Amiodarone chlorhydrate is a diiodated benzofuran derivative, and it is used to treat cardiac rhythm abnormalities. Hepatotoxicity is a relatively uncommon side effect of amiodarone, and symptomatic hepatic dysfunction occurs in fewer than 1% of the patients taking amiodarone. Cirrhosis is a rare complication that's been confirmed in 12 cases. Peripheral neuropathy occurs in 10% of patients taking aminodarone. We report here on an unusual case of amiodarone-induced hepatotoxicity and peripheral neurotoxicity. A 75 year old man with normal liver function was given amiodarone for treating his atrial fibrillation and heart failure. He developed nausea, vomiting, muscle weakness and wasting after 17.8 months therapy with amiodarone (400 mg orally once per day). Liver biopsy showed the presence of foam cells in the hepatic sinusoids and Mallory bodies in the periportal hepatocytes on light microscopy. Sural nerve biopsy showed demyelination, and nerve conduction studies showed mixed sensorimotor polyneuropathy. These observations show the necessity of monitoring the hepatic function and conducting neurologic examination of the patients treated with amiodarone.
Aged ; Amiodarone/*adverse effects ; Anti-Arrhythmia Agents/*adverse effects ; Hepatitis, Toxic/*etiology ; Humans ; Liver Cirrhosis/chemically induced ; Male ; Polyneuropathies/*chemically induced

Amiodarone ; adverse effects ; Anti-Arrhythmia Agents ; adverse effects ; Arrhythmias, Cardiac ; drug therapy ; Corneal Diseases ; chemically induced ; Humans ; Male ; Middle Aged

OBJECTIVETo investigate the effect and potential mechanism of lysophosphatidic acid (LPA) and antiarrhythmic peptide (AAP10) on rabbit ventricular arrhythmia.

METHODSTwenty-four rabbits were randomly divided into three groups (n = 8 each): control group, LPA group and AAP10 + LPA group. Using arterially perfused rabbit ventricular wedge preparations, transmural ECG and action potentials from both endocardium and epicardium were simultaneously recorded in the whole process of all experiments with two separate floating microeletrodes. The incidence of ventricular arrhythmia post S1S2 stimulation was recorded. Protein levels of nonphosphorylated Cx43 and total Cx43 were evaluated by Western blot. The distribution of nonphosphorylated Cx43 was observed by confocal immunofluorescence microscopy.

RESULTSCompared with the control group, the QT interval, endocardial action potential duration, transmural repolarization dispersion (TDR) and incidence of ventricular arrhythmia were significantly increased and nonphosphorylated Cx43 expression was significantly upregulated in the LPA group. Compared with the LPA group, cotreatment with AAP10 can reduce the QT interval, endocardial action potential duration, TDR and incidence of ventricular arrhythmia (25.0% vs 62.5%, P < 0.01) and downregulate nonphosphorylated Cx43.

CONCLUSIONSLPA could promote the arrhythmia possibly by upregulating nonphosphorylated Cx43 and subsequent gap junction transmission inhibition. Gap junction enhancer AAP10 could attenuate the pro-arrhythmic effect of LPA probably by downregulating myocardial nonphosphorylated Cx43 expression.

Animals ; Anti-Arrhythmia Agents ; pharmacology ; Arrhythmias, Cardiac ; chemically induced ; metabolism ; physiopathology ; Connexin 43 ; metabolism ; Lysophospholipids ; adverse effects ; Oligopeptides ; pharmacology ; Rabbits

