SURGERY OFFERS HOPE TO SOME HEART-DISEASE PA TIENTS

Press, Volume CXI, Issue 32637, 19 June 1971, Page 12

SURGERY OFFERS HOPE TO SOME HEART-DISEASE PA TIENTS

(By

KEN COATES)

If the reported success of surgeons in the United States, and the enthusiasm of cardiologists at Princess Margaret Hospital, Christchurch, are any indication, New Zealand stands on* the brink of making important decisions which may offer many heart di s eas e sufferers a chance of survival.

In essence, the new operation involves by-passing a blocked coronary artery by means' of a grafted section of vein from the patient’s ■ leg. And this restores immediately the vital blood flow to the ailing heart. The technique is obviously much more complicated than this. At present in New Zealand it is carried out only at Green Lane Hospital, Auckland, where Sir Brian BarrettBoyes pioneered heart surgery involving valve replacement.

And so far only 30 by-pass grafts have been done at Auckland.

According to a cardiologist, Dr F. T. L. Hull, of Princess Margaret Hospital, who worked with Dr W. D. Johnson, of Milwaukee, from 1967 to 1970, the method represents a very promising treatment which deserves to be explored further by New Zealand.

In the last 11 months, he says, more than 400 patients have been admitted to the hospital with coronary disease. Because it has the equipment and expertise to make an investigation on patients, using an X-ray movie technique, not done elsewhere in this country, the hospital has carried out special diagnoses on 65 patients. And 35 of these have been considered suitable for the new by-pass graft operation. But heart disease is a swift killer, and the unfortunate fact is that five of these patients are now dead. Dr Hull has returned from an international cardiology and cardiac surgery conference held a few weeks ago in Melbourne.

Present was an Argentinebom surgeon, Dr Rene Favaloro, aged 48, who joined one of America’s leading heart surgeons, Dr Donald Effler, at the Cleveland clinic in 1962 to study coronaryartery disease.

Intricate procedure

In an operation first performed four years ago, he removed a section of his patient's saphenous vein. This is a vein which runs the length of each leg; and the one removed in a varicous vein operation. It returns only about one tenth of the blood in the leg to the heart, so other veins can take over its work.

In an intricate by-pass procedure, he attached one end to the blocked right coronary artery at a point below the obstruction and stitched the other to the aorta, above the blockage. The procedure allowed blood to bypass the blockage and greatly improved the supply of blood to the heart.

The operation since then has been refined and perfected. The Cleveland Clinic alone has done nearly 2000 by-pass grafts. The procedure is medically termed revascularisation, dubbed popularly “replumbing” of the heart. It is re-

ported that Cleveland Clinic lost only four of 255 patients in "replumbing” procedures in February and March of this year, although the overall mortality rate for hospitals in the United States is 5 per cent. Of Dr Johnson’s revascularisation patients, 77 per cent are reported to have survived at least two years after their operations. Dr Hull quotes figures which show the success of Dr Favaloro who, between May, 1967, and March 1, 1971, performed 2371 saphenous vein grafts in 1756 patients (some patients have more than one graft). Operative mortality is less than 5 per cent, and in the last 230 operated on it has been less than 2 per cent. Follow-up studies show that 85 per cent of the grafts have remained effective—the longest follow-up period is three years three months. Of the first 300 patients operated on, only 16 died. More than 6700 people die each year from coronory heart disease (the figure for 1969 was 6665—an increase of 255 over the previous year).

Dr Favaloro says by-pass grafts can be performed on 80 per cent of patients with atherosclerosis— the build-up of hard, fatty deposits that narrow the coronary arteries and cut off the flow of oxygenated blood to the heart muscles.

Dr Hull says the percentage in this country could be somewhere between 40 per cent and 80 per cent. And he adds that it is significant that in Australia all the

major medical centres are gearing up for using the technique. A key procedure which must precede this type of surgery, and one which is the speciality of Dr Hull, is the use of X-ray movies which pin-point exactly where the blocked artery is. This system is termed cine coronary angiography. A catheter, or thin piece of tubing, is inserted into an artery and radiopaque dye is squirted into the coronary arteries.

