Beware if

*aVr is positive or

*A bipolar lead has a much lower amplitude than other limb leads

*Sinus rhythm between 60-100 bpm

*QRS axis between -30 to +90

*T axis similar to QRS axis

*present

*not too tall ( < 2.5mm in II, <1.5mm in V1)

*not too wide ( < 3mm and less than 1mm between bumps)

*not abnormally inverted (should be upright in inferior leads)

*between 0.12-0.20 seconds

*not too wide (<0.12s)

*not too big (chest leads: maximum R <25mm, maximum S <27mm, maximum R+S <35; limb leads R in aVl <14mm )

*not too small (at least one QRS should exceed 8mm)

*no pathological Qs (Q should be less than 0.04s wide and less than 25% of the following R)

QTC = 0.35-0.43 (QTC=QT/sqr root of RR) (RR=rate/60)

Rule of thumb: QT should be less than 50% of RR...this is true for rates of 60-95 bpm

*not depressed >0.5mm

*elevation <1mm in limb leads, <2mm chest leads

*gently upsloping

*upright in V3-V6

*can be inverted in V1 if not previously upright

*can be inverted in V2, if V1 is also inverted and if V2 was not previously upright

*T axis in limb leads within 45 of QRS axis

*T amplitude between 1/8 and 2/3 of QRS

*<1/3 of T wave

*same direction as T wave

ECG unchanged