A 45 year old man comes to emergency with dizziness. He had supraventricular beats. He is on aspirin, atenolol and quinine. EKG Reveals Torsades De Pointes. He should be managed by:
**Core Concept**
The patient's EKG shows Torsades de Pointes, a specific type of abnormal heart rhythm, also known as TdP, characterized by a rapid, irregular heart rate with a risk of degenerating into ventricular fibrillation. TdP is often associated with prolongation of the QT interval on the EKG.
**Why the Correct Answer is Right**
The patient is on quinine, which is known to prolong the QT interval by blocking the rapid component of the delayed rectifier potassium current (IKr) in the heart. This prolongation of the QT interval increases the risk of developing Torsades de Pointes. The management of TdP involves correcting the underlying cause, which in this case is the quinine-induced QT prolongation, and using magnesium sulfate to stabilize the cardiac membrane potential. Magnesium sulfate works by blocking the L-type calcium channels, which helps to shorten the action potential duration and reduce the risk of TdP.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because beta-blockers, such as atenolol, can actually worsen QT prolongation and increase the risk of TdP, especially in the setting of bradycardia.
**Option B:** This option is incorrect because the patient is already on aspirin, which is not typically used to manage TdP.
**Option C:** This option is incorrect because while correcting the underlying cause of the QT prolongation is important, this option does not specifically address the acute management of TdP.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that magnesium sulfate is the first-line treatment for Torsades de Pointes, and it should be administered promptly in cases of suspected TdP.
**Correct Answer: C. Magnesium sulfate should be administered promptly.**