- Does magnesium shorten QT interval?
- How can you tell Torsades de Pointes?
- What is Torsades de Pointes?
- What can cause torsades?
- Do you have a pulse with torsades?
- Is polymorphic VT the same as torsades?
- Do you shock pea?
- Is torsades VT or VF?
- Where does torsades de pointes originate?
- Can amiodarone cause torsades?
- Can dehydration cause prolonged QT?
- Which is the most lethal arrhythmia?
- What is the drug of choice for torsades de pointes?
- Why is magnesium used for torsades?
- Do you defibrillate torsades?
- Does a pacemaker prevent torsades?
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).
How can you tell Torsades 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 is Torsades de Pointes?
Torsade de pointes is an uncommon and distinctive form of polymorphic ventricular tachycardia (VT) characterized by a gradual change in the amplitude and twisting of the QRS complexes around the isoelectric line (see the image below).
What can cause torsades?
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.
Do you have a pulse with torsades?
Today one needs to be aware that drug-induced long QT syndrome is common and hence, a thorough medication history must be obtained. Patients with torsade may be hypotensive, have a rapid pulse and have loss of consciousness.
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.
Do you shock pea?
Rhythms that are not amenable to shock include pulseless electrical activity (PEA) and asystole. In these cases, identifying primary causation, performing good CPR, and administering epinephrine are the only tools you have to resuscitate the patient.
Is torsades VT or VF?
Frequent PVCs with ‘R on T’ phenomenon trigger a run of polymorphic VT which subsequently begins to degenerate to VF. QT is difficult to see because of artefact but appears slightly prolonged (QTc ~480ms), making this likely to be TdP.
Where does torsades de pointes originate?
Results: The most common site of origin of TdP was the outflow tract (56%), followed by the inferior left ventricle (32%) and inferior right ventricle (12%).
Can amiodarone cause torsades?
However, a few cases of torsade de pointes have been reported after intravenous amiodarone [1–4]. By definition, drug-induced QTc prolongation normalizes after drug discontinuation, but, in the case of amiodarone, this time the interval is not well defined.
Can dehydration cause prolonged QT?
Electrolyte abnormalities Disturbances in the levels of ions such as sodium and potassium in your body due to conditions such as dehydration, severe diarrhea, and even eating disorders can cause long QT syndrome. The QT interval returns to normal when the ions get back to normal.
Which is the most lethal arrhythmia?
Arrhythmias that occur in the atria (the top chambers of the heart) are supraventricular (above the ventricles) in origin. These arrhythmias are not responsible for dramatic events such as sudden cardiac death, but the most common arrhythmia, atrial fibrillation, is supraventricular and can lead to fatal strokes.
What is the drug of choice for torsades de pointes?
Treatment of torsade de pointes includes: isoproterenol infusion, cardiac pacing, and intravenous atropine. Intravenous magnesium sulfate, a relatively new mode of therapy for torsade de pointes, was proven to be extremely effective and is now regarded as the treatment of choice for this arrhythmia.
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.
Do you defibrillate torsades?
Occasional patients will have recurrent episodes of torsades (“Torsades storm”). Each individual episode may be treated with magnesium or defibrillation, if needed (Treatment step #1 above). However, additional therapies are required to stop recurrence and end the storm.
Does a pacemaker prevent torsades?
The pacemaker component of such devices should in theory help prevent torsades by preventing bradycardia. However, the rate of most pacemakers is not likely to provide protection from torsades.