Clinical Risk Stratification for Primary Prevention Implantable Cardioverter Defibrillators. (September 2015)

• Record Type: Journal Article
• Authors: Lee, Douglas S.; Hardy, Judy; Yee, Raymond; Healey, Jeffrey S.; Birnie, David; Simpson, Christopher S.; Crystal, Eugene; Mangat, Iqwal; Nanthakumar, Kumaraswamy; Wang, Xuesong; Krahn, Andrew D.; Dorian, Paul; Austin, Peter C.; Tu, Jack V.
• Is Part Of: Circulation. Volume 8:Number 5(2015)
• Publication Date: 2015-09
• Subjects: Heart failure -- Periodicals; 616.129005
• DOI: 10.1161/CIRCHEARTFAILURE.115.002414
• Languages: English
• ISSNs: 1941-3289

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title>Background—</title> <p>A conceptualized model may be useful for understanding risk stratification of primary prevention implantable cardioverter defibrillators considering the competing risks of appropriate implantable cardioverter defibrillator shock versus mortality.</p> </sec> <sec> <title>Methods and Results—</title> <p>In a prospective, multicenter, population-based cohort with left ventricular ejection fraction ⩽35% referred for primary prevention implantable cardioverter defibrillator, we developed dual risk stratification models to determine the competing risks of appropriate defibrillator shock versus mortality using a Fine-Gray subdistribution hazard model. Among 7020 patients referred, 3445 underwent defibrillator implant (79.7% men, median, 66 years [25th, 75th: 58–73]). During 5918 person-years of follow-up, appropriate shock occurred in 204 patients (3.6 shocks/100 person-years) and 292 died (4.9 deaths/100 person-years). Competing risk predictors of appropriate shock included nonsustained ventricular tachycardia, atrial fibrillation, serum creatinine concentration, digoxin or amiodarone use, and QRS duration near 130-ms peak. One-year cumulative incidence of appropriate shock was 0.9% in the lowest risk category, and 1.7%, 2.5%, 4.9%, and 9.3% in low, intermediate, high, and highest risk groups, respectively. Hazard ratios for appropriate shock ranged from 4.04 to 7.79 in the highest 3 deciles (all <italic>P</italic>⩽0.001 versus lowest risk). Cumulative incidence of 1-year death was 0.6%, 1.9%, 3.3%, 6.2%, and 17.7% in lowest, low, intermediate, high, and highest risk groups, respectively. Mortality hazard ratios ranged from 11.48 to 36.22 in the highest 3 deciles (all <italic>P</italic><0.001 versus lowest risk).</p> </sec> <sec> <title>Conclusions—</title> <p>Simultaneous estimation of risks of appropriate shock and mortality can be performed using clinical variables, providing a potential framework for identification of patients who are unlikely to benefit from prophylactic implantable cardioverter defibrillator.</p> </sec> </abstract>