Immediate
Reperfusion
Our Revolution
in Acute Myocardial Infarction
The story of reperfusion in acute myocardial
infarction was one of the high points of my career. The thrill of a totally new
procedure is like a field of flower buds unfolding: the contents of the buds
are unknown but when they open, one has a beautiful new flower. Reperfusion
therapy was the new flower in the garden. Myocardial infarction has been conquered,
albeit partially, and has opened a new vista in cardiology. Mortality has
fallen, infirmity and disability have decreased and life prolonged in patients
who suffer from the number one killer in Western Society.
A myocardial infarct occurs when one of the
arteries (Coronary Artery) that supplies blood to heart muscle is blocked
suddenly. This deprives it of oxygen and the muscle cannot contract, becomes
stunned and within two hours it dies. The blockage occurs because cholesterol
accumulates in the vessel wall, narrows the lumen, the hillock ruptures, a clot
forms and the artery is occluded. This causes disturbances in heart rhythm
often with sudden death, or damage to the pump with severe shock and later
heart failure. The patient can die, suffer permanent disability or recover.
The new chapter in medicine started in 1954 when
Sol Sherry revolutionized the treatment of acute thromboembolic vascular
disease by dissolving a causative thrombus (clot) or embolus using the natural,
lytic drug, streptokinase. His group treated acute myocardial infarction, pulmonary
embolism, thrombophlebitis and peripheral arterial occlusion. (1959). He was
uncertain about the effect of lysis in myocardial infarction and stopped these
studies. The drug was approved for lysis in other thrombotic states in 1977 by
the FDA.
Acute myocardial infarction had been treated conventionally
by watchful expectancy, usually with three weeks rest in bed. (armchair rest treatment).
In 1965 I analyzed its mortality in a general hospital ward at Groote Schuur
hospital in Cape Town where we found it to be 34%. Our first revolution was to
introduce intensive coronary care with ECG monitoring of the ECG to control and
treat arrhythmias and more personalized care and nursing. In my first coronary
intensive care unit, one year later, the mortality dropped dramatically to 14%.
The pathologists had argued about the
pathogenesis (precipitating cause) of myocardial infarction. Was it due to
acute thrombotic occlusion of the coronary artery or to sudden coronary spasm
which caused long-term ischaemia (decreased blood supply) and myocardial
necrosis? Peter Rentrop from Göttingen summarized the status in 1977. Autopsy
studies in the mid-1960s provided fresh evidence that coronary thrombi were
common in acute myocardial infarction and that intimal fissuring of the
arterial intima (inner layer) caused both plaque haemorrhage and intraluminal
thrombosis. Bill Roberts, the premier pathologist from the NIH suggested the
plaque fissures were artefacts and resulting from sectioning arteries at
postmortem, and that coronary thrombosis resulted from a prolonged low output
state associated with large infarcts. European investigators continue to
explore the possibility of lysis of the thrombus in acute myocardial
infarction, although they believed that the lysis time for a coronary thrombus
exceeded the time limit of myocardial tolerance from anoxia. They hoped to
improve collateral flow (from other coronary arteries) and microcirculation by
lysis (dissolving) and opening of the capillaries and venules within and around
the infarct zone. The discussion about the pathogenesis of acute myocardial
infarction was limited by the inherent selection bias of autopsy studies and
the paucity of in vivo and angiographic data.
The great breakthrough took place when Earl Wood,
a surgeon in Spokane, Washington presented a cohort of patients in 1979 who had
undergone coronary artery bypass surgery to bypass the obstruction) and
compared them with a similar group who underwent regular medical therapy.
Mortally reduction was dramatic and improved in the patients treated early
(hours). Early surgical reperfusion had succeeded.
Rentrop continued his studies of reperfusion in
acute myocardial infarction, first using a wire to perforate the thrombus and
later controlled dissolution studies with Steptokinase. The results were very
successful and the clot in the coronary artery was successfully lysed, coronary
flow restored and myocardium salvaged. Rentrop then moved to New York and
started further studies in the United States. Marc Verstraete from Louvain in
Belgium organised working groups in Europe, at first using Steptokinase and
used mortality as his endpoint. Initially, the results were indifferent, but
gradually they improved. Genentech, a new biotech company cloned tissue
plasminogen activator (tPA) which is identical to the natural lytic (dissolving
protein) protein in the blood. It was a superior lytic drug and doubled the
reperfusion rates and the clinical results improved further. This aroused
excitement in Europe and several centres embarked on large controlled studies. Hugenholtz,
Simoons and van der Werf were real protagonists as was Harvey White in New
Zealand.
The new catch phrase in medicine in 1980 was
evidence-based medicine. This introduced the second phase of research –
randomized double blinded controlled studies - half of the patients were
treated with the new drug and the other half received normal accepted treatment.
Peter Sleight from Oxford was the British pioneer (GISSI Trial). Braunwald from
Harvard was the other leader and together with Passamani from the NIH set up
the first Thrombolysis In Myocardial Infarction (TIMI) study. All their
patients with an acute myocardial infarct had an initial coronary arteriogram (to
demonstrate the narrowings and blockages in the coronary arteries) and half
were given Steptokinase and the other half tPA. In patients with occluded
arteries the patency rate at 90 minutes was 62% with tPA and 31% with
Steptokinase. The trailblazing continued: TIMI progressed, and there were large
international and national trials in England, Germany, France, Holland and
Italy. It now became clear that early treatment within four hours of pain onset,
together with adjunctive anticoagulant and antithrombotic therapy, and
mechanical reperfusion improved the prognosis.
