To survive a heart attack you first must understand what is actually happening to the body when a heart attack occurs.
What happens in a heart attack?
A sudden rupture in an unstable area of a wall in an artery leads to buildup of clot with often-total blockage of the artery. This cuts off the blood supply beyond that point. The heart muscle supplied by that artery now no longer gets the blood it needs, and dies, typically within a matter of hours. Every minute from when a heart attack starts is absolutely critical, often times STEMI heart attacks and NSTEMI heart attacks. Heart disease is the leading cause of death in the US, with almost one death a minute from coronary artery disease and heart attacks, but the good news is that there is progress being made. In-fact between 1970 and now there has been an almost 8 year increase in life expectancy, in large part due to improved treatment of coronary heart disease which of course includes heart attacks. It is also interesting to know that some heart attacks can be far worse than others (you may have heard of the infamous Widowmaker, and this can also determine the prognosis.
The Importance of Pre-Hospital Care – Call An Ambulance!
In the 1960’s it was realized that of people dying from heart attacks, over half died within an hour of the heart attack starting, and most of those deaths occurred before the patient even made it to hospital. So the concept of pre-hospital care was developed. When people die within that first hour, they typically die of ‘ventricular fibrillation’, which is basically a lethal heart rhythm leading to cardiac arrest. In order to survive this two things are critical. Firstly is the rapid administration of CPR (chest compressions and breaths) to allow blood to circulate around the body. Secondly is the administration of a shock from a defibrillator to restore the heart’s rhythm to normal. In the late 1960’s a paramedic group from Northern Ireland demonstrated nicely just how critical this is. They published an article showing that after establishing a cardiac ambulance service, they were able to prevent any deaths occurring on the way to the hospital, with several patients requiring successful resuscitation efforts. This is the reason why, when patients who think they may be having a heart attack ask if they or someone they know should drive them to a hospital, I say no! I tell them to call an ambulance as quickly as possible, because it’s a tried and tested way of keeping people alive.
We Used To Tell People To Just Lie Still In Bed!
So what about once the heart attack patient makes it to hospital? Until the 1950’s we had one treatment, and that was basically bedrest. Instead of restoring blood flow to the blocked artery we were telling patients to just lie down and let it happen, leaving the artery blocked and allowing the heart muscle to die! For up to 6 weeks, patients weren’t even allowed to turn without assistance, and patients were encouraged to avoid activities even as trivial as reading the paper or listening to the radio! Then in 1952 there was a paper published in a leading medical journal that showed if patients were allowed to sit in an armchair, rather than bedrest, they were more likely to survive hospital stay. Despite this, some people regarded this new treatment of letting people get up from bed as crazy with one commentator reportedly comparing this armchair treatment to an electric chair! Compare that to today where we often send people home in 1-2 days!
Then Came The Clot Busting Drugs
Then in the 60’s and 70’s significant progress was made. Something called fibrinolysis; basically clot-busting drugs were developed and refined for use in heart attacks. These drugs are given in to the blood stream, and work on the clot to break itdown and restore blood flow to the blocked vessel. There were limitations though. Blood flow in an artery was restored in around ½ of the blocked arteries only, and there was an increased risk of major bleeding complications, with up to 1% having a bleed in the brain, many of which would result in death. These drugs were good, but not good enough. There is still a role for these medicines in many places where patients cannot make it in time to a hospital equipped with more advanced technology.
The Angioplasty Revolution
Then even more progress, in the late 1970’s a major breakthrough was made that would revolutionize the way we treat heart attacks and improve outcomes. A procedure called angioplasty was done for the treatment of a heart attack. Angioplasty basically means that a small tube was advanced through the leg arteries to the arteries of the heart and a wire was advanced through the blockage, then a balloon was passed to the blockage and inflated, disrupting the blockage and restoring flow in the vessel. Through the 80’s and into the 90’s the procedure was refined and in a major study done in 1993 it was shown that blood flow could now be restored in 93% of blocked arteries and that compared to the use of clot busting medications this procedure resulted in lower rates of death, and essentially got rid of the risk of bleeding into the brain. Trial after trial showed that angioplasty saved more lives, decreased further heart attacks, and saved more heart muscle.
Stents That Save Lives
A major problem with the use of balloons in heart attacks was that the area would often block back up! So stents weredeveloped, they would be placed in the artery to keep it open, and they did better in terms of patient outcomes than balloons alone. The initial stents developed used to have the problem of blockages building back inside them, called restenosis. At this point drug eluting stents were developed, whereby the stent is coated with a medicine that prevents growth of tissue within it. These drug eluting stents basically eliminated the problem of restenosis. Placement of drug eluting stents during a heart attack has become the standard of care because they give superior short and long-term results.
