What would be natural ways to cleanse arteries of plaque build up or potential blockages?

It's no mystery!: Balanced diet, good physical condition, exercise, normal body weight (including weight loss if you are overweight) -- and espeically no smoking -- can reduce plaque and lower risk of blockage, but may take months or years. Most people are unsuccessful in the necessary lifestyle changes. Drugs (e.g. a statin and BP meds if BP is high) often are more effective in lowering risk and prolonging life.