Coronary Artery Bypass Surgery

Coronary artery bypass surgery, was a game changer in the treatment of heart disease and a major  positive disruptive technology which improved, preserved and lengthened the lives of patients with coronary artery disease,

I first learnt about coronary angiography at the Karolinska hospital in Stockholm in 1968. I had been invited by the Elema company to study their angiographic techniques using a large film changer to obtain exquisite and precise high definition images of the heart and its chambers. The radiologists were using an interesting technique of non-selective injections of contrast medium into the root of the aorta. The patient was anaesthetized, and a coiled catheter placed in the aortic root. Ventilation was interrupted, the cardiac output fell as did the blood pressure and then a large injection of contrast medium was made into the aorta. The contrast medium filled the coronary arteries, ventilation and the normal circulation were resumed, and excellent X-ray images were obtained of the coronary arteries.

Mason Sones at the Cleveland Clinic made the first direct coronary angiogram by accident. A cardiac catheter slipped into the coronary artery, contrast material was injected, the coronary arteries were opacified and the patient recovered. He refined his technique and soon was undertaking routine coronary angiography. Floyd Loop, the surgeon, was performing many Vineberg procedures, where the internal mammary artery was implanted into an ischaemic region of the heart muscle, which was not receiving sufficient blood because of a coronary artery obstruction. Mason Sones would then perform selective angiography and show that the internal mammary artery branches had connected to the branches of the obstructed coronary arteries. He had acquired a series of more than 2000 patients and had a vast experience in understanding the anatomy and disease in the coronary arteries.

Coronary artery surgery for atherosclerotic disease has undergone many changes.  First, the pericardium was opened and abraded (roughened) so that on healing small anastomoses were created between the parietal and visceral layers to improve coronary blood flow (Claude Beck). Vineberg in Toronto took down the internal mammary artery and implanted it into a tunnel in the ischaemic myocardium where it generated its own collaterals and this had been proven to be very effective at the Cleveland clinic by Donald Effler and then subsequently proven by angiography by Mason Sones

The coronary arteries were very small – 2 to 4 mm in diameter, but at first the surgeons tried to put patches across the  the narrowing to widen the arteries. This was only moderately successful.

The next step was to use open heart surgery  and support the heart using a heart-lung machine. A large superficial vein from the leg was harvested and used to bypasss the narrowing. The first anastomosis (connection) was to the aorta and the second to the narrowed or obstructed artery beyond the narrowing. Blood flowed through the bypass vein to supply the artery beyond the narrowing. The patient recovered, and his angina disappeared. A man who was unable to walk up a hill was restored to a normal lifestyle. Unfortunately, only very sick patients were selected for the operation. They had very diffuse disease with multiple narrowing’s in several arteries. They had also experienced several heart attacks so that the muscle of the heart had been replaced by a large scar. The post operative recovery was slow and the initial mortality was high. The cardiologists were not keen on sending their patients to an operation with a high mortality and a long recovery period. However Favaloro and Floyd Loop at the Cleveland Clinic, and Dudley Johnson in Milwaukee persisted, and gradually the results improved. They had excellent documentation and followup of their patients but showed that avanced age, multiple lesions and poor ventricular function carried a poorer prognosis.

I faced a different problem. I had learned how to do high quality coronary angiography but my surgeon, Chris Barnard in Cape Town was unhappy to with this microscopic surgical technique, so that I used my first coronary angiograms to exclude coronary disease in older  patients with valve disease before surgery.

I moved to Durban and was joined by Basil Lewis and Avi Bakst. We built a new catheter lab which had a 9 inch image intensifier that gave us a large field ventriculogram, and a second 5 inch intensifier which had greater magnification and produced beautiful cine pictures of the coronary arteries, its branches and the disease processes. Ben le Roux, an excellent surgeon was unwilling to tackle the microsurgery of the coronary arteries and we had to wait until we were joined by Mike Rogers, who had trained with Donald Ross at the National Heart Hospital in London, where he had undertaken the first coronary artery bypass grafts in England. Mike Rogers introduced the bypass graft operation in Durban and with his usual enthusiasm and surgical ability our program took off and flourished.

Basil and I travelled to the United States once a year, and would stop over at the Cleveland Clinic, and in Milwaukee. We continued to learn all the tips and tricks for improving the quality of our angiography and spent hours in the operating room watching the details of coronary artery bypass grafting and then following the patients after surgery in the clinic. Their angina pectoris had disappeared, and they returned to normal life. Their post operative coronary angiograms showed a normal graft filling a diseased artery with contrast medium. The operative problem was being solved.

