Bypass surgery (CABG) is a mechanical solution for a complex bio-chemical issue of the human body known as atherosclerosis. The grafts are used to bypass coronary arteries are also susceptible to atherosclerosis, specially the venous grafts. If you want to prevent graft re-stenosis than a proper diet and exercise schedule with regular follow-up to cardiologist is required. 

In the case of venous grafts which tend to close after 8-10 years, the patient again develops symptoms of Angina or breathlessness and require a check angiogram.

REDO-bypass surgery can be executed safely in experienced hands and by using multiple arterial grafts (An-OPCAB total arterial bypass) the long term results are improved.

This valve replacement surgery is not a remedial surgery but a palliative one, we are replacing a diseased valve with an unnatural valve!

When It is a case of a mechanical valve there are chances of valve thrombosis (blood clotting) which is a disastrous complication and leads to impaired or damaged valve function that needs urgent medical attention. In Valve thrombosis patient may need an urgent REDO-surgery. To prevent valve thrombosis patient are kept on anticoagulants and the PT/INR should be maintained as per the doctor’s advise. A tissue valve tends to degenerate after 12-15 years and a REDO-surgery is needed if its function worsens.

The REDO-cardiac surgery does carries a relatively high risk as compared to first surgery. The major risk factors of REDO- surgery are:

1. REDO-sternotomy: The major risk of a REDO-surgery is a REDO- sternotomy, because the heart and major blood vessels are adhered to the sternum due to primary surgery and they are at risk of injury while doing a REDO-sternotomy
2. PERICARDIAL adhesions: Because of a previous operation the pericardium is adhered to the heart muscle & relieving those adhesions is necessary to perform REDO-surgery.
3. There are chances of frequent blood loss and transfusions and more 

There are also frequent chances of blood loss and transfusions and more ICU & hospital stay as compared to primary surgery.

Yes, a REDO surgery can be performed through the MICS approach, hence avoiding a REDO-sternotomy and its associated complications.