A heart attack is one of the dentures illnesses in all over the world. It occurs when part of the heart muscle is damaged or dies this happen because it isn't receiving oxygen.

Each year, more than a million persons in the U.S. have a heart attack and about half (515,000) of them die. About one-half of those who die do so within 1 hour of the start of symptoms and before reaching the hospital.

Causes

Cholesterol is one of the main causes of heart attack. Actually cholesterol plaques cause hardening of the arterial walls and narrowing of the inner channel (lumen) of the artery. Arteries that are narrowed by atherosclerosis cannot deliver enough blood to maintain normal function of the parts of the body they supply. For example, atherosclerosis of the arteries in the legs causes reduced blood flow to the legs. Common causes are :-

A diet high in cholesterol combined with smoking and lack of exercise can accelerate this process.

As these plaques grow, they begin to impede the flow of blood.

The growing plaque is like a firm shell with a soft inner core containing cholesterol.

As blood hits a plaque during each heartbeat, the plaque may crack open and expose the inner cholesterol.

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.

Symptoms

Chest pain behind the breastbone is a major symptom of heart attack, but in many cases the pain may be subtle or even completely absent due to this sign it is also called a "silent heart attack". This illness occurs mainly in the elder person and those with diabetes. Often, the pain radiates from your chest to your arms or shoulder; neck, teeth, or jaw; abdomen or back. Sometimes, the pain is only felt in one these other location. Common heart attack symptoms and warning signs may include :-

Chest discomfort.

Upper body pain.

Stomach pain.

Shortness of breath.

Anxiety.

Lightheadedness.

Sweating.

Nausea and vomiting

Treatment

The objective of thrombolytic (lysing the thrombus) therapy in acute myocardial infarction is to lyse (dissolve) the coronary thrombus (clot) and allow oxygenated blood to reach the heart muscle as quickly as possible. The goal is that intervention early in the course of infarction will limit infarct size, preserve left ventricular function, prevent pump failure and ultimately, prevent death.

If the ECG recorded during chest pain shows a change called "ST-segment elevation," thrombolytic therapy (blood-thinning drugs) may be started within 12 hours of when chest pain began.