Latest medical literature on cordarone

Our library of drug research abstracts drawn from the medical literature is updated on a regular schedule, and you can be assured that new cordarone research articles will be listed here shortly after becoming available to us.

Medical research on cordarone

[Amiodaron for treatment of perioperative cardiac arrythmia : A broad spectrum antiarrythmetic agent?]

Anaesthesist. 2008 Aug 14;
Butte N, Böttiger BW, Teschendorf P
Cardiac arrhythmias are a common problem in the perioperative period. The incidence found in the current literature varies depending on the population studied and the definition of arrhythmia used. Overall supraventricular arrhythmias, namely atrial fibrillation, are the most common form. Because of its broad spectrum amiodarone is often used to suppress supraventricular and ventricular arrhythmias. It is believed to be safe for treating patients with severe cardiac disease and it has less proarrhyhmogenic potential than many other antiarrhythmic drugs. However, the use of amiodarone is limited by its cardiac and non-cardiac adverse effects, such as life-threatening bradycardia, pulmonary fibrosis or thyrotoxicosis. According to the guidelines of the American Heart Association, amiodarone can be used to treat atrial fibrillation. Because spontaneous conversion rates in the perioperative setting are high and the advantage of a rhythm control strategy over rate control is questionable, a rate control strategy using less toxic drugs like beta blockers or calcium channel blockers should be preferred in hemodynamically stable patients. The current guidelines of the European Resuscitation Council (ERC) recommend amiodarone to treat hemodynamically stable ventricular tachycardia and in this setting ajmaline is also highly effective. Amiodarone should be administered to patients with cardiac arrest if ventricular tachycardia or ventricular fibrillation persists after three attempts at defibrillation. Dronedarone is a derivate of amiodarone with a similar mechanism of action but with less non-cardiac side effects and is currently being tested in clinical trials. The use of the atrial-specific potassium channel blockers AZD7009 and vernakalant are also being investigated. Furthermore, the role of statins, ACE inhibitors and angiotensin receptor blockers in the prevention of atrial fibrillation has to be evaluated.

Dronedarone:

J Cardiovasc Electrophysiol. 2008 Aug 13;
Laughlin JC, Kowey PR
Dronedarone. Dronedarone is a benzofuran derivative pharmacologically related to amiodarone but without the iodine moiety. It is designed for the treatment of atrial fibrillation and atrial flutter. Historically, amiodarone has proved most effective in maintaining sinus rhythm and has been used safely in patients with advanced heart failure. However, its use has been limited by cumulative and often irreversible organ toxicity, especially in younger patients. Dronedarone was developed in an effort to provide equivalent efficacy and safety with less toxicity. Dronedarone has proved efficacious without toxic or proarrhythmic effects and has minimal side effects, but remaining concerns exist regarding its use in patients with advanced heart failure.

Postoperative oral amiodarone versus oral bisoprolol as prophylaxis against atrial fibrillation after coronary artery bypass graft surgery: A prospective randomized trial.

Int J Cardiol. 2008 Aug 9;
Sleilaty G, Madi-Jebara S, Yazigi A, Haddad F, Hayeck G, Rassi IE, Ashoush R, Jebara V
BACKGROUND: Postoperative atrial fibrillation (AF) occurs in up to 50% of patients undergoing coronary artery bypass (CABG) surgery and is associated with complications. Amiodarone and beta blockers are effective as prophylaxis for AF after CABG. The purpose of this study was to compare oral amiodarone versus oral bisoprolol for prevention of AF after CABG. METHODS: In this randomized study, 200 patients admitted for elective CABG were given oral amiodarone (n=98 patients) or oral bisoprolol (n=102 patients) beginning 6 h after surgery. Amiodarone patients received 15 mg/Kg then 7 mg/Kg/day for one month. Bisoprolol patients received 2.5 mg then 2.5 mg bid indefinitely. RESULTS: Postoperative AF occurred in 15.3% of the patients in the amiodarone group and 12.7% of the patients in the bisoprolol group (p=0.60). Maximal ventricular rate tended to be lower in the bisoprolol group (125+/-6 beats/min) compared with the amiodarone group (144+/-7 beats/min, p=.06). Preoperative beta blockage did not affect AF incidence in either study group. There was no difference between the 2 groups for the onset time of AF episodes, total AF duration, AF recurrence and postoperative length of hospital stay. No serious postoperative complications occurred in the two study groups. Two reversible low cardiac output cases occurred with bisoprolol. CONCLUSIONS: Postoperative oral bisoprolol and amiodarone are equally effective for prophylaxis of AF after CABG. Treatment with bisoprolol resulted in a trend to lower ventricular response rate in AF cases. Both regimens were well tolerated.

Pharmacoepidemiology of QT-interval prolonging drug administration in critically ill patients.

