Unfortunately, meditation is very unlikely to help you. There are several factors which influence high cholesterol, include genetic variation in the cholesterol pathway, but also being overweight, lack of exercise, smoking, alcohol consumption, and consuming a diet high in cholesterol.
This list, obviously, gives you a whole lot of life style options for lowering your cholesterol. Regular daily exercise (30-60 minutes on most days of the week is critical), as is consuming a healthy, balanced diet that is low in foods with high amounts of cholesterol (such as red meat). In small quantities, alcohol can be beneficial for your cholesterol levels, but in higher amounts it has the opposite effect. Stop smoking as well can have a big effect.
On the other hand, meditation may produce a sense of well being and relaxation. This has been shown to have some minor benefits for blood pressure, but it does not have the same effect on the levels of chemicals like cholesterol in the blood stream.
Talk to your primary care doctor
about these thing. Sometimes it will be necessary, depending on your overall risk for heart disease, to start a medication to lower your cholesterol levels, especially if diet and exercise do not do the trick.