Summary: 12 leads = 12 views of the heart 10 electrodes used. 4 in limbs, 6 in the chest. Right leg is used as a ground (earth). The electrodes in three limbs form a triangle, which gives 6 views ( 3 Biploar views (Lead I, II, III) and 3 unipolar views (aVR, aVL, and aVF). Other 6 leads (views) are obtained from 6 electrodes placed in the chest region that give Horizontal Plane.
Thanks so much, I am working in a coronary care unit on clinical placement at present and ECGs are going to be the death of me..... this is a great simple explanation. Thanks again
VERY EDUCATIONAL VIDEO, thank you... My only concern is that: in LEAD 2, I see the positive goes from the left foot to the right arm (negative), would I be wrong to say that the camera is looking at the heart from left lower to right upper... basically lead 2 is looking at the heart as you describe lead 3 and vice versa... I just wanna be sure, so correct me if I'm wrong... Thank you again for such an awesome video...
Such a NICE video! I finally got it! Took me ages to read and get this and understand so well. Its teacher's like you that make medicine a beautiful art! Much love from Canada!
This video is nothing short of a masterpiece. To explain a difficult concept so easily truly shows how much of an expert you are. Thank you, Dr. Campbell.
You did what multiple professors and hundreds of other videos on here couldn’t do. This was all I was missing to understand the bigger picture. Thank you 🙏🏻
Wow. I have struggled with this concept for two weeks and you explained it in 10 minutes where I perfectly understood it. Thank you so much for posting this video
Thank you very much for this, doctor! I wish my trainers were anything like as clear and succinct when explaining these concepts. I'm extremely grateful to you for producing such high quality content.
I am sorry, but you are saying here that lead I looks at the heart from the top, lead II from the rx side, and lead III from the lft side. To my knowledge this is incorrect. Lead I looks at the heart from the lateral left side of the heart, lead II looks at the heart from the inferior left side, in fact it is parallel to the wave of depolarisation, this is why we use lead II as standard reference when reading an ECG. Finally, lead III looks at the heart from inferior/right side. Correct me if I am wrong, please...
+Ilaria Giudiceandrea I am an American, and a Paramedic, predisposing me twice to thinking that I know more than I do. BUT, the convention in the US is that what he is describing as Lead I (1) is AVF, and that your interpretation of what Lead I shows, is correct. Older monitors (lifepak 10 and 11) did not have any function with which to "cleverly" do ANYTHING. They showed I, II, and III...all as single, unidirectional, and unfiltered electrical waves. You had to get creative to look at precordial leads (Google MCL 1, MCL 2, etc.). I am not sure why this video explains it differently, I hesitate to say that it's wrong...
Ilaria is absolutely right. What the maker of the video says just about works for the unipolar leads but he has not understood Einthoven's triangle and therefore is incorrect regarding the dipolar leads I, II and III. For the sake of argument, redraw the picture with the right arm and left arm at the patient's side (as it would be when you actually record an ECG - we try not to crucify patients having an ECG taken). Suddenly the line is not above the heart, the triangle is ruined and by the logic of the video should show the inferior of the heart. Does it now show the inferior side of the heart? No. Did it show the superior side of the heart the way drawn here? No. The important thing is the "axis" of the lead; think what direction it is going in, not where a physical line between the electrodes is. The ECG machine records the depolarisation relative to the axis of the different leads allowing multiple views of the heart. Each lead does, of course, not just show a particular part of the heart; you can for instance see evidence of atrial depolarisation, ventricular depolarisation and repolarisation in the same lead. But some leads are better than others at looking at particular parts of the heart, particularly when looking for abnormality. Leads I, II and VL are good for looking at the lateral heart (Lead I is NOT for checking the top and Lead II is NOT medial!). Leads III and VF are best for looking at the inferior side. Lead VR looks at the supero-medial side (ie right atrium). The 6 chest leads give an anterior picture from V1 medially to V6 laterally. How does this all work in practice? You see ST elevation in Leads III and VF and consider inferior MI. You see ST elevation in leads I and VL and consider lateral MI. I am sorry for the lengthy post but I am afraid you will have to look elsewhere to understand Einthoven's triangle. It is unfortunately complicated but you will be OK if you simply learn Lead I (lateral), Lead II (lateral but inferior to I) and Lead III (inferior).