I heard Rentrop speak for the first time perchance
in Oslo in 1979, at a meeting on Timolol, a new beta-blocker drug for high
blood pressure, but which was also very effective for glaucoma. He was tall and
erect and spoke with a very impressive and forceful voice: he was very
convincing so that I realised that he had pioneered a new treatment, a real breakthrough
in the management of acute myocardial infarction. He had proved that it was
possible to lyse the thrombus using a thrombolytic drug. De Wood and his group
from Seattle had also just published their paper on the prevalence of total
coronary occlusion during the early hours of transmural myocardial infarction
in the New England Journal of Medicine: the results were very impressive. It
was now clear that 90% of these patients had complete thrombotic occlusion of
the culprit artery in the first hour after infarct onset and that there was
spontaneous thrombolysis in the following hours.
The obstruction set up a time dependent process
of myocardial necrosis in the anoxic zone and this was complete within 4 hours
of occlusion.
The pathologists, Reimer and Jennings tied off a
coronary artery in experimental dogs. They produced convincing microscopic sections
of the “wavefront theory” of muscle ischaemia, concussion and death, which
started soon after the occlusion and which was complete after 4 hours.
Prof Gabby Isaac, the head of Haematology at
Hadassah was using urokinase to lyse thrombi in the veins of the leg after deep
vein thrombosis and thrombi in the pulmonary artery in patients with acute
pulmonary embolism. He wanted to administer a direct bolus into the pulmonary
artery and recruited our help. The results of direct infusion through a
catheter were dramatic, the clot was lysed and disappeared, and the artery
reopened. I felt that the time had come to extend its use and infuse the drug
directly into the occluded coronary artery which was causing the acute
myocardial infarction
We started intracoronary lysis using urokinase. It was unbelievable to watch the lysis of the
clot in the culprit coronary artery during the infusion, relief of the intense
chest pain and the return of the ECG to normal.
Our first patient was a 73-year-old gentleman who had been admitted to
the internal medicine ward with severe unstable angina pectoris. I catheterised
him urgently on a Tuesday afternoon and demonstrated severe disease of all
three coronary arteries. We felt that he was a good candidate for coronary
artery bypass surgery. At 6 o’clock on Wednesday morning, he developed acute, severe
chest pain with ST segment elevation of the anterior cardiac leads on the ECG
and it was clear that he was developing a new myocardial infarction. The
surgeons had already started their two operations in the operating rooms, and
the patient’s family asked me if there was any way of unblocking the artery. I
had urokinase in the catheterisation laboratory and we brought him down for a
repeat coronary angiogram. The left anterior descending artery which previously
had a 90% obstruction, was now completely occluded, and there was no flow down
the artery. We infused the urokinase and it was amazing to see, how, after 15
minutes, contrast medium trickled into the occluded artery and after another 15
minutes there was rapid flow. The clot had been lysed, and flow restored. The
ST segment elevation on the ECG, started to disappear and then suddenly he had ventricular
fibrillation and a cardiac arrest. His blood pressure dropped to zero. Jacob,
our technician, defibrillated him immediately while Basil Lewis started artificial
ventilation. The resuscitation was successful, his blood pressure rose and I
could see the heart beating on the x-ray screen. At the same time, Prof
Eliakim, the head of internal medicine department, appeared at the door of the
catheterisation laboratory and said ‘Gotsman, how can you snatch the patient
from my ward without a formal discussion at the afternoon departmental
conference!” He watched the resuscitation and was really quite upset. At that
time I did not realise that the ventricular fibrillation was a reperfusion
arrhythmia due to oxygenated blood entering the anoxic myocardium. The patient
had a fairly small infarct, recovered uneventfully, later underwent a
successful triple vessel coronary artery bypass graft and lived for another 15
years. The thrombolytic reperfusion was dramatic and proved that we could open
the artery, restore blood flow and decrease the size of the infarct. The
paradigm had shifted.
The second patient was no less dramatic. He was
a 42-year-old director of finance of the local sick fund and came to tell me
that I was undertaking too many coronary angiograms and wasting part of his
budget. He felt a sudden pain, put his hand on his chest and then the pain
increased in intensity. I sat him down and gave him a coronary vasodilator. The
electrocardiogram showed ST segment elevation in the inferior leads, a sign of
an impending myocardial infarction. He had heard of our successful reperfusion
and asked me to take him to the catheterisation laboratory immediately. He had
a single, total occlusion of the right coronary artery and the obstructing
thrombus created a picture that looked as if the artery had been amputated. We
started an infusion of urokinase and within 15 minutes restoration of flow
started. It continued for another 30 minutes, the pain subsided, the ST segment
elevation disappeared and he asked for a cigarette. He recovered after a very
small infarct (heart muscle death) and was discharged home after a few days.
The patient continued to smoke,the
atherosclerosis in the coronary arteries continued to develop and later needed
and underwent several balloon dilatations. He is alive and well, some 30 years
later.
Teddy Weiss, my senior cardiologist at Mt
Scopus Hospital had returned from a post graduate Fellowship at Cedars Sinai
hospital in Los Angeles in 1984. Willie Ganz, the local proponent of
thrombolysis suggested that we use our mobile ambulances that were manned by a
physician as well as trained paramedics to use intravenous
Steptokinase for lysis and the best method of shortening the time delay from
pain onset to lysis was to initiate and administer the treatment at home before
transport to the hospital. Teddy undertook
the organization of the project. We were joined by Dr. David Applebaum who oversaw
the Magen David Emergency Ambulance Service.
