Question: How does cardiovascular and cardiorespiritory diseases affect humans?

Cardiovascular and cardiorespiratory diseases are the No.1 cause of death worldwide. Because they affect the whole body, not just the heart, veins, and arteries. This would be my short answer.

And here is a detailed explanation of what actually happens and how does cardiovascular diseases affect your body:
The whole cardiovascular system is the heart, arteries, veins, and capillaries. This system brings nutrients and oxygen-rich blood to all parts of the body. It also brings back to the heart the oxygen-poor blood so it can be oxygenated again. Cardiovascular disease can affect the body because they interfere with this oxygenation process. If the heart does not pump efficiently or if the arteries are narrow, then the capillaries may not get sufficient blood to do their job.
Here are the things that can happen if you have cardiovascular disease:
Heart Failure: This is the most common complication of heart disease. This occurs when the heart can no longer function correctly and either doesn’t fill properly between beats, or the muscles are weak and can’t pump properly.
Heart attack: This happens when a clot in the coronary artery blocks the blood flow, damaging the heart muscle or even destroying part of it.
Stroke: A stroke is caused by the brain not getting enough blood. Brain tissue starts to die just moments after a stroke.
Aneurysm: This can happen anywhere in your body. An aneurysm is a bulge in the artery wall. If it breaks, you can suffer from internal bleeding. Sometimes a clot in the aneurysm will dislodge and block an artery someplace else.
Peripheral artery disease (PAD): This is a condition where your extremities are not getting enough oxygen. The main symptom is leg pain when walking.
Cardiac arrest: This is a sudden loss of function in the heart, breathing, and consciousness. When this happens, the blood stops flowing.

Therefore my primary goal in my research is to understand the mechanism of cardiovascular and cardiorespiratory diseases so that I can develop efficient treatments that would benefit all of us.