EECP Mode of Action

Detail about mechanism of action of EECP, ECP. Mode of action and information about, How it actually works.

 EECP Mode of Action

Enhanced External Counter Pulsation (EECP) is a non-invasive way of assisting circulation which is rapidly coming to replace bypass surgery in many cases involving angina pectoris. It is a treatment for ischemic heart disease which improves heart function by enhancing circulation through the coronary vessels using a pressure suit which fits the lower half of the body.

"Enhanced" refers to the equipment that has evolved over decades of research and development to become the state-of-the-art treatment delivery system now used in EECP treatment centers. "External" means that treatment happens outside of the patient's body and doesn't require surgery.

The system compresses the legs from the ankles through the thighs and (optionally) buttocks sequentially by inflating three sets of flexible, fabric cuffs during the resting phase of the heart cycle (diastole). This results in the movement of blood from the legs toward the heart through both the arterial and the venous systems. Pressure is applied with the timing and duration of each pulse and is synchronized with the patient's heart beat. This transmits back pressure through the arterial system.

In other words, each wave of pressure is electronically timed to a heart beat, so that the increased blood flow is delivered to the heart at the precise moment it is relaxing. When the heart begins to contract again, pressure is released instantaneously. This lowers resistance in the blood vessels of the legs so that blood may be pumped more easily from the heart, decreasing the amount of work required of the heart muscle. During counterpulsation the EECP system pumps when the heart is resting and releases pressure when the heart is contracts.

The aortic valve, the valve located at that point where the blood leaves the large (left) ventricle, prevents back flow into the left ventricle. The coronary arteries come off the aorta just above the aortic valve so that the increased diastolic pressure which results from the counter pulsations applied to the lower extremities drives extra blood through the coronaries, thus expanding networks of tiny
auxiliary blood vessels, thereby increasing the amount of blood flowing to heart muscle. The therapeutic benefit which is seen over time is that new blood vessels form creating a natural bypass. This is thought to occur due to the release of "angiogenic" (i.e. vessel forming) growth factors.

The result of EECP is to speed up a process which is already happening: the development of collateral circulation. This is, however, a gradual process.

 Step 1 Inflation initiates retrograde pulse wave
 Step 2 Inflation of lower thigh cuffs-50ms later

Step 3 Inflation of upper thigh cuffs-50ms later
Step 4 Deflation facilitates cardiac unloading



The typical treatment regimen for chronic angina patients is 35 hours of treatment, usually one hour per day, five for days per week for seven weeks. Some patients choose a 2-hour per day regimen, which reduces the time to completion to 3-1/2 weeks. Treatment can be given lasting up to four hours, with a 10 minute rest period after each hour of treatment. The duration of treatment and rest intervals will depend on the patient's condition, the degree of diastolic augmentation obtained, patient tolerance and the indications for application of the device.