What Causes a Heart Attack

Over time, plaque can build up along the course of an artery and narrow the channel through which blood flows. Plaque is made up of cholesterol buildup and eventually may calcify or harden, with calcium deposits. If the artery becomes too narrow, it cannot supply enough blood to the heart muscle when it becomes stressed. Just like arm muscles that begin to ache or hurt when heavy things are lifted, or legs that ache when you run too fast; the heart muscle will ache if it doesn't get adequate blood supply. This ache or pain is called angina. It is important to know that angina can manifest in many different ways and does not always need to be experienced as chest pain.

If the plaque ruptures, a small blood clot can form within the blood vessel, acting like a dam and acutely blocking the blood flow beyond the clot. When that part of the heart loses its blood supply completely, the muscle dies. This is called a heart attack, or an MI - a myocardial infarction (myo=muscle +cardial=heart; infarction=death due to lack of oxygenv

Cocaine use. This drug can cause the coronary arteries to go into enough spasm to cause a heart attack. Because of the irritant effect on the heart's electrical system, cocaine can also cause fatal heart rhythms.

Prinzmetal angina or coronary artery vasospasm. Coronary arteries can go into spasm and cause angina without a specific cause, this is known as Prinzmetal angina. There can be EKG changes associated with this situation, and the diagnosis is made by heart catheterization showing normal coronary arteries that go into spasm when challenged with a medication injected in the cath lab. Approximately 2% to 3% of patients with heart disease have coronary artery vasospasm.

Anomalous coronary artery. In their normal position, the coronary arteries lie on the surface of the heart. On occasion, in the course of a part, the artery can dive into the heart muscle itself. When the heart muscle contracts, it can temporarily kink the artery and cause angina. Again, diagnosis is made by heart catheterization.

Inadequate oxygenation. Just like any other muscle, heart muscle requires adequate oxygen supply for it to work. If there isn't adequate oxygen delivery, angina and heart attack can occur. There need to be enough red blood cells circulating in the body and enough lung function to deliver oxygen from the air, so that heart cells can be supplied with the nutrients that they need. Profound anemia from bleeding or failure of the body to make enough red blood cells can precipitate angina symptoms. Lack of oxygen in the bloodstream can occur due to a variety of causes including respiratory failure, carbon monoxide poisoning or cyanide poisoning

  

Heart Attack | Medicines to Treat Heart Attack

If you have had a heart attack, your doctor has probably prescribed medicines that you will need to take for a long time. These medicines:

• help improve blood flow to your heart
• prevent blood clotting
• reduce your risk of having more heart problems in the future.

Path to improved health

Below is information about medicines that are commonly prescribed to treat heart attack. This includes their benefits, risks, and side effects. If you have questions or concerns about the medicines you are taking, ask your doctor for more information.

ACE inhibitors

ACE inhibitors can help if your heart is not pumping blood well. This type of medicine improves blood flow by helping to dilate (open) your arteries. It also lowers your blood pressure.

If you have acute coronary syndrome (ACS), your doctor may want you to take an ACE inhibitor. One ACE inhibitor might be all the medicine you need. Or your doctor may prescribe one in combination with other medicines. These could include a diuretic or a beta blocker.

Side effects: ACE inhibitors don’t usually cause troublesome side effects. The most common side effect is a dry cough. More rare side effects include

• dizziness
• reduced appetite
• fatigue (feeling out of energy)
• problems with the kidneys
• an increase in the level of potassium in the blood.

Risks: Because ACE inhibitors can cause birth defects, pregnant women should not take this type of medicine.

In rare cases, ACE inhibitors can lead to a serious allergic reaction. This reaction can cause swelling in certain areas of the body. It is more common in black people and people who smoke. It can be life-threatening. You should get immediate medical attention if you experience swelling after taking an ACE inhibitor.

Aspirin

Your doctor may want you to take a low dose of aspirin each day. Aspirin helps keep your blood from forming clots. Blood clots can clog the arteries that carry blood and oxygen to the heart. Blockages in these arteries increase your risk of having a heart attack or stroke.

Side effects: Common side effects of aspirin include nausea and upset stomach. Some people feel nervous or have difficulty falling asleep when taking aspirin. Call your doctor if your symptoms are bothersome.

Risks: Aspirin can increase your risk of stomach ulcers. It can also cause bleeding in your stomach and intestines. Doctors prescribe a low dose of aspirin for people who have ACS. The dosage is usually between 81 and 162 mg per day. The low dose provides the same benefits as a higher dose. But there is less risk of internal bleeding.

