Should We Routinely Place Atrial Leads to Reduce Inappropriate Defibrillator Shocks?

Abstract

Eliminating inappropriate shocks is one of the most vexing challenges for clinicians and patients with implantable cardioverter-defibrillators (ICD). Though a frustration for physicians, inappropriate shocks are a source of despair and fear for patients. Inappropriate shocks often lead to burdensome emergency rooms visits, medication changes or interventions such as atrioventricular node ablation or device modifications. Inappropriate therapies were once seen as an unavoidable price for a life-saving technology. However, we are learning that ICD shocks are associated with significant anxieties and depression, and perhaps reduced survival.1 The associated increase in posttraumatic stress, anxiety, and depression, often brings desperate patients to request that all of their ICD therapies be disabled. Technological advances and the use of ICDs in younger, more vital patients bring the reasonable expectation that inappropriate therapies—especially shocks—should be minimized if not eliminated. Early methods such as simple rate cutoff adjustments and measurements of rate stability have evolved to analysis of the electrogram morphology or the atrioventricular relationship of a given arrhythmia. Two philosophies guide the decision to place an atrial lead to employ atrioventricular detection algorithms. First, some physicians routinely place an atrial lead in their ICD patients to hopefully reduce inappropriate shocks in a population with high rates of atrial arrhythmias. This is usually simple and involves a small increase in procedure time. However, there may be shortand long-term consequences of having these additional components. An analysis of the National Cardiovascular Data Registry (NCDR) demonstrated a 45% increase in complications in patients receiving dual-chamber versus single-chamber ICDs.2 Additionally, as patients live longer with heart disease, they are surviving beyond the lifespan of their ICD components. With this comes lead replacements or extractions for both the inevitable and unexpected breakdown of these components. Recent lead recalls have