Answer: 100 beats per minute
Polymorphic ventricular tachycardia, popularly known as Torsades de pointes ("twisting of the points.") is defined as a ventricular rhythm faster than 100 beats per minute in adults with frequent variations of the QRS axis, morphology, or both. Although minimum heart rate required is 100 beats per minute, usually heart rate runs between 160 to 250 beats per minute.
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