A heart attack (also known as a myocardial infarction) is the death of heart muscle from the sudden blockage of a coronary artery by a blood clot. Heart attack is a leading killer of both men and women. A heart attack occurs when blood flow to a section of heart muscle becomes blocked. If the flow of blood isn't restored quickly, the section of heart muscle becomes damaged from lack of oxygen and begins to die. Heart attacks occur most often as a result of a condition called Coronary Artery Disease (CAD). 

Although many people think of heart disease as a man's problem, women can and do get heart disease. In fact, heart disease is the number one killer of women in United States.

Warning signs of a heart attack
The American Heart Association and other medical experts say the body likely will send one or more of these warning signals of a heart attack:

• Anxiety, nervousness and/or cold, sweaty skin.
• Chest discomfort with lightheadedness, fainting, sweating
• Feeling of impending doom.
• Feeling of pressure, tightness, burning, or heavy weight.
• Irregularity in heartbeat.
• Nausea or shortness of breath.
• Pain in the chest, upper abdomen, neck, jaw, or inside the arms or shoulders.
• Pain in the shoulders, neck or arms.
• Paleness or pallor
• Squeezing or pain in the center of the chest lasting more than a few minutes.

How to avoid having a heart attack
Talk to your family doctor about your specific risk factors for a heart attack and how to reduce your risk. Your doctor may tell you to do the following:

• Control your Blood Pressure if you have Hypertension
• Control your Blood sugar if you have Diabetes
• Eat a healthy diet
• Exercise at least 30 minutes
• Limit your alcohol intake
• Lose weight if you're overweight
• Quit Smoking

Causes of Heart Attack
The most common cause of heart attack by far is

• Atherosclerosis or hardening of the arteries: With advancing age, cholesterol and calcium are deposited gradually in the walls of the coronary arteries. These deposits are called plaques. The process is known as atherosclerosis, or hardening of the arteries.
• Diabetes: Heart problems are the leading cause of death among people with diabetes, especially in the case of adult-onset or Type II diabetes.
• Emotional Stress: Stress is considered a contributing risk factor for heart disease because little is known about its effects. The effects of emotional stress, behavior habits, and socioeconomic status on the risk of heart disease and heart attack have not been proven. 
• Family history: Members of certain families are constitutionally more prone to heart attacks. There may be chances of having heart attack to other member of family if someone else has this disease before. 
• Gender: Overall, men have a higher risk of heart attack than women. But the difference narrows after women reach menopause. After the age of 65, the risk of heart disease is about the same between the sexes when other risk factors are High blood pressure or Hypertension: High blood pressure increases your risk of heart disease, heart attack, and stroke. 
• High cholesterol Diet:  The cholesterol may cause a blood clot to begin to form. The plaque and the blood clot block the artery partially or completely. The more the artery is blocked, the greater the resulting damage to the heart.   
• Increasing age: Older age is a risk factor for heart disease. In fact, about 4 of every 5 deaths due to heart disease occur in people older than 65.
• Lack of exercise: Physical inactivity, lack of regular exercise, sedentary lifestyle. People who are not active have a greater risk of heart attack than do people who exercise regularly. Exercise burns calories, helps to control cholesterol levels and diabetes, and may lower blood pressure.
• Obesity, Overweight or Excess weight: Extra weight is thought to lead to increased total cholesterol levels, high blood pressure, and an increased risk of coronary artery disease. Obesity increases your chances of developing other risk factors for heart disease, especially high blood pressure, high blood cholesterol, and diabetes.
• Sex Hormones: Sex hormones appear to play a role in heart disease. Among women younger than 40, heart disease is rare. But between the ages 40 and 65, around the time when most women go through menopause, the chances that a woman will have a heart attack greatly increase.
• Smoking: Cigarette smoking or other tobacco use, including cigars and chewing tobacco. Most people know that cigarette and tobacco smoking increases your risk of lung cancer, but fewer realize that it also greatly increases your risk of heart disease and peripheral vascular disease

