Ventricular arrhythmias can be classified by their frequency and form. This can be used for descriptive and prognostic purposes.
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Frequency Hierarchy
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Class
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nil
|
0
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rare (< 1 VPC per hour)
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I
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infrequent (1-9 VPCs per hour)
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II
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intermediate (10-29 VPC per hour)
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III
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frequent (>= 30 VPCs per hour)
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IV
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where:
• VPC = ventricular premature contraction
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Forms Hierarchy
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Class
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uniform morphology, unifocal
|
A
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multiform, multifocal
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B
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repetitive forms in couplets or salvos (3-5 consecutive ventricular complexes)
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C
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nonsustained ventricular tachycardia ( >= 6 consecutive ventricular complexes, to runs <= 30 seconds)
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D
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sustained ventricular tachycardia ( runs of ventricular complexes > 30 seconds)
|
E
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