Keyhole vs open-heart bypass surgery: what is the difference?
Keyhole (minimally invasive, MICS) bypass surgery is performed through a 3 to 7 centimetre incision between the ribs without dividing the breastbone, while traditional open-heart bypass uses a larger incision and splits the breastbone. The keyhole approach generally means less pain, a shorter hospital stay and faster recovery for suitable patients.
What is bypass surgery?
Heart bypass surgery, or coronary artery bypass grafting (CABG), treats coronary artery disease by rerouting blood around blocked arteries using a healthy blood vessel from elsewhere in the body. It can be performed either as a traditional open operation or, in suitable patients, through a keyhole approach. You can read the full overview on the heart bypass surgery page.
How does the incision differ?
In traditional open-heart bypass, the surgeon makes a 20 to 25 centimetre incision down the centre of the chest and divides the breastbone (a sternotomy) to reach the heart. In keyhole (MICS) bypass, the operation is carried out through a 3 to 7 centimetre incision between the ribs, and the breastbone is left intact.
Which has a shorter hospital stay and recovery?
Because the breastbone is not divided in the keyhole approach, recovery is generally quicker. Most keyhole bypass patients are discharged within 3 to 5 days, compared with 7 to 10 days typical after open surgery, and many return to normal daily activity in about two weeks. Recovery still varies from patient to patient.
Is keyhole bypass suitable for everyone?
No. The keyhole approach is not suitable for every patient. Whether it can be used depends on your coronary anatomy, the number and position of the blockages, and your overall health. Traditional open bypass remains an important and appropriate option in many cases. The right approach is decided together with your cardiologist after reviewing your angiogram and other investigations.
Does the surgical result differ?
The goal of both approaches is the same: to bypass the blocked coronary arteries and restore blood flow to the heart muscle. The keyhole approach aims to achieve this while reducing the trauma of accessing the heart. Suitability, safety and the expected result should always be discussed individually with your surgeon.
Written and reviewed by Prof. Dr. Shahrul Amry Hashim, Consultant Cardiothoracic Surgeon, KPJ Damansara Specialist Hospital 2. Last reviewed: September 2026.
Not sure which approach is right for you?
Prof. Shahrul can review your angiogram and advise whether keyhole (MICS) bypass is suitable in your case.