In Durban our program flourished We now undertook more coronary artery bypass grafting on less severely diseased patients. The South African cardiologists were very impressed and excited by this impressive and revolutionary operation. They followed their patients in the clinic after coronary artery bypass surgery: their angina pectoris had disappeared, and they were living a normal life. The cardiologists started referring patients, but unfortunately most of them had very severe advanced disease.

We changed our research program to study the different patterns of coronary artery disease, their infarcts, their electrocardiograms, their clinical status and we built up a new classification of localized and diffuse disease and its syndromes that appeared after narrowing or obstruction of the left anterior descending, circumflex and right coronary arteries. We became more selective in  our patients, operative mortality fell, the clinical improvement was more marked after surgery and the results outstanding. Patients were referred from all parts of South Africa and now we had a problem with the Provincial Administration about the payment of fees since we were a free government hospital. Later  Rob Kinsley returned from the Mayo Clinic and started bypass surgery in Johannesburg, and a new generation of cardiac surgeons emerged in South Africa, but mostly in the private sector.

When I came to Jerusalem in 1973, coronary artery bypass surgery, was in its infancy, the coronary angiography was of poor quality and the surgeons had little experience.

I drove the program forward with my usual high energy enthusiasm.and soon we became the most active unit in the country and together with good surgery by Joe Borman and his younger colleagues we built up a large reservoir of patients with excellent short and long term surgical and clinical results.

Initially, Joe was a little conservative so that some of our very difficult and complicated  patients were sent to Floyd Loop in Cleveland, Johnson in Milwaukee, and to Green at NYU.  This was a tricky time as the internal medicine physicians were unwilling to submit their patients to surgery. The morbidity and mortality rates continued to fall and we had a flood of patients from all corners of Israel.  The sluice gates had opened.

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After 20 years coronary artery surgery had become the major full-time occupation of the cardiac surgeons. All the major hospitals in Israel followed suite and now have flourishing and  successful coronary artery bypass surgery programs.

 The next development was to protect the myocardium and provide a quiet operative field during the operative procedure. The heart was stopped, and we used hypothermia and direct coronary perfusion to preserve coronary blood flow and oxygenation. Myocardial preservation became a major goal. This was achieved by using potassium infusions into the coronary arteries, that would stop the heart and provide a quiet field for anastomosing the tiny arteries and then use other drugs and electrolyte solutions during the  preservation period. Reperfusion of the coronary arteries with warm blood and then defibrillation restored a beating heart. We restarted the heart but in a few patients there was myocardial damage. Joe Borman undertook extensive investigation of the preservation solutions in his animal laboratory.

We also discovered that the venous grafts had a finite lifespan. About 20% closed shortly after the operation, because of a poor anastomosis, a poor run off causing  low flow with clotting, or the grafts twisted in the pericardial space.

Some of the veins were not healthy or could not withstand the high arterial pressure and developed a reactive fibrosis and closed within the first year. In a third group, the risk factors for atherosclerosis continued to affect the native arteries, the atherosclerotic process developed in the grafts, and we learned that management of risk factors for atherosclerosis was a lifelong intervention and that patients with high blood levels of LDL soon developed graft atherosclerosis. Floyd Loop preferred to use bilateral internal mammary artery implants, the grafts remained patent: the long term results after 10-20 years were excellent. The other arterial grafts from the arm or abdomen were less successful, but as the implant technology improved, so did the long term outcomes.

The next stage was operating  on the beating heart without using the heart-lung machine: “off bypass surgery”. The chest was opened, and all the the anastomoses were undertaken on the beating heart, often at a reduced heart rate using short-term beta blockers. This was more difficult. The left anterior descending artery, on the anterior surface of the heart was easy to anastomose, the circumflex artery was located on the side of the heart, and to expose it, it had to be brought out of the chest and the heart rotated and brought forward. The right coronary artery was more difficult. It was located at the back of the heart and the heart had to be bent and  lifted forward for exposure. We overcame all these problems, but myocardial protection remained the simplest procedure.

Then came minimal invasive surgery using mini thoracotomies and working under telescopic vision. Recovery was rapid causing less discomfort to the patient.

I immersed myself and all my younger colleagues in coronary artery disease, studied all the  techniques at meetings in the US and Europe and spent many hours  in the operating room observing the leading surgeons in Europe and the USA. We also invited them to join us in Jerusalem and operate in Hadassah.

