The coronary arteries are the blood vessels that supply oxygenated blood to the heart itself. The main coronary arteries are large and in charge on the surface of the heart before branching out into smaller arteries that run through the rest of the heart muscle tissue. These smaller arteries eventually reconnect with each other and form a web or network that keeps the heart running.
The coronary arteries to the right supply the right ventricles of the heart – ventricles are large chambers in the heart that are responsible collecting blood and then expelling it out from the heart to where its needed. The left coronary armies branch off and similarly supplies blood to the left ventricle.
Why Bother With The Coronary Arteries?
As the blood vessels that supply blood to the heart muscle itself, any damage or disease that affects the coronary arteries has serious implications – this lack of blood results in a loss of nutrients, oxygen and removal of toxic metabolites. Atherosclerosis is the build up of plaque inside the artery that eventually leads to blockages and atherosclerosis of the coronary armies can lead to a heart attack and possibly death.
What Happens To The Coronary Arteries During EECP?
You see, the majority of coronary artery blood flow occurs when the heart itself is relaxed – in other words, between heart beats and pumps. This is because of where the coronary arteries originate within the heart itself. The positioning of the coronary arteries means that the contraction of the heart tissue itself results in a corresponding constriction of the arteries minimising flow. It is only when the tissue relaxes that the heart can get its own blood supply.
What this also means is that the absorption of oxygen occurs only when the heart is resting and relaxed in between beats when the coronary arteries and the heart tissue are filled with blood. This tells you that the absorption of oxygen is tied to the blood pressure in between heart beats – also known as the diastolic pressure.
What Does This Have To Do With EECP?
Well, the EECP system of pressure cuffs push blood up from the lower extremities between heart beats and thereby INCREASES the diastolic pressure. This increases the blood flow to the coronary arteries.