Other causes of having heart attack are as follows:

• Anaphylactic shock
• Arrhythmias
• Coronary thrombosis
• Electrocution
• Electrolyte imbalance
• Gout and high uric acid (probable).
• Hypoxia
• Respiratory failure
• Severe injury
• Shock
• Type-A personality (hard-driving, perfectionist)

Signs & Symptoms of Heart Attack
Heart attack symptoms vary widely. The symptoms you experience may be different from those experienced by a relative or neighbor. For instance, you may have only minor chest pain while someone else has excruciating pain. Many people have permanent heart damage or die because they don't get help immediately. It's important to know the symptoms of a heart attack

• Chest discomfort - pressure, squeezing, or pain
• Discomfort in the upper body - arms, shoulder, neck, back
• Nausea, vomiting, dizziness, lightheadedness, sweating
• Shortness of breath
• Narrowing or blockage of the coronary arteries

Coronary Artery Disease is the major reason people have heart attacks. Prevention is important: two-thirds of women who have a heart attack fail to make a full recovery. In addition, women often have different heart attack symptoms than do men.

• Abdominal pain or heartburn
• Lightheadedness or dizziness
• Nausea or vomiting
• Neck, jaw, shoulder, upper back or abdominal discomfort
• Shortness of breath
• Sweating
• Unusual or unexplained fatigue

The pain may radiate to the left shoulder and arm, right shoulder and arm or both, to the neck or lower jaw or directly to the back into the between the two shoulder blades. Sometimes, no pain may be felt in the chest but only in one of the sites of radiation, i.e., shoulder, arm, neck, jaw or even pit of the stomach. The patient may feel very anxious.

There is usually no pain when the person is at rest. An exercise like brisk walking, running, going uphill, climbing the stairs or doing physical work precipitates the pain if such exertion is undertaken soon after meals. Emotional outbursts, anger, fright, hurry or sexual activity may induce such pain.

Preventions of Heart Attack
You can do nothing about the factors of age, sex and heredity. You cannot help aging; you cannot help being a male if you are one; nor can you choose your parents. All these factors are unmodifiable. But you can certainly modify other factors to your advantage.

Treatment of Heart Attack
The primary goal of treatment is to quickly open the blocked artery and restore blood flow to the heart muscle, a process called reperfusion. Once the artery is open, damage to heart muscle ceases, and the patient becomes pain free.

General treatment measures include the following:

• Oxygen through a tube in the nose or face mask
• Nitroglycerin under the tongue
• Pain medicines (morphine or meperidine)
• Aspirin: Those with allergy to aspirin may be given clopidogrel (Plavix).

Other Treatment Options:

• Bypass Surgery: In this procedure, a piece of vein is taken from the leg, or a piece of an artery is taken from the chest or wrist, and then attached to the heart artery above and below the narrowed area, thus creating a bypass around the blockage.
• Coronary Angioplasty or Balloon Angioplasty: In this procedure, a fine tube, or catheter, is threaded through an artery into the narrowed heart vessel. The catheter has a tiny balloon at its tip which is inflated and deflated to open and stretch the artery. This is done to improve blood flow, after which the balloon and tube are removed. Coronary angioplasty is performed in a catheterization laboratory (cath lab), under sedation and a local anesthetic.
• Drugs: Taking an aspirin during a heart attack and each day following a heart attack can decrease the risk of dying from the condition by almost 25%. Blood clots primarily are composed of platelets (microscopic particles that circulate in the bloodstream) that stick to ruptured plaques and to each other.
• Stent: Stents are often inserted during angioplasty to help keep the artery open. A stent may also be used without angioplasty. Basically, a stent is a wire mesh tube that's permanently inserted into an artery to help keep it from closing up again. Even with a stent, however, an artery can re-close, requiring either another angioplasty or a bypass.