It's Einthoven ( Willem Einthoven) the Nobel Price winner for ECG, not Eindhoven. The later is a city In the province of North Brabant in the Netherlands.
Thank you! I'm in Paramedic school and we just started cardiology, our textbook only gives this about 2 paragraphs of explanation before jumping into rhythms. This video helped me to understand how and why the different leads work, rather than "here's how to put the electrodes on, now just look at Lead II mostly".
Thank you for this. I haven't done the ACLS cause I worked for 5 years in the NICU and ECG skills were barely utilized in our department, if at all. But now I'm trying to transition to adult nursing so I really need to review these topics. This was really helpful, thanks.
I really appreciated this video. Dr. Campbell explained my questions thoroughly, about why it’s called a 12 lead ecg, when you actually only place 10 leads on the patient. I LOVE learning about the heart, and this video did not disappoint! Thank you, Dr. Campbell.
in other videos, they have the view from lead 1 as a lateral line looking from the left arm electrode to the right arm electrode, as opposed to this video having the view of lead 1 being straight down from above the heart. any clarification?
Honestly, I am a Nurse and Physical Therapist by professions. Passed my board exams both in my country and the US; but is only now that 12 lead ekg is clear to me. thank you sir! nice
Great explanation. Just a little confused. To get Eindhoven's Triangle right, should we have the patient's arms widespread while performing the ECG as shown in the video or not? The common practice in hospitals is that they don't spread the patient's arms. Does that make any difference to the accuracy of ECG?
Lead II is the difference in the voltage between the left leg (LL) and right arm electrodes and is directed towards the LL at +60 degrees. It is an inferior lead, that in a healthy heart with normal cardiac axis looks almost directly at the oncoming wave of depolarisation. Hence why cardiac monitors default to lead II as it will normally provide the best view of the p wave and in the limb leads will normally show the largest positive deflection. Lead I is the difference in the voltage between the left arm and right arm electrodes which is directed towards the left at zero degrees. It provides a left lateral view of the patient's heart. Lead III is the difference in voltage between the left leg and left arm electrodes which is directed towards the left leg at +120 degrees. It also provides an inferior view.
Simply spectactular explanation there Dr, you are wonderful. I have been trying to understand this concept all day till bumped into your vid. Thank you ever so much, from the bottom of my heart. no pun intended.
Impressive video! You made it simple in a way that we can easily understand and yet its straightforward! I’ve been looking for this kind of video and this is so helpful. Thanks!
I have watched a number of your videos to help me understand what they don't seem to be able to teach in class, you are amazing! I always understand what your saying and you make everything clear, thank you!
Dr. Campble, you are the best. I am an auditory learner first and foremost and a visual learner second, you present both beautifully, I thank you emensly, thank you, thank you.
Fantastic Video! Video summary 10 electrodes are used 12 leads/ format Eidnoven Triangle Lead I,II,III are first Lead I= view from the top RA and LA Lead II= view from the right arm to left leg Lead III= view from left arm and left leg avr= right side view of heart avl= left side view of the heart avf= view from the foot foot= left leg the right leg is used as the ground earrth There is 6 chest lead also known as precordial lead v1 on the 4th intercostal space to the right of the sternum v2 on the 4th intercostal space to the left of the sternum v4 on the 5th intercoastal space left midcalvicular line V3 between the middle of v2 and v4 V5 placed at same level of v4 but at the axillary line V6 placed at level of V5 midaxillarly line The purpose of all these leads is to give us view of the heart from different angles which is important to detect possible heart problems
I think that if people stopped using the word "Lead" to denote two different things, this would've made life easier :) 12-lead ECG is acquired using 10 wires. There you have it
This seems incorrect e.g. lead 2 looks at the left ventricle from the left hand side that why the qrs is mainly positive in leed 2 as the depolarising powerful LEFT ventricle voltage goes from endocardium to wall epicardium. So he has drawn lead two incorrectly as it looks from the left NOT the right. As a consequence all the Rest of the heart limb leeds views are ALL Wrong
Lead 1 from Top view of heart( Right and Left) Lead 2 : 2nd view from right and inferior Lead 3: 3rd view of heart from Left and inferior aVR augmented Voltage Right aVL augmented Voltage Left aVF augmented Voltage Foot
Brilliant. This should be on the curriculum of any one taking the role of lead placement and what they do and the areas of the heart they read. Certainly helps me understand a bit more.
