Pain after subcutaneous ICD implantation: a secondary analysis of the PRAETORIAN-DFT trial

Abstract Background The subcutaneous implantable cardioverter-defibrillator (S-ICD) was developed to prevent complications associated with transvenous leads. Due to its extra-thoracic design, the S-ICD requires more energy to defibrillate the heart resulting in a generator twice the size of the transvenous ICD. Purpose We investigated pain perception after S-ICD implantation and explore predictors for severe pain. Methods The PRAETORIAN-DFT trial included 965 patients undergoing S-ICD implant in 37 centers across Europe, the USA and Israel. Pain was assessed using the Numerical Rating Scale (NRS), with zero indicating no pain and 10 indicating the worst pain possible. NRS was measured before implantation, and 1-4 hours, 5-7 hours, 1 day and 1-4 months after implantation and two questions about the implant experience were asked at follow-up. Logistic regression analysis was used to identify predictors. Implanting physicians were asked their expectations on pain experience. Results In the PRAETORIAN-DFT trial, 24% of patients were female, the mean age was 54±14 years and the most common diagnosis was ischemic cardiomyopathy (45%). The median NRS in the 24 hours after implantation was 4 points. Pain was most frequently experienced at the pocket. There were 262/918 (29%) patients who reported severe pain (NRS≥7) within 24 hours after implantation. Independent predictors for severe pain were female sex (p<0.001, OR 2.23), a procedure duration >48 minutes (p<0.001, OR 1.84) and severe pain at baseline (p=0.026, OR 3.97). Additionally, female sex was an independent predictor for disappointment in pain perception during and after implantation. Physician anticipated NRS and location corresponded with reported pain and females were expected to have more pain by 4/24 physicians. Conclusion In the period surrounding S-ICD implantation, attention should be paid to per- and postoperative analgesia and expectation management in patients with longer procedure duration, severe pre-existing pain, and especially female sex.Percentage of patients experiencing pain