What is the pericardium?
The pericardium is “a fibrous sac that attaches to the central tendon of the diaphragm and fuses with the adventitia of the great vessels superiorly.” The great vessels are the large blood vessels that carry blood to a from the heart. The adventitia is the outermost layer of the wall of a blood vessel. So, the pericardium is:
- A fibrous sac (two-walled, in fact, with fluid in the space between).
- Attached to the central tendon of the diaphragm (the main muscle of breathing).
- Fused with the outermost walls of the big blood vessels of the heart.
What does the pericardium do?
The pericardium has four functions.
- It protects the heart from infections,
- It protects the heart from knocks and jolts (this due to the fluid in the space between the two sacs),
- It lubricates the heart and
- It prevents excessive swelling of the heart in the case of a sudden increase in blood volume, which is usually associated with other illnesses or problems with sodium levels in the blood.
Unsurprisingly, given its roles, in Traditional Chinese Medicine, the pericardium is also referred to as the heart protector. The pericardium meridian runs down the inner arms, between the two tendons of the inner forearm, crosses the palm and then runs along the middle finger, terminating at its tip. Anyone who has treated secondary lymphoedema of breast cancer will observe that the affected areas coincide spectacularly with the pericardium meridian…
What happens to the pericardium during cancer treatment?
Fibrosis is the thickening and scarring of connective tissue usually as a result of injury. The injury in this case is a radiation burn. Bear in mind that there are diseases that cause a primary fibrosis (cystic fibrosis, for example). We are not talking about yoga therapy for such diseases here, although some of the underlying theory may be applicable. We are discussing yoga therapy for breast cancer patients who may have pericardium fibrosis caused by RT. This would be a secondary fibrosis, just at the lymphoedema seen in breast cancer patients is secondary to lymph node excision or what have you.
RT has a tendency to burn the surrounding tissue as well as the tumour. The pericardium is already defined as a “fibrous sac” and the fibrosity that can develop as a result of radiation burns is our main concern here. Bear in mind that different RT techniques will have greater or lesser probability of damaging the pericardium. I observe that women with deep tumours often have RT tattoos on the other side of the chest, meaning that at least one ray had to cross the chest the get to the tumour. Shudder. Indeed, this article (from 2010) says that 20% of oncology patients who have had RT in the chest develop constrictive pericarditis. This is called “radiation-induced constrictive pericarditis.” Constrictive pericarditis is a medical condition characterized by a thickened, fibrotic pericardium, limiting the hearts ability to function normally.
Let’s also take a moment to recall that chemotherapy often damages the heart.
Yoga poses for the pericardium.
Spinal extensions, backbends, outwards arm rotations, held inhales, arm raises with inhales and basically anything that stretches the chest and moves the diaphragm will be therapeutic for the pericardium. However, as usual, there are limitations and contraindications that must be considered. A glance at this page is useful in that it demonstrates a number of poses that quite frankly could not be used in the classes that I give.
Firstly, recall that fibrosis is not reversible. It can be improved and loosened, but under normal circumstances, it is chronic. I mention this to help you pace your program and not expect miracles. I also warn strongly that overwork and tears are not desirable. So, work within your students’ limits.
Referring back to the last page I mentioned, the “puppy dog pose” could be modified to a cat-cow sequence, breathing out with rounding the back and in when arching. Another typical viniyoga sequence is moving slowly between cat pose and child’s pose.
Another typical sequence is alternating between standing on the tiptoes with the arms reaching up (keep to shoulder height in some cases, elbows may also need to bend, ideal is palms facing at the top) and a half-squat with a spinal twist. If you alternate sides and breathe in when you go up and out when you go down, you get a really nice loosening effect in the mid-trunk without really running risk of injury.
What can be interesting is using breath retentions to increase the lung volume and mobilise the intercostal and the serratus anterior muscles. Next week I will post a sequence that I use and love. Right now, I have to go. It’s been a long post and I think that I have communicated what I set out to.
To yog is to live. Keep at it!!!