What happens in a heart attack?
The most common presentation of someone who's had or having a heart attack is squeezing/crushing chest pain which is worse with exertion, shortness of breath, nausea and sweating. However, the vast majority of people with those symptoms who show up in the emergency department end up not having a heart attack. It could be indigestion, muscle strain, pneumonia, etc. Also, many heart attack patients don't have any symptoms that are remotely close to what is described in medical school as being typical. Thus, the first thing that happens in a heart attack is trying to figure out if it's a heart attack or not.
A heart attack (or myocardial infarction) is when there is insufficient blood supply to the heart. This can be caused most commonly by a clot that gets stuck in one of the vessels supplying the heart, or by narrowing of the vessel by cholesterol plaques. The cure for this is to either break up the clot (thrombolysis), use a flexible needle to snake into the blocked vessel and expand it open with an inflatable balloon (percutaneous coronary intervention), or open heart surgery with replacement of the blocked vessels with normal vessels from somewhere else in the body (coronary artery bypass graft).
This is how people get to those treatments.
The first health care providers to get to a patient are the paramedics. If there's chest pain, they pretty much always do a quick electrical scan of the heart, called an electrocardiogram, or ECG/EKG. If there's a pattern known as ST segment elevation, it's as emergency as emergency gets. These people need to get to a hospital for thrombolysis, or PCI, or CABG if PCI is not possible. Not all hospitals have PCI and CABG available but they all have thrombolysis medication. Generally, thrombolysis is tried first unless the patient can get to a PCI capable hospital fast enough. If thrombolysis doesn't work, patients are sent to a PCI and CABG ready facility.
But let's say the paramedics don't see any ST elevation on their ECG. The patient is then brought to the emerg where they're treated with a chest pain protocol which usually involves aspirin, oxygen, nitroglycerin and something for pain if the paramedics haven't already given it. In addition another ECG is done just in case the heart attack was missed. Again, if ST elevation is seen, get the clot buster/PCI going. The faster a heart attack is treated, the better off the patient is.
A set of blood work called a troponin is also drawn. This is a chemical in the blood that is released from damaged heart muscle. If it's positive, it usually means a heart attack has happened. However, the kind of heart attack you get with a positive troponin and a normal ECG is not treated with emergency thrombolysis/PCI/CABG, but the patient is admitted to the hospital for treatment and investigation, potentially leading to PCI or CABG in the days following admission. Troponins can take up to six hours to turn positive, so a rule of thumb is that anybody being investigated for a heart attack needs to have a second set of troponin drawn six hours after their symptoms were the worst. It's a big pain to wait and yes the emergency room is boring, but hey. Let's not mess around with yer ticker.
Chest xrays and additional bloodwork are also completed, just to make sure there isn't another disease that feels like a heart attack going on.
I can't count how many people I've seen who had chest pain that sounded just like a textbook heart attack, but had negative ECGs, negative bloodwork and negative chest xray. These people don't get kicked out the door with a clean bill of health. They get seen by a cardiologist sometime after they leave the ER for an examination and stress tests to make one hundred percent sure there isn't a heart problem. Just because you didn't have a heart attack doesn't mean you don't have heart disease.
The most common presentation of someone who's had or having a heart attack is squeezing/crushing chest pain which is worse with exertion, shortness of breath, nausea and sweating. However, the vast majority of people with those symptoms who show up in the emergency department end up not having a heart attack. It could be indigestion, muscle strain, pneumonia, etc. Also, many heart attack patients don't have any symptoms that are remotely close to what is described in medical school as being typical. Thus, the first thing that happens in a heart attack is trying to figure out if it's a heart attack or not.
A heart attack (or myocardial infarction) is when there is insufficient blood supply to the heart. This can be caused most commonly by a clot that gets stuck in one of the vessels supplying the heart, or by narrowing of the vessel by cholesterol plaques. The cure for this is to either break up the clot (thrombolysis), use a flexible needle to snake into the blocked vessel and expand it open with an inflatable balloon (percutaneous coronary intervention), or open heart surgery with replacement of the blocked vessels with normal vessels from somewhere else in the body (coronary artery bypass graft).
This is how people get to those treatments.
The first health care providers to get to a patient are the paramedics. If there's chest pain, they pretty much always do a quick electrical scan of the heart, called an electrocardiogram, or ECG/EKG. If there's a pattern known as ST segment elevation, it's as emergency as emergency gets. These people need to get to a hospital for thrombolysis, or PCI, or CABG if PCI is not possible. Not all hospitals have PCI and CABG available but they all have thrombolysis medication. Generally, thrombolysis is tried first unless the patient can get to a PCI capable hospital fast enough. If thrombolysis doesn't work, patients are sent to a PCI and CABG ready facility.
But let's say the paramedics don't see any ST elevation on their ECG. The patient is then brought to the emerg where they're treated with a chest pain protocol which usually involves aspirin, oxygen, nitroglycerin and something for pain if the paramedics haven't already given it. In addition another ECG is done just in case the heart attack was missed. Again, if ST elevation is seen, get the clot buster/PCI going. The faster a heart attack is treated, the better off the patient is.
A set of blood work called a troponin is also drawn. This is a chemical in the blood that is released from damaged heart muscle. If it's positive, it usually means a heart attack has happened. However, the kind of heart attack you get with a positive troponin and a normal ECG is not treated with emergency thrombolysis/PCI/CABG, but the patient is admitted to the hospital for treatment and investigation, potentially leading to PCI or CABG in the days following admission. Troponins can take up to six hours to turn positive, so a rule of thumb is that anybody being investigated for a heart attack needs to have a second set of troponin drawn six hours after their symptoms were the worst. It's a big pain to wait and yes the emergency room is boring, but hey. Let's not mess around with yer ticker.
Chest xrays and additional bloodwork are also completed, just to make sure there isn't another disease that feels like a heart attack going on.
I can't count how many people I've seen who had chest pain that sounded just like a textbook heart attack, but had negative ECGs, negative bloodwork and negative chest xray. These people don't get kicked out the door with a clean bill of health. They get seen by a cardiologist sometime after they leave the ER for an examination and stress tests to make one hundred percent sure there isn't a heart problem. Just because you didn't have a heart attack doesn't mean you don't have heart disease.
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