High attitudes may produce hypoxemia through

The left ventricle is responsible for pumping oxygenated blood out of the heart and into systemic circulation, which requires generating enough pressure to overcome the resistance of the systemic blood vessels. Therefore, the left ventricle has thicker and more muscular walls than the right ventricle and can generate higher pressures during contraction. In contrast, the right ventricle pumps deoxygenated blood to the lungs, which have lower resistance compared to the systemic circulation, and therefore do not need to generate as high pressures.

Modifiable risk factors for coronary artery disease (CAD) are those that can be changed or controlled to reduce the risk of developing CAD. These include high blood pressure, high cholesterol levels, smoking, physical inactivity, unhealthy diet, and obesity. High HDL (high-density lipoprotein) is actually a desirable factor, as it is known as the "good cholesterol" and helps to remove excess cholesterol from the body. Orthostatic hypotension, or a drop in blood pressure upon standing, is not considered a modifiable risk factor for CAD.