ECG Flashcards
Where is V1 lead placed?
fourth intercostal space, to the right of sternum.
Where is V2 lead placed?
fourth intercostal space, to the left of sternum.
Where is V3 lead placed?
placed diagonally between V2 and V4.
Where is V4 lead placed?
between rib 5 and 6 in the midclavicular line.
Where is V5 lead placed?
placed on the same level as V4, but in the anterior maxillary line.
Where is V6 lead placed?
placed on the same level as V4 and V5, but in the midaxillary line.
On the cardiac axis what is normal?
-30 to 90 degrees
If cardiac axis is lower than -30 what is this called
Left axis deviation
If cardiac is higher than +90 what is this called
Right axis deviation
What are reasons for cardiac deviation?
Hypertrophy Cardiomegaly Coronory artery disease Tumor Pregnancy
If you are tall what heart deviation would you have?
Right heart deviation
If you are short what heart deviation would you have?
Left heart deviation
Causes of left heart deviation
Short/ Obese
Inferior MI
Left bundle branch block
Causes of right heart deviation
Tall
PE
Right bundle branch block
If there is a positive deflection of Lead 1 and positive deflection of aVF what cardiac axis is this?
Normal
If there is a negative deflection of Lead 1 and positive deflection of aVF what cardiac axis is this?
Right axis deviation
If there is a positive deflection of Lead 1 and negative deflection of aVF what cardiac axis is this?
Most likely left axis deviation
If there is a positive deflection of Lead 1 and negative deflection of aVF and negative deflection of Lead 2 what cardiac axis is this?
Left axis deviation
Draw the cardiac axis diagram
https://litfl.com/wp-content/uploads/2018/08/Haxaxial-ECG-AXIS-Reference-2021.png
What does the P wave represent?
Atrial depolarisation
What does the QRS complex represent?
Ventricular depolarisation
What does the T wave represent?
Ventricular repolarisation
What does PR interval mean?
Time it takes for electric signal to travel from your atria to ventricles
What does QRS interval mean?
Time it takes for Ventricular depolarisation
What does QT interval mean?
Time it takes for Ventricular depolarisation and Ventricular repolarisation
What is QTc
Correct QT interval
How is QTc calculated?
QT/ square root of R-R interval
What are the normal values for PR interval
120-200 ms
What are the normal values for QRS interval
80-120ms
What are the normal values for QT interval
360-440ms
What is the equation for heart rate from an ECG
300/ Number of large squares between R-R
What is sinus arythmia
Normal irregular rhythm of the heart
What happens to ECG during inspiration
R-R interval shortens
What happens to ECG during expiration
R-R interval lengthens
What is the mechanism for the change in ECG during inspiration
Inspire = vagal tone decreases
Vagal tone keeps your heart rate at a low rate
heart rate increases when you breathe in
What is normal in an ECG for athletes?
LVH- left ventricular hypertrophy
Sinus bradycardia
1st heart degree block
Sometimes ST elevation
What is normal in Caribbean and African populations ECG
Inverted T wave in V3
ST elevation
LVH
What is a sign of ventricular hypertrophy
Big QRS complex
