Amiodarone ; administration & dosage ; Anti-Arrhythmia Agents ; administration & dosage ; Atrial Fibrillation ; drug therapy ; Heart Valve Diseases ; drug therapy ; Humans ; Quality of Life ; Rheumatic Heart Disease ; drug therapy

BACKGROUNDLong-term maintenance of sinus rhythm after successful conversion of chronic atrial fibrillation (CAF), often ameliorates patients' symptoms, reduces the risk of ischemic stroke and improves cardiovascular hemodynamics. This prospective study aims to evaluate the long-term efficacy and safety of very low-dose amiodarone (100 mg daily) for the maintenance of sinus rhythm after successful direct-current (DC) cardioversion in patients with CAF and rheumatic heart disease (RHD) post intervention.

METHODSThis study was a randomized prospective trial. One day after successful DC cardioversion (remained normal sinus rhythm) in patients with CAF and RHD post intervention for more than six months and adequate anticoagulation, all were randomly administered either amiodarone 200 mg daily in group A or amiodarone 100 mg daily in group B.

RESULTSA total of 76 patients (40 men and 36 women) were examined from February 1998 to December 1999. The mean age of the patients was (66 +/- 10) years, and the mean follow-up was (67 +/- 8) months (range 61 to 84 months). Actuarial rates of the maintenance of sinus rhythm were similar in the two groups after 5 years of follow-up. Four patients (11%) in group A but none in group B experienced significant adverse effects that necessitated withdrawal of amiodarone. No death occurred during the study period.

CONCLUSIONA very low dose of amiodarone results in adequate long-term efficacy and is safe for maintaining sinus rhythm in patients with CAF and RHD post intervention after successful DC cardioversion.

Aged ; Amiodarone ; administration & dosage ; adverse effects ; Anti-Arrhythmia Agents ; administration & dosage ; Arrhythmia, Sinus ; drug therapy ; Atrial Fibrillation ; drug therapy ; physiopathology ; Chronic Disease ; Cohort Studies ; Electric Countershock ; methods ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies

OBJECTIVETo probe the feasibility of acupuncture in conversion of paroxymal atrial fibrillation and atrial flutter.

METHODSEighty cases of atrial fibrillation and atrial flutter were randomly divided into 2 groups, a treatment group and a control group, 40 cases in each group. The treatment group were treated with acupuncture at Neiguan (PC 6), Shenmen (HT 7), Danzhong (CV 17) and others, and the control group with intravenous injection of amiodarone. The cardiac rhythms and side effects were observed in the two groups.

RESULTSThe total effective rate of 85.0% in the treatment group was better than 67.5% in the control group (P < 0.01). The average conversion time was (39.6 +/- 13.7) min in the treatment group and (50.1 +/- 14.8) min in the control group with a significant difference between the two groups (P < 0.01). No adverse effect was found in the treatment group.

CONCLUSIONAcupuncture is a safe and effective therapy for conversion of paroxymal atrial fibrillation and atrial flutter.

Acupuncture Therapy ; Aged ; Amiodarone ; administration & dosage ; therapeutic use ; Anti-Arrhythmia Agents ; therapeutic use ; Atrial Fibrillation ; therapy ; Atrial Flutter ; therapy ; Female ; Humans ; Injections, Intravenous ; Male ; Middle Aged

OBJECTIVETo study the plasma concentration-time curve, pharmacokinetic parameters and bioavilability of oxymatrine-phospholipid complex and to compare with oxymatrine in rats.

METHODRats were given oxymatrine-phospholipid 100 mg x kg(-1). Blood samples were collected at different times after oral administration. The internal standard was cimetidine. Protein in plasma was precipitated with merhanol and centrifuged at high speed. The supernatant was directly injected and assayed by CE method. The running buffer was 0.04 mol x L(-1) Tris-10 mmol x L(-1) sodium phosphate monobasic-40% isopropanol pH to 7.6 with phosphoric acid. The wavelength of detection was 205 nm.

RESULTThe AUC of oxymatrine and oxymatrine-phospholipid complex were 4.52 mg x mL(-1) x h(-1) and 6.21 mg x mL(-1) x h(-1), respectively. The oxymatrine-phospholipid bioavailability enhanced 1.4 times.

