Got together like love and marriage, like horse and carriage, like peanut butter and blue cheese.
I’ve long been interested in what I call ‘virtual relationships’ around the body. Places where things appear together to such an extent that they probably have to have some kind of symbiotic and functional relationship.
I also happen to have a passion for undertaking very detailed and fine dissections where I can spend time seeing how tissues both weave together and separate. It’s not something I generally have a lot of time to do in a class, and any opportunity to spend time alone in a dissecting room will find me undertaking a task on my long list of “I wonder ifs…”
The fibrous pericardium of the heart is generally shown as being continuous with the top of the diaphragm. In open heart surgery (as far as I can ascertain) the pericardium is opened and then not closed up. I presume because it will close itself. I haven’t been able to confirm this with a heart surgeon by the way, so any corrections will be gratefully received. This picture whilst showing the connection of the pericardium to the diaphragm, also happens to show the beauty of the blood vessel network and gossamer nature of this structure.
In any event the linking of the heart to the diaphragm tells us that every time we breath in and out 15-20,000 times a day, our heart rides up and down on our diaphragm, probably contributing to the momentum of heart movement and blood flow. From a geeky perspective I wondered as to the extent of this connection. Could the heart be separated from the diaphragm intact? After a few false starts and some holes in the pericardium, I managed to perfect this dissection which you can see here.
I regularly show how the fascia of the diaphragm is to all intents and purposes, continuous with the fascia of transversus abdominus and that there is also a continuation of the parietal pleura over the diaphragm and incidentally both these pictures don’t make clear that there is another lining over the top of the diaphragm which is parietal pleura. It’s pretty difficult to separate this although I have done it in sections. Perhaps another challenge?
What does it prove? I have yet to postulate any ideas regarding function, just that it is incredibly interesting and does show these two structures as complete and independent of each other from a biological standpoint. Sometimes the applications come after the demonstration possibility. A starting point would be to name the junction. Diaphragmatic pericardial raphe perhaps? Answers on a postcard please!