Coronary Artery Disease
Hypertension is a major modifiable risk factor for CAD. Normally, CAD takes years to develop, but hypertension accelerates the atherosclerotic process that causes CAD. Then, as CAD progresses, the resulting arterial narrowing worsens the hypertension.
Its Pathophysiology
In CAD, atherosclerotic plaques collect in the arteries. These deposits, which line the intimal layer, consist of cholesterol and lipids.
In a person with hypertension, the elevated blood pressure causes high shear stress,
speeding the atherosclerotic process. As a result, the artery’s endothelial lining is injured. Then, platelets begin to accumulate at the site of the damage, resulting in a denuding injury.
Alternatively, hypertension can result when CAD causes a non denuding injury. After the endothelium is damaged, low-density lipoproteins (LDLs) and growth factor from platelets stimulate smooth-muscle proliferation and arterial-wall thickening. Smooth-muscle cells proliferate, trapping lipids. Over time, the lipids calcify and irritate the endothelium, causing platelets to adhere and aggregate. Thrombin is generated, and fibrin and thrombi form.
With denuding and nondenuding injuries, the thickened walls of atherosclerotic arteries lose their elasticity. Thus, the heart must beat harder to pump blood through the restricted vessels, increasing blood pressure even more .
Tags:atherosclerotic plaques, blood pressure, cad, Coronary Artery Disease, endothelium, hypertension, low density lipoproteins, platelets, shear stress smooth muscle cells