EECP Treatment Advantages and Disadvantages

Enhanced external counterpulsation (EECP) is a mechanical form of treatment for angina (chest pain).

While several clinical studies appear to show that this treatment can help reduce symptoms of angina in people with coronary artery disease (CAD), EECP has yet to be accepted by most cardiologists and has not entered mainstream cardiology practice.

What Is EECP?

EECP is a mechanical procedure in which long inflatable cuffs (like blood pressure cuffs) are wrapped around both of the patient’s legs. While the patient lies on a bed, the leg cuffs are inflated and deflated synchronously with each heartbeat.

The inflation and deflation are controlled by a computer, which uses the patient’s electrocardiogram (ECG) to trigger inflation early in diastole (when the heart relaxes and is filled with blood), and deflation just as systole (heart contraction) begins.

The inflation of the cuffs occurs sequentially, from the lower part of the legs to the upper, so that the blood in the legs is “milked” upwards, toward the heart.

EECP has at least two potentially beneficial actions on the heart:

• First, the milking action of the leg cuffs increases the blood flow to the coronary arteries during diastole. (Unlike other arteries, coronary arteries receive their blood flow in between heartbeats, not during them.)
• Second, by deflating just as the heart begins to beat, EECP creates something like a sudden vacuum in the arteries, which reduces resistance in the blood vessels of the legs so that blood can be pumped more easily from your heart. It is also speculated that EECP may help reduce endothelial dysfunction.

EECP also may improve peripheral arterial function, which serves to reduce myocardial oxygen demand.

How Effective Is EECP?

Several studies suggest that EECP can be quite effective in treating chronic stable angina.

A small randomized trial showed that EECP significantly improved both the symptoms of angina (a subjective measurement) and exercise tolerance (a more objective measurement) in people with CAD. EECP also significantly improved quality-of-life measures compared to placebo therapy.

Other studies have shown that the improvement in symptoms following a course of EECP seems to persist for up to five years (though 1 in 5 patients may require another course of EECP to maintain their improvement).

How Does EECP Work?

The mechanism for the apparent sustained benefits seen with EECP is unknown. Some evidence suggests EECP can help induce the formation of collateral vessels in the coronary artery tree by stimulating the release of nitric oxide and other growth factors within the coronary arteries.

There's also evidence that EECP may act as a form of “passive” exercise, leading to the same sorts of persistent beneficial changes in the autonomic nervous system that are seen with real exercise.

Can EECP Be Harmful?

EECP can be somewhat uncomfortable but is generally not painful. In studies, the large majority of patients have tolerated the procedure quite well.

However, not everyone can have EECP. You probably should not have EECP if you have:

• Aortic insufficiency
• Recent cardiac catheterization
• Irregular heart rhythm such as atrial fibrillation
• Severe hypertension (high blood pressure)
• Peripheral artery disease involving the legs
• A congenital heart defect
• Hypertrophic cardiomyopathy
• Valvular disease
• Enlarged heart
• A pacemaker
• Pulmonary hypertension
• Heart rate over 120 beats per minute
• History of deep venous thrombosis

For anyone else, the procedure appears to be safe.

When EECP Is Recommended

Based on what we know so far, EECP should be considered in anybody who still has angina despite maximal medical therapy, and in whom stents or bypass surgery are deemed not to be good options.

Medicare has approved coverage for EECP for patients with angina who have exhausted all their other choices.

In 2014, several professional organizations finally agreed in a focused update that EECP ought to be considered for patients with angina that's not helped by other treatments. These organizations are:

• The American College of Cardiology
• American Heart Association
• American Association for Thoracic Surgery
• Preventive Cardiovascular Nurses Association
• Society for Cardiovascular Angiography and Interventions
• The Society of Thoracic Surgeons

Why Isn’t EECP Used More Often?

The cardiology community has largely chosen to ignore such an unconventional form of therapy, and many cardiologists fail to even consider offering EECP as a therapeutic option. Consequently, most people with angina never hear about it.

That's unfortunate, as it doesn't seem unreasonable to allow patients with stable angina to opt for a trial of a noninvasive therapy, perhaps even before they are pushed into invasive therapy, when:

• A noninvasive treatment exists
• It's safe and well tolerated
• It's supported by available evidence (albeit imperfect) that strongly suggests the treatment is quite effective in many
• Those being treated can tell pretty definitively whether it substantially reduces angina symptoms