For evaluating the effects of thoracic epidural anesthesia, with or without bilateral vagotomy, epinephrine-induced arrhythmias were studied in 31 rabbits anesthetized with 1 minimum alveolar concentration of enflurane. We divided the rabbits into 5 groups: Group I (epidural saline as control group; n=6), Group II (epidural lidocaine without vagotomy; n=6), Group III (intravenous lidocaine; n=7), Group IV (epidural saline with vagotomy; n=6), and Group V (epidural lidocaine with vagotomy; n=6). Using logdose protocol, epinephrine was infused at an initial rate of 0.67 microg/kg/min and increased by Exp[0.4] until arrhythmias occurred; if arrhythmias occurred at any of these doses, a smaller dose, divided by Exp[0.2], was tested. Arrhythmic dose of epinephrine was defined as the smallest infusion rate needed to produce four or more arrhythmias within 15 sec during epinephrine infusion. Arrhythmic dose of epinephrine and its plasma concentration in epidural lidocaine group were significantly higher than control (p<0.05). Similarity of results was also noted amongst the intravenous lidocaine group, vagotomy only group, and vagotomized epidural lidocaine group with respect to the control. These results suggest that thoracic epidural anesthesia raises the threshold for enflurane-epinephrine induced arrhythmias in rabbits and that this effect is eliminated by bilateral vagotomy.
Anesthesia, Epidural ; Anesthesia, Local ; Anesthetics, Inhalation ; Animal ; Anti-Arrhythmia Agents/therapeutic use* ; Arrhythmia/drug therapy* ; Arrhythmia/chemically induced ; Enflurane ; Epinephrine ; Female ; Hemodynamics ; Human ; Lidocaine/therapeutic use* ; Male ; Rabbits ; Vagotomy*

Acute amiodarone toxicity after a single dose of intravenous amiodarone is very rarely seen. We report the case of a 64-year-old Chinese man who presented with atrial fibrillation and fluid overload due to congestive cardiac failure. He was treated with a single bolus dose of intravenous amiodarone, after which he developed elevated serum transaminases, coagulopathy, thrombocytopenia and acute renal failure. His parameters returned to normal after 25 days and his recovery was uneventful.
Acute Kidney Injury ; chemically induced ; Amiodarone ; adverse effects ; Anti-Arrhythmia Agents ; adverse effects ; Atrial Fibrillation ; drug therapy ; Blood Coagulation Disorders ; chemically induced ; Heart Failure ; complications ; drug therapy ; Humans ; Male ; Middle Aged ; Thrombocytopenia ; chemically induced ; Transaminases ; blood ; Treatment Outcome

Patients who overdose on aconite can present with life-threatening ventricular arrhythmia. Aconite must be prepared and used with caution to avoid cardiotoxic effects that can be fatal. We herein describe a case of a patient who had an accidental aconite overdose but survived with no lasting effects. The patient had prepared Chinese herbal medication to treat his pain, which resulted in an accidental overdose of aconite with cardiotoxic and neurotoxic effects. The patient had ventricular tachycardia, bidirectional ventricular tachycardia and ventricular fibrillation. Following treatment with anti-arrhythmic medications, defibrillation and cardiopulmonary resuscitation, he made an uneventful recovery, with no further cardiac arrhythmias reported.
Aconitine ; poisoning ; Adult ; Anti-Arrhythmia Agents ; therapeutic use ; Cardiopulmonary Resuscitation ; Cardiotoxicity ; Drug Overdose ; Drugs, Chinese Herbal ; poisoning ; Electric Countershock ; Electrocardiography ; Humans ; Male ; Tachycardia ; chemically induced ; Tachycardia, Ventricular ; chemically induced ; Treatment Outcome ; Ventricular Fibrillation ; chemically induced

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

AIMTo investigate the antiarrhythmic effect of jumi (JM) extraction.

METHODSThe conventional antiarrhythmic methods were used.

RESULTSAdministration of JM extraction reduced the occurrence of ventricular fibrillation induced by chloroform in a dose-dependent manner in mice. Quinidine significantly decreased the number of ventricular premature beats and ventricular tachycardia, shortened the duration of arrhythmia in aconitine-treated rats. But JM extraction had no effect on aconitine-induced arrhythmia. Compared with control, arrhythmia score was lower in ischemia/reperfusion rats which pretreated with 2.0 g/kg of JM extraction.

CONCLUSIONJM extraction has obvious protection effects in chloroform- and ischemia-induced arrhythmia, but has no effect in aconitine-induced arrhythmia.

