Prime Minister Nawaz Sharif recently underwent ‘open heart’ surgery and ‘bypasses’ in a ‘Harley Street’ clinic in London. What exactly went on during that surgery was not discussed in public. However, mention in passing was made of four bypasses. Without dwelling on what surgery the PM went through, the latest information is that he is recovering well from it and has returned to his London home from the clinic.

Heart problems are a major cause of illness and death. The exact heart illness, however, can vary from one age and socio-economic group to another. In young children, the commonest forms of heart disease are different abnormalities that children are born with. Some are immediately fatal and some can be treated to prolong life and even restore a relatively normal life to some of these children.

In teenagers and people in their early twenties a major heart problem is valve damage from Rheumatic Fever or what is sometimes thought of as ‘growing pains’. This is a relatively mild form of generalised pain in the joints and fever that is usually self-limiting except in its extreme form. However, this disease can cause damage to inside lining of the heart especially valves inside the heart. These valves then slowly get worse in time producing serious life threatening situations that could initially only be treated by some form of surgery.

The third category of heart disease includes degenerative changes in heart valves as well as blockages in the heart arteries. Blockages in heart arteries occur in older people and are perhaps related to an improving socio-economic status. Well to do people that can afford a rich diet often develop heart artery blockages that can then lead to heart attacks. Today blockages of heart arteries constitute one of the major causes of death among adults especially in advanced countries where life expectancy has increased during the last century along with an improved standard of living.

As medicine hit the twentieth century, major improvements in diagnosis and treatment started to occur. It was surgery that really developed first during the early part of the twentieth century. Four developments provided an impetus that allowed surgeons to perform operations for many different problems. These were the discovery and use of anaesthesia, antisepsis and control of surgical infections, discovery of blood groups and blood banking leading to safe transfusion of blood, and investigations like X-Rays.

As surgical skills improved overall, surgeons started thinking about operating on the heart. First successful heart operation was the closure of a stab wound of the heart in 1896 by Ludwig Rehn in Vienna. The patient survived and lived for many more years. Many injuries to the heart were treated successfully during World War II with repairs of heart wounds accomplished quite often. But ‘planned’ treatment of diseases of the heart was still wanting and direct operation on the heart was not considered as a way of treating heart problems. Improved understanding of heart function stimulated interest in treating heart problems especially in children and young people.

Since it was not yet possible to stop the heart and open it up to fix problems, techniques were devised to treat heart problems without interrupting heart function. These operations were essentially ‘closed heart operations’. The first ‘successful’ attempt to treat a heart valve problem was done in 1925 in England by Sir Henry Souttar. He opened the chest and a put a finger into a beating heart and blindly opened up a heart valve obstruction. It took twenty years before this operation became popular and was used very often. When I started my house job in cardiac surgery at Mayo Hospital in 1971, this was the commonest heart operation we were doing to treat narrowing of the valve between the upper and the lower heart chamber (Mitral Valve). I left for further training in the US before open heart surgery started at Mayo Hospital.

From an historical perspective the most famous closed heart operation occurred in 1944 when Alfred Blalock created a connection between two blood vessels (Blalock-Taussig shunt) away from the heart to treat ‘blue babies’. This operation was for many years the mainstay of treating a particular congenital heart problem and is widely practiced in Pakistan even today. Taussig part of the shunt is named after a female cardiologist called Helen Bing Taussig. This operation is now called the Blalock-Thomas-Taussig shunt. Vivien Thomas was an African American lab assistant who helped Blalock develop and perform this operation and only recently was given equal credit for this procedure.

The era of ‘open heart’ surgery formally started in 1953 when John Gibbon used a ‘heart lung’ machine (pump oxygenator) he had developed to take over heart function and ‘bypass’ the blood away from the heart. He then actually opened up the heart and closed an abnormal connection between the two upper chambers of the heart (atrial septal defect). Once such machines came into general use all sorts of heart problems could now be treated through surgery.

Two new terms were now added to the lexicon of heart surgery. ‘Open heart surgery’ meaning that the heart is actually opened up to perform an operation and ‘heart bypass’ surgery meaning an operation where a heart lung machine is used to bypass blood around the heart allowing the heart to be operated on. The most famous ‘open heart’ operation was of course a total heart transplant from one human to another done first by Christian Barnard in South Africa in 1967.

Even in this relatively modern era of heart surgery treatment for blocked heart arteries had to wait for development of a technique to take pictures of the blockages inside the arteries. This was first done almost accidentally by a cardiologist called Mason Sones in the middle sixties. The procedure that came about is called ‘coronary angiography’ and delineates blockages in heart arteries so they can be treated if necessary.

The first artery bypass operations were done in the late sixties. The heart arteries are called ‘coronary arteries’ and the operation is usually called ‘coronary artery bypass grafting’ (CABG). Initially a vein was removed from the leg and used to bypass (literally) the blockage in the heart artery. Now the artery running inside the chest wall called the left internal mammary artery or the left internal thoracic artery (LIMA/LITA) is used quite often. Today the CABG operation is probably the most often performed operation in much of the world possibly even including Pakistan.

Finally, many blocked arteries in the heart can now be opened up using catheters without approaching the heart from the outside. ‘Stents’ are placed inside the arteries to keep them open. Such procedures are not heart operations and are performed not by heart surgeons but medical heart doctors called cardiologists. These procedures are technically called Percutaneous Catheter Interventions (PCI). As technology and experience has evolved, even heart valve implantation and heart valve repairs are also being done through catheter (non-surgical) techniques.

As far as the PM is concerned, based on information available he most likely had at least a CABG to four heart arteries done using a heart lung machine to ‘bypass’ the heart.