The ambulance was staffed by a trained physician and supplementary
experienced ambulance staff and was equipped with ECG monitoring, an ECG
recorder and an external defibrillator. David
was a sterling and active protagonist. He trained and mentored a motivated team
who could arrive at the patient’s home with a median of 5 minutes from the
moment of call. They made an immediate diagnosis, treated any arrhythmias and
quickly transferred the patient to the receiving hospital. This service soon
became available throughout Israel. Unfortunately, David was murdered in a Palestinian
suicide bombing at Café Hillel in Jerusalem on September 9, 2003.
We turned this clinical service into a most exciting
and unusual research project and showed that it was possible to start
thrombolysis in a pre-hospital setting within one hour of pain onset. The
mortality was so low that we needed a more sensitive index of myocardial salvage
and infarct size. We had already studied left ventricular function in detail by
left ventricular angiography and we used infarct size to show that the this was
a function of time delay, and that death of the heart muscle was complete after
2 hours. Once pain started, the clock
started ticking and every minute of delay was crucial.
We were conquering acute myocardial infarction
and preserving heart muscle and function. At the same time, there were similar
studies in Rotterdam, Brussels, Paris and the rural areas around Aberdeen, in Scotland
and Belfast in Northern Ireland. We
invited our coworkers to a series of meetings to compare procedures and notes
and published a series of monographs.
I became known as “the cardiologist who ran
around the city with his ECG and syringe” opening coronary arteries in acute
myocardial infarction.
Basil Lewis and I had learned a great deal from
Hal Dodge and Florence Sheehan in Seattle about understanding global and
regional left ventricular function of the heart. We had used the computer to analyze the left
ventricular angiograms and had defined different patterns of contraction after
the obstruction of the different coronary arteries. It was simple to study
patients after thrombolysis to determine the extent of myocardial
infarction. We produced different models
of measuring left ventricular dysfunction and developed 3-dimensional
representations. The extent of
myocardial necrosis was related to the volume of muscle supplied by the
affected artery, the site of the coronary obstruction, the extent of the
collateral circulation and to the delay from pain onset to reperfusion. The
research produced at least 20 major publications and was the pivotal research
thrust of the department for the next 10 years.
Sima Welber joined us as a research fellow, and completed her MSc degree.
David Fine came from the Mayo Clinic and joined the research team but
after 2 years returned to practice in Minneapolis. He had to return a large
loan he had taken as a student. Teddy
Weiss was full of ideas and all the younger staff participated with great
enthusiasm.
We had shown that prehospital thrombolysis was very effective. Mortality had fallen to 2 ½%.
The most exciting of all the other studies was the Great study
undertaken by general practitioners in the rural Grampian region of Scotland,
near Aberdeen. The general practitioners were trained to make an initial
diagnosis of impending myocardial infarction and provide immediate
thrombolysis. Half of the patients were given APSAC (a streptokinase
derivative) at home and the other half on admission to hospital. Prehospital
initiation of thrombolytic therapy saved one hour (105 versus 240 minutes) and
was associated with halving of the three-month mortality (from 15.5% to 8%).
Besides the reduction in mortality there were fewer cardiac arrests, fewer
Q-wave MI’s, and improved left ventricular function. GP training improved the
speed of physician response, clinical assessment and diagnosis, relief of pain
and anxiety, correction of autonomic disturbances, and, arrhythmias, and
resuscitation. Telephonic transmission of the ECG via the general practitioner
to the regional hospital was the most effective approach in rural areas, before
the ambulance arrived. It is ideal where the local hospital is 1 to 2 hours
away from the patient.
Other randomised controlled studies such as the EMIP study in
France and the West Washington study in Seattle were less decisive because the
time delays were much longer.
There was a spate of major international studies that showed the
superiority of thrombolysis. We introduced new antithrombotic drugs but now we
had to be careful of excessive bleeding. The major problem was a small, but significant
group of patients who developed intra-cerebral haemorrhage.
I travelled abroad extensively discussing our results. The most
interesting experience occurred after I had spoken at the Friday morning
cardiology meeting in Seattle. The group had studied all the acute infarcts in
Seattle. Doug Weaver and Ward Kennedy who lead the randomized controlled studies
had excellent results with mortality reduction in the anterior infarcts but were
less successful with inferior infarcts. These infarcts in the inferior wall were
usually small, and their time delays too long to make a significant impact.
In Rotterdam the ambulance was also very active. In Belgium they
were using general practitioners and in rural northern Ireland the ambulance
was going out into the country. I was invited to develop thrombolytic programs in
Spain and Portugal and when the Iron Curtain came down eastern Europe started
to lead the field. The medical metamorphosis was complete. Poland and Hungary
were the first countries to implement the treatment. The countries had
cardiologists whose IQ’s were identical to Western Europe but they had been deprived
of adequate financial budgets. The opening of the intellectual gates, the cross
communication of information with the Western countries and their extreme
enthusiasm took then out of the darker ages into a new intellectual sunshine
and while it took a generation to eliminate the old communistic bureaucracy,
the drug and medical device companies discovered a fertile field for research
and supported new projects and the medical machine of progress escalated.
Eric Topol, a young dynamic cardiologist from Ann Arbor, started a
series of major multicentered international mega trials (TAMI and GISSI trials).
