A Special Feature from Express Healthcare Management

ECP For Heart Artery Blockages: Ignored Far Too Long, Not Any More

By Dr (Col.) Kulwant Sharma, MD (Med), Neovask Heart Centre, Delhi

These are the words; on ECP; of the President of India and an eminent scientist, Dr APJ Abdul Kalam, in his address to the 2nd world congress on interventional cardiology at mumbai, held on 25 Feb. 2005: "We have all witnessed the treatment of cardiovascular disease moving from very invasive to less invasive methods. In the seventies bypass surgery was the big news, in the eighties it was balloon angioplasty and in the nineties it was the stent. Now, moving a step further is a totally non-invasive treatment -

EXTERNAL COUNTER PULSATION (ECP), a truly non-operative, non-pharmaceutical, safe and effective treatment, which has made big news in the west. ECP is FDA (USA) approved and finds reference in medical and cardiology textbooks. Many favourable articles have been published in the Journal of the American College of Cardiology, Cardiovascular Reviews Reports, Cardiology, Mayo Clinical Proc., Clinical Cardiology, Journal of Critical Illness, Journal of External Counter Pulsation, etc. The success of ECP can be judged from the fact that in USA the insurance sector reported that the reimbursement for ECP has gone up by 6 % whereas that of other procedure like angioplasty, bypass surgery, etc. has come down by 7%. Now the treatment is available in most of the leading hospitals of the world. It is well known that following bypass surgery - only 75% patients are symptom free for 5 years or more and only 50% after 10 years or more.

The number of patients having recurrence after bypass, ballooning and stenting is increasing and for them ECP is the only FDA approved treatment available which is documented to increases blood supply to the heart by 20-42%, to the brain by 22-26% and to the kidneys by 19%. ECP also increases heart's output. More patients now prefer non-invasive treatments. With improved cerebral circulation patients may notice improved memory, etc. This 2nd World Congress may like to study this technique of ECP EXTERNAL COUNTER PULSATION for providing non-invasive cardiac care."

Analysis of accumulated research data over the past more than three decades has revealed some very disturbing findings: when the outcomes of the people who underwent bypass operations and those who underwent angioplasty were compared with those of the people who refused to undergo any of these invasive/ surgical procedures, there was found to be hardly any difference. Almost the same number of people had suffered heart attacks and almost the same number of people died over the next ten years or more between the two groups.

Clearly, patients are not benefiting from CABG and PTCA. But bypass operations and Angioplasties are continuing to be performed with great flourish and in great numbers. Surely, at least some people must be benefiting? Yes, some indeed are benefited, but rarely they are patients and usually they are the hospitals and the doctors.

Extensive research has been conducted over the past few years to understand the reason behind this puzzling phenomenon-after all when blockages have been cleared away or bypssed and effective blood supply has been restored, why should heart attacks and deaths continue to take place more or less at the same rate as before? An answer came from the dead people-those who had died of heart attacks. Post Mortem examination of their hearts revealed that more than 85% of the deaths had taken place NOT because of physical obstruction caused by deposits, but they had been caused by "Plaque Rupture", that is, bursting of the covering membrane of the fatty mass leading to triggering of massive blood clotting locally.

Another interesting finding to emerge from Post Mortem examinations was that blockages are not a localized phenomena. They are generalized, affecting the entire length of coronary arterial tree; less at some places and more at others. If all the branches of coronary artery are arranged end-to-end, the resultant conduit will stretch for more than ten kilometers. Therefore, a bypass here and an Angioplasty (with a stent or two may be) there; will be a very truncated solution to a very complex problem. After these very disturbing findings surfaced, a crying need for some solution, which could tackle the problem across its daunting length & breadth began to be felt by all concerned.

When all these exciting things like CABG (Bypass), PTCA (Angioplasty) and "Stents" and "Drug Eluting Stents" were taking place, another development was going on quietly, in the field of "External Counter Pulsation". Research in this field started way back in 1953 and by mid seventies, the technique had been refined to such an extent that it had started showing promising results. But around the same time, the euphoria & hype created by Bypass and Angioplasty; due to their "glamour" and "quick fix" nature (and of course, very attractive scope for commercial exploitation); overshadowed this promising new technology. But over the years, the sky high hopes raised by CABG and PTCA were belied and further refinements in the ECP technology raised new hopes. Finally, External Counter Pulsation got approval of USFDA in 1995 for treatment of Angina Pectoris and subsequently for the treatment of Acute Myocardial Infarction (Heart Attack). Recently, it has even been approved for the treatment of Congestive Heart Failure.

