Minimally invasive heart surgery refers to several approaches for bypassing critically blocked arteries. The minimally invasive procedures are less difficult and risky than conventional open heart surgery such as coronary artery bypass grafting, or CABG. The minimally invasive procedures restore healthy blood flow to the heart without having to stop the heart and put the patient on a heart-lung machine during surgery.

Currently, there are three types of these procedures:

• Minimally Invasive Direct Coronary Bypass (MIDCAB)
• Off-Pump Coronary Artery Bypass (OPCAB)
• Robotic Assisted Coronary Artery Bypass (RACAB)

Patients who have one these procedures instead of open heart surgery have a lower risk of complications associated with the heart-lung machine such as stroke, lung problems, kidney problems, and problems with mental clarity and memory. In addition to reduced complications, other benefits of minimally invasive heart surgery are faster recovery and reduced hospital costs.

MIDCAB: This procedure is for patients with blockage or blockages in the arteries on the front of the heart. (The left anterior descending (LAD) artery and its branches.) It allows the surgeon to perform bypass surgery without splitting the breastbone. A cut is still made on the patient's left chest to expose the heart, but unlike conventional open heart surgery, it is much smaller. After muscles in the area are pushed apart and a small part of the front of the rib (costal cartilage) is removed, the surgeon temporarily closes off the artery that lies underneath and frees its lower end. An opening is made in the pericardium, the covering of the heart. A device is attached to the heart to reduce its movement. Finally, the surgeon connects the artery below the blockage to the LAD artery or one of its branches. Once the other artery under the costal cartilage is re-opened, blood flow bypasses the blockage and feeds the heart. A heart-lung machine is not required.

This procedure offers the benefits of conventional open heart surgery but with less traumatic injury. The recovery may be closer to that experienced by angioplasty patients. Unfortunately, the procedure is limited to only a few patients who need only 1-2 bypasses.

OPCAB: During this procedure, the surgeon must cut open the chest and split the breastbone. A heart-lung machine, however, is not used. During the procedure, the surgeon makes a cut to open the patient's chest and expose the heart. An artery or vein will be taken from one of the patient's legs, and will be used to make the bypass. Like the MIDCAB procedure, a device is used to restrict movement of parts of the heart so that the surgeon can operate on it while it is still beating. The surgeon can repair four to five vessels on the beating heart during the same procedure.

The use of OPCAB has grown significantly because of its advantages over other procedures. Compared with patients undergoing conventional heart bypass surgery, those undergoing OPCAB require fewer blood transfusions, may have a decreased risk of stroke, have a shorter stay in the hospital after surgery, and may be able to return to normal activities more rapidly.

MIDCAB and OPCAB surgeries both take approximately 3 - 4 hours.

RACAB is the latest advance in heart surgery. Surgeons use a robot to perform the bypass. The breastbone does not need to be split open at all. Surgeons do not have direct contact with the patient. They perform the operation while watching a videoscreen. As the technology becomes more advanced, the surgeon may perform coronary bypass from a distant site (that is, from another room or another geographical location).

MIDCAB: Due to the limited size of the MIDCAB incision, only certain patients are eligible for the procedure:

1. Patients who have a blockage in one or two coronary arteries located on the front side of the heart, but are considered too high-risk for conventional bypass surgery or balloon angioplasty.

2. Patients who are otherwise healthy but have a blockage in one or two coronary arteries located on the front side of the heart.

In general, every patient with coronary artery disease is a candidate for OPCAB. However, for younger patients, for those who have small coronary arteries and need several bypasses, or those whose heart will not tolerate being manipulated during the procedure, it may be preferable to use the traditional CABG technique. Currently, the following patients with coronary artery disease are potential candidates for OPCAB:

1. Patients with poor heart function (very low ejection fraction).

2. Patients with severe lung disease (chronic obstructive pulmonary disease, COPD, and emphysema).

3. Patients with acute or chronic kidney disease.

4. Patients at high risk for stroke.

5. Patients with a calcified aorta.

Performing surgery on a beating heart (for both MIDCAB and OPCAB procedures) is technically more difficult than working on a heart that has been stopped with the help of the heart-lung machine. In addition, the stress on the heart during the procedure may lead to more heart muscle damage, lower blood pressure, irregular heart beat and potentially, brain injury if blood flow to the brain is reduced for too long during surgery. In some cases (usually less than 10%), it is necessary to convert to conventional CABG methods on an emergency basis.

MIDCAB and OPCAB patients typically spend one day in the surgical intensive care unit and then move to a regular surgery unit, where they receive cardiac rehabilitation. The average hospital stay is 3 days for MIDCAB patients and 5-7 days for OPCAB patients. In contrast, a hospital stay of 6-10 days is typical for conventional CABG patients.

Patients who have had MIDCAB have lower chest wound infection rates than patients who have undergone CABG or OPCAB. A smaller incision means less exposure and handling of tissue, which reduces the chance of infection.

MIDCAB patients recover more quickly than those who undergo CABG or OPCAB. Within 2 weeks, most MIDCAB patients can return to their normal activity level, compared with 2-3 months for patients who have had conventional surgery.

OPCAB patients have a recovery that in most respects is similar to that for CABG patients. Most are able to return to full activity, including work, 2-3 months after operation.