Pharmacoepidemiol Drug Saf. 2008 Aug 11;
Freeman BD, Dixon DJ, Coopersmith CM, Zehnbauer BA, Buchman TG
PURPOSE: Commonly prescribed medications produce QT-prolongation and are associated with torsades de pointes in non-acutely ill patients. We examined patterns of QT-prolonging drug use in critically ill individuals. METHODS: An administrative critical care database was utilized to identify patients receiving drugs associated with QT-interval prolongation or torsades de pointes for >/= 24 hours. RESULTS: Data from 212 016 individuals collected over a 63-month period was examined to identify 6125 patients (2.9%) receiving QT-interval prolonging drugs. These individuals had a mean (+/-SE) age of 63.0 (+/-0.2) years, were predominately male (55.4%) and Caucasian (84.4%), and were exposed to QT-interval prolonging agents for a mean (+/-SE) 53.1 (+/-0.4)% of their ICU length of stay. Respiratory and cardiovascular illnesses were the most common reasons for ICU admission (17.2, 12.0%, respectively). The most frequently administered agents were amiodarone (23.5%), haloperidol (19.8%), and levofloxacin (19.7%); no other single agent accounted for more than 10% of QT-interval prolonging drugs prescribed. Coadministration of QT-prolonging drugs occurred in 1139 patients (18.6%). These patients had higher ICU mortality rate and longer ICU lengths of stay, compared to patients not receiving coadministered drugs (p < 0.001 for both). For patients receiving coadministered drugs, overlap occurred for 71.4 (+/-0.8)% of the time that the drugs were given. Amiodarone coadministration with antibiotics, haloperidol coadministration with antibiotics, and haloperidol coadministration with amiodarone, comprised 15.2, 13.7, and 9.4%, of all coadministered agents, respectively. CONCLUSIONS: QT-prolonging drugs were used in a minority of critically ill patients. Prospective evaluation in the ICU environment is necessary to determine whether administration of these agents is associated with adverse cardiac events comparable to those reported in ambulatory patients. Copyright (c) 2008 John Wiley & Sons, Ltd.

Sudden cardiac death in Chagas' heart disease in the contemporary era.

Int J Cardiol. 2008 Aug 8;
Bestetti RB, Cardinalli-Neto A
This article reviews epidemiology, clinical-morphological aspects, and primary and secondary prevention of sudden cardiac death in patients with chronic Chagas' heart disease in the current era. Chagas' disease patients with life-threatening ventricular tachyarrhythmias are at risk of sudden cardiac death. No evidence-based support is available for guiding prophylaxis of sudden cardiac death in patients with this condition. Therefore, measurements for sudden cardiac death prevention in Chagas' disease patients have been derived from data obtained in non-Chagas' disease patients as well as on expertise of physicians dealing with this disorder in areas where Chagas' disease is endemic. For primary prevention, therefore, we suggest that patients with non-sustained VT be referred to programmed ventricular stimulation. Patients with inducible VT will be better treated with Implantable Cardioverter-Defibrillator (ICD) than with amiodarone therapy. For secondary prevention, we suggest that patients with malignant ventricular tachyarrhythmias with hemodynamic instability receive ICD therapy. For patients with life-threatening ventricular arrhythmias and no hemodynamic instability, however, secondary prevention can be accomplished with ICD therapy or catheter ablation in those with a left ventricular ejection fraction (LVEF) of 30% or less, and with electrophysiologic testing-guided drug therapy or empiric treatment with amiodarone in those with a LVEF of 30% or high.

Routine ganglionic plexi ablation during Maze procedure improves hospital and early follow-up results of mitral surgery.

J Thorac Cardiovasc Surg. 2008 Aug; 136(2): 408-18
Onorati F, Curcio A, Santarpino G, Torella D, Mastroroberto P, Tucci L, Indolfi C, Renzulli A
OBJECTIVE: Ganglionic plexi are claimed to be potentially responsible for atrial fibrillation. We evaluated whether ganglionic plexi isolation improves the results of the Maze procedure during mitral valve surgery. METHODS: A total of 75 patients with atrial fibrillation underwent radiofrequency ablation during mitral valve surgery without (group A) or with (group B) ganglionic plexi ablation with bipolar radiofrequency plus fat pad resection along the Waterston groove, left pulmonary veins, and Marshall's ligament. Ganglionic plexi were intraoperatively mapped, and fat pad specimens were sectioned and analyzed. Hospital and follow-up results were recorded. Amiodarone was discontinued at the sixth month. RESULTS: Active ganglionic plexi were mainly located in the upper parts of fat pads. Active specimens demonstrated more ganglionic plexi than inactive specimens (P

Cardiovascular drugs and bone.

Curr Drug Saf. 2008 Sep; 3(3): 178-84
Rejnmark L
Cardiovascular diseases are common and occur mainly in the elderly in whom osteoporotic fractures also are very common. Because of this, it is of importance to establish whether drugs used in the treatment of cardiovascular diseases affect bone, in order to minimise any possible adverse effects. In the majority of studies, treatment with thiazide diuretics, statins, digoxin, angiotensin-converting enzyme (ACE)-inhibitors, and organic nitrates have not been associated with harmful effects on bone. On the contrary, treatment with these drugs may improve bone strength but because there is a lack of randomised controlled trials (RCTs) with fracture as a primary outcome measure, these drugs should not be prescribed for fracture prevention. In RCTs, treatment with loop diuretics have been shown to increase plasma levels of parathyroid hormone and decrease bone mineral density. In epidemiological studies, treatment with loop diuretics as well as treatment with amiodarone has been associated with an increased risk of fracture. In view of the conflicting results from published studies, no conclusions can be drawn on potential bone effects of treatment with oral anticoagulants, beta-blockers, and calcium channel blockers.