Keeping The Blood Thin And Keeping The Heart Strong
The major piece of the puzzle in terms of the acute treatment of a heart attack was preventing the most feared complication of stent placement, called stent thrombosis, whereby a clot would develop within the stent, blocking off the whole thing. As progress was being made with the balloon and stent technology, drugs were developed to decrease clotting and thus prevent the clot that caused the heart attack getting bigger and also to prevent the formation of clots inside stents. These drugs resulted in improved procedure outcomes, and further decreased the rate of complications and death. At the same time, many trials have been conducted demonstrating the benefits of various medicines (ACE inhibitors and Beta-Blockers for example) given after a heart attack that can help to improve the functioning of the heart muscle and improve survival.
Why Are We Still Way Behind?
We had understood the process that underlies a heart attack, developed medicines to prevent further worsening of the clotting process that resulted from the heart attack, developed methods of opening up the artery with balloons and stents and made large steps to make sure the stent stays open by using drug covered stents in situations where there was risk of re-blockage of the stent, and using medicines to prevent clot formation within the stent. Despite this incredible progress, outcomes after a heart attack had only been further decreased by a few percent. So what now?
It all comes down to timing. The progress made above is incredible, however in the setting of a heart attack there is a commonly used phrase that is critical to the entire event; ‘time is muscle’. The amount of heart muscle damaged is proportional to the patient survival and also the quality of life. We can have all the technology in the world but if the heart muscle is dead by the time we start the procedure, then there’s little we can do! Currently, treatment of heart attacks with the above measures results in recovery of approximately 1/3rd of the affected muscle only.
The first few hours after the heart attack begins is the critical period, in this period, literally every second counts, and the quicker the blood flow restored and the treatment instituted, the better the chances of survival, and the better the chances of keeping the heart muscle alive. Furthermore, thanks to decades of progress in out of hospital care, with things such as CPR, defibrillators and improved training of paramedic staff, it is very rare to die out of the hospital once in the care of medical staff.
There has been a large effort to reduce the time taken to get the patient to the hospital and once in the hospital to get the patient to the procedure room to open up the artery. One of the big measures used to track this is called the door-to-balloon time. This is the time taken from the patient hitting the emergency room to the time taken to restore the blood flow in the artery by inflating the balloon. Hospitals are required to have a door-to-balloon time of less than 90 minutes. But lets say that it takes 2 hours for the patient to get to the hospital from the time the chest pain started, then 90 minutes to restore the blood flow. That’s 3 ½ hours, 30 minutes outside the critical period.
Now lets say the patient started having the chest pain and wasted no time in calling the ambulance. The ambulance crew gave appropriate treatment en route to the hospital and even activated the cardiology team ahead of time and the patient made it to the hospital in 1 hour. Then the team was ready to go as soon as the patient hit the hospital and were able to take the patient straight to the procedure room and restore blood flow in 30 minutes (many hospitals now have a door to balloon time of 60 minutes, some even less than this!). This time it took 1½ hours, well within the critical period giving the patient clear survival advantage and increasing the chance of a good outcome.
A Long Way To Go
Unfortunately we are way behind and many people still suffer very bad outcomes after their heart attacks. It starts with the patients themselves, who may be not realize their symptoms are of a heart attack and therefore delay calling for help. I’ve dealt with many patients, who present days after a heart attack in heart failure, when the heart muscle is already dead, and didn’t realize that the symptoms they had been having a few days ago were not indigestion but actually a heart attack.
Excellent paramedic services are available in many places and mean that most people that make it to the ambulance make it to hospital, however, once reaching the hospital there are often unnecessary delays in starting the appropriate medicines and initiating the sequence of events that results in the patient being taken for required procedures to restore the blood flow such as stent placement. This process is improving all the time and many ER departments are working closely with cardiologists to minimize delays.
Although there are several medicines that have been shown to improve outcomes after heart attacks, these are often not started sometimes due to lack of specialist care and sometimes due to lack of attention to detail. Unfortunately even though the medicines are started in hospital patients may not continue to take them despite their benefits (sometimes due to cost issues, but often due to just forgetting to refill them). Also heart attack patients often don’t realize that they are in the highest risk group for another heart attack if they don’t pay close attention to treating the risk factors that led to the event in the first place such as high blood pressure, cholesterol, physical activity, smoking and diabetes!
The Perfect Heart Attack
No heart attacks are good, but some can turn out better than others, and as I’ve outlined above this is not due to chance, but from years of progress in science and technology. The best thing is to prevent a heart attack happening in the first place. But if a heart attack occurs, the perfect sequence of events would be centered on saving as much time as possible. The patient would call the paramedics and would be taken to the hospital without delay with suitable medicines given en route. Once at the hospital no time would be wasted and the patient taken for a procedure with stent placement to restore the blood flow as soon as possible minimizing any permanent damage to the heart muscle. Then the patient would be started on and continue to take further medicines that have been shown to improve survival and quality of life in heart attack survivors. After that they would attend a cardiac rehabilitation program and follow up closely with a cardiologist and their primary care doctor with close attention paid to treating cardiac risk factors and working hard to prevent another event.