Animals ; Anti-Arrhythmia Agents ; therapeutic use ; Arrhythmias, Cardiac ; chemically induced ; drug therapy ; Female ; Male ; Mice ; Plant Extracts ; therapeutic use ; Rats ; Rats, Sprague-Dawley

An unusual grayish brown discoloration of the synovium was found during a knee arthroscopy of a 72-year-old man. He also had similar pigmentation affecting the skin on the legs, arms, hands, and face. It was found he had been taking 400 mg of amiodarone hydrochloride daily for last 7 years. Amiodarone is known to cause a slate grey pigmentation of skin and cornea, but we believe this is the first report of amiodarone-induced pigmentation of the synovium. The arthroscopist should be aware of the possibility of drug-related synovial pigmentation and include this in differential diagnosis.
Aged ; Amiodarone/*adverse effects/therapeutic use ; Anti-Arrhythmia Agents/*adverse effects/therapeutic use ; Arrhythmias, Cardiac/complications/drug therapy ; Arthroscopy ; Diagnosis, Differential ; Humans ; Knee Joint/surgery ; Male ; Pigmentation Disorders/*chemically induced/*diagnosis ; Skin/pathology ; Synovial Membrane/*pathology

This study is to investigate the effects of phenytoin sodium, lidocaine (sodium channel blockers), propranolol (beta-adrenergic receptor antagonist), amiodarone (drugs prolonging the action potential duration) and verapamil (calcium channel blockers) on arrhythmia of mice induced by Bufonis Venenum (Chansu) and isolated mouse hearts lethal dose of Chansu. Arrhythmia of mice were induced by Chansu and then electrocardiograms (ECGs) were recorded. The changes of P-R interval, QRS complex, Q-T interval, T wave amplitude, heart rate (HR) were observed. Moreover, arrhythmia rate, survival rate and arrhythmia score were counted. Isolated mouse hearts were prefused, and the lethal dose of Chansu was recorded. Compared with control group, after pretreatment with phenytoin sodium, broadening of QRS complex and HR were inhibited, and the incidence of ventricular arrhythmia was reduced dramatically, while survival rate was improved; the isolated mouse hearts lethal dose of Chansu was increased significantly. After pretreatment with lidocaine, the prolongation of P-R interval and broadening of QRS complex were inhibited, and the incidences of ventricular arrhythmia were reduced dramatically, while survival rate was improved; the isolated mouse hearts lethal dose of Chansu was increased significantly. After pretreatment with propranolol, prolongation of P-R interval, broadening of QRS complex, prolongation of Q-T interval and HR were inhibited, and the incidences of both supraventricular and ventricular arrhythmias were reduced dramatically, while survival rate was improved. After pretreatment with amiodarone, HR was inhibited, the incidences of ventricular tachycardia were reduced dramatically. Lastly, after pretreatment with verapamil, the prolongation of P-R interval and Q-T interval were inhibited and the incidences of both supraventricular and ventricular arrhythmias were reduced dramatically; the isolated mouse hearts lethal dose of Chansu was reduced significantly. In in vivo experiments, phenytoin sodium was most effective against the mice arrhythmias induced by Chansu while cautious use of verapamil for Chansu inducing arrhythmia should be noted. It is also concluded that mice ventricular arrhythmias induced by Chansu might be most closely related to sodium channel, supraventricular arrhythmias might be related to beta-adrenergic receptor, and calcium channel plays an important role in conduction block. In in vitro experiments, phenytoin sodium was most effective, followed by lidocaine and propranolol, and amiodarone had no obvious effect and verapamil reduced the lethal dose of Chansu.
Amiodarone ; pharmacology ; Animals ; Anti-Arrhythmia Agents ; pharmacology ; Arrhythmias, Cardiac ; chemically induced ; physiopathology ; Bufanolides ; toxicity ; Electrocardiography ; drug effects ; Female ; Heart Rate ; drug effects ; In Vitro Techniques ; Lethal Dose 50 ; Lidocaine ; pharmacology ; Male ; Mice ; Phenytoin ; pharmacology ; Propranolol ; pharmacology ; Verapamil ; pharmacology