Right pectoral implantable cardioverter defibrillators: role of the proximal (SVC) coil.

Pacing Clin Electrophysiol. 2008 Aug; 31(8): 1025-35
Varma N, Efimov I
INTRODUCTION: Increased defibrillation thresholds (DFTs) with right active pectoral implantable cardioverter defibrillators (ICDs) and/or right proximal coils (SVC) are attributed to poorer vector. However, SVC affects impedance, current flow, and shock waveform phase duration (PD), which exert independent DFT effects. Objective:Compare DFTs and shock characteristics in SVC On with SVC Off in right ICDs. METHODS AND RESULTS: DFT+ testing (n = 42, 62% males, 62 +/-15 years, left ventricular ejection fraction (LVEF) 26 +/- 11%, ischemic cardiomyopathy 65%, amiodarone 26%) revealed >20% incidence of high DFT (>20J) . Dilated cardiomyopathy and amiodarone increased DFT. Individual impedance variability (25-74 Omega) generated a wide PD range (2.6-8.7 ms). Overall, SVC On reduced impedance by 33% (from 54 +/- 10 to 35 +/- 5Omega, P< 0.0001), and shortened PD (from 5.45 +/- 1.20 to 3.67 +/- 0.74 ms, P< 0.01). SVC On affected DFTs in 19/42 (45%) patients. SVC On was beneficial in 12/19. PD shortened but current flow remained unaltered. (In these, SVC Off impedance was >45Omega and PD >5 ms.) SVC On was detrimental in 7/19 despite increasing current flow. In these, PD shortened excessively (median 2.9 ms) because impedance was low (31 +/- 4Omega). In 3/6 cases with DFTs >20 J in both SVC On and Off, PD optimization reduced DFT. Overall, selection of best SVC configuration or deliberate PD programming yielded DFTs 90% patients, reducing need for system modification to

[Effects of pretreatment with amiodarone infusion in patients with persistent atrial fibrillation submitted to external electrical cardioversion: a single center experience]

G Ital Cardiol (Rome). 2008 Jul; 9(7): 504-8
Maffè S, Paffoni P, Perucca A, Dellavesa P, Parravicini U, Nicali R, Bielli M, Paino AM, Signorotti F, Franchetti Pardo N, Zenone F, Zanetta M
BACKGROUND: Several studies demonstrated the efficacy of amiodarone pretreatment in achieving bet-ter outcomes after electrical cardioversion of atrial fibrillation. In the majority of cases, oral amiodarone for at least 1 month was administered, with the result of lengthening of pre-cardioversion time. Only one study in the literature reported high-dose amiodarone infusion, showing an increase in the incidence of slow arrhythmias. The aim of this study was to test the efficacy of pretreatment infusion of a single dose of amiodarone few hours before electrical cardioversion in restoring sinus rhythm and reducing the incidence of early arrhythmic recurrences. METHODS: The study was retrospective. We analyzed a population of 155 patients with persistent atrial fibrillation, from May 2003 to November 2005. The first group of 86 patients was treated with amiodarone at the dose of 4 mg/kg in 30 min, few hours before electrical cardioversion; the second group of 69 patients was treated with electrical cardioversion without pharmacological pretreatment. The two groups were homogeneous for age, sex, coronary artery disease, duration of arrhythmia, atrial dimensions, left ventricular ejection fraction, and paddle position for electrical cardioversion. RESULTS: There were no significant differences between the two groups in terms of efficacy of cardioversion (95.3 vs 91.3%, p = NS). Pretreatment with bolus of amiodarone significantly reduced the incidence of immediate recurrence (3.5 vs 17.4%, p < 0.05) and the mix of immediate and early recurrence (19.7 vs 33.3%, p < 0.05). There were no significant differences in the incidence of late recurrences (17.4 vs 13%, p = NS). There were no significant bradyarrhythmias in the two groups. Amiodarone pretreatment did not reduce energy delivery to obtain cardioversion. CONCLUSIONS: Amiodarone pretreatment with intravenous bolus few hours before electrical cardioversion reduces short-term recurrences of atrial fibrillation. It does not reduce energy delivery of electrical cardioversion and does not increase the incidence of slow arrhythmias. Randomized prospective studies are warranted to confirm these findings.

Re: Combined therapy with carvedilol and amiodarone is more effective in improving cardiac symptoms, function, and sympathetic nerve activity in patients with dilated cardiomyopathy: comparison with carvedilol therapy alone.

J Nucl Cardiol. 2008 Jul-Aug; 15(4): 604
Koracevic G