Ventricular Tachycardia Polymorphic | Reference Guide.

EKG Features

Rate: Fast (100-300 bpm)
Rhythm: Regular or irregular
P Wave: Absent
PR Interval: Not measurable
QRS: Normal or wide (>0.10 sec), bizarre looking

Polymorphic ventricular tachycardia has changing ECG shapes from beat to beat. See the pages on ventricular tachycardia, monomorphic VT and Torsade de Pointes for related information.
External Source: http://www.nlm.nih.gov/medlineplus/ency/article/000187.htm
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