New strategies and recommendations to optimize subcutaneous ICD therapy

Chapter 2 of this thesis establishes the noninferiority of the S-ICD compared to the transvenous ICD, regarding device-related complications and inappropriate shocks. In chapter 3, we find that S-ICD patients had a similar number of appropriate shocks as TV-ICD patients, despite the absence of the capability to deliver antitachycardia pacing (ATP). First and final shock efficacy showed no significant difference between both groups. ATP was successful in approximately half of all monomorphic ventricular tachyhcardias, but accelerated the arrhythmia in 9.4%.
Chapter 4 explores the experiences of female S-ICD patients, highlighting the discomfort caused by interference of the bra and their preference for a smaller S-ICD generator. Chapter 5 reveals that labor does not trigger ventricular arrhythmias or inappropriate ICD therapy, with most patients opting to keep their ICD active during labor.
Chapter 6 showcases the high success rate in defibrillation testing during elective S-ICD generator replacements and the low complication rate during follow-up. Chapter 7 demonstrates that defibrillation thresholds in S-ICD replacements are lower than initially reported in de novo implants. Despite an increase in high-voltage impedance over time, most S-ICD patients achieved successful defibrillation at ≤30J during replacement.
Chapter 8 explains that high-voltage impedance rises mainly in the presence of adipose tissue and air between defibrillator components, emphasizing the need for careful positioning. Chapter 9 acknowledges defibrillation testing risks and challenges, emphasizing the need for a comprehensive understanding of factors influencing defibrillation success.