Myocardial infarction ppt

Title: Myocardial Infarction 1 Myocardial Infarction • Zohair Y. J. Al-Hariri • King Khalid University Hospital • King Saud University • Riyadh, Saudi Arabia 2 What is MI? • Myocardial infarction is the death of part of the heart muscle due to its sudden loss of blood supply. • Death of the heart muscle often causes chest pain and electrical instability of the heart muscle tissue. • Approximately one million Americans suffer a heart attack annually. • Approximately 90 to 95 of heart attack victims who reach the hospital survive. 3 What causes MI? • A MI is caused by the formation of a blood clot on a cholesterol plaque. • Cholesterol plaque is the formation of a hard, thick substance within the artery walls which is caused by deposits of cholesterol in the artery walls • During exercise or excitement, the narrowed coronary arteries cannot increase the blood supply to meet the increased oxygen demand of the heart muscle. • Occasionally the surface of the cholesterol plaque in the artery may rupture, then completely occludes blood flow in the vessel and results in a heart attack. 4 What causes MI?(cont.) • Irreversible risk factors • Age • Gender • Family history • Potentially reversible risk factors • Hyperlipidaemia • Smoking • Hypertension • Other factors 5 What are the symptoms of MI? • Chest pain or pressure is a common symptom of MI. • Cardiac chest pain is often vague. • MI frequently occur from 400 A.M. to 1000 A.M. • Interestingly, MI do not usually happen during ex...

The patient’s history is critical in diagnosing myocardial infarction (MI) and sometimes may provide the only clues that lead to the diagnosis in the initial phases of the patient presentation. Patients with typical acute MI usually present with chest pain andmay have prodromal symptoms of fatigue, chest discomfort, or malaise in the days preceding the event; alternatively, typical ST-elevation MI (STEMI) may occur suddenly without warning. The typical chest pain of acute MI usually is intense and unremitting for 30-60 minutes. It is retrosternal and often radiates up to the neck, shoulder, and jaws, and down to the left arm. The chest pain is usually described as a substernal pressure sensation that is also perceived as squeezing, aching, burning, or even sharp. In some patients, the symptom is epigastric, with a feeling of indigestion or of fullness and gas. In some cases, patients do not recognize the chest pain, have an unusually high pain threshold, or have a disorder that impairs pain perception and results in a defective anginal warning system (eg, diabetes mellitus). In addition, some patients may have an altered mental status caused by medications or impaired cerebral perfusion. Elderly patients with preexisting altered mental status or dementia may have no recollection of recent symptoms and may have no complaints whatsoever. MI occurs most often in the early morning hours. Mechanisms that may explain this circadian variation include the morning increase in sympa...

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A heart attack (medically known as a myocardial infarction) is a deadly medical emergency where your heart muscle begins to die because it isn’t getting enough blood flow. A blockage in the arteries that supply blood to your heart usually causes this. If a healthcare provider doesn’t restore blood flow quickly, a heart attack can cause permanent heart damage and death. Overview A blocked coronary artery prevents blood from reaching your heart muscle and causes a heart attack. What is a heart attack? A myocardial infarction (commonly called a heart attack) is an extremely dangerous condition that happens because of a lack of blood flow to your heart muscle. The lack of blood flow can occur because of many different factors but is usually related to a blockage in one or more of your heart’s arteries. Without blood flow, the affected heart muscle will begin to die. If blood flow isn’t restored quickly, a heart attack can cause permanent heart damage and death. A heart attack is a life-threatening emergency. If you suspect you or someone you’re with is having a heart attack, call 911 (or your local emergency services phone number). Time is critical in treating a heart attack, and a delay of even a few minutes can result in permanent heart damage or death. What does a heart attack feel like? When a heart attack happens, blood flow to a part of your heart stops or is far below normal, which causes injury or death to that part of your heart muscle. When a part of your heart can’t...