CONCLUSIONIt is concluded that after oral administration of oxymatrine-phospholipid complex in rats the bioavailability of oxymatrine is increased greatly. This is mainly due to an obvious improvement of the lipophilic property of oxymatrine-phospholipid complex compared with oxymatrine material and an increase in gastrointestinal absorption.

Administration, Oral ; Alkaloids ; administration & dosage ; chemistry ; pharmacokinetics ; Animals ; Anti-Arrhythmia Agents ; administration & dosage ; chemistry ; pharmacokinetics ; Area Under Curve ; Biological Availability ; Male ; Phospholipids ; chemistry ; Plants, Medicinal ; chemistry ; Quinolizines ; administration & dosage ; chemistry ; pharmacokinetics ; Rats ; Rats, Wistar ; Sophora ; chemistry

OBJECTIVETo observe the effect of total flavonoids from Scutellaria amoena on the experimental arrhythmia.

METHODExperimental animals anesthetized with 10% chloral hydrate were evenly randomized into control group, positive control group, and low-dose, middle-dose and high-dose total flavonoids groups. The experimental arrhythmia ouabain-induced in guinea pigs and barium chloride or calcium chloride-induced in rats were observed and detected respectively. The result was converted into cumulative dosage of ouabain, in guinea pig model. In rat model, the duration of arrhythmia were detected.

RESULThold dosage of ventricular premature heat (VP) and ventricular fibrillation( VF) ouabain-induced in guinea pigs was markedly elevated, and the duration of ventricular tachycardia (VT) barium chloride-induced and VF calcium chloride-induced in rats was postponed by total flavonoids from S. amoena.

CONCLUSIONTotal flavonoids from S. amoena has obvious protective effect on drug-induced arrhythmia.

Animals ; Anti-Arrhythmia Agents ; administration & dosage ; Arrhythmias, Cardiac ; drug therapy ; Disease Models, Animal ; Female ; Flavonoids ; administration & dosage ; Guinea Pigs ; Humans ; Male ; Plant Extracts ; administration & dosage ; Rats ; Rats, Sprague-Dawley ; Scutellaria ; chemistry

OBJECTIVETo observe the therapeutic efficacy and safety of amiodarone combined with Shenmai Injection (参麦注射液) on atrial fibrillation.

METHODSA total of 351 patients with atrial fibrillation caused by cardiovascular diseases and idiopathic atrial fibrillation were assigned to amiodarone group (control group, 128 cases) and amiodarone combined with Shenmai Injection group (treatment group, 223 cases). The patients in the control group received intravenous injection of 150 mg amiodarone in 10 min, followed by intravenous drip infusion at 1 mg /min and 6 h later at 0.5 mg /min until 48 h or cardioversion. The patients in the treatment group received the same treatment of amiodarone, while in addition, they received an injection of Shenmai Injection of 100 mL simultaneously. Blood pressure, ventricular rate, and cardioversion were observed.

RESULTSThe total efficiency rate was 98% (control group) and 99% (treatment group) (P>0.05). The mean ventricular rate decreased 23% and 31% in the control group and the treatment group, respectively (P<0.05). The mean cardioversion time of the two groups was 570±211 min and 351±123 min, respectively (P<0.05). Only mild side effects were observed in both groups.

CONCLUSIONCompared with amiodarone, amiodarone combined with Shenmai Injection takes effect more quickly with low side effects on the treatment of atrial fibrillation.

Aged ; Aged, 80 and over ; Amiodarone ; administration & dosage ; adverse effects ; therapeutic use ; Anti-Arrhythmia Agents ; administration & dosage ; adverse effects ; therapeutic use ; Atrial Fibrillation ; drug therapy ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; adverse effects ; therapeutic use ; Female ; Humans ; Male ; Middle Aged

BACKGROUNDAtrial fibrillation (AF) is one of the most common arrhythmia after coronary artery bypass grafting (CABG), which not only increases the suffering of the patients, but also prolongs hospital stay and enhances cost of care, especially for patients older than 70 years. This study was designed to evaluate the efficacy and safety of low-dose amiodarone in the prevention of AF after CABG, especially for the elderly.

METHODSTwo hundred and ten senile patients undergoing off-pump CABG were included in this prospective, randomized, double-blind and placebo controlled study. Patients were given 10 mg/kg of amiodarone (low-dose amiodarone group, n = 100) or placebo (control group, n = 110) daily for 7 days before surgery and followed by 200 mg of amiodarone or placebo daily for 10 days postoperatively.

