Psychological Effects of Implantable Cardioverter-Defibrillator Leads under Advisory

Abstract

Automatic implantable cardioverter-defibrillators (ICDs) are standard therapy for patients at high risk of sudden cardiac death. Device implantation is a stressful event that has been associated with patient and anticipatory anxiety. While the psychological effects of normally functioning ICDs are known, only a dearth of literature evaluates how a warning about the potential for malfunction of an ICD lead, related to a device advisory, influences the degree of psychological distress. These effects are evaluated in a patient population with the Medtronic Sprint Fidelis defibrillation lead 6949 (Medtronic, Minneapolis, MN, USA). A sample of 413 patients were studied. Groups included 158 with an advisory Medtronic 6949 and 255 with an ICD that had no current advisories. Patients were administered a validated disease-specific metric assessing concerns over ICDs, as well as a demographics questionnaire. The primary outcome was the total score on the ICD concerns (ICDC). Analysis was with one-way Analysis of Variance with preplanned orthogonal contrasts and multivariate regression. The advisory group tended to have higher numbers of high school and college graduates. The average length of device implant in the nonadvisory group was higher at 4.29 years versus 3.99 years in the advisory group (t = 0.901, P ≤ 0.5). A higher percentage of those with an advisory experienced more shocks (39% vs 32%; z =-1.51, P ≤ 0.5). Average ICDC scores in the advisory group with previous shock were significantly higher than in the nonadvisory group with prior shock ([27.7 standard deviation (SD) ± 14.5] vs [18.5 SD ± 12.5], P = 0.0001) . Average ICDC score in the advisory group without shock was also significantly elevated compared to the nonadvisory group (18.5 SD ± 14.5 vs 10.8, SD ± 12.5, P = 0.0001). There was a significant effect of having an advisory on total ICDC scores (F = 21.32, P ≤ 0.0001). History of shock also significantly increased total ICDC scores (F = 20.07, P ≤ 0.0001). In multivariate regression, presence of Fidelis lead and history of shock were predictors for increased ICDC scores (R(2) = 0.158, F = 38.88, P = 0.0001). When controlling for shock history, presence of Fidelis lead remained an independent predictor of elevated ICDC scores (R(2) = 0.125, F = 59.30, P ≤ 0.0001). Our study attempts to address some of the psychological differences between participants with advisory and nonadvisory leads. Higher scores on the ICDC were found in our advisory group. While statistically significant, it is entirely unclear if these scale elevations are clinically significant or if directed counseling at this stage may reduce these elevations. This raises the suspicion that directed counseling be undertaken for patients with future advisories.