Willy Weng1, John Sapp2, Steve Doucette3, Ciorsti MacIntyre2, Christopher Gray2, Martin Gardner2, Amir Abdelwahab2, Ratika Parkash4. 1. Department of Medicine, Dalhousie University, Halifax, Nova Scotia, Canada. 2. Division of Cardiology, QEII Health Sciences Center, Halifax, Nova Scotia, Canada. 3. Research Methods Unit, Department of Community Health and Epidemiology, Dalhousie University, Halifax, Nova Scotia, Canada. 4. Division of Cardiology, QEII Health Sciences Center, Halifax, Nova Scotia, Canada. Electronic address: ratika.parkash@nshealth.ca.
Abstract
OBJECTIVES: This study investigated the benefit of an implantable cardioverter-defibrillator (ICD) generator replacement in patients who did not have an ongoing theoretical indication for ICD therapy at time of replacement. BACKGROUND: Primary prevention ICD therapy is known to reduce mortality in patients with cardiomyopathy and reduced left ventricular systolic function. The data describing outcomes after generator replacement are limited. METHODS: This was a retrospective cohort study following patients implanted with primary prevention ICD therapy from 2002 until 2015 who subsequently received a generator replacement. Patients with an ongoing theoretical indication for ICD therapy were defined as either left ventricular ejection fraction ≤35% or having had prior appropriate ICD therapy. Outcomes were mortality, appropriate ICD therapy and shock, inappropriate shock, and device and lead complications. RESULTS: A total of 614 patients were identified; 173 (28.2%) underwent a generator replacement and were followed for a mean of 2.9 years after replacement; 144 (83.2%) had an ongoing theoretical indication. Patients with no ongoing theoretical indication (n = 29, 16.7%) had lower mortality (hazard ratio [HR]: 0.39, 95% confidence interval [CI]: 0.15-1.00; p = 0.0495), appropriate shock rate (HR: 0.29, 95% CI: 0.09 to 0.96; p = 0.04), and appropriate ICD therapy rate (HR: 0.30, 95% CI: 0.12 to 0.77; p = 0.012) when compared with patients with ongoing theoretical indication. In the entire cohort, there were low rates of inappropriate shock (4.0%), device complication (5.1%), and lead complication (2.3%). CONCLUSIONS: In patients with primary prevention ICD therapy who underwent generator replacement, improved left ventricular ejection fraction and lack of prior appropriate ICD therapy at time of replacement were associated with a lower risk of mortality and incident ventricular arrhythmia.
OBJECTIVES: This study investigated the benefit of an implantable cardioverter-defibrillator (ICD) generator replacement in patients who did not have an ongoing theoretical indication for ICD therapy at time of replacement. BACKGROUND: Primary prevention ICD therapy is known to reduce mortality in patients with cardiomyopathy and reduced left ventricular systolic function. The data describing outcomes after generator replacement are limited. METHODS: This was a retrospective cohort study following patients implanted with primary prevention ICD therapy from 2002 until 2015 who subsequently received a generator replacement. Patients with an ongoing theoretical indication for ICD therapy were defined as either left ventricular ejection fraction ≤35% or having had prior appropriate ICD therapy. Outcomes were mortality, appropriate ICD therapy and shock, inappropriate shock, and device and lead complications. RESULTS: A total of 614 patients were identified; 173 (28.2%) underwent a generator replacement and were followed for a mean of 2.9 years after replacement; 144 (83.2%) had an ongoing theoretical indication. Patients with no ongoing theoretical indication (n = 29, 16.7%) had lower mortality (hazard ratio [HR]: 0.39, 95% confidence interval [CI]: 0.15-1.00; p = 0.0495), appropriate shock rate (HR: 0.29, 95% CI: 0.09 to 0.96; p = 0.04), and appropriate ICD therapy rate (HR: 0.30, 95% CI: 0.12 to 0.77; p = 0.012) when compared with patients with ongoing theoretical indication. In the entire cohort, there were low rates of inappropriate shock (4.0%), device complication (5.1%), and lead complication (2.3%). CONCLUSIONS: In patients with primary prevention ICD therapy who underwent generator replacement, improved left ventricular ejection fraction and lack of prior appropriate ICD therapy at time of replacement were associated with a lower risk of mortality and incident ventricular arrhythmia.
Authors: Daniel J Friedman; Marat Fudim; Robert Overton; Linda K Shaw; Divyang Patel; Sean D Pokorney; Eric J Velazquez; Sana M Al-Khatib Journal: Am Heart J Date: 2018-04-04 Impact factor: 4.749
Authors: Kenneth C Bilchick; Yongfei Wang; Jeptha P Curtis; Ramin Shadman; Todd F Dardas; Inder Anand; Lars H Lund; Ulf Dahlström; Ulrik Sartipy; Wayne C Levy Journal: J Am Heart Assoc Date: 2022-06-29 Impact factor: 6.106