Monday, June 06, 2011

STANDARD OF CARE - HEART ATTACKS


As I alluded to in the last article, I thought I should post a series of standards of care, maybe every monday, so that the general public can know what to expect when they have to consult a doctor with the acute emergency. I have chosen emergency situations because that is when you must trust the doctor as there is often not much time to discuss many of the pressing issues. An emergency is when a life is at stake, and time is of the essence. If something is not done right, right away, the patient could die.
Heart attack is the number one killer in the country and it kills many of those in the 40-55 age group ( people at the peak of their career, with families to support ), and so their loss is very severely felt. One third of patients with a heart attack dies. The mortality rate is high. Fortunately, there is much that medical science and cardiology can offer, in terms of saving the life.A heart attack occurs when a plaque ( an accumulation of cholesterol material in the arterial wall, covered over by a thin lining ) cracks ( the thin lining ruptures ), exposing the cholesterol crystals below to the blood flowing on top of it. Cholesterol is thrombogenic and so a blood clots, almost instantly and blocks off the whole artery, thereby depriving the heart muscle of vital life - sustaining blood and so the heart muscle in the affected area dies, within minutes ( 20 minutes or so ), and circulation should be restored within 4 hours for maximal benefit.
Because of the death of heart muscle cells, TIME IS MUSCLE. The longer we wait around, the more muscle will die. To salvage the heart muscle, is to restore the artery circulation, to revascularise. We can revascularise in too ways.
1. With the use of chemical agents, drugs, called clot - busters, or thrombolytics. These agents will eat away the blood clot, and so re-establish a tiny channel for blood to flow. The success rates are in the 70-90%, depending on which agent you use and how long you wait before seeking treatment. The longer you wait, the harder the blood clot, the more damaged the muscle, and so the less the success. Any secondary or tertiary care hospital can have access to these drugs, and so this method is available to many in the community.
2. With the use of balloon catheters and stents. With the balloon, we can clear away the the blood clot, and also the cholesterol accumulation at the site, and so with can restore circulation very effectively. This is usually followed by the use of a stent, which reduces complications and also makes the passage more permanent by reinforcing the vessel wal. However, this method requires a technically skilled team, and may not be available at all hospital, except in selective tertiary care cardiac centers. Angioplasty does have its risk and so cannot be undertaken by untrained specialist. With a trained team, the success rate is 90-95%, again depending on when the patient presents ( how long after the onset of chest pains ), and also how long the center takes to assemble the angioplasty team. We like to re-establish blood flow, within 4 hours if possible, at worse before 8 hours. Any longer, the risk of procedure may outweigh the benefit ( meaning that you are not saving much muscle, but still taking the risk of the procedure ). we call this approach, primary angioplasty for AMI. It is also costly, but it is by far the best method to treat a heart attack patient if they present within 4-8 hours.
Upon effective re-vascularisation, the heart attack patient should get stable, and be able to get on his/her feet within a day or two, and be discharge within a week.

Just to reiterate, heart attacks kills. TIME IS MUSCLE. If you have significant chest pain, and you are in the heart attack risk group ( age 40 and above, smoke, hypertension, diabetes, high cholesterol, ), go see a doctor as soon as you can. An ECG would help to diagnose your condition. All other test can wait. If you have an ECG suggestive of a heart attack, go to the nearest medical center for treatment. TIME IS MUSCLE. The specialist there may offer you angioplasty, if you arrive within the time window ( 4-8 hours ), and they have the capability, or they may offer you IV thrombolytic therapy ( clot busters ). Rest is important. Of course, there will be the usual cardiac medications, aspirin, plavix, vaso-dilators, ACE-I, Also the advice of diet, not to smoke, lose weight, etc, etc. But these can all wait, till after blood flow is restored to the heart muscle.

That should be the standard of care nowadays.

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