Cct exam 2025 questions & answers
What is a vector in the heart? - ANSWERSThe purpose of electrocardiographic investigation is to
find out something about the heart itself by means of an accurate knowledge of its electric
action. This may be repre- sented by the so-called heart-vector, a directed quantity, indicating in
which direction elec- tricity is propagated by the heart.
Left Axis Deviation (LAD) - ANSWERS30-90 degrees
Right Axis Deviation (RAD) - ANSWERS+90 to +180
normal axis - ANSWERS-30 to +90
Extreme Axis Deviation - ANSWERS-90, 180
normal axis qrs in v1 & v2 - ANSWERSpos / pos (thumbs up / thumbs up)
LAD qrs in v1 & v2 - ANSWERSpos / neg (thumb up / thumb down)
RAD qrs in v1 & AvF - ANSWERSneg / pos (thumb down / thumb up)
North West Axis (extreme) qrs in v1 & avF - ANSWERSneg / neg (thumb down / thumb down)
two parts of left bb - ANSWERSleft anterior fascicle & Left posterior fascicle
,right ventricular hypertrophy signs + right axis deviation = - ANSWERSlikelihood of right axis
deviation
LVH on an ecg - ANSWERSsum of S wave in v1 + v2 and the R wave in v5 or v6 is greater than or
equal to >35mm
if pt has LVH (s wave + R wave = >35mm), and pt has RAD (neg/ pos) + - ANSWERSBiventricular
Hypertrophy
deflection of a impulse toward a lead - ANSWERSpositive
deflection of an impulse moving away from lead - ANSWERSnegative
deflection of an impulse moving 90 deg to a lead - ANSWERSsame pos/neg deflection
(equiphasic)
easy 7 steps to finding axis on ecg - ANSWERS1. find the most equiphasic limb lead
2. look at lead running 90 deg to this
3. impulse mainly +Ve? axis is towards this lead
4. impulse mainly -Ve? axis is away from this lead
5. truly equiphasic? yes- you found cardiac axis
6. slightly more +Ve ; move axis 15 deg towards equiphasic lead
7. Slightly more -Ve? Move axis 15 deg away from equiphasic lead
right ventricular hypertrophy (causes) - ANSWERS-pulmonary hypertension
-mitral stenosis
-pulmonary embolism
,-chronic lung disease
-congenital heart disease
right ventricular hypertrophy (leads) - ANSWERS- right axis deviation
- dominant R wave in V1 (>7mm tall or R/S ratio >1)
- dominant S wave in V5 or V6 (>7mm deep or R/S ratio <1)
-QRS duration <120ms (changes not due to rbbb)
Right Atrial Hypertrophy (causes) - ANSWERS- chronic lung disease
- tricuspid stenosis
-congenital heart disease
- primary pulmonary hypertension
-anything that increase size in cell size
Right Atrial Hypertrophy (leads) - ANSWERS- p wave is >2.5mm in the inferior leads (II,III, avF)
->1.5mm in V1&V2
-Think 3 P's
-Pointed, prominent, pulmonary
Left Atrial Hypertrophy (causes) - ANSWERS- mitral stenosis
- systemic hypertension
- aortic stenosis
- hypertension cardiomyopathy
Left Atrial Hypertrophy (leads) - ANSWERSLead 2 P wave
- bifid p wave >40ms between 2 peaks
, - total p wave duration >110 ms
- p mitrale
Lead V1
- Biphasic P wave w terminal negative portion >40ms duration
- Biphasic p wave w terminal negative portion >1 mm deep
left ventricular hypertrophy (causes) - ANSWERS-a thickening of the wall of the heart's main
pumping chamber
Left ventricular hypertrophy ( leads) - ANSWERS-most common used criteria is the sokolov- lyon
- S wave depth in v1 + tallest R wave height in V5- V6 >35mm
enlargement VS hypertrophy - ANSWERSenlargement is increase in chamber size
Hypertrophy is an increase in chamber wall thickness
atrial enlargement - ANSWERSp wave axis is normally +30 deg- +75deg
- if axis shifts right +75deg suggests RAE
- if axis shifts right +30deg, suggests LAE
- look at lead 2 , its a good lead to look at for atrial enlargement
LAE left atrial enlargement - ANSWERS- effects the second part of the pwave
-p wave is 2 parts, right atrial depolarization represents the first half
RAE Right Atrial Enlargement - ANSWERS-effects the first part of p wave
secondary repolarization abnormalities - ANSWERS- consists of downsloping ST seg & T wave
inversion
What is a vector in the heart? - ANSWERSThe purpose of electrocardiographic investigation is to
find out something about the heart itself by means of an accurate knowledge of its electric
action. This may be repre- sented by the so-called heart-vector, a directed quantity, indicating in
which direction elec- tricity is propagated by the heart.
