Kelly, a 32-year-old college professor, was seen at the clinic. The doctor said that she is probably suffering from torsade des pointes. A 12-lead ECG tracing showed that she has a prolonged QT interval. During history taking, the nurse learns that she has a history of family deafness, previously had hypokalemia, and has likely used what medication?

Question

Quizplus · Accepted Answer

The patient likely took anti arrhythmics. Torsades des pointes is rarely associated with congenital long-QT syndrome and mostly associated with drug administration and electrolyte imbalances. Several antiarrhythmic, anti-infective, anti-psychotics might trigger TdP by blocking specific potassium channels in the myocyte membrane. Their effect reduces the outward potassium current called Ikr. Inhibition of this major re-polarizing potassium current participates in prolongation of the action potential in the ventricular myocardium and this leads to the clinical finding of QT interval prolongation.

Kelly, a 32-Year-Old College Professor, Was Seen at the Clinic