Implantable Cardioverter-Defibrillator Registry Risk Score Models for Acute Procedural Complications or Death After Implantable Cardioverter-Defibrillator Implantation

Background— Patients undergoing implantable cardioverter-defibrillator (ICD) implantation are at risk of postprocedural complications. However, we do not have a risk stratification schema to identify patients at high and low risk of adverse events. Methods and Results— We analyzed data from 268 701 ICD implants submitted to the ICD Registry and developed logistic regression models to identify variables most strongly associated with the risk of acute complications and/or in-hospital death. Overall, 3.2% of the population experienced an adverse event. A simple risk score consisting of 10 readily available variables successfully identified patients at high and low risk of complications. The variables included in the score and assigned points included: age ≥70 years (1 point), female (2 points), New York Heart Association class III (1 point) or IV (3 points), atrial fibrillation (1 point), prior valve surgery (3 points), chronic lung disease (2 points), blood urea nitrogen >30 (2 points), reimplantation for reasons other than battery change (6 points), ICD type dual chamber (2 points) or biventricular (4 points), and nonelective ICD implant (3 points). The risk of any in-hospital complication increased from 0.6% among patients with a score of ⩽5 (8.4% of the population) to 8.4% among patients with ≥19 risk points (3.9% of the population). Conclusions— A simple risk score consisting of readily available clinical variables can identify high- and low-risk subsets of patients undergoing ICD implantation. This information can guide the physician in patient selection and determining the intensity of care required post procedure.