funny how a 1951 video explains this better than a 2013 lecturer

I'm glad this helped. I don't know of any other embryology videos that have the same qualities as this one: concise narration synchronized with clear animation. This heart video wasn't my work: it was made many years ago by Drs. Blandau and Rushmer. My only role was to restore it. Right now I'm working on an animation to show folding of the embryo. It's slow work! Bob Acland

old masters know how to explain anatomy and embryology. Take a bow in front of these masters

It's 2023 and this video from 72 years ago is the best I've found on the subject. Besides, it's not even my native language.

This video deserve an Oscar Award!

Retro animation explained it better than reading it one 100 time.

Beautiful. Surprisingly, this video made in 1951 supersedes any modern 3-D video in visualizing and conceptualizing the embryological development of the heart. A must watch for those struggling to understand this process.

yo 1951 lectures were legit

My professor is still using this in anatomy class in 2019. I have not found a better explanation so far...

2 years gone by and this is still the best video on the internet on heart embryology!

Transcription of the video: Initially, the heart consists of a simple tube. It’s anchored at one end by the differentiating arterial trunks and at the other by extensive venous channels which drain into the atrium. Being fixed at both ends, the cardiac tube grows rapidly in length and the embryonic ventricle is bent into a loop to the right of the midline. As development continues, the ventricular region swings back to the midline, and expands and grows in length to cover the atrium and great veins. Extensive sacculations projecting laterally will ultimately become the right atrium and left atrium. The future left ventricle lies to the left of the interventricular groove, and the embryonic right ventricular or bulbo-conus region communicates with the truncus arteriosus. A four-chambered heart is formed from this convoluted tube by the development of three septa partitioning the atria, the ventricles and the truncus arteriosus. Although these septa develop simultaneously, they will be considered individually. By viewing the heart from the right side, partitioning of the atria and ventricles can be more easily visualised. Externally, a deep groove separates the atrium from the ventricle. Within the heart, the atrioventricular groove appears as a deep invagination which constricts the atrioventricular canal at its waist. The canal becomes divided along its longitudinal axis by two partitions growing from the walls of the two common chambers toward the auricular-ventricular junction. Endocardial cushions extend from opposite sides of the atrio-ventricular aperture and ultimately fuse into a column, dividing the channel between the atrium and ventricle. From the interventricular ridge, a proliferating muscular septum advances across the common ventricle toward the base of the heart. Simultaneously, the interatrial septum rapidly grows toward the endocardial cushions, progressively constricting the foramen between the atrial chambers, the foramen primum. Before the foramen primum becomes obliterated, a new opening appears, high on the interatrial septum. The timely development of this orifice, the foramen secundum, provides uninterrupted shunting of blood from the right atrium directly into the left. Another interatrial septum, the septum secundum, develops from a ridge just to the right of the septum primum, and extends down like a curtain over the interatrial fenestration. The advanced edge of the septum secundum forms the foramen ovale, with the septum primum acting as a unidirectional flutter valve. Thus, blood can flow only from the right atrium to the left. To recapitulate, the common atrioventricular canal is partitioned by the simultaneous proliferation of the endocardial cushions, the muscular interventricular septum, and the interatrial septum. The septum secundum produces the foramen ovale, with the septum primum acting as a membranous valve. An opening persists between the ventricular cavities. Closure of this interventricular foramen awaits the elaboration of a complex spiral septum, which splits the truncus arteriosus and conus region into the aorta and pulmonary artery. The formation of this partition is more clearly seen if the heart is turned by 45 degrees. Originally, the right and left ventricles share a common outflow channel, the truncus arteriosus, which gives rise to the aortic arches. The truncus arteriosus is presented schematically as a transparent cylinder. The bifurcation of the truncus arteriosus, illustrated here, represents two of the aortic arches. The fourth aortic arch forms the aorta and the sixth is the origin of the pulmonary artery. A pair of ridges, which develop at the bifurcation, spiral down the truncus arteriosus. They fuse along the axis of the cylinder to produce a single spiral septum, extending down towards the ventricles. The interventricular foramen is obliterated by masses of endocardial tissue from the ventricular septum by the endocardial cushions and by the spiral aortic septum. The partitioning of the heart into its component chambers and corresponding arteries is now complete. The significance of the spiral aortic pulmonary septum is more readily-appreciated in a frontal view of the heart. Aortic pulmonary septum executes a spiral of 180 degrees and swings into line with the interventricular septum. This process accounts for the manner in which the aortic and pulmonary trunks are entwined in the fully-developed heart. Blood from the left ventricle enters the aorta, which passes to the right, behind the pulmonary artery. Blood from the right ventricle enters the pulmonary artery, which passes in front of the aorta, turning posteriorly on the left side of the mediastinum. Venous blood from the superior vena cava, and the inferior vena cava flows through the right atrium and into the right ventricle. It’s ejected into the pulmonary artery, where a major portion continues through the ductus arteriosus into the descending aorta. Resistance to flow through the collapsed lungs is so great that only a small quantity of blood enters the pulmonary arteries. A correspondingly small amount of blood is returned through the pulmonary veins into the left atrium. Oxygenated blood from the placenta enters the inferior vena cava, but tends to stream across the right atrium through the foramen ovale, and into the left atrium to supplement the scanty pulmonary venous return. This mixture of venous and oxygenated blood enters the left ventricle and is pumped into the aorta, from which the carotid arteries arise to supply the brain. Through the descending aorta, partially-oxygenated blood is distributed to the lower portions of the body. This circulatory pattern persists throughout the remainder of fetal development. Within a very few minutes after delivery into the external world, the supply of oxygenated blood from the placenta is interrupted. If the infant is to survive, respiratory exchange in the lungs must be promptly established. As the lungs become inflated, the resistance to pulmonary blood flow is markedly reduced. Constriction of the ductus arteriosus diverts the entire right ventricular output into the pulmonary circulation. Oxygenated blood returning from the lungs is distributed through the systemic circulation. When the pressure in the left atrium exceeds that in the right atrium, the valvular is pressed over the foramen ovale, and partitioning of the heart is functionally complete.

