**4. Risk factors**

Atherosclerotic risk factors are also the most common risk factors for MI. These risk factors are old age, obesity, smoking, hypertension, hypercholesterolemia more precisely hyperlipoproteinemia particularly high low density lipoprotein (LDL) and low high density lipoprotein (HDL), diabetes mellitus [20–23].

Furthermore, intense exertion, especially if the exertion is unusually more intense as compared to the usual performance, and emotional stress are other risk factors. Recent studies established that quantitatively, the duration of strenuous exercise and following recovery is associated with 6-fold higher MI rate in comparison to the more comfortable time frames for people who are physically more fit. For individuals with poor physical health, the rate differential is over 35-fold higher. Since the increased arterial pulse pressure results in stretching and relaxation of arterial vasculature with each heart beat thereby increasing the mechanical stress on atheromas, hence it significantly enhances the susceptibility of plaque ruptures [16, 24].

Increased spasm/contraction of coronary artery in association with cocaine abuse can also precipitate MI [25–29]. Gender is also another risk factor and male individuals are more prone to suffer from MI [30, 31].