RESULTSPostoperative AF occurred in 16 patients (16%) receiving amiodarone and in 36 (37.7%) patients receiving placebo (P = 0.006). AF occurred at (58.13 +/- 16.63) hours after CABG in the low-dose amiodarone group and at (45.03 +/- 17.40) hours in the control group (P = 0.018). The maximum ventricular rate during AF was significantly slower in the low-dose amiodarone group ((121.42 +/- 28.91) beats/min) than in the control group ((134.11 +/- 30.57) beats/min, P = 0.036). The duration of AF was (10.92 +/- 9.56) hours for the low-dose amiodarone group compared with (14.81 +/- 10.37) hours for the control group (P = 0.002). The postoperative left ventricular ejection fraction (LVEF) was significantly improved in the low-dose amiodarone group (from (59.9 +/- 10.3)% to (63.4 +/- 11.4)%, P = 0.001), and significantly higher compared with the control group ((58.5 +/- 10.7)%, P = 0.002). Both groups had a similar incidence of complication other than rhythm disturbances (12.0% vs 16.4%, P = 0.368). The low-dose amiodarone group patients had shorter hospital stays ((11.8 +/- 3.2) days vs (13.8 +/- 4.7) days, P = 0.001) and lower cost of care (RMB (79 115 +/- 16 673) Yuan vs RMB (84 997 +/- 21 587) Yuan, P = 0.031) than that of control group patients. The in-hospital mortality was not significantly different between the two groups (1.0% vs 0.9%, P = 0.946).

CONCLUSIONSPerioperative low-dose oral amiodarone appeared to be cost-effective in the prevention and delay of new-onset postoperative AF in aged patients. It significantly reduced ventricular rate and duration of AF after CABG, decreased hospital cost and stay, as well as promoted the amelioration of left ventricular systolic function. Furthermore, low-dose amiodarone was safe to use and well tolerated with low toxic and side effects, and did not increase the risk of complications and mortality. It is proved to be a first-line therapy and as routine prophylaxis for AF after CABG, especially for elderly patients complicated with left ventricular dysfunction.

Aged ; Amiodarone ; administration & dosage ; Anti-Arrhythmia Agents ; administration & dosage ; Atrial Fibrillation ; etiology ; prevention & control ; Coronary Artery Bypass ; adverse effects ; Double-Blind Method ; Drug Administration Schedule ; Female ; Humans ; Male ; Treatment Outcome

BACKGROUND/AIMS: Most current knowledge regarding amiodarone toxicity derives from clinical trials. This study was performed to investigate the incidence and risk factors of overall adverse effects of amiodarone in real-world practice using a large sample size. METHODS: Between January 1, 2000 and March 10, 2012, a total of 930 consecutive patients who had been treated with amiodarone for arrhythmia were reviewed retrospectively. An amiodarone-associated adverse event was considered in cases of discontinuation or drug dose reduction due to an unexpected clinical response. RESULTS: The mean daily dose of amiodarone was 227 +/- 126 mg, and the mean duration was 490 +/- 812 days. During the mean follow-up duration of 982 +/- 1,137 days, a total of 154 patients (16.6%) experienced adverse effects related to amiodarone, the most common being bradycardia or conduction disturbance (9.5%). Major organ toxicities in the thyroid (2.5%), liver (2.2%), eyes (0.6%), and lungs (0.3%) were rare. All patients recovered fully without complications after amiodarone discontinuation or dose reduction. The only independent predictor of adverse effects was the duration of amiodarone treatment (odds ratio, 1.21; 95% confidence interval, 1.03 to 1.41; p = 0.016, per year). CONCLUSIONS: Low-dose amiodarone is well tolerated in a real-world clinical population. Further studies with a prospective design are needed to confirm this finding.
Aged ; Amiodarone/administration & dosage/*adverse effects ; Anti-Arrhythmia Agents/administration & dosage/*adverse effects ; Arrhythmias, Cardiac/drug therapy ; Atrioventricular Block/chemically induced/epidemiology ; Bradycardia/chemically induced/epidemiology ; Female ; Humans ; Incidence ; Male ; Middle Aged ; Republic of Korea ; Retrospective Studies ; Risk Factors

