Coronary artery bypass: Route to a healthier life
Coronary artery bypass surgery has witnessed so much progress over the past few years that today surgery can even be performed on a beating heart or by remotely controlled instruments. K T P Radhika Jinoy gets to the ‘heart’ of the matter to find out more about new surgical procedures and their advantages over conventional methods.
Every year heart disease and stroke kill about 17.2 million people, which is more than the population of many European countries like The Netherlands and Hungary. Over 80 per cent of these deaths occur in low- and middle-income countries like India, where Coronary Artery Disease (CAD) has become one of the most common types of heart disease due to changing lifestyles. Studies show that the rates of CAD patients in India have doubled in the past three decades.
CAD occurs when the arteries that carry blood to the heart muscles get blocked due to the settling down of cholesterol or other fatty materials on their inner walls. This situation is called atherosclerosis, which narrows the artery after a period of time. This may also lead to blood clots in the arteries, which can completely block the flow of blood to the heart, rending it fatal. Coronary artery bypass is one of the most common surgeries today to combat such heart problems.
The history of coronary bypass surgery dates back to the 1960s. The first successful coronary artery bypass surgery was conducted at Albert Einstein College of Medicine, USA, under Dr Robert H Goetz. This surgery created a new path in the history of cardiology. Since then, several developments have taken place in procedures. Due to these enhancements, today, a bypass surgery can be performed on a beating heart or even through the minimally invasive method.
Although initial stages of coronary narrowing can be treated through lifestyle modifications, patients with severe blockage of the left main coronary artery or with a disease involving two or more coronary arteries, need a bypass surgery. Coronary artery bypass surgery, popularly known as bypass surgery, re-routes or bypasses blood around clogged arteries through new routes.
Typically, a bypass surgery is performed by opening the chest of a patient. The breast bone is cut and the heart’s beating is then stopped. A heart-lung bypass machine is attached to the major arteries, which takes over the circulation of blood and oxygen to the rest of the body. This machine keeps the patient alive during surgery. “Generally, before the surgery, the patient’s coronary angiography and echocardiography are investigated for seeing the clotting state of blood,” explains Dr Harbhajan Singh Rissam, director – Clinical Cardiac Sciences, Max Heart & Vascular Institute, New Delhi.
Depending on the number of bypasses required, the procedure can take two to eight hours. The success of grafting depends on various factors like age, lifestyle and health of the patients. In many cases, successful grafts last around 10-15 years.
On a beating heart
Recent advances in surgery and medical devices allow doctors to have less invasive options for coronary artery bypass surgery. Now, doctors can perform the surgery even without stopping the heart. This technique is called off-pump bypass surgery, which was developed to avoid the complications of cardiopulmonary bypass (heart-lung machine) during cardiac surgery. This surgery helps decrease the amount of blood transfusions done during the surgery. “In the beating heart surgery, the heart-lung machine is not used and the heart beat is slowed down using drugs. The area where the graft is to be sutured is made static using a device called Octopus,” says Dr Anil Kumar, consultant cardiologist, Bombay Hospital & Medical Research Centre, Mumbai. Another device – Starfish – is used to lift the heart during the surgery. While the rest of the heart keeps beating, the surgeons can connect the bypass grafts on the blocked arteries.
Off-pump bypass has several advantages. Surgery on a beating heart means that blood does not have to go through the heart-lung bypass machine. “This prevents damage to the blood caused by circulation through the pump in the machine. Due to this mode, the success rate is high and the complication rate is minimum,” informs Dr Rissam. This method will also reduce complications. “Off-pump surgery reduces the cost, time and complications usually encountered in a bypass surgery. Moreover, patients take less time to recover after being operated on through this procedure,” avers Dr Kumar.
Minimally invasive method
The minimally invasive direct coronary artery bypass or MIDCAB technique is a less invasive version of the bypass surgery.
The latest development in minimally invasive surgery (MIS) is the Totally Endoscopic Coronary Artery Bypass (TECAB) surgery, which is performed using a surgical robot as an assistant. The surgeon uses remotely controlled surgical instruments to perform the surgery. The MIDCAB approach is performed on a beating heart and some patients can even leave the hospital within 48 hours. “MIS avoids long and large cuts on the body, as it is performed with small incisions and using heart port and robotic techniques. Also, the patient remains under anaesthesia for less time,” states Dr Rissam.
Since the operation is performed only through these small holes, the patient does not undergo much surgical trauma and scarring is almost negligible. Agrees Dr Kumar, “The incisions are small and are on the lateral aspect of the chest. So, the usually appearing scar-after-surgery will be small and there will be less pain post-operation. MIS will also allow a quick recovery and avoid complications.”
Another pioneering advancement taking place in MIS is an innovative approach called hybrid procedure. This combines minimally invasive bypass surgery and stented angioplasty in one operation. Further, it combines minimally invasive coronary artery bypass surgery (TECAB or MIDCAB) with catheter-based coronary intervention (percutanueous transluminal coronary angioplasty or PTCA and stenting).
Into the future
Technological advancements continue in coronary artery bypass surgery. “Some futuristic trends include minimum trauma to the patient and the use of robotic instruments to cut down on time and cost of surgery,” says Dr Rissam.