Welch Allyn Means ECG Physicians Manual for CP Series Electrocardiographs - User Manual - Manual (Page 8)

MEANS Physicians Manual
Welch Allyn
8
2 Contour analysis
2.1 Contour parameters
All parameters that are used in the diagnostic criteria of the contour classification are
measured in the representative P-QRS-T complex. The lead-independent, overall parameters
are presented in Table 1.
Table 1. Lead-independent parameters for the contour classification.
Name Description
Heart rate Ventricular rate (in beats per minute, BPM)
P axis Axis of the P wave (in degrees, from
–180 to 180)
P duration Duration of the P wave (in ms)
PR interval Duration of the PR interval (in ms)
QRS axis Axis of the QRS complex (in degrees, from

180 to 180)
QRS duration Duration of the QRS complex (in ms)
Corrected QT interval QT interval corrected for heart rate according to Bazett’s formula:
QTc = QT *

(HR/60) (in ms)
Hodges’ formula:
QTc = QT + 1.75 × (HR-60)
Note: The CP 50, CP 100 and CP 200, and the CP 150 and
CP 250 devices support either the Bazett or Hodges QTc
calculation on the printout. MEANS always uses the Bazett
calculation in its interpretive output statements.