Ischemia occurs when plaque hardens and forms a clot in the arteries. As a result, the blood flow through the arteries is reduced. The plaque itself is made up of metabolic waste products formed through an ischemic cascade. In the case of cardiac ischemia, the blood flow to the heart is decreased thus leading to myocardial infarction.
Cardiac Ischemia can be caused by many things such as an unheathy lifestyle (i.e. smoking and obesity). Proir to Ischemia causing a heart attack, patients may have symptoms such as swelling in the limbs and fatique but can often show no symptoms until a myocardial infarction occurs.  This is also known as Silent Ischemia.
- ↑ 'Pathophysiologic cascades in ischemic stroke' Int J Stroke. 2012 Jul; 7(5): 378–385
- ↑ http://www.webmd.com
- ↑ https://www.healthline.com/health/ischemic-cardiomyopathy#symptoms2
- ↑ http://www.heart.org/HEARTORG/Conditions/HeartAttack/TreatmentofaHeartAttack/Silent-Ischemia-and-Ischemic-Heart-Disease_UCM_434092_Article.jsp#.We9ODWhSzIU