He showed that thrombolytic treatment with TPA was very effective. Eric was a
most impressive physician. He would enter the lecture theatre with his little
bag and give a most exciting presentation. I went to visit him in Ann Arbor, and
found that he was doing 7 to 8 catheterisation studies a day in addition to his
clinical load and research studies. He moved to Cleveland clinic as director of
cardiology and then director of the clinic and eventually moved on to San
Diego. Braunwald was the father of myocardial salvage and mortality reduction continued
with his TIMI studies, andhe and his group continued to introduce new
supplementary thrombolytic regimes to improve the reperfusion and prevent
further reocclusion and showed that not only opening the artery and
re-establishing flow but also re-establishing the micro circulation was very
important. They used mortality as endpoints whereas we used infarct size.
The next innovation was to use immediate coronary angiography to
define the coronary anatomy, followed by immediate balloon dilation in order to
accelerate opening of the artery more rapidly and completely. This was
pioneered by Cindy Grines and Bill O’Neill in the Beaumont Hospital in Royal
Oak, Michigan. She was a tall, thin, athletic lady, always on the move and with
a very intense work ethic. She would come to the hospital immediately at night
and run a 24-hour, seven-day a week service and was prepared to catheterize
patients with acute myocardial infarction at any time of the day or week. She
started a series of PAMI studies to compare treatment with immediate balloon
angioplasty to thrombolysis. She reduced the mortality from 10% percent to 2%
and re-infarction within six months from 16 to 8%. There was a gradual
acceptance of her new technology, and within five years virtually all the
patients with acute infarction were being treated by percutaneous coronary
interventions. Stents were introduced, followed by drug, eluting stents, and
the long-term results were excellent. Once again, the paradigm had shifted.
We also entered the field of emergency 24 hour per day angioplasty
and because of the new DRG, which reimbursed the hospitals for the extra work
and cost, larger than the previous
payments for angioplasty, the hospital found it profitable to undertake these
procedures and we now have two on duty residents and two senior cardiologists
on-call. Our mortality also plummeted and within two years the system had been
introduced throughout Israel. The patient calls the ambulance, who radios to
the on-call hospital, contacting the cath lab immediately and we try to have a
door to balloon time of under one hour.
Percutaneous Coronary Intervention (PCI) in acute myocardial
infarction is quite different from PCI in chronic coronary artery disease.
Acute myocardial infarction is an active process in which a coronary artery has
been occluded, part of the myocardium has been destroyed and many of the
patients come to the catheterisation laboratory, cold and shocked, with a low
cardiac output and poor tissue perfusion. The patient needs immediate acute
intensive care, to raise the BP, improve the cardiac output and often to use
mechanical support such as an intra-aortic balloon pump, or inserting a
temporary pacemaker. In many patients the artery must be opened quickly but the
artery is filled with fresh thrombus. The balloon dilatations can cause distal
embolisation as the clot breaks off and fills the distal capillary bed with
clot. The operator’s need greater experience and more manual dexterity and a
sharp eye – brain – finger interaction and the ability to take immediate
lifesaving procedures. We tried aspiration of the clot through the catheter but
it did not improve outcomes.
A typical example is a 40-year-old man who has blocked his left
anterior descending artery and may have disease in his other coronary arteries.
He comes into the cath lab with a low blood pressure of 50/30, cold, pale and
sweating. He needs immediate intravenous fluids and often needs immediate
insertion of an intra-aortic balloon to support the circulation. The catheter
lab staff are working under extreme pressure and it is essential to open the
artery without delay. This may happen at 2 o’clock in the morning where
everybody has been summoned from their beds and the entire catheter lab team is
shifted into top gear. If the patient develops ventricular fibrillation, he needs
resuscitation, defibrillation and intensive drug therapy.
The Cardiac Department at Tel Hashomer Hospital under the guidance of
Shimon Behar and The Israel Cardiac Society started a national registry (ACSIS)
and the country-wide mortality has dropped progressively to 4% .
Non–transmural infarction was also upgraded and early
interventional procedures undertaken. The workload in our department changed
completely and since there were very few patients who developed restenosis, the
workload changed and most of the patients are admitted directly from the
emergency room.
The department now runs a 24/7 cath lab service. The mortality has
dropped dramatically and in more than 70% of the patients we salvage most of
the myocardium at risk.
There remain many unresolved issues: training the population to
call the emergency services earlier when chest pain starts, reducing the time
delay from pain onset to reperfusion, better methods of preventing myocardial
damage, management of large or second infarcts with cardiogenic shock, use of
new auxiliary pumps to assist the heart in shocked patients, and management of
patients with prolonged cardiac arrest and severe anoxic brain damage.
Nonetheless we have excellent new methods for centralized, cloud based
monitoring services, to manage high risk ambulatory patients and anticipate the
heart attack, internet communication between the ambulance and the receiving
hospital cardiac service and more immediate response using neighborhood
motorcycle response systems.
I can look back on this complete revolution,
from a 34% mortality with a 3-week rest in bed program, to 3-4% by immediate emergency
restoration of normal coronary flow in less than 2 hours of occlusion by a
well-trained ambulance service and an efficient
coronary catheterisation team of trained interventional cardiologists, technicians
and nurses.
I am proud of our energy, push, research and
enthusiasm and the continued vitality of my dynamic successor, Prof Chaim Lotan
and his hyperactive crew.
The sun never sets on
cardiology: the lights on the cardiology floor never dim at night.
