Search

Gian Marco Podda,1 Giovanni Casazza,2 Francesco Casella,3 Franca Dipaola,4 Emanuela Scannella,3 Ludovica Tagliabue51Medicina III, Department of Medicine, Surgery and Dentistry, San Paolo Hospital, University of Milan, Milan, Italy; 2Department of Clinical Science, "L. Sacco", University of Milan, Milan, Italy; 3Department of Internal Medicine, L. Sacco Hospital, Milan, Italy; 4Internal Medicine, Istituti Clinici di Perfezionamento Sesto San Giovanni, Italy; 5School of Hygiene and Preventative Medicine, University of Milan, Milan, ItalyBackground: Atrial fibrillation (AF) is the most common sustained arrhythmia. It occurs in 1%–2% of the general population and its prevalence increases with age. Dronedarone, a noniodinated benzofuran similar to amiodarone, was developed as an antiarrhythmic agent for patients with atrial fibrillation. The aim of our systematic review was to critically evaluate randomized controlled trials that compared treatment with dronedarone versus placebo or amiodarone in patients with atrial fibrillation.Methods: Electronic databases (MEDLINE, Embase, and Central) were searched up to November 2011 with no language restrictions. We included randomized controlled trials in which dronedarone was compared to placebo or other drugs in patients with AF. Internal and external validity was assessed.Results: We identified seven papers corresponding to eight randomized controlled trials. The DAFNE, EURIDIS/ADONIS, and ATHENA trials demonstrated a reduction of AF recurrence with dronedarone as compared to placebo in patients with nonpermanent AF. The DIONYSOS study showed that dronedarone is less effective for the prevention of recurrent AF but improved tolerability as compared to amiodarone. Considering patients with permanent AF, the ERATO trial showed that dronedarone had rate-control effects while the PALLAS study was stopped early since stroke, myocardial infarction, systemic embolism, or death from cardiovascular causes were significantly more frequent in subjects treated with dronedarone as compared to placebo. The ANDROMEDA trial included patients with recent hospitalization for heart failure and was terminated early because of excess of deaths in the dronedarone group.Conclusion: Like most antiarrhythmic drugs, dronedarone reduces the recurrence of AF in patients with paroxysmal or persistent AF as compared to placebo. However, relapse rates in the first year of therapy are high. Moreover, dronedarone showed to be less effective than amiodarone. Finally, dronedarone should be avoided in patients with permanent AF and a high risk for cardiovascular events or severe congestive heart failure.Keywords: amiodarone, arrhythmia, cardiovascular events

The interaction of ADP with its platelet receptor P2Y12 plays a crucial role in platelet activation and thrombogenesis. This article reviews the pharmacology and clinical trials of specific antagonists of P2Y12. Clopidogrel is a thienopyridine with proven antithrombotic efficacy, but it has some important drawbacks: (a) it is a pro-drug that needs to be metabolized to its active metabolite; (b) it has a delayed onset and offset of action and (c) there is high inter-individual variability in pharmacological response. Prasugrel is also a thienopyridine, with faster onset of action and a more uniform inhibition of platelet function compared to clopidogrel, accounting for lower incidence of ischemic events in patients with acute coronary syndromes (ACS) undergoing percutaneous coronary intervention (PCI) and higher incidence of both non-CABG-related bleeding complications. Two direct and reversible P2Y12 antagonists, Cangrelor and ticagrelor, are characterized by rapid onset and reversal of platelet inhibition. Cangrelor is not superior to clopidogrel in preventing thrombotic events in patients undergoing PCI. Ticagrelor is superior to clopidogrel in preventing major adverse cardiac events in ACS patients, but, like prasugrel, is associated with a higher frequency of non-CABG-related bleeding complications. A shorter period of drug discontinuation before surgery is necessary in ticagrelor-treated patients compared to clopiodgrel-treated patients to limit the severity of post-surgical bleeding. [ABSTRACT FROM AUTHOR]