Importance of beta-blocker dose in
prevention of ventricular tachyarrhythmias, heart failure hospitalizations, and death in primary prevention implantable cardioverter-defibrillator recipients:
a Danish nationwide cohort study
The use of guideline recommended beta-blocker therapy in primary prevention implantable cardioverter defibrillator patients: insight from Danish nationwide registers.
We aimed to examine the use of guideline recommended beta-blocker therapy prior to and after primary prevention implantable cardioverter defibrillator (ICD) implantation in a ‘real-life’ setting.
METHODS AND RESULTS:
From the Danish Pacemaker and ICD Registry we identified all 1st-time primary prevention ICD and cardiac resynchronization therapy defibrillator (CRT-D) implantations in Denmark from 2007-12 (n = 2935). Use of beta-blocker, type and dose was acquired through the Danish Prescription Registry. According to guideline recommendations, we defined target daily doses as ≥50 mg carvedilol and ≥200 mg metoprolol. Prior to implantation 2427 of 2935 (83%) patients received beta-blocker therapy, with 2166 patients (89%) having initiated treatment 3 months or more prior to implantation. The majority of patients was prescribed carvedilol (52%) or metoprolol (41%). Patients on carvedilol reached target dosages more frequently than patients on metoprolol, with 39% of patients on carvedilol and 26% of patients on metoprolol at the time of implantation (P < 0.001 for all time-points). Increase in proportion of patients reaching target daily doses was observed for both carvedilol and metoprolol after ICD implantation. Carvedilol treatment was a strong predictor for being on target dose of BB at time of implant, as was treatment with angiotensin-converting enzyme inhibitors and/or spironolactone, no history of myocardial infarction, younger age and less pronounced heart failure symptoms.
In a real-life setting of primary prevention ICD patients, 39% and 26% of patients were titrated to optimal target dose of carvedilol or metoprolol prior to implantation. A higher proportion of patients on carvedilol reached target dose, as compared with metoprolol.
The impact of co‐morbidity burden on appropriate implantable cardioverter defibrillator therapy and all‐cause mortality: insight from Danish nationwide clinical registers
- Department of Cardiology, Herlev-Gentofte University Hospitals, Copenhagen, Denmark.
- National Institute of Public Health, Copenhagen, Denmark.
- Department of Cardiology, University of Southern Denmark, Odense, Denmark.
- The Danish Heart Foundation.
- Department of Cardiology, Odense University Hospital, Odense, Denmark.
- Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.
- Department of Cardiology, Rigshospitalet, Copenhagen, Denmark.
- Department of Cardiology, Aalborg University Hospital, Aalborg, Denmark.
In a nationwide cohort of primary (PP-ICD) and secondary prevention (SP-ICD) implantable cardioverter defibrillator (ICD) patients, we aimed to investigate the association between co-morbidity burden and risk of appropriate ICD therapy and mortality.
METHODS AND RESULTS:
We identified all patients >18 years, implanted with first-time PP-ICD (n = 1873) or SP-ICD (n = 2461) in Denmark from 2007 to 2012. Co-morbidity was identified in administrative registers of hospitalization and drug prescription from pharmacies. Co-morbidity burden was defined as the number of pre-existing non-ICD indication-related co-morbidities including atrial fibrillation, diabetes, chronic obstructive pulmonary disease, chronic renal disease, liver disease, cancer, chronic psychiatric disease, and peripheral and/or cerebrovascular disease, and divided into four groups (co-morbidity burden 0, 1, 2, and ≥3). Through Cox models, we assessed the impact of co-morbidity burden on appropriate ICD therapy and mortality. Increasing co-morbidity burden was not associated with increased risk of appropriate therapy, irrespective of implant indication [all hazard ratios (HRs) 1.0-1.4, P = NS]. Using no co-morbidities as reference, increasing co-morbidity burden was associated with increased mortality risk in PP-ICD patients (co-morbidity burden 1, HR 2.1; comorbidity burden 2, HR 3.7; co-morbidity burden ≥3, HR 6.6) (all P < 0.001) and SP-ICD patients (co-morbidity burden 1, HR 2.2; co-morbidity burden 2, HR 3.8; co-morbidity burden ≥3, HR 5.8). With increasing co-morbidity burden, an increasing frequency of patients died without having utilized their device, with 72% PP-ICD and 45% SP-ICD patients with co-morbidity burden ≥3 dying without prior appropriate ICD therapy.
Increasing co-morbidity burden was not associated with increased risk of appropriate ICD therapy. With increasing co-morbidity burden, mortality increased, and a higher proportion of patients died, without ever having utilized their device.