Can you drink alcohol if you had mitral valve repair open heart surgery... Will alcohol cause any damage to heart if had surgery in the past?

Alcohol. One small alcoholic beverage a couple of times a week is usually ok. Having said this, if you've already had a surgery on your heart you might want be conservative about what you eat and drink. .
Generally yes. Check with your doc, but in general, alcohol in moderation is ok after you are healed from your surgery.