Response by van der Stuijt et al to Letter Regarding Article, “Efficacy and Safety of Appropriate Shocks and Antitachycardia Pacing in Transvenous and Subcutaneous Implantable Defibrillators: Analysis of All Appropriate Therapy in the PRAETORIAN Trial” Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBResponse by van der Stuijt et al to Letter Regarding Article, “Efficacy and Safety of Appropriate Shocks and Antitachycardia Pacing in Transvenous and Subcutaneous Implantable Defibrillators: Analysis of All Appropriate Therapy in the PRAETORIAN Trial” Willeke van der Stuijt, Lonneke Smeding, Louise R.A. Olde Nordkamp and Reinoud E. Knops Willeke van der StuijtWilleke van der Stuijt https://orcid.org/0000-0002-2236-3983 Amsterdam UMC, location University of Amsterdam, Amsterdam Cardiovascular Sciences, Department of Clinical and Experimental Cardiology, The Netherlands. Search for more papers by this author , Lonneke SmedingLonneke Smeding https://orcid.org/0000-0002-7558-9011 Amsterdam UMC, location University of Amsterdam, Amsterdam Cardiovascular Sciences, Department of Clinical and Experimental Cardiology, The Netherlands. Search for more papers by this author , Louise R.A. Olde NordkampLouise R.A. Olde Nordkamp Amsterdam UMC, location University of Amsterdam, Amsterdam Cardiovascular Sciences, Department of Clinical and Experimental Cardiology, The Netherlands. Search for more papers by this author and Reinoud E. KnopsReinoud E. Knops https://orcid.org/0000-0002-0772-3573 Amsterdam UMC, location University of Amsterdam, Amsterdam Cardiovascular Sciences, Department of Clinical and Experimental Cardiology, The Netherlands. Search for more papers by this author Originally published25 Jul 2022https://doi.org/10.1161/CIRCULATIONAHA.122.060879Circulation. 2022;146:e10–e11In Response:We appreciate Drs Madias’ interest in our study and are pleased to provide a reply to their comments.Appropriate implantable cardioverter-defibrillator (ICD) therapy can be lifesaving in cases of sustained ventricular arrhythmias. However, inappropriate shocks remain an important complication of ICD therapy and were included in the primary end point of the PRAETORIAN trial (A Prospective, Randomized Comparison of Subcutaneous and Transvenous Implantable Cardioverter Defibrillator Therapy).1 Reported inappropriate shock rates vary, depending on patient population, device type, and programming. As a result of continuous improvements in arrhythmia discrimination algorithms, inappropriate shock rates in the transvenous ICD have been drastically reduced since its introduction.2 It is only reasonable to assume that we will see a corresponding reduction in inappropriate shock rate in the subcutaneous ICD (S-ICD). The UNTOUCHED registry (Understanding Outcomes With the S-ICD in Primary Prevention Patients With Low Ejection Fraction) and EFFORTLESS registry (Evaluation of Factors Impacting Clinical Outcome and Cost Effectiveness of the S-ICD) already demonstrated an apparent reduction in inappropriate shocks with the newest algorithms available in the S-ICD.3,4Patients with heart failure or end-stage renal failure undergoing hemodialysis are at greater risk for fluid shifts, which may affect QRS complexes and might therefore provoke inappropriate shocks. However, to date, these changes have not been shown to increase inappropriate shock rates in the S-ICD. Instead, the UNTOUCHED registry included a large number of patients with New York Heart Association class II/III (888 of 1013 patients) or kidney disease (160 of 1116 patients) but reported the lowest inappropriate shock rate in the S-ICD. In fact, their reported inappropriate shock rate is even lower than the inappropriate shock rates in many contemporary transvenous ICD studies.3 In addition, the authors of EFFORTLESS performed univariable modeling to evaluate any differences in inappropriate shocks in patients with New York Heart Association class I/II compared with class III/IV and in patients with and without kidney disease. They found no statistical differences in the inappropriate shock rate between these subgroups.4Last, when we look only at the inappropriate shock rate, the benefits of the S-ICD are disregarded. The lower complication rate and lower infection rate are a major advantage of the S-ICD, especially in the vulnerable patient groups mentioned by Drs Madias. In addition, it should be emphasized that the transvenous ICD and the S-ICD were equally effective in the prevention of sudden cardiac death in a randomized population.5 Therefore, the S-ICD is a viable treatment option, and the decision for either the transvenous ICD or the S-ICD should be made in a shared decision-making process between patient and physician.Article InformationDisclosures None.FootnotesCirculation is available at www.ahajournals.org/journal/circ