Using leads I and aVF the axis can be calculated to within one of the four quadrants at a glance.
If the axis is in the "left" quadrant take your second glance at lead II.
- both I and aVF +ve = normal axis
- both I and aVF -ve = axis in the Northwest Territory
- lead I -ve and aVF +ve = right axis deviation
- lead I +ve and aVF -ve
- lead II +ve = normal axis
- lead II -ve = left axis deviation
causes of a Northwest axis (no man's land)
- emphysema
- hyperkalaemia
- lead transposition
- artificial cardiac pacing
- ventricular tachycardia
causes of right axis deviation
- normal finding in children and tall thin adults
- right ventricular hypertrophy
- chronic lung disease even without pulmonary hypertension
- anterolateral myocardial infarction
- left posterior hemiblock
- pulmonary embolus
- Wolff-Parkinson-White syndrome - left sided accessory pathway
- atrial septal defect
- ventricular septal defect
causes of left axis deviation
- left anterior hemiblock
- Q waves of inferior myocardial infarction
- artificial cardiac pacing
- emphysema
- hyperkalaemia
- Wolff-Parkinson-White syndrome - right sided accessory pathway
- tricuspid atresia
- ostium primum ASD
- injection of contrast into left coronary artery
note: left ventricular hypertrophy is not a cause left axis deviation
نظرات شما عزیزان:
ارسال توسط سعيد باباجاني-ارشد مراقبتهاي ويژهMSc
آخرین مطالب