Immediate
Reperfusion
Our Revolution
in Acute Myocardial Infarction
The story of reperfusion in acute myocardial
infarction was one of the high points of my career. The thrill of a totally new
procedure is like a field of flower buds unfolding: the contents of the buds
are unknown but when they open, one has a beautiful new flower. Reperfusion
therapy was the new flower in the garden. Myocardial infarction has been conquered,
albeit partially, and has opened a new vista in cardiology. Mortality has
fallen, infirmity and disability have decreased and life prolonged in patients
who suffer from the number one killer in Western Society.
A myocardial infarct occurs when one of the
arteries (Coronary Artery) that supplies blood to heart muscle is blocked
suddenly. This deprives it of oxygen and the muscle cannot contract, becomes
stunned and within two hours it dies. The blockage occurs because cholesterol
accumulates in the vessel wall, narrows the lumen, the hillock ruptures, a clot
forms and the artery is occluded. This causes disturbances in heart rhythm
often with sudden death, or damage to the pump with severe shock and later
heart failure. The patient can die, suffer permanent disability or recover.
The new chapter in medicine started in 1954 when
Sol Sherry revolutionized the treatment of acute thromboembolic vascular
disease by dissolving a causative thrombus (clot) or embolus using the natural,
lytic drug, streptokinase. His group treated acute myocardial infarction, pulmonary
embolism, thrombophlebitis and peripheral arterial occlusion. (1959). He was
uncertain about the effect of lysis in myocardial infarction and stopped these
studies. The drug was approved for lysis in other thrombotic states in 1977 by
the FDA.
Acute myocardial infarction had been treated conventionally
by watchful expectancy, usually with three weeks rest in bed. (armchair rest treatment).
In 1965 I analyzed its mortality in a general hospital ward at Groote Schuur
hospital in Cape Town where we found it to be 34%. Our first revolution was to
introduce intensive coronary care with ECG monitoring of the ECG to control and
treat arrhythmias and more personalized care and nursing. In my first coronary
intensive care unit, one year later, the mortality dropped dramatically to 14%.
The pathologists had argued about the
pathogenesis (precipitating cause) of myocardial infarction. Was it due to
acute thrombotic occlusion of the coronary artery or to sudden coronary spasm
which caused long-term ischaemia (decreased blood supply) and myocardial
necrosis? Peter Rentrop from Göttingen summarized the status in 1977. Autopsy
studies in the mid-1960s provided fresh evidence that coronary thrombi were
common in acute myocardial infarction and that intimal fissuring of the
arterial intima (inner layer) caused both plaque haemorrhage and intraluminal
thrombosis. Bill Roberts, the premier pathologist from the NIH suggested the
plaque fissures were artefacts and resulting from sectioning arteries at
postmortem, and that coronary thrombosis resulted from a prolonged low output
state associated with large infarcts. European investigators continue to
explore the possibility of lysis of the thrombus in acute myocardial
infarction, although they believed that the lysis time for a coronary thrombus
exceeded the time limit of myocardial tolerance from anoxia. They hoped to
improve collateral flow (from other coronary arteries) and microcirculation by
lysis (dissolving) and opening of the capillaries and venules within and around
the infarct zone. The discussion about the pathogenesis of acute myocardial
infarction was limited by the inherent selection bias of autopsy studies and
the paucity of in vivo and angiographic data.
The great breakthrough took place when Earl Wood,
a surgeon in Spokane, Washington presented a cohort of patients in 1979 who had
undergone coronary artery bypass surgery to bypass the obstruction) and
compared them with a similar group who underwent regular medical therapy.
Mortally reduction was dramatic and improved in the patients treated early
(hours). Early surgical reperfusion had succeeded.
Rentrop continued his studies of reperfusion in
acute myocardial infarction, first using a wire to perforate the thrombus and
later controlled dissolution studies with Steptokinase. The results were very
successful and the clot in the coronary artery was successfully lysed, coronary
flow restored and myocardium salvaged. Rentrop then moved to New York and
started further studies in the United States. Marc Verstraete from Louvain in
Belgium organised working groups in Europe, at first using Steptokinase and
used mortality as his endpoint. Initially, the results were indifferent, but
gradually they improved. Genentech, a new biotech company cloned tissue
plasminogen activator (tPA) which is identical to the natural lytic (dissolving
protein) protein in the blood. It was a superior lytic drug and doubled the
reperfusion rates and the clinical results improved further. This aroused
excitement in Europe and several centres embarked on large controlled studies. Hugenholtz,
Simoons and van der Werf were real protagonists as was Harvey White in New
Zealand.
The new catch phrase in medicine in 1980 was
evidence-based medicine. This introduced the second phase of research –
randomized double blinded controlled studies - half of the patients were
treated with the new drug and the other half received normal accepted treatment.
Peter Sleight from Oxford was the British pioneer (GISSI Trial). Braunwald from
Harvard was the other leader and together with Passamani from the NIH set up
the first Thrombolysis In Myocardial Infarction (TIMI) study. All their
patients with an acute myocardial infarct had an initial coronary arteriogram (to
demonstrate the narrowings and blockages in the coronary arteries) and half
were given Steptokinase and the other half tPA. In patients with occluded
arteries the patency rate at 90 minutes was 62% with tPA and 31% with
Steptokinase. The trailblazing continued: TIMI progressed, and there were large
international and national trials in England, Germany, France, Holland and
Italy. It now became clear that early treatment within four hours of pain onset,
together with adjunctive anticoagulant and antithrombotic therapy, and
mechanical reperfusion improved the prognosis.
