- What drugs can cause Torsades de Pointes?
- Why is magnesium used for torsades?
- What drugs increase QT interval?
- Why does hypokalemia cause long QT?
- Why do doctors give magnesium?
- Do you defibrillate torsades?
- Does magnesium shorten QT interval?
- Does a pacemaker prevent torsades?
- Is polymorphic VT the same as torsades?
- Is polymorphic v tach the same as torsades?
- What are the symptoms of torsade de pointes?
- What does torsades de pointes look like on ECG?
- What medications should be avoided with long QT syndrome?
- What causes Torsades de Pointes?
- How can torsades de pointes be prevented?
What drugs can cause Torsades de Pointes?
DRUGS THAT CAUSE QT PROLONGATION AND/OR TORSADES DE POINTESAntiarrhythmics.
Other QT prolonging drugs that have been withdrawn..
Why is magnesium used for torsades?
Magnesium is the drug of choice for suppressing early afterdepolarizations (EADs) and terminating the arrhythmia. Magnesium achieves this by decreasing the influx of calcium, thus lowering the amplitude of EADs. Magnesium can be given at 1-2 g IV initially in 30-60 seconds, which then can be repeated in 5-15 minutes.
What drugs increase QT interval?
Table 2 Some drugs associated with QTc prolongationAntibiotics. azithromycin. clarithromycin. erythromycin. roxithromycin. metronidazole. (with alcohol) moxifloxan.Antifungals. fluconazole. (in cirrhosis) ketoconazole.Antivirals. nelfinavir.Antimalarials. chloroquine. mefloquine.
Why does hypokalemia cause long QT?
Hypokalemia is another common risk factor in drug-induced LQTS. Low extracellular potassium paradoxically reduces IKr by enhanced inactivation  or exaggerated competitive block by sodium . As a result, hypokalemia prolongs the QT interval.
Why do doctors give magnesium?
Magnesium, given in the hospital by IV, is the treatment of choice to prevent or treat seizures associated with eclampsia or to prevent complications from preeclampsia. Some physicians also use magnesium sulfate to manage pre-term labor.
Do you defibrillate torsades?
Torsades de pointes is a ventricular tachycardia. In the unstable patient, cardiovert. In the pulseless, defibrillate. (The polymorphic nature of the rhythm may interfere with the defibrillator’s ability to synchronize, so cardioversion may not be possible.
Does magnesium shorten QT interval?
Magnesium sulfate reduced the risk of an ibutilide- induced QTc interval increase of greater than 30 msec or greater than 60 msec and reduced the risk of a QTc interval value of more than 500 msec by 65%, 60%, and 68%, respectively (p=0.07, p=0.175, and p=0.160).
Does a pacemaker prevent torsades?
While implantable cardiac devices are given to patients with long QT syndrome and other arrhythmias, there is no data on their use to prevent medication-induced torsades. The pacemaker component of such devices should in theory help prevent torsades by preventing bradycardia.
Is polymorphic VT the same as torsades?
Polymorphic VT is defined as an unstable rhythm with a continuously varying QRS complex morphology in any recorded ECG lead. Polymorphic VT that occurs in the setting of QT prolongation is considered as a distinct arrhythmia, known as torsades de pointes.
Is polymorphic v tach the same as torsades?
Torsades de pointes (TdP) is a specific form of polymorphic ventricular tachycardia occurring in the context of QT prolongation; it has a characteristic morphology in which the QRS complexes “twist” around the isoelectric line.
What are the symptoms of torsade de pointes?
Symptoms of torsades de pointes include:heart palpitations.dizziness.nausea.cold sweats.chest pain.shortness of breath.rapid pulse.low blood pressure.
What does torsades de pointes look like on ECG?
Torsades de pointes is a specific form of polymorphic ventricular tachycardia in patients with a long QT interval. It is characterized by rapid, irregular QRS complexes, which appear to be twisting around the electrocardiogram (ECG) baseline.
What medications should be avoided with long QT syndrome?
Table 1Drugs to be avoided in patients with c-long QT syndromeAnti-depressantMirtazapine, Citalopram, Venlafaxine, Paroxetine, Fluoxetine, Sertraline, Trazodone, Escitalopram, Clomipramine, Amitriptyline, Imipramine, Nortriptyline, Desipramine, Doxepin, Trimipramine, Protriptyline48 more rows•Apr 26, 2013
What causes Torsades de Pointes?
Common causes for torsades de pointes include drug-induced QT prolongation and less often diarrhea, low serum magnesium, and low serum potassium or congenital long QT syndrome. It can be seen in malnourished individuals and chronic alcoholics, due to a deficiency in potassium and/or magnesium.
How can torsades de pointes be prevented?
The first step in managing Torsades de Pointes is preventing its onset by targeting modifiable risk factors. This includes discontinuing any QT prolonging drugs and optimizing a patient’s electrolyte profile. Correcting hypokalemia, hypomagnesemia, and hypocalcemia can all help to prevent the onset of torsades.