Humans ; Torsades de Pointes

No abstract available.
Magnesium Sulfate* ; Magnesium* ; Torsades de Pointes*

Although amiodarone is generally regarded as safe with a low incidence of associated arrhythmias, torsade de pointes (TdP) has been observed usually in the presence of predisposing factors. We report a case of amiodarone-induced TdP after long-term administration of a low dose of oral amiodarone in the absence of predisposing factors.
Amiodarone ; Arrhythmias, Cardiac ; Incidence ; Torsades de Pointes

No abstract available.
Humans ; Long QT Syndrome ; Postoperative Period ; Torsades de Pointes

Torsades de pointes (TdP) is a rare complication of a complete atrioventricular block with QT prolongation. Additional risk factors, such as hypokalemia, may increase the risk of TdP during atrioventricular (AV) block. We experienced a case of TdP, caused by a complete heart block and hypokalemia, which was successfully treated by implanting a permanent pacemaker and correction of the electrolyte imbalance.
Atrioventricular Block* ; Heart Block ; Hypokalemia* ; Risk Factors ; Torsades de Pointes*

Diagnosis, Differential ; Electrocardiography ; Humans ; Tachycardia, Ventricular ; Torsades de Pointes

Electrocardiography ; Female ; Humans ; Syncope/etiology* ; Torsades de Pointes/etiology*

Torsades de pointes associated with a prolonged QT interval is a life-threatening arrhythmia, which may be induced by any of the following: drugs, electrolyte imbalances, severe bradycardia and intracranial hemorrhage. Torsades de pointes is characterized by beat-to-beat variations in the QRS complexes in any ECG leads with rates of 200~250 per minute. Fluoroquinolones are widely used and well tolerated antibacterial agents. However, prolongation of the QT interval leads rarely to Torsades de pointes as a significant adverse effect. So, it should be used with caution in high-risk patients for developing Torsades de pointes. We report one case of 67-year old man with contact burns who experienced Torsades de pointes, which probably resulted from the use of levofloxacin, and no further episode occurred after its withdrawal.
Anti-Bacterial Agents ; Arrhythmias, Cardiac ; Bradycardia ; Burns ; Electrocardiography ; Fluoroquinolones ; Humans ; Intracranial Hemorrhages ; Ofloxacin ; Torsades de Pointes

OBJECTIVETo investigate the mechanism of drug-induced torsade de pointes (Tdp) in dogs.

METHODSIn arterially perfused canine left ventricular wedge preparations, the action potential duration (APD) of the endocardial (Endo), midmyocardial (M) and epicardial (Epi) myocytes, and transmural electrocardiogram (ECG) were recorded simultaneously. The effects of different concentrations of D-Sotalol on APD, transmural dispersion of repolarization (TDR), early after depolarization (EAD) and Tdp were observed.

RESULTSD-Sotalol prolonged APD of the Endo, M and Epi cells in a concentration-dependent manner from 0-100 µmol/L, and increased TDR due to a preferential APD prolongation of the M cells relative to Epi and Endo cells. The application of D-Sotalol elicited EAD, R on T ventricular premature beats, transmural reentry and Tdp in the M cells.

CONCLUSIONEAD and R on T ventricular premature beats induced by D-Sotalol in M cells triggers Tdp, which is maintained by TDR increment and transmural reentry.

While some fluoroquinolone antibiotics can cause QT prolongation and Torsades de Pointes (TdP), serious proarrhythmic effects from ofloxacin have not been reported. Here, we report a case of ofloxacin-induced Torsades de Pointes with abnormal ECG changes, mimicking acute myocardial infarction. A 68-year-old man developed syncope following hospital admission for the treatment of pulmonary tuberculosis. TdP and marked QT prolongation (QT=0.44 sec, QTc=0.62 sec) were noted, with no remarkable serum electrolyte abnormality. The QT prolongation was followed by ST segment elevation, mimicking acute myocardial infarction. After discontinuation of ofloxacin, the QT interval shortened to 0.336 sec (QTc=0.481 sec), with no recurrence of TdP, although the QT interval remained mildly elevated during the hospital course. From this case, we propose that care should be taken in the use of ofloxacin, especially in patients susceptible to TdP.
Aged ; Anti-Bacterial Agents ; Electrocardiography* ; Humans ; Myocardial Infarction* ; Ofloxacin ; Recurrence ; Syncope ; Torsades de Pointes* ; Tuberculosis, Pulmonary