The main causes of dizziness and cerebral insufficiency are as follows: 1. Heart failure, especially left heart failure, decreases the ejection of blood from the heart to the aorta, causing dizziness due to insufficient perfusion of various organ tissues, including the brain. 2. Heart valve disease, such as severe aortic stenosis, significantly increases the resistance to ejection of blood from the left ventricle to the aorta during systole, and decreases the amount of blood discharged from the heart causing cerebral insufficiency of blood supply. 3. Atherosclerosis caused by various reasons, such as hypertension, diabetes mellitus, hyperlipidemia patients. If atherosclerosis occurs, especially severe carotid atherosclerosis, causing severe carotid stenosis affecting the blood supply to the brain, dizziness may occur. 4. Severe cervical spondylosis, especially vertebral artery cervical spondylosis, can lead to compression of the vertebral artery, affecting the blood supply from the vertebral artery to the brain, resulting in dizziness due to insufficient blood supply to the brain.