Summary:
12 leads = 12 views of the heart
10 electrodes used. 4 in limbs, 6 in the chest.
Right leg is used as a ground (earth). The electrodes in three limbs form a triangle, which gives 6 views ( 3 Biploar views (Lead I, II, III) and 3 unipolar views (aVR, aVL, and aVF). Other 6 leads (views) are obtained from 6 electrodes placed in the chest region that give Horizontal Plane.
Thank you so much! This is what I really needed
Thakyou
Thank you!!
Thank you
Thanks 🙂
This seriously explained it SO well!! Thank you so much, have both of your books and really appreciate the way you teach.
I am a nurse and we just had to do this a day ago! This really helped me understand what I was doing. Thanks you!
Such a fantastic teacher, explains cardiology simply but in such an understandable way,thank you so much
Thanks so much, I am working in a coronary care unit on clinical placement at present and ECGs are going to be the death of me..... this is a great simple explanation. Thanks again
OMG you are such a great teacher..
Lot of respect from Pakistan
Amazing explaination thank you Dr. Campbell
Out of All the videos I watched I finnally got it thank you so muchhh
So well explained! Thank you sooooo much Sir👏🏽
thank u very much now I completely understand the concept of 12lead Ecg
The English always make things nice and clear. Cheers.
thanks doc,nice lecture..
Thanks Dr. John
Thanks .That was very helpful
VERY EDUCATIONAL VIDEO, thank you...
My only concern is that: in LEAD 2, I see the positive goes from the left foot to the right arm (negative), would I be wrong to say that the camera is looking at the heart from left lower to right upper... basically lead 2 is looking at the heart as you describe lead 3 and vice versa... I just wanna be sure, so correct me if I'm wrong... Thank you again for such an awesome video...
Yeah this has me stumped as well... From what I have seen so far leads 2 and 3 are wrong in this video. I am learning so I may be incorrect.
Thanks!! it was very helpful.
thank u sir,
Such a NICE video! I finally got it! Took me ages to read and get this and understand so well. Its teacher's like you that make medicine a beautiful art! Much love from Canada!
ها ليج
@@madmedic7174 could you please let me know what is wrong? I don't know anything about ECG. I am learning this just for interest.
عراقي بعد@@user-qr2bf1tj7i 😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂😂
This video is nothing short of a masterpiece. To explain a difficult concept so easily truly shows how much of an expert you are. Thank you, Dr. Campbell.
Oh my goodness! Why didn't any of my teachers explain it this well? Thank you so much for making this available!
I said the same thing
Seems like the old teachings are still the best
Because they don’t know themselves!
@@Liza5888 probably
Seconded!!
took me 7 months to fight with the concept , but now I realized 10:04 minutes were enough ..
The best explanation of 12 lead ECG I've ever seen. Thank you very much, Dr. Campbell!
You did what multiple professors and hundreds of other videos on here couldn’t do. This was all I was missing to understand the bigger picture. Thank you 🙏🏻
I just love you, sir. May Allah give you a healthy and happy life
Wow. I have struggled with this concept for two weeks and you explained it in 10 minutes where I perfectly understood it. Thank you so much for posting this video
Thank you very much for this, doctor! I wish my trainers were anything like as clear and succinct when explaining these concepts. I'm extremely grateful to you for producing such high quality content.
Dear Dr. Campbell, thank you for the amazing lecture ! You make the subject easier to understand, you are magnificent teacher !
This was wonderful. I have been a RN for several years and have struggled with this concept. Thank you!
I never knew...
I could understand it so well...
Without opening my book 📖. 😂😂😂
exactly!
