Primary Prevention Implantable Cardioverter Defibrillator Recipients: The Need for Defibrillator Back-Up After an Event-Free First Battery Service-Life

Abstract

The majority of primary prevention ICD patients do not experience VA during first battery service-life. However, a substantial part of these patients does experience appropriate ICD therapy after replacement.

HRS/ACC/AHA Expert Consensus Statement on the Use of Implantable Cardioverter-Defibrillator Therapy in Patients Who Are Not Included or Not Well Represented in Clinical Trials

“…There is evidence that up to 14% of patients who receive an ICD for primary prevention and whose first battery period is uneventful will require device therapy in the following 2.5 years. 35 In patients who undergo ICD implantation for primary prevention, the indication for device therapy persists following MI, particularly if there has been further deterioration of left ventricular function. Similarly, patients who receive device therapy for secondary prevention should be eligible for generator replacement following MI.…”

“…Thus, in patients who previously qualified for the implantation of an ICD for primary prevention of sudden cardiac death and who have undergone revascularization that is unlikely to result in an improvement in LV ejection fraction >0. 35, and who are • In patients within 90 days of revascularization who have previously qualified for the implantation of an ICD for secondary prevention of sudden cardiac death (resuscitated from cardiac arrest due to ventricular tachyarrhythmia) that is unlikely related to myocardial ischemia/injury and have normal left ventricular function, implantation of an ICD is recommended.…”

“…In the Multicenter Automatic Defibrillator Trial (MADIT), 196 patients with prior myocardial infarction, EF ≤0. 35, and inducible nonsuppressible ventricular arrhythmias at electrophysiologic testing were randomized to receive an ICD or medical therapy alone.…”

“…Finally, the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) randomized 2521 patients with an ejection fraction ≤0. 35 and Class II or III heart failure symptoms to ICD therapy, placebo, or amiodarone. In SCD-HeFT slightly more than 50% of patients had cardiac dysfunction and heart failure due to coronary artery disease.…”

Programmed Ventricular Stimulation

“…Although relatively long compared with studies like MADIT-II (mean follow-up, 20 months), there are increasing reports of patients treated with primary prevention ICDs not experiencing an appropriate therapy until after replacement of the initial ICD (ie, >5 years after implantation). 16 It is critical to remember that healing and remodeling after acute MI is an evolutionary process, not a static situation. Patients with low-risk characteristics early after MI may develop recurrent ischemia, heart failure, or other issues that require reassessment of SCD risk during follow-up.…”