Coronary thrombosis is defined as the formation of a blood clot inside a blood vessel of the heart. This blood clot may then restrict blood flow within the heart, leading to heart tissue damage, or a myocardial infarction, also known as a heart attack. Coronary thrombosis is most commonly caused as a downstream effect of atherosclerosis, a buildup of cholesterol and fats in the artery walls. The smaller vessel diameter allows less blood to flow and facilitates progression to a myocardial infarction. Leading risk factors for coronary thrombosis are high LDL cholesterol, smoking, sedentary lifestyle, and hypertension. Signs and symptoms A coronary thrombus is asymptomatic until it causes significant obstruction, leading to various forms of angina or eventually a myocardial infarction. Common warning symptoms are crushing chest pain, shortness of breath, and upper body discomfort. Pathogenesis Coronary thrombosis and myocardial infarction are sometimes used as synonyms, although this is technically inaccurate as the thrombosis refers to the blocking of blood vessels with a thrombus, while myocardial infarction refers to heart tissue death due to the consequent loss of blood flow to the heart. Due to extensive collateral circulation, a coronary thrombus does not necessarily cause tissue death and may be asymptomatic. The formation of coronary thrombosis generally follows the same mechanism as other blood clots in the body, the coagulation cascade. Also applicable is the Virchow's triad of blood stasis, endothelial injury, and hypercoagulable state. Atherosclerosis contributes to coronary thrombosis formation by facilitating blood stasis as well as causing local endothelial injury. Due to the large number of cases of myocardial infarction leading to death and disease in the world, there has been extensive study towards the generation of clots specifically in the coronary arteries. Some areas of focus: Coronary thrombosis can be a complication associated with drug-eluting stents. These stents that are placed to open up narrowed arteries are often infused with medicine to prevent repeat stenosis. However, they may actually lead to an increased coronary thrombus formation due to increased tissue factor expression and delayed healing within the vessels. Furthermore, the downstream endothelium has been shown to be impaired, leading to an environment that favors formation of clots. Evidence remains inconclusive about whether these risks outweigh the benefit of a coronary arterial stent. Inflammation may play a causal role in coronary artery disease and subsequent myocardial infarction due to coronary thrombosis. Increased levels of inflammation may lead to