Patient reported QOL and EV‐ICD: Response to letter from Kataoka and Imamura (2024)

Our authorship group appreciates the careful consideration of the key issues related to the patient experience posited by Kataoka and Imamura.1 Following publishing of the efficacy and safety data of the extravascular implantable cardioverter defibrillator (EV-ICD),2 our study provided the first available patient reported outcomes (PROs) using both generic and device-specific quality of life (QOL) metrics, and we acknowledge that many questions remain to refine our understanding of the patient experience. Kataoka and Imamura1 queried possible additional group differences in PROs. First, the issue of primary versus secondary prevention indication for implantation (81.8% were primary prevention) and subsequent exposure to ICD shocks was questioned. We compared primary versus secondary indication on the physical and mental subscales of the SF-12 and the composite and subscales of the FPAS, and no differences were found (>0.05). Comparisons between groups with shock and no shock also did not show any differences. Collectively, the existing data does not suggest that device indication or shock exposure impacted PROs. The role of body mass index (BMI) was also raised as a particularly relevant limitation in our study. The average BMI for the full efficacy sample was 28.0 ± 5.6 kg/m2 and our subsamples were 27.8 and 29.3 kg/m2 (completed both SF-12 surveys or completed the FPAS survey, respectively). Kataoka and Imamura question whether there was equitable QOL outcomes by patients with smaller physiques with possible considerations for Asian populations. As we reported,3 BMI scores were significantly different with the smallest BMI group (BMI < 25) reporting a lower mental score on average. Moreover, body image concerns were the highest in the lowest BMI group (BMI < 25) and the youngest (age < 50 years). In contrast, previous reviews with subcutaneous ICDs (S-ICD) in pediatric populations4 has suggested only minor implant modifications may need to be considered, and Vincentini et al. did not find any differences in device acceptance by body habitus.5 The size of the EV-ICD may also be a consideration for shared decision making with respect to the decision of which ICD to implant in which patient. Specifically, the EV-ICD compares favorably in size to the S-ICD (33 vs. 60 cm3, respectively). Device related distress differed between groups and the size of the device may be a factor. The subscale of Device-Related Distress directly queries feelings of disfigurement from the device and this may account for the differences. Finally, the question was raised of selection bias related to the possibility of patients at risk for decreased QOL or patients with smaller body habitus leading to possible avoidance of being enrolled in this study. We do not have any data to refute or accept this limitation as this is the initial sample of patients considering EV-ICDs. However, as noted in the paper,3 we do acknowledge that the process of agreeing to a novel device may induce a degree of positive acceptance bias in patients and in their reporting of outcomes. As a result, we indicated that cautious interpretation of this data is needed until full randomized studies could disentangle these common psychological processes.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.