Our body actually has two circulatory systems. While they work individually to perform their main functions, they also work together to some degree. One of these, the cardiovascular system, provides our body tissues with the needed oxygen, nutrients, and hormone-rich blood required for everyday functions. The other, the lymphatic system, rids our body of the waste products (including old red blood cells) produced during daily internal functions, thus protecting us from the harmful effects we would experience otherwise. In addition, the spleen (part of the lymphatic system) also serves as a blood reservoir for the cardiovascular system until the blood is needed.
How the Cardiovascular System is Related to the Lymphatic System
To understand how the cardiovascular system is related to the lymphatic system, we need to look at both of these symptoms more in depth. In the cardiovascular system, blood is the vehicle used to deliver oxygen, nutrients and hormones to the various muscle and organ tissues within the body. Arteries deliver this loaded blood into the various body parts, using capillaries for some of the delivery. Then, the veins return the depleted blood back to the heart for oxygenation again. While the kidneys serve as the main blood cleaning station in the body, removing waste and fluid excess from it, the lymphatic system also plays a role in the purifying of the blood. It removes the old red blood cells and any wayward blood that may have seeped into muscle tissues accidentally during transit through the body.
Lymphatic System Explained
As muscles and blood vessels within the body begin to move and function throughout the day (like from deep breathing activity or physical movement), waste products in the muscle tissues begin to seep into the lymph capillaries. This propelling of the muscle and organ tissue waste products into the lymph vessels aids the lymph in collecting and removing this type of waste, which sometimes contains blood that dissipated into the muscle tissues accidentally. As the waste passes by the lymph nodes located throughout the body, some debris (old red blood cells, for example) and excess fluids (as well as bacteria and cancer cells) are ingested by the lymph nodes' cells. Finally, after these waste products are removed, the remaining healthy lymph travels on to either the thoracic or right lymphatic ducts—located in the shoulder area—where it is then mixed with blood, so it can be returned to the heart for further use.
One Relationship Between the Two Systems: Waste Removal
One way there is a relationship between the cardiovascular and the lymphatic system is the fact that both systems have processes that rid the body of waste products, and these processes help to eliminate some of the same detrimental properties common to them both: old red blood cells, toxic waste and pathogens.
Relation of Capillaries and Vessels
Another relationship between both is the internal system of capillaries and vessels that basically parallel one another throughout the body: one working to provide nutrients and oxygen to muscles and organs; the other working to rid them of the waste produced. Although the capillaries and vessels for the cardiovascular system hold blood, and the lymphatic ones hold lymph, both systems work in unison with the same overall objective: maintaining the body's ability to function at an optimum level without hindrance of pathogens or detrimental waste.
Just as the cardiovascular veins have one-way valves in order to prevent blood backflow, the lymph vessels have one-way valves to prohibit backflow of lymph. This is yet another way that these two systems are similar to one another.