Inappropriate Implantable Cardioverter-Defibrillator Shocks

Abstract

In a large cohort of ICD patients, inappropriate shocks were common. The most important finding is the association between inappropriate shocks and mortality, independent of interim appropriate shocks.

2015 HRS/EHRA/APHRS/SOLAECE expert consensus statement on optimal implantable cardioverter-defibrillator programming and testing

“…Although therapies delivered by the ICD can abort SCD, appropriate and inappropriate ICD shocks have been associated with a considerable increase in the risk of mortality [82,83,[155][156][157][158]. In the Sudden Cardiac Death in Heart Failure Trial (SCDHeFT), the risk of mortality was 5-fold higher in patients who received appropriate ICD shocks and 2-fold higher in patients who received inappropriate shocks [83].…”

Wearable Cardioverter-Defibrillator Therapy for the Prevention of Sudden Cardiac Death

“…46,48,57 In contrast, ICD shock rates have been demonstrated to be 13% over 41 months. 59 In addition to the overall published national experience, 48 several observational studies in selected patient groups and single centers have been reported. In a manufacturer's database of WCD use in 8453 patients within 90 days of MI (median time from AMI to WCD, 16 days; 62% of patients revascularized; 77% with LVEF ≤0.30), 1.6% of the patients received appropriate shocks.…”

Device Therapies Among Patients Receiving Primary Prevention Implantable Cardioverter‐Defibrillators in the Cardiovascular Research Network

“…Atrial fibrillation, a risk factor for inappropriate therapies in previous studies,22, 38, 39 was associated with a >2‐fold higher risk for inappropriate therapy during follow‐up. An understanding of the magnitude of this risk, as well as the impact of evidence‐based therapies (eg, AV nodal blockers) on this risk, will be informative to patients with atrial fibrillation considering ICD therapy.…”

“…The mechanisms for this are unclear, but men may be more likely to develop malignant ventricular arrhythmias compared with women, which may also explain greater ICD efficacy observed in men in some studies 37. The relation between younger age and inappropriate therapies has been reported in some,38, 39 but not in other,22 studies, and may result from more robust atrioventricular conduction of supraventricular arrhythmias among younger patients. The considerably lower risk of appropriate therapy among Hispanic patients is novel and warrants further investigation, especially given reports of similar survival associated with ICD therapy in Hispanic and non‐Hispanic white patients 40…”