I heard Rentrop speak for the first time perchance
in Oslo in 1979, at a meeting on Timolol, a new beta-blocker drug for high
blood pressure, but which was also very effective for glaucoma. He was tall and
erect and spoke with a very impressive and forceful voice: he was very
convincing so that I realised that he had pioneered a new treatment, a real breakthrough
in the management of acute myocardial infarction. He had proved that it was
possible to lyse the thrombus using a thrombolytic drug. De Wood and his group
from Seattle had also just published their paper on the prevalence of total
coronary occlusion during the early hours of transmural myocardial infarction
in the New England Journal of Medicine: the results were very impressive. It
was now clear that 90% of these patients had complete thrombotic occlusion of
the culprit artery in the first hour after infarct onset and that there was
spontaneous thrombolysis in the following hours.
The obstruction set up a time dependent process
of myocardial necrosis in the anoxic zone and this was complete within 4 hours
of occlusion.
The pathologists, Reimer and Jennings tied off a
coronary artery in experimental dogs. They produced convincing microscopic sections
of the “wavefront theory” of muscle ischaemia, concussion and death, which
started soon after the occlusion and which was complete after 4 hours.
Prof Gabby Isaac, the head of Haematology at
Hadassah was using urokinase to lyse thrombi in the veins of the leg after deep
vein thrombosis and thrombi in the pulmonary artery in patients with acute
pulmonary embolism. He wanted to administer a direct bolus into the pulmonary
artery and recruited our help. The results of direct infusion through a
catheter were dramatic, the clot was lysed and disappeared, and the artery
reopened. I felt that the time had come to extend its use and infuse the drug
directly into the occluded coronary artery which was causing the acute
myocardial infarction
We started intracoronary lysis using urokinase. It was unbelievable to watch the lysis of the
clot in the culprit coronary artery during the infusion, relief of the intense
chest pain and the return of the ECG to normal.
Our first patient was a 73-year-old gentleman who had been admitted to
the internal medicine ward with severe unstable angina pectoris. I catheterised
him urgently on a Tuesday afternoon and demonstrated severe disease of all
three coronary arteries. We felt that he was a good candidate for coronary
artery bypass surgery. At 6 o’clock on Wednesday morning, he developed acute, severe
chest pain with ST segment elevation of the anterior cardiac leads on the ECG
and it was clear that he was developing a new myocardial infarction. The
surgeons had already started their two operations in the operating rooms, and
the patient’s family asked me if there was any way of unblocking the artery. I
had urokinase in the catheterisation laboratory and we brought him down for a
repeat coronary angiogram. The left anterior descending artery which previously
had a 90% obstruction, was now completely occluded, and there was no flow down
the artery. We infused the urokinase and it was amazing to see, how, after 15
minutes, contrast medium trickled into the occluded artery and after another 15
minutes there was rapid flow. The clot had been lysed, and flow restored. The
ST segment elevation on the ECG, started to disappear and then suddenly he had ventricular
fibrillation and a cardiac arrest. His blood pressure dropped to zero. Jacob,
our technician, defibrillated him immediately while Basil Lewis started artificial
ventilation. The resuscitation was successful, his blood pressure rose and I
could see the heart beating on the x-ray screen. At the same time, Prof
Eliakim, the head of internal medicine department, appeared at the door of the
catheterisation laboratory and said ‘Gotsman, how can you snatch the patient
from my ward without a formal discussion at the afternoon departmental
conference!” He watched the resuscitation and was really quite upset. At that
time I did not realise that the ventricular fibrillation was a reperfusion
arrhythmia due to oxygenated blood entering the anoxic myocardium. The patient
had a fairly small infarct, recovered uneventfully, later underwent a
successful triple vessel coronary artery bypass graft and lived for another 15
years. The thrombolytic reperfusion was dramatic and proved that we could open
the artery, restore blood flow and decrease the size of the infarct. The
paradigm had shifted.
The second patient was no less dramatic. He was
a 42-year-old director of finance of the local sick fund and came to tell me
that I was undertaking too many coronary angiograms and wasting part of his
budget. He felt a sudden pain, put his hand on his chest and then the pain
increased in intensity. I sat him down and gave him a coronary vasodilator. The
electrocardiogram showed ST segment elevation in the inferior leads, a sign of
an impending myocardial infarction. He had heard of our successful reperfusion
and asked me to take him to the catheterisation laboratory immediately. He had
a single, total occlusion of the right coronary artery and the obstructing
thrombus created a picture that looked as if the artery had been amputated. We
started an infusion of urokinase and within 15 minutes restoration of flow
started. It continued for another 30 minutes, the pain subsided, the ST segment
elevation disappeared and he asked for a cigarette. He recovered after a very
small infarct (heart muscle death) and was discharged home after a few days.
The patient continued to smoke,the
atherosclerosis in the coronary arteries continued to develop and later needed
and underwent several balloon dilatations. He is alive and well, some 30 years
later.
Teddy Weiss, my senior cardiologist at Mt
Scopus Hospital had returned from a post graduate Fellowship at Cedars Sinai
hospital in Los Angeles in 1984. Willie Ganz, the local proponent of
thrombolysis suggested that we use our mobile ambulances that were manned by a
physician as well as trained paramedics to use intravenous
Steptokinase for lysis and the best method of shortening the time delay from
pain onset to lysis was to initiate and administer the treatment at home before
transport to the hospital. Teddy undertook
the organization of the project. We were joined by Dr. David Applebaum who oversaw
the Magen David Emergency Ambulance Service.