Left Axis Deviation (LAD) - ANSWERS30-90 degrees
Right Axis Deviation (RAD) - ANSWERS+90 to +180
normal axis - ANSWERS-30 to +90
Extreme Axis Deviation - ANSWERS-90, 180
normal axis qrs in v1 & v2 - ANSWERSpos / pos (thumbs up / thumbs up)
LAD qrs in v1 & v2 - ANSWERSpos / neg (thumb up / thumb down)
RAD qrs in v1 & AvF - ANSWERSneg / pos (thumb down / thumb up)
North West Axis (extreme) qrs in v1 & avF - ANSWERSneg / neg (thumb down / thumb down)
two parts of left bb - ANSWERSleft anterior fascicle & Left posterior fascicle
,right ventricular hypertrophy signs + right axis deviation = - ANSWERSlikelihood of right axis
deviation
LVH on an ecg - ANSWERSsum of S wave in v1 + v2 and the R wave in v5 or v6 is greater than or
equal to >35mm
if pt has LVH (s wave + R wave = >35mm), and pt has RAD (neg/ pos) + - ANSWERSBiventricular
Hypertrophy
deflection of a impulse toward a lead - ANSWERSpositive
deflection of an impulse moving away from lead - ANSWERSnegative
deflection of an impulse moving 90 deg to a lead - ANSWERSsame pos/neg deflection
(equiphasic)
easy 7 steps to finding axis on ecg - ANSWERS1. find the most equiphasic limb lead
2. look at lead running 90 deg to this
3. impulse mainly +Ve? axis is towards this lead
4. impulse mainly -Ve? axis is away from this lead
5. truly equiphasic? yes- you found cardiac axis
6. slightly more +Ve ; move axis 15 deg towards equiphasic lead
7. Slightly more -Ve? Move axis 15 deg away from equiphasic lead
right ventricular hypertrophy (causes) - ANSWERS-pulmonary hypertension
-mitral stenosis
-pulmonary embolism
,-chronic lung disease
-congenital heart disease
right ventricular hypertrophy (leads) - ANSWERS- right axis deviation
- dominant R wave in V1 (>7mm tall or R/S ratio >1)
- dominant S wave in V5 or V6 (>7mm deep or R/S ratio <1)
-QRS duration <120ms (changes not due to rbbb)
Right Atrial Hypertrophy (causes) - ANSWERS- chronic lung disease
- tricuspid stenosis
-congenital heart disease
- primary pulmonary hypertension
-anything that increase size in cell size
Right Atrial Hypertrophy (leads) - ANSWERS- p wave is >2.5mm in the inferior leads (II,III, avF)
->1.5mm in V1&V2
-Think 3 P's
-Pointed, prominent, pulmonary
Left Atrial Hypertrophy (causes) - ANSWERS- mitral stenosis
- systemic hypertension
- aortic stenosis
- hypertension cardiomyopathy
Left Atrial Hypertrophy (leads) - ANSWERSLead 2 P wave
- bifid p wave >40ms between 2 peaks
, - total p wave duration >110 ms
- p mitrale
Lead V1
- Biphasic P wave w terminal negative portion >40ms duration
- Biphasic p wave w terminal negative portion >1 mm deep
left ventricular hypertrophy (causes) - ANSWERS-a thickening of the wall of the heart's main
pumping chamber
Left ventricular hypertrophy ( leads) - ANSWERS-most common used criteria is the sokolov- lyon
- S wave depth in v1 + tallest R wave height in V5- V6 >35mm
enlargement VS hypertrophy - ANSWERSenlargement is increase in chamber size
Hypertrophy is an increase in chamber wall thickness
atrial enlargement - ANSWERSp wave axis is normally +30 deg- +75deg
- if axis shifts right +75deg suggests RAE
- if axis shifts right +30deg, suggests LAE
- look at lead 2 , its a good lead to look at for atrial enlargement
LAE left atrial enlargement - ANSWERS- effects the second part of the pwave
-p wave is 2 parts, right atrial depolarization represents the first half
RAE Right Atrial Enlargement - ANSWERS-effects the first part of p wave
secondary repolarization abnormalities - ANSWERS- consists of downsloping ST seg & T wave
inversion