Talk to your doctor about the risks and benefits of aspirin therapy. He or she will prescribe the aspirin dose that is right for you. They will tell you exactly how to take it.

Beta blockers

Beta blockers lower the heart rate and blood pressure. They help improve blood flow to the heart, reduce chest pain, and prevent more damage to the heart. Your doctor may want you to take a beta blocker alone. Or he or she may want you to take it in combination with other medicines. These could include a diuretic or an ACE inhibitor.

Side effects: The side effects of beta blockers tend to be mild. Common side effects include cold hands, fatigue, dizziness, and weakness. Less common side effects include shortness of breath, difficulty sleeping, depression, and decreased sex drive.

Risks: Beta blockers are not recommended for people who have asthma. This type of medicine can trigger severe asthma attacks.

Beta blockers may make it difficult for people with diabetes to recognize signs of low blood sugar. One of these signs is rapid heartbeat. If you have diabetes, your doctor will probably tell you to check your blood sugar often.

Stopping beta blockers abruptly increases the risk of heart problems. If you need to stop taking a beta blocker, it’s important to stop gradually. Follow your doctor’s instructions carefully.

Antiplatelets

Antiplatelet medicines help prevent blood clots. They don’t allow certain cells in the blood (called platelets) to clump together. This reduces the risk of blockages in the coronary arteries that can lead to heart attack and stroke. They are sometimes prescribed along with aspirin therapy.

Side effects: Some common side effects of antiplatelet medicines include:

• nausea
• upset stomach
• stomach pain
• diarrhea
• itching
• rash.

Talk to your doctor if you experience side effects while taking this medicine.

Risks: Because antiplatelet drugs prevent blood clotting, they can increase the risk of serious bleeding in some people.

Diuretics

Diuretics (water pills) help the body get rid of extra sodium (salt) and fluid. They reduce the amount of fluid flowing through your blood vessels. This lowers your blood pressure.

Diuretics are commonly prescribed to treat high blood pressure. They are sometimes used in combination with beta blockers and ACE inhibitors.

Side effects: Common side effects of diuretics include:

• increased urination
• increased thirst
• fatigue
• muscle cramps
• low blood pressure.

Less common side effects include increased blood sugar, increased irregular menstrual periods in women, and impotence in men.

Risks: People who take diuretics can have too much or too little potassium in their blood. This depends on the type of diuretic they take.

Statins

Statins are used to lower “bad” cholesterol (LDL) levels. They may also help increase “good” cholesterol (HDL) levels. Most people who take statins will take this type of medicine for the rest of their lives.

Side effects: Muscle pain is the most common side effect of statins. The pain can be mild or severe. Less common side effects include nausea, diarrhea, gas, and constipation. People who take statins may also get a rash. This side effect is more common when a statin is taken in combination with niacin. This is another medicine used to lower cholesterol levels.

You are at higher risk of having side effects from statins if you:

• are a woman
• are age 65 or older
• have liver or kidney disease
• have type 1 or type 2 diabetes
• take several types of medicine.

Some people may feel discouraged by the side effects caused by statins. However, the side effects are not usually life-threatening. Your doctor can help you find ways to manage them. If you are worried about side effects, talk to your doctor about the risks and benefits of taking statins.

Risks: In some people, statins can cause liver damage. Your doctor may want to have your liver function tested on a regular basis.

Anticoagulants (blood thinners)

Blood thinners don’t actually thin the blood. They decrease the ability of the blood to clot. This helps prevent clots from forming in the blood vessels. It also may prevent clots from becoming larger. Large clots can cause more serious problems.

Side Effects: The most significant side effect of blood thinners is bleeding. Your blood doesn’t clot as easily. If you cut or injure yourself, you’ll bleed more than normal. The risk of bleeding being a major event is low.

Blood thinners can cause interactions. These could be with some foods, prescription medicines, or over-the-counter supplements. Less serious side effects include:

• swelling at the injection site
• diarrhea, vomiting, or inability to eat
• fever
• heavier than normal menstrual periods or bleeding between periods.

Risks: Some people who take blood thinners are more at risk of having bleeding problems. These include people who:

• are older than 75
• take other blood-thinning medicines
• have high blood pressure
• have cancer
• have problems with their kidneys or liver.

Be sure to tell your doctor about any other medicines or supplements you take. Tell other health care providers that you are taking a blood thinner.

Things to consider

All medicines can cause side effects. They also can carry risks for certain people. Always tell your doctor about any medicines you take. Tell him or her about any side effects you are experiencing. Make sure they know your full medical history so they can prescribe the best medicine for you.