The ambulance was staffed by a trained physician and supplementary
experienced ambulance staff and was equipped with ECG monitoring, an ECG
recorder and an external defibrillator. David
was a sterling and active protagonist. He trained and mentored a motivated team
who could arrive at the patient’s home with a median of 5 minutes from the
moment of call. They made an immediate diagnosis, treated any arrhythmia and
quickly transferred the patient to the receiving hospital. This service soon
became available throughout Israel. Unfortunately, David was murdered in a Palestinian
suicide bombing at Café Hillel in Jerusalem on September 9, 2003.
We turned this clinical service into a most exciting
and unusual research project and showed that it was possible to start
thrombolysis in a pre-hospital setting within one hour of pain onset. The
mortality was so low that we needed a more sensitive index of myocardial salvage
and infarct size. We had already studied left ventricular function in detail by
left ventricular angiography and we used infarct size to show that the this was
a function of time delay, and that death of the heart muscle was complete after
2 hours. Once pain started, the clock
started ticking and every minute of delay was crucial.
We were conquering acute myocardial infarction
and preserving heart muscle and function. At the same time, there were similar
studies in Rotterdam, Brussels, Paris and the rural areas around Aberdeen, in Scotland
and Belfast in Northern Ireland. We
invited our coworkers to a series of meetings to compare procedures and notes
and published a series of monographs.
I became known as “the cardiologist who ran
around the city with his ECG and syringe” opening coronary arteries in acute
myocardial infarction.
Basil Lewis and I had learned a great deal from
Hal Dodge and Florence Sheehan in Seattle about understanding global and
regional left ventricular function of the heart. We had used the computer to analyze the left
ventricular angiograms and had defined different patterns of contraction after
the obstruction of the different coronary arteries. It was simple to study
patients after thrombolysis to determine the extent of myocardial
infarction. We produced different models
of measuring left ventricular dysfunction and developed 3-dimensional
representations. The extent of
myocardial necrosis was related to the volume of muscle supplied by the
affected artery, the site of the coronary obstruction, the extent of the
collateral circulation and to the delay from pain onset to reperfusion. The
research produced at least 20 major publications and was the pivotal research
thrust of the department for the next 10 years.
Sima Welber joined us as a research fellow, and completed her MSc degree.
David Fine came from the Mayo Clinic and joined the research team but
after 2 years returned to practice in Minneapolis. He had to return a large
loan he had taken as a student. Teddy
Weiss was full of ideas and all the younger staff participated with great
enthusiasm.
We had shown that prehospital thrombolysis was very effective. Mortality had fallen to 2 ½%.
The most exciting of all the other studies was the Great study
undertaken by general practitioners in the rural Grampian region of Scotland,
near Aberdeen. The general practitioners were trained to make an initial
diagnosis of impending myocardial infarction and provide immediate
thrombolysis. Half of the patients were given APSAC (a streptokinase
derivative) at home and the other half on admission to hospital. Prehospital
initiation of thrombolytic therapy saved one hour (105 versus 240 minutes) and
was associated with halving of the three-month mortality (from 15.5% to 8%).
Besides the reduction in mortality there were fewer cardiac arrests, fewer
Q-wave MI’s, and improved left ventricular function. GP training improved the
speed of physician response, clinical assessment and diagnosis, relief of pain
and anxiety, correction of autonomic disturbances, and, arrhythmias, and
resuscitation. Telephonic transmission of the ECG via the general practitioner
to the regional hospital was the most effective approach in rural areas, before
the ambulance arrived. It is ideal where the local hospital is 1 to 2 hours
away from the patient.
Other randomised controlled studies such as the EMIP study in
France and the West Washington study in Seattle were less decisive because the
time delays were much longer.
There was a spate of major international studies that showed the
superiority of thrombolysis. We introduced new antithrombotic drugs but now we
had to be careful of excessive bleeding. The major problem was a small, but significant
group of patients who developed intra-cerebral haemorrhage.
I travelled abroad extensively discussing our results. The most
interesting experience occurred after I had spoken at the Friday morning
cardiology meeting in Seattle. The group had studied all the acute infarcts in
Seattle. Doug Weaver and Ward Kennedy who lead the randomized controlled studies
had excellent results with mortality reduction in the anterior infarcts but were
less successful with inferior infarcts. These infarcts in the inferior wall were
usually small, and their time delays too long to make a significant impact.
In Rotterdam the ambulance was also very active. In Belgium they
were using general practitioners and in rural northern Ireland the ambulance
was going out into the country. I was invited to develop thrombolytic programs in
Spain and Portugal and when the Iron Curtain came down eastern Europe started
to lead the field. The medical metamorphosis was complete. Poland and Hungary
were the first countries to implement the treatment. The countries had
cardiologists whose IQ’s were identical to Western Europe but they had been deprived
of adequate financial budgets. The opening of the intellectual gates, the cross
communication of information with the Western countries and their extreme
enthusiasm took then out of the darker ages into a new intellectual sunshine
and while it took a generation to eliminate the old communistic bureaucracy,
the drug and medical device companies discovered a fertile field for research
and supported new projects and the medical machine of progress escalated.
Eric Topol, a young dynamic cardiologist from Ann Arbor, started a
series of major multicentered international mega trials (TAMI and GISSI trials).
