The PRAETORIAN XL study is an observational sub-study of one of the pre-defined secondary endpoints with an extended follow-up duration.

Since the introduction of the S-ICD new algorithms have been introduced resulting in a decreased incidence of inappropriate shocks, making these less important in the evaluation of S-ICD treatment. However, the expected benefit of the subcutaneous position of the S-ICD with regards to device-related complications can only be demonstrated during a longer follow-up period, as transvenous lead-related complications occur during long term follow-up.

The complication rate of the S-ICD is expected to stabilize after initial acute complications. Acute complications such as lead dislodgement are clinically less severe as these can often be easily resolved. In contrast, chronic (lead) complications that are seen in the TV-ICD therapy impose a greater risk for patients as they often involve systemic infection with endocarditis and/or extraction in a tertiary extraction center with a significant risk of morbidity and/or mortality. The PRAETORIAN trial population provides a unique opportunity to observe long-term performance of the S-ICD, as it is highly unlikely that a new trial that randomizes between S-ICD and TV-ICD will be performed with current available evidence about benefits of the S-ICD in certain patient populations.

Objective                                                                                                                                            The primary objective of PRAETORIN XL is to study whether the S-ICD is superior to the TV-ICD with respect to acute and chronic device-related complications. Secondary analysis will study among others with S-ICD implant position (PRAETORIAN score), appropriate and inappropriate therapy, mortality, MACE and cardiac decompensation.