Thyrotoxic periodic paralysis (TPP) is a rare manifestation of hyperthyroidism characterized by muscle weakness and hypokalemia. All ethnicities can be affected, but TPP typically presents in men of Asian descent. The most common cause of TPP in thyrotoxicosis is Graves' disease. However, TPP can occur with any form of thyrotoxicosis. Up to our knowledge, very few cases ever reported the relationship between TPP and painless thyroiditis. We herein report a 25-yr-old Korean man who suffered from flaccid paralysis of the lower extremities and numbness of hands. The patient was subsequently diagnosed as having TPP associated with transient thyrotoxicosis due to painless thyroiditis. The paralytic attack did not recur after improving the thyroid function. Therefore, it is necessary that early diagnosis of TPP due to transient thyrotoxicosis is made to administer definite treatment and prevent recurrent paralysis.
Administration, Oral ; Adult ; Anti-Arrhythmia Agents/therapeutic use ; Humans ; Hypokalemic Periodic Paralysis/*diagnosis/drug therapy/etiology ; Male ; Organotechnetium Compounds/chemistry/diagnostic use ; Potassium Chloride/therapeutic use ; Propranolol/therapeutic use ; Radiopharmaceuticals/diagnostic use ; Thyroiditis/*complications/radiography/ultrasonography ; Thyrotoxicosis/*diagnosis/etiology

The purpose of the present study was to examine the effects of oxidative stress on ventricular arrhythmias in rabbits with adriamycin-induced cardiomyopathy and the relationship between oxidative stress and ventricular arrhythmia. Forty Japanese white rabbits were randomly divided into four groups (n=10 in each): control group, metoprolol (a selective β1 receptor blocker) group, carvedilol (a nonselective β blocker/α-1 blocker) group and adriamycin group. Models of adriamycin-induced cardiomyopathy were established by intravenously injecting adriamycin hydrochloride (1 mg/kg) to rabbits via the auri-edge vein twice a week for 8 weeks in the adriamycin, metoprolol and carvedilol groups. Rabbits in the control group were given equal volume of saline through the auri-edge vein. Rabbits in the metoprolol and carvedilol groups were then intragastrically administrated metoprolol (5 mg/kg/d) and carvedilol (5 mg/kg/d) respectively for 2 months, while those in the adriamycin and control groups were treated with equal volume of saline in the same manner as in the metroprolol and carvedilol groups. Left ventricular end diastolic diameter (LVEDd) and left ventricular ejection fraction (LVEF) were measured by echocardiography. Plasma levels of N-terminal pro B-type natriuretic peptide (NT-proBNP), malondialdehyde (MAD) and superoxide dismutase (SOD) were detected. The left ventricular wedge preparations were perfused with Tyrode's solution. The transmural electrocardiogram, transmural action potentials from epicardium (Epi) and endocardium (Endo), transmural repolarization dispersion (TDR) were recorded, and the incidences of triggered activity and ventricular arrhythmias were obtained at rapid cycle lengths. The results showed that TDR and the serum MDA and NT-proBNP levels were increased, and LVEF and the serum SOD level decreased in the adriamycin group compared with the control group. The incidences of triggered activity and ventricular arrhythmia were significantly higher in the adriamycin group than those in the control group (P<0.05). In the carvedilol group as compared with the adriamycin group, the serum SOD level and the LVEF were substantially increased; the TDR, and the serum MDA and NT-proBNP levels were significantly decreased; the incidences of triggered activity and ventricular arrhythmia were obviously reduced (P<0.05). There were no significant differences in the levels of MDA and SOD, LVEF, TDR and the incidences of triggered activity and ventricular arrhythmia between the adriamycin group and the metoprolol group. It was concluded that carvedilol may inhibit triggered activity and ventricular arrhythmias in rabbit with adriamycin-induced cardiomyopathy, which is related to the decrease in oxygen free radials.
Animals ; Anti-Arrhythmia Agents ; administration & dosage ; Antibiotics, Antineoplastic ; Carbazoles ; administration & dosage ; Cardiomyopathies ; chemically induced ; physiopathology ; prevention & control ; Doxorubicin ; Heart Rate ; drug effects ; Male ; Metoprolol ; administration & dosage ; Oxidative Stress ; drug effects ; Propanolamines ; administration & dosage ; Rabbits ; Treatment Outcome ; Ventricular Fibrillation ; chemically induced ; physiopathology ; prevention & control