Initially the CABG procedures were treated with skepticism but as the results improved, major multicenter double-blind controlled trials were undertaken to compare medical and surgical treatments. The surgical group had better symptomatic and quality of life outcomes.

Percutaneous coronary angioplasty entered our repertoire in the early 1980’s: a simple technique of improving coronary artery blood flow and  myocardial perfusion without opening the chest and performing a major operation. We again led the way. Most centres would undertake a coronary arteriogram in patients with symptomatic coronary artery disease, return them to the ward, discuss the outcome and then decide whether the patient should be treated with conservative medical treatment or undergo PTCA or CABG. We decided to make the diagnosis at the time of catheterization and then continue to PTCA if indicated. When in doubt we would  consult with the duty cardiac surgeon and have a detailed discussion. If the PTCA was complicated we would consult with another senior interventional cardiologist and decide on the details of proposed interventions. The only problem was that the cardiologist was the gatekeeper in making the decisions. The entire department soon developed an intimate knowledge of the pathophysiology of the disease and became experts in the research literature and guidelines of treatment. The patients from the other major centers  in Israel, underwent an initial  diagnostic test and while waiting for a delayed clinical decision would consult with me and often ask me to undertake the interventional procedure in Jerusalem. This added a major workload but provided my group with extensive practical interventional experience.

Some patients deteriorated after about 10  years because of further progression of the underlying disease or development of graft atherosclerosis. We undertook the follow-up of these patients and became experts in understanding and prediction of the danger signs and introducing an early second round of interventions. Our program of careful clinical follow, liberal use of non-invasive tests to detect early signs of disease progression and then not delaying a second procedure to keep the patients in fine fettle. We relieved suffering and prolonged life. As the medical management and drug intervention  improved fewer and fewer patients needed reintervention and life was prolonged almost indefinitely. This placed a heavy clinical burden on myself and my staff.

The hospital administration  did not or would not recognize this revolution. I moved my own clinic outside the hospital where I could extend my day and see patients until 10 or 11PM in the evening. Unfortunately, this impinged on my research times and writing was often deferred to the early hours of the morning.

Joe Borman was a tireless surgeon and undertook meticulate anastomoses so that his grafts remained open for many years. His operating times were prolonged, but this was reflected in the long term symptom free survival of his patients. When he retired and Gideon Merin took over from him, the surgical wards were expanded and we doubled our patient throughput, but many of the patients needed a second operation after about ten years due to graft degeneration or progression of the underlying disease.

There was gentle competition between the cardiologists and the surgeons about who should intervene, and whether surgery was preferable to PCI and many trials were undertaken to compare the outcomes of the two competing procedures and frequent new modified guidelines were published. We maintained a friendly and congenial coexistence, as major clinical trials tried to determine which procedure was superior in the different patient subsets Earlier interventions and vigorous secondary prevention of disease progression also improved the long-term outcomes.

Robotic surgery entered the playing field and although some of the American and European surgeons have excellent results, we never entered the arena.

The hospital administration failed to understand the importance of our cardiological program and long-term rehabilitation, and we lagged in providing appropriate facilities.  My own relationships with the hospital administration became strained and I became known as the “octopus” who thought  that he owned the hospital. It is sad that we moved into adequate new facilities only when a new hospital director was appointed 17 years after my retirement as the Head of the unit. The Director, Prof Zeev Rotstein together with the Hadassah ladies and the Irma and Paul Milstein foundation have now provided adequate space and excellent facilities for the expanding service but unfortunately  most of the my fiery enthusiasm has abated.

Primary and secondary prevention programs are essential to limit the development of atherosclerosis. They have slowed the development of the disease so that severe atherosclerotic disease is disappearing, the disease has become less common and with almost universal opening of obstructed coronary arteries during acute infarction, there are less total obstructions and the patients have more suitable anatomy for later PCI or CABG.

The cardiac surgeons have played a lifesaving role in the management of coronary artery disease and have been my closest partners. Now we are taking over their function with simpler percutaneous techniques.Nonetheless there remain many patients with severe disease who need surgery.

I am very proud of catalyzing coronary artery bypass surgery and the overall management of coronary artery disease in South Africa and Israel.

It has been a  lifelong project of persistence and perservation and over last 15 years we have reduced the mortality of Cardiovascular Disease in Israel by 63 %.