I am sorry, but you are saying here that lead I looks at the heart from the top, lead II from the rx side, and lead III from the lft side. To my knowledge this is incorrect. Lead I looks at the heart from the lateral left side of the heart, lead II looks at the heart from the inferior left side, in fact it is parallel to the wave of depolarisation, this is why we use lead II as standard reference when reading an ECG. Finally, lead III looks at the heart from inferior/right side. Correct me if I am wrong, please...
+Ilaria Giudiceandrea I am an American, and a Paramedic, predisposing me twice to thinking that I know more than I do. BUT, the convention in the US is that what he is describing as Lead I (1) is AVF, and that your interpretation of what Lead I shows, is correct. Older monitors (lifepak 10 and 11) did not have any function with which to "cleverly" do ANYTHING. They showed I, II, and III...all as single, unidirectional, and unfiltered electrical waves. You had to get creative to look at precordial leads (Google MCL 1, MCL 2, etc.). I am not sure why this video explains it differently, I hesitate to say that it's wrong...
+Ilaria Giudiceandrea An assistant professor and cardiologist at my school agrees with what you're saying.
Ilaria is absolutely right. What the maker of the video says just about works for the unipolar leads but he has not understood Einthoven's triangle and therefore is incorrect regarding the dipolar leads I, II and III. For the sake of argument, redraw the picture with the right arm and left arm at the patient's side (as it would be when you actually record an ECG - we try not to crucify patients having an ECG taken). Suddenly the line is not above the heart, the triangle is ruined and by the logic of the video should show the inferior of the heart. Does it now show the inferior side of the heart? No. Did it show the superior side of the heart the way drawn here? No. The important thing is the "axis" of the lead; think what direction it is going in, not where a physical line between the electrodes is. The ECG machine records the depolarisation relative to the axis of the different leads allowing multiple views of the heart. Each lead does, of course, not just show a particular part of the heart; you can for instance see evidence of atrial depolarisation, ventricular depolarisation and repolarisation in the same lead. But some leads are better than others at looking at particular parts of the heart, particularly when looking for abnormality. Leads I, II and VL are good for looking at the lateral heart (Lead I is NOT for checking the top and Lead II is NOT medial!). Leads III and VF are best for looking at the inferior side. Lead VR looks at the supero-medial side (ie right atrium). The 6 chest leads give an anterior picture from V1 medially to V6 laterally. How does this all work in practice? You see ST elevation in Leads III and VF and consider inferior MI. You see ST elevation in leads I and VL and consider lateral MI. I am sorry for the lengthy post but I am afraid you will have to look elsewhere to understand Einthoven's triangle. It is unfortunately complicated but you will be OK if you simply learn Lead I (lateral), Lead II (lateral but inferior to I) and Lead III (inferior).
do you have a video that lcearly explains the triangle having difficulty understanding the 12 lead ecg
Ilaria Giudiceandrea @7:55 I think he is explaining your doubt or is it different?
This is the best explanation of the ECG leads...thank you so much doctor!
It's Einthoven ( Willem Einthoven) the Nobel Price winner for ECG, not Eindhoven. The later is a city In the province of North Brabant in the Netherlands.
hang on, Lead I is dipolar and moves from left to right, so its view will be of the lateral left ventricle. he shows it looking down from the top.
I had an aha! Moment watching this! I'm sharing this with my nursing cohort!
Please reach more topics
U R SUCH GOOD ST TEACHING some more medicine teaching from u.
Thank you! I'm in Paramedic school and we just started cardiology, our textbook only gives this about 2 paragraphs of explanation before jumping into rhythms. This video helped me to understand how and why the different leads work, rather than "here's how to put the electrodes on, now just look at Lead II mostly".
Thanks for this information, I now know to look at lead II mostly
The clearest, easiest to understand explanation of this subject out of the many I've watched, thank you.
Thank you for this. I haven't done the ACLS cause I worked for 5 years in the NICU and ECG skills were barely utilized in our department, if at all. But now I'm trying to transition to adult nursing so I really need to review these topics. This was really helpful, thanks.
