Inappropriate implantable cardioverter defibrillator shocks—incidence, effect, and implications for driver licensing

Abstract

PurposePatients with implantable cardioverter defibrillators (ICDs) have an ongoing risk of sudden incapacitation that may cause traffic accidents. However, there are limited data on the magnitude of this risk after inappropriate ICD therapies. We studied the rate of syncope associated with inappropriate ICD therapies to provide a scientific basis for formulating driving restrictions.MethodsInappropriate ICD therapy event data between 1997 and 2014 from 50 Japanese institutions were analyzed retrospectively. The annual risk of harm (RH) to others posed by a driver with an ICD was calculated for private driving habits. We used a commonly employed annual RH to others of 5 in 100,000 (0.005%) as an acceptable risk threshold.ResultsOf the 4089 patients, 772 inappropriate ICD therapies occurred in 417 patients (age 61 ± 15 years, 74% male, and 65% secondary prevention). Patients experiencing inappropriate therapies had a mean number of 1.8 ± 1.5 therapy episodes during a median follow-up period of 3.9 years. No significant differences were found in the age, sex, or number of inappropriate therapies between patients receiving ICDs for primary or secondary prevention. Only three patients (0.7%) experienced syncope associated with inappropriate therapies. The maximum annual RH to others after the first therapy in primary and secondary prevention patients was calculated to be 0.11 in 100,000 and 0.12 in 100,000, respectively.ConclusionsWe found that the annual RH from driving was far below the commonly cited acceptable risk threshold. Our data provide useful information to supplement current recommendations on driving restrictions in ICD patients with private driving habits.Electronic supplementary materialThe online version of this article (doi:10.1007/s10840-017-0272-4) contains supplementary material, which is available to authorized users.

Predictors of appropriate ICD therapy in Japanese patients with structural heart diseases: A major role of prior sustained ventricular tachycardia in secondary prevention

“…In Japan, the proportion of patients with IHD in patients implanted with an ICD/CRT-D was reported to be 31%, and cardiomyopathy and valvular heart disease were etiologies of the heart disease in 66% and 3% of the patients, respectively. 13 In the present study, rates of appropriate ICD/CRT-D therapy were 49% at 3 years and 54% at 5 years (Figure 1), and the rates are similar to the rates in earlier studies despite the difference in the proportion of patients with IHD in the study subjects. [8][9][10][11] It is notable that there was no significant difference between the rates of appropriate therapy in patients with IHD and patients with non-IHD SHD in the present study ( Figure 2).…”

“…In their studies, the rates of appropriate ICD therapy were 59% at 5 years and 65% at 10 years. In Japan, the proportion of patients with IHD in patients implanted with an ICD/CRT‐D was reported to be 31%, and cardiomyopathy and valvular heart disease were etiologies of the heart disease in 66% and 3% of the patients, respectively . In the present study, rates of appropriate ICD/CRT‐D therapy were 49% at 3 years and 54% at 5 years (Figure ), and the rates are similar to the rates in earlier studies despite the difference in the proportion of patients with IHD in the study subjects .…”

“…The rate of appropriate therapy by ICD insertion has been reported to be higher in patients in whom the device was implanted for secondary prevention than in patients in whom the device was implanted for primary prevention . Clinical trials on ICD therapy have been mainly conducted in European countries and the United States, where most cases of underlying heart disease are ischemic heart disease, and thus, the findings may not be necessarily applicable to countries with different prevalences of heart diseases such as Japan, where SHD in 51%‐69% of candidates for ICD therapy is cardiomyopathy . In the Japanese guidelines of ICD implantation for secondary prevention, both documented ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in SHD are class I indication.…”

“…[4][5][6][7][8][9][10][11] Clinical trials on ICD therapy have been mainly conducted in European countries and the United States, where most cases of underlying heart disease are ischemic heart disease, [1][2][3]5,[7][8][9][10][11] and thus, the findings may not be necessarily applicable to countries with different prevalences of heart diseases such as Japan, where SHD in 51%-69% of candidates for ICD therapy is cardiomyopathy. [12][13][14][15] In the Japanese guidelines of ICD implantation for secondary prevention, 16 both documented ventricular fibrillation (VF) and hemodynamically unstable ventricular tachycardia (VT) in SHD are class I indication. However, it is unclear whether the rate of appropriate therapy differs depending on the type of prior ventricular arrhythmia or other clinical parameters.…”

A Decision Tree-Based Survival Analysis of Patients with a History of Inappropriate Implantable Cardioverter-Defibrillator Therapy

“…I mplantable cardioverter-defibrillators (ICDs) improve survival in patients who are at risk of sudden cardiac death. 1) However, inappropriate ICD therapy for nonventricular arrhythmias is a common occurrence [2][3][4][5] and has been linked to negative psychological effects and a diminished quality of life. 6) Profound anxiety and panic reactions focused on the fear of future ICD therapy are the most frequent manifestations of psychopathology.…”