Background-Uncertainty remains over optimal antithrombotic treatment of patients with atrial fibrillation presenting with myocardial infarction and/or undergoing percutaneous coronary intervention. We investigated the risk and time frame for bleeding following myocardial infarction/percutaneous coronary intervention in patients with atrial fibrillation according to antithrombotic treatment.
Methods and Results-Patients
Background-Despite wide dissemination, use of automated external defibrillators (AEDs) in community settings is limited.We assessed how AED accessibility affected coverage of cardiac arrests in public locations. Methods and Results-We identified cardiac arrests in public locations (1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)
Background-The benefit of novel implantable cardioverter defibrillator (ICD) programming in reducing inappropriate ICD therapy and mortality was demonstrated in Multicenter Automatic Defibrillator Implantation Trial-Reduce Inappropriate Therapy (MADIT-RIT). However, the cause of mortality reduction remains incompletely evaluated. We aimed to identify factors associated with mortality, with focus on ICD therapy and programming in the MADIT-RIT population. Methods and Results-In MADIT-RIT, 1500 patients with a primary prophylactic indication for ICD or cardiac resynchronization therapy with defibrillator were randomized to 1 of 3 different ICD programming arms: conventional programming (ventricular tachycardia zone ≥170 beats per minute), high-rate programming (ventricular tachycardia zone ≥200 beats per minute), and delayed programming (60-second delay before therapy ≥170 beats per minute). Multivariate Cox models were used to assess the influence of time-dependent appropriate and inappropriate ICD therapy (shock and antitachycardia pacing) and randomized programming arm on all-cause mortality. During an average follow-up of 1.4±0.6 years, 71 of 1500 (5%) patients died: cardiac in 40 patients (56.3%), noncardiac in 23 patients (32.4%), and unknown in 8 patients (11.3%). Appropriate shocks (hazard ratio, 6.32; 95% confidence interval, 3.13-12.75; P<0.001) and inappropriate therapy (hazard ratio, 2.61; 95% confidence interval, 1.28-5.31; P=0.01) were significantly associated with an increased mortality risk. There was no evidence of increased mortality risk in patients who experienced appropriate antitachycardia pacing only (hazard ratio, 1.02; 95% confidence interval, 0.36-2.88; P=0.98). Randomization to conventional programming was identified as an independent predictor of death when compared with patients randomized to high-rate programming (hazard ratio, 2.0; 95% confidence interval, 1.06-3.71; P=0.03). Conclusions-In MADIT-RIT, appropriate shocks, inappropriate ICD therapy, and randomization to conventional ICD programming were independently associated with an increased mortality risk. Appropriate antitachycardia pacing was not related to an adverse outcome. Clinical Trial Registration-URL: clinicaltrials.gov; Unique identifier: NCT00947310.(Circ Arrhythm Electrophysiol. 2014;7:785-792.)
Direct current cardioversion for atrial fibrillation without oral anticoagulation is associated with a high risk of thromboembolism. Notably, the risk is high in the initial period after cardioversion, indicating a hazardous association between DC cardioversion without anticoagulation and thromboembolism.
Background—
Although increased dissemination of automated external defibrillators (AEDs) has been associated with more frequent AED use, the trade-off between the number of deployed AEDs and coverage of cardiac arrests remains unclear. We investigated how volunteer-based AED dissemination affected public cardiac arrest coverage in high- and low-risk areas.
Methods and Results—
All public cardiac arrests (1994–2011) and all registered AEDs (2007–2011) in Copenhagen, Denmark, were identified and geocoded. AED coverage of cardiac arrests was defined as historical arrests ≤100 m from an AED. High-risk areas were defined as those with ≥1 arrest every 2 years and accounted for 1.0% of the total city area. Of 1864 cardiac arrests, 18.0% (n=335) occurred in high-risk areas throughout the study period. From 2007 to 2011, the number of AEDs and the corresponding coverage of cardiac arrests increased from 36 to 552 and from 2.7% to 32.6%, respectively. The corresponding increase for high-risk areas was from 1 to 30 AEDs and coverage from 5.7% to 51.3%, respectively. Since the establishment of the AED network (2007–2011), few arrests (n=55) have occurred ≤100 m from an AED with only 14.5% (n=8) being defibrillated before the arrival of emergency medical services.
Conclusions—
Despite the lack of a coordinated public access defibrillation program, the number of AEDs increased 15-fold with a corresponding increase in cardiac arrest coverage from 2.7% to 32.6% over a 5-year period. The highest increase in coverage was observed in high-risk areas (from 5.7% to 51.3%). AED networks can be used as useful tools to optimize AED placement in community settings.
We convened a multispecialty group of syncope experts to identify the most pressing knowledge gaps and defined a high-priority research agenda to improve the care of patients with syncope in the ED.
C onsiderable clinical decision making revolves around the use of left ventricular ejection fraction (LVEF) for prognosis and for indications for use of both implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT). Guidelines support implantation for CRT for heart failure (HF) patients with LVEF ≤30% with left bundle-branch block (LBBB), sinus rhythm, and New York Heart Association (NYHA) class II, class III, and ambulatory class IV HF symptoms (Class IA recommendation). Similarly, guidelines support implantation of an ICD in postmyocardial infarction patients with LVEF ≤35% (Class IA recommendation) and in nonischemic cardiomyopathy HF Background-Appropriate guideline criteria for use of implantable cardioverter-defibrillators (ICDs) do not take into account potential recovery of left ventricular ejection fraction (LVEF) in patients treated with CRT-defibrillator.
Methods and Results-Patients randomized to CRT-defibrillator from the Multicenter Automatic Defibrillator ImplantationTrial With Cardiac Resynchronization Therapy (MADIT-CRT) trial who survived and had paired echocardiograms at enrollment and at 12 months (n=752) were included. Patients were evaluated by LVEF recovery in 3 groups (LVEF ≤35% [reference], 36%-50%, and >50%) on outcomes of ventricular tachyarrhythmias (VTAs), VTA ≥200 bpm, ICD shock, heart failure or death, and inappropriate ICD therapy by multivariable Cox models. A total of 7.3% achieved LVEF normalization (>50%). The average follow-up was 2.2±0.8 years.
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