This is the simplest explanation I’ve ever received!! I can now say I finally understand this . Thank you so much
Anyone else thought understanding ECG’s was impossible before watching this?
Best explanation ever, thank you so much!!!!
Awesome!!! You nailed it to the point!!! I was not understanding this in the class room. “Let’s move on” yike!!! Thank you again 🤝
Greatest explanation on ECG on RUclips - Thank you very much, Sir!
From this video I think I finally understand ECG's! Thank you! from Bristol, England.
Wow finally I have understood the concept of ecg.
Thank you so much Sir, May God Bless you.
I still can't imagine the view of the heart but at least I've gained a little bit of understanding here. Thanks Dr John Campbell
This is complex simplified💯💯. God bless you doc.
Happy new year dr Campbell you have very clearly explained the position of ECG LEADS THANKS 01/01/2020
I really appreciated this video. Dr. Campbell explained my questions thoroughly, about why it’s called a 12 lead ecg, when you actually only place 10 leads on the patient. I LOVE learning about the heart, and this video did not disappoint! Thank you, Dr. Campbell.
Thank you Sir.
in other videos, they have the view from lead 1 as a lateral line looking from the left arm electrode to the right arm electrode, as opposed to this video having the view of lead 1 being straight down from above the heart. any clarification?
Yeah you are right. Lead one should look from left arm to right arm
Honestly, I am a Nurse and Physical Therapist by professions. Passed my board exams both in my country and the US; but is only now that 12 lead ekg is clear to me. thank you sir! nice
Thank you Dr. Campbell. You speak and explain so clearly. Iam glad I found your video. it's helping me understand things a lot better.
Elizabeth Fine yeah....very clear.
awesome teaching. all of your videos has given such clear and easy information to understand .thank you and God bless you.
Really you are doing wounderful great job May God bless u more and more ❤❤❤💕👌
Great explanation.
Just a little confused.
To get Eindhoven's Triangle right, should we have the patient's arms widespread while performing the ECG as shown in the video or not?
The common practice in hospitals is that they don't spread the patient's arms.
Does that make any difference to the accuracy of ECG?
Cudos Doc, you're eloquent and clear...
Sir, I thank you very much.you are a very good teacher.you made this difficult topic very easy under 10 minutes.
Thank you, from Kenya I say Asante Sana.
I'm confused?? Should lead III be on the right inferior side and lead II be left inferior side??
No. Lead II looks at the right side
Lead II looks from the right, lead III from the left. On these diagrams, we are always looking at someone else.
Lead II is the difference in the voltage between the left leg (LL) and right arm electrodes and is directed towards the LL at +60 degrees. It is an inferior lead, that in a healthy heart with normal cardiac axis looks almost directly at the oncoming wave of depolarisation. Hence why cardiac monitors default to lead II as it will normally provide the best view of the p wave and in the limb leads will normally show the largest positive deflection.
Lead I is the difference in the voltage between the left arm and right arm electrodes which is directed towards the left at zero degrees. It provides a left lateral view of the patient's heart.
Lead III is the difference in voltage between the left leg and left arm electrodes which is directed towards the left leg at +120 degrees. It also provides an inferior view.
Cody Agans rook, it's the pts left not your right
this was explained brilliantly. i'm also getting asmr from your pen so thanks for that too.
Awesome
One of the best explained EKG leads video I ever seen! Thanks! Gracias!
Well done u made it easy
Thnx
You did not mention what leads detect the posterior infarct
Allah bless upon you sir
God bless you also Afzal.
Ameen
Excellent Sir....We would be very thankful to you if you can explain us about Intra Aortic ballon pump....May you be rewarded with the Good......
Thank you!!! You’re Amazing at explaining this stuff
Best video on ecg. Seen many none comes close to this
its Einthoven's triangle, not Eindhoven's at 0:59
Simply spectactular explanation there Dr, you are wonderful. I have been trying to understand this concept all day till bumped into your vid. Thank you ever so much, from the bottom of my heart. no pun intended.
again thanku so much sir .....
Thanks a lot for your great explanation you made a big lecture in 10 minutes understanding...!!! I'm really thankful to you sir...!!!
