Minimally Invasive Bypass Surgery (MICAS)

Introduction:

Pathology:

The Coronary Arteries can develop blockages. These blockages are called Atherosclerotic Plaques as they develop by a process called Atherosclerosis. Atherosclerosis is the process through which Cholesterol & Calcium is deposited inside the arteries.

Complications:

Over a period of time, the blockages increase in size reducing blood flow to the heart muscles. 

• During physical activity or emotional stress, the heart has to pump more blood into the body. The reduced blood flow due to blockages causes a demand supply mismatch to the heart muscles. This leads to Chest Pain (Angina on Exertion).
• The plaque may crack or rupture forming a blood clot which can get trapped in blockages completely stoping flow of blood through the artery leading to injury or death of part of heart muscle causing a Heart Attack (Mycardial Infraction).

The usual investigations needed to diagnose and plan treatment for Coronary Artery Disease are ECG, Stress Test, 2D Echo & Coronary Angiography. The options available to manage significant blockages in Coronary Arteries are Angioplasty (PTCA/PCI) and Coronary Artery Bypass Graft (CABG) Surgery. 

Treatment:

Coronary Artery Bypass Graft (CABG) Surgery is a procedure in which a healthy blood vessel (artery or vein) is harvested from other location of the patient & used to form a detour (bypass) around a blockage in a coronary artery. The original blockage in the Coronary Artery is left untouched. The Graft now provides adequate blood supply to the heart muscle while bypassing the blockage and corrects the demand supply mismatch. Hence CABG eliminates the risk of a Heart Attack. Globally, Coronary Artery Bypass Grafting (CABG) is by far the most frequently performed surgical procedure.

• Minimally Invasive CABG

A small incision is made through the rib cage to access the heart. The procedure requires special instruments and techniques. This approach has its own limitations and is not applicable in all cases. 

Minimally Invasive Bypass Surgery (MICAS)

With advance in technology, Surgeons can now perform Cardiac Surgery through smaller incisions of 2 to 3 inches between the ribs and/or sternum. Specialized equipment has to be installed in the operation theatre to perform Minimally Invasive Bypass Surgery. The surgeon and his team have to be trained to use this equipment and perform the surgical procedure.

The Surgeon may recommend Minimally Invasive Bypass Surgery after medical investigations confirm that risk associated with the procedure is within limits. The criteria includes:

1. Physical examination and attributes of Patient
2. Detailed medical history of Patient
3. Results of specific investigations 

All patients do not meet criteria required for Minimally Invasive Cardiac Surgery (MICAS). In rare cases, if the Surgeon feels that it is not safe to continue with planned minimal invasive approach, they might convert the procedure to Conventional Open Heart Surgery. 

Though the approach in Minimally Invasive and Convention Open Heart Bypass Surgery are different, the goals are the same. Minimally Invasive Bypass Surgery offers same results as Conventional Open Heart Bypass Surgery with many added benefits. 

Salient Features of Minimally Invasive Coronary Artery Surgery (MICAS)

• The Grafts used to bypass the blocked Coronary Arteries are harvested from the patients own body. The patients body responds very differently to the metallic stent used in Angioplasty, which it treats as a foreign body. Hence, Grafts are fully compatible as compared to a metallic stent. As a result, the Graft survives much longer than a Stent. In most CABG’s, the Graft is observed performing very well even after 15 years of surgery.
• In Minimally Invasive CABG, all the blockages in Multi Vessel Coronary Artery Disease can be corrected at the same instance. Hence, repeated interventions are not required.
• After Minimally Invasive CABG Surgery, the patient spends significantly lesser time in the hospital due to smaller incision. 
• The patient experiences significantly lesser pain after Minimally Invasive CABG Surgery.
• The patient has lower loss of blood during Minimally Invasive CABG Surgery and hence requires lesser blood transfusion.
• The short term as well as long term quality of life improves significantly after Minimally Invasive CABG. Feedback from patients indicates their life being restored to what it was before the start of symptoms of heart disease.
• In Diabetic Patients, a study titled “Bypass Angioplasty Revascularization Investigation (BARI)” concluded that the risk of death (mortality) in cases with “Multi Vessel Coronary Artery Disease” was significantly greater in the first 5 years after Angioplasty as compared to CABG. Hence, Bypass Surgery is better suited for treatment of Coronary Artery Disease in Diabetic Patients.