DRIVING RESTRICTION AND EARLY ARRHYTHMIAS IN PATIENTS RECEIVING A SUBCUTANEOUS IMPLANTABLE CARDIOVERTER DEFIBRILLATOR (DREAM SICD STUDY)

Abstract

BACKGROUND Subcutaneous defibrillators (SICD) are being used increasingly for selected patients. Although there are established Canadian driving guidelines post transvenous ICD implantation, none exist for SICDs. The purpose of this study is to evaluate the rate of appropriate and inappropriate therapies and sudden cardiac incapacitation (SCI) after implantation of a SICD in contemporary practice. These data will help ascertain current driving guidelines in Canada following SICD implantation. The primary endpoint was incidence of appropriate and inappropriate ICD therapy within 7 days, 14 days, 30 days, 60 days, 90 days, 180 days and one-year post SICD implantation. The secondary variable was annualized risk of harm (ARH) while driving; ARH < 0.00005 while driving is considered acceptable in Canada. METHODS AND RESULTS We performed retrospective chart reviews of consecutive patients who received a SICD at eight Canadian centers between January 1st, 2016 and May 31st, 2020, including 198 patients in the final analysis. Both primary and secondary prevention SICDs were included. We reviewed device clinic electronic medical records and charts from immediate post-implant and subsequent follow-up visits. The baseline patient demographics are described in table 1. The overall incidence of syncope was 2.5%. The adjusted incidence rate of any ICD therapy and ARH while driving remained below the acceptable risk of harm for secondary prevention patients, except in the first 7 days post implantation (Figure 2a). The ARH while driving remained below the acceptable risk for primary prevention patients at all of the time periods (Figure 2b) till 12 months of follow up. CONCLUSION The rate of appropriate ICD therapy in a contemporary patient population implanted with an SICD is very low and the ARH while driving remains below acceptable harm threshold, except in first seven days for secondary prevention population. To our knowledge, this is the first study to assess the risk of harm while driving in a contemporary patient population with SICDs. Subcutaneous defibrillators (SICD) are being used increasingly for selected patients. Although there are established Canadian driving guidelines post transvenous ICD implantation, none exist for SICDs. The purpose of this study is to evaluate the rate of appropriate and inappropriate therapies and sudden cardiac incapacitation (SCI) after implantation of a SICD in contemporary practice. These data will help ascertain current driving guidelines in Canada following SICD implantation. The primary endpoint was incidence of appropriate and inappropriate ICD therapy within 7 days, 14 days, 30 days, 60 days, 90 days, 180 days and one-year post SICD implantation. The secondary variable was annualized risk of harm (ARH) while driving; ARH < 0.00005 while driving is considered acceptable in Canada. We performed retrospective chart reviews of consecutive patients who received a SICD at eight Canadian centers between January 1st, 2016 and May 31st, 2020, including 198 patients in the final analysis. Both primary and secondary prevention SICDs were included. We reviewed device clinic electronic medical records and charts from immediate post-implant and subsequent follow-up visits. The baseline patient demographics are described in table 1. The overall incidence of syncope was 2.5%. The adjusted incidence rate of any ICD therapy and ARH while driving remained below the acceptable risk of harm for secondary prevention patients, except in the first 7 days post implantation (Figure 2a). The ARH while driving remained below the acceptable risk for primary prevention patients at all of the time periods (Figure 2b) till 12 months of follow up. The rate of appropriate ICD therapy in a contemporary patient population implanted with an SICD is very low and the ARH while driving remains below acceptable harm threshold, except in first seven days for secondary prevention population. To our knowledge, this is the first study to assess the risk of harm while driving in a contemporary patient population with SICDs.