MYOCARDIAL INFRACTION BY HAWRA MAHDI

EPIDEMIOLOGY When MI is greater ?age &sex? Risk is greater with increasing age,after 60 yrs And more common in men than women,ratio 2:1 after 60 yrs What are major risk factors for MI? Systemic hypertension Smoking DM Elevated blood cholesterol

WHAT IS MI ? Myocardial infraction “refer to death of tissue (heart muscle)due to lack of blood supply. Definition A heart attack occurs when 1.the flow of blood to the heart is blocked due to a build-up of fat, cholesterol and other substances, which form a plaque in the arteries that feed the heart (coronary arteries). 2. The interrupted blood flow can damage or destroy part of the heart muscle.

HOW MI OCCUR ?

15% to 20% 30% to 40% 40% to 50%

THE SIZE OF INFARCTION DEPENDS ON WHAT ? The size of infarction depends on 1. Site of the thrombus: occlusion more proximal segment of coronary artery produce larger infarction involving full thickness of the myocardium, while thrombus of distal artery branches causes smaller infarcts. 2. Collateral circulations at time of occlusion: these collaterals limit the size of infarction.

WHAT ARE SIGNS& SYMPTOMS OF MI ?

THANK YOU