He showed that thrombolytic treatment with TPA was very effective. Eric was a
most impressive physician. He would enter the lecture theatre with his little
bag and give a most exciting presentation. I went to visit him in Ann Arbor, and
found that he was doing 7 to 8 catheterisation studies a day in addition to his
clinical load and research studies. He moved to Cleveland clinic as director of
cardiology and then director of the clinic and eventually moved on to San
Diego. Braunwald was the father of myocardial salvage and mortality reduction continued
with his TIMI studies, andhe and his group continued to introduce new
supplementary thrombolytic regimes to improve the reperfusion and prevent
further reocclusion and showed that not only opening the artery and
re-establishing flow but also re-establishing the micro circulation was very
important. They used mortality as endpoints whereas we used infarct size.
The next innovation was to use immediate coronary angiography to
define the coronary anatomy, followed by immediate balloon dilation in order to
accelerate opening of the artery more rapidly and completely. This was
pioneered by Cindy Grines and Bill O’Neill in the Beaumont Hospital in Royal
Oak, Michigan. She was a tall, thin, athletic lady, always on the move and with
a very intense work ethic. She would come to the hospital immediately at night
and run a 24-hour, seven-day a week service and was prepared to catheterize
patients with acute myocardial infarction at any time of the day or week. She
started a series of PAMI studies to compare treatment with immediate balloon
angioplasty to thrombolysis. She reduced the mortality from 10% percent to 2%
and re-infarction within six months from 16 to 8%. There was a gradual
acceptance of her new technology, and within five years virtually all the
patients with acute infarction were being treated by percutaneous coronary
interventions. Stents were introduced, followed by drug, eluting stents, and
the long-term results were excellent. Once again, the paradigm had shifted.
We also entered the field of emergency 24 hour per day angioplasty
and because of the new DRG, which reimbursed the hospitals for the extra work
and cost, larger than the previous
payments for angioplasty, the hospital found it profitable to undertake these
procedures and we now have two on duty residents and two senior cardiologists
on-call. Our mortality also plummeted and within two years the system had been
introduced throughout Israel. The patient calls the ambulance, who radios to
the on-call hospital, contacting the cath lab immediately and we try to have a
door to balloon time of under one hour.
Percutaneous Coronary Intervention (PCI) in acute myocardial
infarction is quite different from PCI in chronic coronary artery disease.
Acute myocardial infarction is an active process in which a coronary artery has
been occluded, part of the myocardium has been destroyed and many of the
patients come to the catheterisation laboratory, cold and shocked, with a low
cardiac output and poor tissue perfusion. The patient needs immediate acute
intensive care, to raise the BP, improve the cardiac output and often to use
mechanical support such as an intra-aortic balloon pump, or inserting a
temporary pacemaker. In many patients the artery must be opened quickly but the
artery is filled with fresh thrombus. The balloon dilatations can cause distal
embolisation as the clot breaks off and fills the distal capillary bed with
clot. The operator’s need greater experience and more manual dexterity and a
sharp eye – brain – finger interaction and the ability to take immediate
lifesaving procedures. We tried aspiration of the clot through the catheter but
it did not improve outcomes.
A typical example is a 40-year-old man who has blocked his left
anterior descending artery and may have disease in his other coronary arteries.
He comes into the cath lab with a low blood pressure of 50/30, cold, pale and
sweating. He needs immediate intravenous fluids and often needs immediate
insertion of an intra-aortic balloon to support the circulation. The catheter
lab staff are working under extreme pressure and it is essential to open the
artery without delay. This may happen at 2 o’clock in the morning where
everybody has been summoned from their beds and the entire catheter lab team is
shifted into top gear. If the patient develops ventricular fibrillation, he needs
resuscitation, defibrillation and intensive drug therapy.
The Cardiac Department at Tel Hashomer Hospital under the guidance of
Shimon Behar and The Israel Cardiac Society started a national registry (ACSIS)
and the country-wide mortality has dropped progressively to 4% .
Non–transmural infarction was also upgraded and early
interventional procedures undertaken. The workload in our department changed
completely and since there were very few patients who developed restenosis, the
workload changed and most of the patients are admitted directly from the
emergency room.
The department now runs a 24/7 cath lab service. The mortality has
dropped dramatically and in more than 70% of the patients we salvage most of
the myocardium at risk.
There remain many unresolved issues: training the population to
call the emergency services earlier when chest pain starts, reducing the time
delay from pain onset to reperfusion, better methods of preventing myocardial
damage, management of large or second infarcts with cardiogenic shock, use of
new auxiliary pumps to assist the heart in shocked patients, and management of
patients with prolonged cardiac arrest and severe anoxic brain damage.
Nonetheless we have excellent new methods for centralized, cloud based
monitoring services, to manage high risk ambulatory patients and anticipate the
heart attack, internet communication between the ambulance and the receiving
hospital cardiac service and more immediate response using neighborhood
motorcycle response systems.
I can look back on this complete revolution,
from a 34% mortality with a 3-week rest in bed program, to 3-4% by immediate emergency
restoration of normal coronary flow in less than 2 hours of occlusion by a
well-trained ambulance service and an efficient
coronary catheterisation team of trained interventional cardiologists, technicians
and nurses.
I am proud of our energy, push, research and
enthusiasm and the continued vitality of my dynamic successor, Prof Chaim Lotan
and his hyperactive crew.
The sun never sets on
cardiology: the lights on the cardiology floor never dim at night.
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