I am professor of Human Embriology and this video was a wonderful tool to teach the development of the cardiovascular system in my classes! Great

Absolutely sensational video. I'm a cardiologist and I've never seen this explained so eloquently.

The original video has helped me so much... this is an awesome restoration... A big thanks to all involved in making both the videos.. -----A very grateful medical student....

spend hours trying to get it straight. and this video clarified everything in less than 10 minutes. Thx for posting this!!!!!!! greatly appreciated.

I NEVER understood this until now. THANK YOU.

One of the best embryology lectures ever... No one could explain it better. Pure classic 🖤💪🏼

Wow , what today's lecturer can't do , you did it in 1951, so methodical , pls put videos on cardiac embryology in detail with structure and CHD

This video is still the most helpful one I’ve seen to explain this topic

I cannot express how thankful I am about this video. This saved valuable hours of my time that I would have spent on understanding this process. Thank you so much.

89 slides and 3 hours of lectures couldn't teach this well. It's awesome!!!!

Dr. Robert Acland, you are an absolute inspiration. Your teachings have followed me throughout my entire educational endeavor which has assisted me in publishing medical illustrations, anatomical dissections, and of course... research. Hat is off to you sir!

Hands down, without a doubt the greatest video I have seen explaining this topic. Amazing. thank you for sharing!

Thank you Dr. Acland! You are such an inspiration and you are truly missed!

Heart embryology simplified *1000x . Nothing else can beat this.

Hats off to all who made this. This is real gem. #Respect

This explanation is beyond amazing. Thank you!

One of the greatest videos ever made// Cant believe it was more than 60 yrs back.. Thanks for sharing! Proud to be the 1000th person to like it !

This is the best heart developement video. An it's so old! Also, Mr. Acland narrating this is just pure bliss

after watching many old videos explaining medical stuff, im more convinced that lecturers and companies explain everything in a bad way so students spend more on different resources, GREAT video thanks for sharing

Woahhh, it’s the best cardiogenesis video I have ever watched. Best explanation and animation even it is 70 years old!

Got tears in my eyes after watching this. For months i tried to understand this crap from books which was almost impossible to visualize, this video helped me understand that in a mere 10 minutes! God bless the person(s) who made this.

Thank you so much Dr. Acland for helping me understand gross and developmental anatomy. Your videos have made my studying so much easier!

omg 5 years in med school...and 3 in residency... nd i have never understood this...thank u thank u .... this is a really awesome, sensible and easy to understand aimation. i m gonna recommend it to everybody.

Absolute stunner. Timeless. This is so precious.

Dr. Acland - I really appreciate the video! Fetal cardiac development was this big scary monster to me, but this video has really helped me understand it! I have to admit I was totally lost watching this the first time, but after lecture, lab, and watching this several more times it makes sense now! As a visual learner who has trouble reading textbooks without pictures, thank you so much!

it's amazing what a good 10 mins of explanation can do, better then d hours I spent on daigrams

Thank you for this restoration which is the best 10 minutes I have spent understanding fetal heart development. Hands down best, clear, logical views of the sequence of events.

just 9:30 minutes to understand it .... and i spent 3 hours reading and reading !

