|
Parameter |
Normal values |
|
P wave |
· ≤3 squares wide (≤0.12s) · ≤3 squares high (actually <2.5mm) · Best seen in II (should be upward) V1 (should be upward or biphasic) |
|
PR interval |
· 2-5 squares (0.12 – 0.2s) · Isoelectric |
|
QRS complex |
· <3 squares (<0.12s) |
|
Q wave |
· ≤1 square wide (≤0.04s) · ≤2 squares deep (≤2mm, and ≤25% height of QRS complex) |
|
ST segment |
· <2 squares (<2mm) deviation from isoelectric in V1-2-3 · <1 squares (<1mm) deviation from isoelectric elsewhere |
|
T wave |
· <5 squares high (<5mm) |
|
QT interval |
· Bazett formula: QTc = QT/√(RR) · ≤440 in men, ≤460 in women · > 350ms in both |