The latest equipment enables doctors to see on X-ray movie film, with a high degree of accuracy, what is wrong and where. For years heart surgeons have been trying to find an effective way of improving the blood flow to the heart when a person suffers blocked coronary arteries. In 1945, Dr Arthur Vineberg, a Canadian, thought of using the internal mammary artery, which runs down the inside chest wall, as a new source of blood for a struggling heart. Its normal job is duplicated by other arteries, so it can be spared. Freed from attachments, the mammary artery was placed in a tunnel cut in the muscle wall of the left ventricle —the hardest working part of the heart which pumps blood out into the main trunk line, the aorta, and to the whole body. When so implanted, the mammary, after six weeks to six months, often hooks up with unblocked branch coronary arteries, and pro-

vides the heart with blood through a new network. But the major drawback with this procdure is time, and the patient may not last until the new blood flow can take effect.

However, combined with the by-pass graft technique, the mammary implant has a better chance of helping to improve the circulation of blood to the heart muscles.

Other surgeons have tried opening a blocked segment of coronary artery and reaming out the clogging material. Or they have slit the artery and grafted on a patch of vein. But all these procedures have their limitations.

“Best chance” American experts such as Dr Favatoro and Dr Donald Effler, of the Cleveland Clinic, believe that by-pass grafts, particularly when combined with mammary implants, are the ideal solution to most coronary conditions. Apart from Dr Hull's enthusiasm, there is in Christchurch a degree of caution, but general-agreement that on present evidence, the procedure offers the best chance of survival for patients with blocked coronary arteries. At present in New Zealand only a fraction of the patients who could possibly benefit from the technique are being operated on using the by-pass graft method. And it is estimated that between 1000 and 2000 patients could undergo the life-giving surgery. Add this to the estimate that 30 per cent of patients suffering from angina—that painful condition that often precedes a heart attack—and a good case can be made out for national consideration of trained personnel and facilities for this type of reconstructive heart surgery. At present in New Zealand there are two heart units—at State hospitals—in Green Lane Hospital, Auckland, and the other in Wellington. The need for an open heart unit at Christchurch seems clear, but what are the prospects of this? One of Britain’s leading cardiac surgeons, Mr P. J. Molloy, surgeon-in-charge at the Royal Victoria Hospital, Belfast, made a survey initially at the request of the Otago Hospital Board, and including the rest of the country at the request of the Health Department. His report and there commendations in it have not been published, but copies have been circulated. One copy has been sent to the North Canterbury Hospital Board, and the report has also gone to the Hospitals Advisory Council, Wellington. However, the report is being discussed unofficially and it is believed one, or possibly two new heart units are recommended. And it seems logical that with its much larger population, Christchurch, as the leading South Island city, should receive priority in the establishment of a heart unit. Much more, of course, is

needed than a heart-lung machine and the skilled technicians necessary to operate and maintain it.

As a hospital’s radiography department is vitally involved through the radiologist himself and equipment for carrying out X-ray assessments on patients, I talked with Dr J. B. Jameson, radiologist-in-chief to the North Canterbury Hospital Board. He describes the sort of assessment that is required before by-pass graft surgery is carried out as necessarily the ultimate in accuracy and quality. New equipment Equipment available at the time the hospital's heart unit was being set up in 1964 was certainly adequate at that time, but if the hospital was to carry out this work with the degree of accuracy and quality demanded for the best results, then it meant the latest equipment available today, he said. In other words, progress in this field has been so rapid that by overseas standards the present radiological equipment is out of date in this context. New equipment of an optimum standard would cost between $50,000 and $60,000. While this intricate operation is carrie dout, the heart must be stopped, and its function is carried out, the heart lung machine. Surgeons also must work fast —the longer the patient stays on the machine the greater the damage to his blood cells and the higher the risk of problems after the operation. But these machines are also expensive—something in the order of $50,000 each, plus an additional $lOO,OOO a year to the hospital's expenses in running and maintaing the unit.

Major killer Heart disease is a major killer in New Zealand. Medical opinion says some degree of prevention is provided by regular training, like running, but it is by no means unanimous or definitive. New Zealand prides itself on its national State hospital service, but the decision will have to be made sooner or later whether the money can be made available to include this new procedure in all major hospitals. Surgeons would have to be sent abroad for training in new techniques, or they could be brought to New Zealand to head teams in major centres. There is a risk with the procedure—all heart surgery, when it involves heart dis, ease, blocked arteries and damage to the system, is a touchy business. But when a man is say, in his thirties —and the age level for heart disease in New Zealand seems to be lowering—and there is a better-than-average chance he will benefit from a new surgical technique, then ethically there is little choice but to make every effort to provide it. And right now the hands of doctors in Christchurch are in this respect, tied.