This noninvasive technique provides augmentation of diastolic blood flow and coronary blood flow similar to the intra-aortic balloon pump, utilizing the serial inflation of three sets of cuffs which wrap around the calves, thighs and buttocks. Inflation and deflation are timed to the patient's ECG; which is fed into a computer and the arterial pressure waveform thus created is monitored noninvasively, by applying an electronic monitor either on an ear lobe or on one of the fingertips.

The overall effect on blood circulatory status is such that it provides augmentation of diastolic blood pressure (during the heart's resting phase). This leads to increase in coronary perfusion pressure. There is unloading of systolic (systole: heart's beating/ contracting phase) cardiac workload also and therefore decrease in myocardial (myocardium: heart muscle) oxygen demand. Venous return increases and as a result, cardiac output also improves. A course of treatment consists of 35 sessions of one hour each over a period of three to five seven weeks.

History of research in ECP is very interesting. It is a remarkably simple but smart idea. Researchers realized that heart gets its own blood supply during its resting phase, after supplying blood to the whole body during it's contracting phase. Accordingly, search started for a mechanism to increase pressure of blood column at root of the Aorta (the main artery carrying blood from the heart to supply the whole body). One such was "Intra Aortic Balloon Pump", wherein; a balloon was positioned at the root of the Aorta, by threading a catheter in through leg arteries, under x-ray monitoring. This balloon is then sequentially inflated and deflated through an external "Pulsator", which operates on the basis of ECG input from the patient and fires an inflation at the beginning of Diastolic phase and fires a deflation at the end of the diastolic phase.

This rhythmical inflation-deflation provides support to a week and failing heart. Taking a cue from IABP, two brilliant scientists, Soroff and Birtwell first described how the application of a positive pressure pulse to the lower extremities during diastole could raise diastolic pressures by 40 to 50% and lower systolic pressures by up to 30%. Herein, lower limbs are looked upon as if they are fluid filled bags, filled with at least one & a half liters of blood at any given time.

Lower limb and abdominal arteries are used as conduits or pipes to transmit pressure to root of the Aorta (When nature has given built in tubes to us in the form of arteries, why insert tubes from outside in the form of catheters?) Inflatable cuffs when made to inflate in a sequential manner as already described above, lead to 'milking' action on the blood column, resulting in formation of pressure wave traveling in retrograde fashion towards the heart.

State University of New York at Stony Brooks has conducted independent research and confirmed the efficacy and safety of ECP. Further boost to ECP has been given by the Multi-center Study of Enhanced External Counterpulsation (MUST-EECP) (Enhanced External Counter Pulsation-EECP is a brand name) research study. Results of this study were presented at the annual scientific meeting of the American Heart Association in November of 1997 and published. Seven centers enrolled into this study: University of California, San Francisco Moffitt-Long Hospitals; Columbia Presbyterian Medical Center; Yale New Haven Medical Center; and Beth Isreal Deaconess Hospitals of Harvard Medical School; University of Pittsburgh Medical Center, and Grant/ Riverside Methodist Hospitals of Columbus, Ohio. A recently conducted PEECH clinical trial presented at Annual Conference of the American College of Cardiology has also proved efficacy of ECP.

Unfortunately, commercial returns from ECP are comparatively low as compared with Bypass or Angioplasty, therefore leading hospitals, which happen to be posh corporate hospitals, are not keen to take ECP onboard. Public demand may spur them to do the needful.

Scientific research always leads from complexity to simplicity and from bigger to smaller and from more difficult to easier e.g. Radio, television, computer and all such things. Similarly the ease of use and simplicity of ECP is a marvel of scientific research and technology.

In the coming day, ECP is predicted to emerge as the treatment of choice for Coronary Artery Disease (Blocked heart arteries). Often people ask, "Why did it not occur to any one before?" But no idea ever surfaces before its time. The time of this smart new idea has now come.