KUALA LUMPUR, Malaysia A coronary artery bypass surgery is done to restore blood flow to the heart, but it is usually performed when the heart is stopped.

This is because the heart has to be opened for the surgery, so it needs to be still for the operation. The heart’s pumping action will instead be taken over by the heart-lung (cardiopulmonary bypass) machine, which adds oxygen to the blood.

Although the surgery is considered a common one, an open-heart surgery comes with risks of complications during or following the procedure. That is why until today, the medical community is still debating the safety of the procedure.

Among the complications of an open-heart bypass are heart attack, stroke, irregular heartbeat, lung or kidney failure, chest pain and fever, blood loss or blood clot, memory loss and difficulty breathing.


These risks of complications, however, can be reduced using a technique called ‘off-pump coronary artery bypass’ or ‘off-pump’, for short.

The off-pump is a technique used mainly in minimally invasive bypass surgery, where the surgery takes place without the use of a heart-lung machine.

Prof Dr Mohd Zamrin Dimon, a Consultant Cardiothoracic Surgeon at Universiti Teknologi MARA (UiTM) Private Specialist Centre (UPSC) in Sungai Buloh told Bernama that it was a technique widely-used around the world.

This technique does not require the use of the heart-lung machine. This means that while the body is under total anaesthesia, the patient’s heart keeps its function (is still beating) during surgery.

It is not that the conventional method isn’t good, it’s just that having a machine take over the heart’s function comes with a risk, especially if the patient is old or suffering from diabetes, high blood pressure, kidney or lung problems, said the surgeon, who is also the dean of UiTM’s Faculty of Medicine.

A heart attack typically occurs when there is a lack of blood supply to the heart muscles due to blockage in one or more of the coronary arteries.

The lack of oxygenated blood flow to the heart causes the heart muscles to die and if left untreated, can lead to heart failure and sudden death.


Ischaemic heart disease remains the primary cause of death in Malaysia from the year 2005 to 2016, according to findings by the Statistics Department that was last updated in Oct 2017.

An average of 20,000 Malaysians get heart attacks every year. Sadly, 25 percent of them are under 50 years old.

On post-operative complications, Dr Mohd Zamrin said the risk of stroke is one that is most often talked about with patients. Although the risk is only 1 to 2 percent in a bypass surgery, it is still considered high.

With the off-pump technique, the risk of stroke is reduced to around 0.2 to 0.5 percent and although it may cause patient’s blood pressure to become destabilised, it would still be under control.

The conventional method also comes with a high risk of the heart not resuming normal functions post-surgery because its function was taken over by the machine during the surgery. This often happens to patients with a weak heart or one that has not been functioning well, he explained.


The off-pump technique has been introduced in Malaysia since the year 2000. However, many surgeons still preferred the conventional technique, said Dr Mohd Zamrin.

Among the reasons given were that they were more comfortable performing surgery on a heart in a ‘rested’ state and that an off-pump bypass was a highly intricate surgery requiring high-level expertise.

At the same time, many also attested to the efficacy of the technique as well as to its post-operative benefits.

Off-pump surgeries save time because it takes around four hours to perform, compared with the on-pump technique which can take as long as eight hours. When the heart functions as usual during surgery, the patient will not need to take very long to recover because the heart never stopped beating in the first place.

The post-operative period is the most critical time because complications usually occur then. The faster a patient heals after surgery, the lesser chances of complications occurring, he said.

Dr Mohd Zamrin added that that technique also reduces surgery costs because the patient did not require the use of a heart-lung machine or longer hospital stay.


Surgeons who wish to perform the off-pump technique need to attend special training in addition to always learning new techniques from more experienced cardiothoracic surgeons.

As one of the earliest local surgeons to be trained in off-pump bypass surgery, Dr Mohd Zamrin has also been called to train other local surgeons in the technique.

I have been training other (cardiothoracic) surgeons in the off-pump technique since 2002 at UiTM and other hospitals. Even though I am skilled in both techniques (on-pump and off-pump), I choose to perform off-pump surgeries whenever possible because I believe that it would reduce the risks for patients, he said.

In addition to having mastery of the technique, he said, surgeons who wish to perform the off-pump also needed to be patient, calm and imperturbable as they would be performing surgery on a beating heart.

Mastering this technique would give surgeons an edge and make them more versatile, allowing them to provide a wider range of treatment options for patients. UPSC is among the hospitals that offer this (off-pump) option and I myself have performed this technique on over 1,000 patients, he said.



Apart from medication and angioplasty (balloon stent), bypass surgery and minimally invasive cardiac (bypass) surgery are among other most effective methods of treating cardiac diseases.

The conventional method of bypass surgery involves the surgeon making a cut of about 30cm in the chest and cutting through all or part of the breastbone (sternotomy) to perform the bypass.

Minimally invasive bypass surgery, meanwhile, allows the surgeon to perform heart surgery through only a small incision of about 8cm on the left side of the chest, in between the ribs. This kind of surgery can result in less pain and quicker recovery for many people.

To perform this surgery, a surgeon would first have to master the off-pump technique. This is a technique in which a bypass surgery is performed on a beating heart.

The conventional method, on the other hand, would require the heart to be stopped during the surgery and its functions taken over by a heart-lung machine.

A sternotomy would be performed to pry apart the breastbone to reveal the heart (thus called open-heart surgery). This procedure will result in a longer recovery time of about two months.

The minimally invasive option, meanwhile, reduces trauma, pain and other post-operative risks, as well as recovery time.

Source: NAM News Network