This is the most beautiful thing to ever exist on the internet.

That was really helpful, thank you so much for going to all that effort to restore that film and turn it digital!

2022 and still nothing can beat this.

I usually don't comment but Sir , your video had compelled me to appreciate your effort . Marvellously explained ! Hats off !

thanks to dr ryan i found this video, thank you doctor rushmer and blandau whereever you are i hope yall are happy, you made our life easier. GOD BLESS

this will always be my favorite video on all of youtube

this is one of the coolest videos i've ever watched

wow....what a video. Just exquisite attention to detail with multiple angles and in perfect logical order. U don't find this kind of education anymore. I've LITERALLY never been able to understand heart embryology until now

Wow, what a lecture! Human body development is simply amazing, it's almost moving... life is incredible.

each and every second of this is gold.

Thank you, Doctor Acland! I'd recognise that voice anywhere. And even though you are no more, your voice guides me through my journey to becoming a doctor.

Oh my gosh, thank you soooo much! I love it when something finally makes sense!! Great explanation!

this is the best embryology video i have ever seen

Wow... Too amazing... After 4 yrs of medical School, i understand it now...

Hearty thanks for the team

Just about to start my cardio block in a few weeks time and was recommended to get a good grip on embryology early. So glad I found this, HOLY COW! Everything makes so much sense and it will be so much easier to understand cardio now 😭

Your soothing voice and careful enunciation calms my Cardiophysiology-induced rage. This is a wonderful resource and a far preferable alternative to confusing diagrams and cross-sections. Thank you so very much.

That's excellent as 100 books of anatomy of human heart and 1000 lectures about normal development of human heart

Jason Ryan sent me here

amazing animation !!!! made me understand in 9 min what 1 hour of lecture could not...

Sir you are a blessing. God Bless you. Being a MS 1 student, the challenges associated with the rigor of the material are there, but through your anatomy and youtube videos, you have made it easier. My roommates and I salute your efforts. Take care!

Such an iconic voice for medics , calms you and at the same time reminds you of all the times you slept when you were watching this in bed

Amazing video ! Very helpful. Perfectly presented. This video from 1951 is much better than any book of the present time.

Thank you so much for posting this.

The team involved in launching this masterpiece deserves bows, you are educating us for sure, maybe some teachers need to be educated about how to teach❤

Simple animation and clear explanation made life easy!Thank you so much

His voice is so relaxing... I felt so sleepy.

this video is so fun to watch, clear description...thank you 😊

This couldn't be better explained. Thank you so much

this is a work of art

This was so incredibly helpful! simplicity is the way to go!

explained in simplest and comprehensive way. Thankyou dr blandau !!!!

I have watched this 3 times, now is my 4th, and every time I watch it I think I understand everything there is to know about heart development. Until I forget it and need to watch it again, that is. Thanks from AUSTRALIA. Also, Bob Acland thanks for doing this remaster (I remember watching it a couple of years ago before you did this) and also please please bring out that Embryology video soon... I really really need it :)

Amazing!9 hours of complicated lecture into something easy to understand!Thanks a lot :)

i have finally cleared my doubts...thanks ...old is gold video

This is still better than some of the more contemporary explanations.

funny how a 1951 video explains this better than a 2020 lecturer

thank you so much for this clear description ... i have got a headache trying to understand what is written in the book ; but now it all came into my mind as simply as watching a cartoon

Very nice animation. Very clear explanation. Thank you for posting this!

10/10, such a fantastic resource.

THis is the best thing I've ever seen in my life!!!!!!!!!! whoever made this, may God give them tousand years to live")))

M really grateful to the Doctors for teaching it in such a beautiful yet so simply. It's Excellent! :)

this video is perfect, so clarifying!

one of the best videos on you tube

Truly Might be the best explanation ever !!!

Beautifully clear.

This is the most beautiful thing i have seen!

This video really explains every detail of development and circulation. I will be sharing with my class. Thanks for the great material

best heart development video ever

this video saved me so much time

Wow! Crisp and clear explanation. Thank you!

One of the great cardiology teaching videos .

Thank you so much for making me understand the complicated process

Best video on KZfaq on this topic

This video is gold.

You must be awarded with noble prize...what an animation...what a video..just anazing amazing and amazing...nothing to say😍😍

So sophisticated and clearly explained.

70 years later, i say thank you

This was such a huge help. Thank you.

thank you very muchhhhhh to those who did this😘

thank you so much for this video, amazing work!