Thank you so much, Dr.John Campbell! This has been confused me for more than 20 years! I was exhausted! This waked me up! You made it crystal clear!
Such an excellent explanation, I really understood your way of teaching. Thank you❤️
Thank you so much . I keep wondering about the deep interpretation of 12 leads.
Awesomely explained Sir !!
Previously i haven't understood while reading it from book, now my concept is crystal clear.
Wow. Took me a whole year in Med school to understand this but thank you so much Dr. Campbell. Just understood it in 10 minutes.
Thank you so much for this amazing explanation
Impressive video! You made it simple in a way that we can easily understand and yet its straightforward! I’ve been looking for this kind of video and this is so helpful. Thanks!
Thank you!!!!!! For making it so simple and clear....tried with lot other videos but couldn't...finaly
Nice video ...simple way👌🏻
Sir I watched many videos,but this video really made me understand how actually an ECG works.thank you for your effort sir
Thank you so much ,I am from Indonesia ,and now understand with this short explain from you,very clearly
So are we ONLY looking at the ST segments in the various views in a 12 lead ECG? No other characteristics in the pQR segment? ?
Sir , your lectures are very helpful.thanks a lot sir.wish you n your family good health n wealth.👍👍👍👍
I have watched a number of your videos to help me understand what they don't seem to be able to teach in class, you are amazing! I always understand what your saying and you make everything clear, thank you!
Your explanation is clear, logically ordered, would love to see some real samples of 12 lead ecg and interpretation. Thanks.
Wonderful video! Thank you. I really struggled with this subject until your video.
Dr. Campble, you are the best. I am an auditory learner first and foremost and a visual learner second, you present both beautifully, I thank you emensly, thank you, thank you.
Out of all the EKG videos I've watched. This is the best explanation and it makes sense. Easy to understand. Thanks!
Fantastic Video!
Video summary
10 electrodes are used 12 leads/ format Eidnoven Triangle
Lead I,II,III are first
Lead I= view from the top RA and LA
Lead II= view from the right arm to left leg
Lead III= view from left arm and left leg
avr= right side view of heart
avl= left side view of the heart
avf= view from the foot
foot= left leg
the right leg is used as the ground earrth
There is 6 chest lead also known as precordial lead
v1 on the 4th intercostal space to the right of the sternum
v2 on the 4th intercostal space to the left of the sternum
v4 on the 5th intercoastal space left midcalvicular line
V3 between the middle of v2 and v4
V5 placed at same level of v4 but at the axillary line
V6 placed at level of V5 midaxillarly line
The purpose of all these leads is to give us view of the heart from different angles which is important to detect possible heart problems
I think that if people stopped using the word "Lead" to denote two different things, this would've made life easier :) 12-lead ECG is acquired using 10 wires. There you have it
Hilarious how bad ACLS instructors are at explaining this compared to Dr. Campbell. Props, sir.
Thanks! finally I understand how EKG works. You’re the BEST!!!!!❤
It wonderful to have good people to educate the learners .thanks allot it's really helped mi to pass my test.
This seems incorrect e.g. lead 2 looks at the left ventricle from the left hand side that why the qrs is mainly positive in leed 2 as the depolarising powerful LEFT ventricle voltage goes from endocardium to wall epicardium. So he has drawn lead two incorrectly as it looks from the left NOT the right.
As a consequence all the Rest of the heart limb leeds views are ALL Wrong
Very nice way of teaching...
Able to understand very well even those who are not the native English speakers..
Thanks a lot..
Great video, except Lead II and Lead III appear to be reversed, compared to the book I'm reading (ECG Interpretation, Abedin & Conner, 2008)
The simplistic language successively expect because brother-in-law extremely rob along a loose command. brash, fearful fearless society
Lead 1 from Top view of heart( Right and Left)
Lead 2 : 2nd view from right and inferior
Lead 3: 3rd view of heart from Left and inferior
aVR augmented Voltage Right
aVL augmented Voltage Left
aVF augmented Voltage Foot
Brilliant. This should be on the curriculum of any one taking the role of lead placement and what they do and the areas of the heart they read. Certainly helps me understand a bit more.