GaySexPedia: The Cardiovascular System

Why Should I Know This?

As with many areas of the body, it is good to know about the cardiovascular system because of the important contribution it plays in bodily function.

When engaged in kink activities, having even a rough understanding of where the arteries and veins of the body are can make a tremendous difference in the comfort and well being of the bottom. If you are playing with knives or any kind of blood play, this information becomes increasingly important or even if you are simply doing some bondage, this information can reduce the chance of constricted blood flow that can lead to numbness or unwanted discomfort.

What is the Cardiovascular System?

The cardiovascular system is made up of your heart, blood and blood vessels. This system uses your blood to deliver oxygen and nutrients to every area of your body as well as pick up waste products for disposal (Discovery Communications Inc, 2000).

Your blood pumps through two different channels: arteries or veins. Arteries are broad-walled tubes that are covered by yellow elastic fibers. The elastic fibers are filled with muscles that absorb the pressure waves from your heartbeat and slows your blood flow down; this pressure is commonly known as your pulse. Veins, in contrast, have thin and slack walls since your blood has already lost the pressure from your heartbeat and carries your deoxygenated blood back to your heart (HowToMedia, 1999).

Your Heart

While we have many sentimental ideas about our hearts and we know that they are vital to our survival, when you get right down to it the heart is an elaborate and complex pump (Bianco, 1998).
In the average lifetime, a heart beats over two and a half billion times and experiences no rest breaks (The Franklin Institute, 1996). The sound of your heartbeat is caused by the acceleration and deceleration of your blood as it moves through the various sections of this crucial organ (Bianco, 1998).

The heart is comprised of three layers: endocardium, myocardium, and pericardium. The endocardium is the inside lining of the heart while the myocardium is the middle layer. The pericardium is a fluid filled sac that surrounds the exterior (Bianco, 1998). Once inside the heart, this organ has four open spaces, or cavities, that your blood moves through; two of the cavities are atria while the other two are ventricles. The atria are the cavities that comprise the top curved portion of the heart and the ventricles form the bottom portion (The Franklin Institute, 1996).

Each cavity has a type of one-way valve which connects to the next section that keeps your blood from flowing backwards through your heart. When the cavity or chamber contracts, this valve exit opens and allows blood to move into the next heart cavity, closing the valve with the end of the muscle contraction so that the blood does not move back (Bianco, 1998).

Your heart pumps due to a specialized group of cells that are able to produce electrical activity independently. The heart has a natural pacemaker called the sinoatrial node which is located in the right atrium. This node conducts electrical impulses to the rest of the heart through unique fibers. The cells divide charged particles and then spontaneously release some charged particles into selected cells. This action occurs multiple times per second to cause an electrical impulse to spread over the heart and force it to contract to produce a normal heart beat of 72 beats a minute (Bianco, 1998).