Keeping a damaged heart alive

Three months ago, Lim Jia Yang was hooked up to the extracorporeal membrane oxygenation machine, which took over the function of his heart while it recovered from an infection.
PHOTO: Keeping a damaged heart alive

Lim Jia Yang, who recently turned 13, still pinches himself today to make sure he is really here.

The teenager who had been healthy all his life and was a top student at his school in Johor Baru, escaped certain death three months ago.

What began as a mundane sore throat ended with him being barely kept alive as he was rushed to Singapore by ambulance for treatment.

Jia Yang's heart muscle had been attacked by the virus which caused his sore throat and, to save him, doctors at Gleneagles Hospital, led by thoracic and cardiovascular surgeon Su Jang Wen, hooked him up to a machine which took over the function of his heart while it recovered from the infection.

Today, Gleneagles Hospital and other hospitals in Singapore are saving more lives with the extracorporeal membrane oxygenation, or Ecmo, machine.

Like Jia Yang, some patients have acute myocarditis - the inflammation of the heart muscle due to a viral infection.

Other reasons to use the Ecmo include heart failure, cardiac arrest and cardiogenic shock, in which the heart is unable to pump as much blood as the body needs, following open-heart surgery or respiratory failure.

In the past two years, Gleneagles Hospital has seen the number of patients on Ecmo support increase by 20 per cent a year. On average, it now sees 10 to 15 such patients a year.

One reason the machine is being used more is the multidisciplinary team of experts set up in 2012 to support its use, said a hospital spokesman.

This has allowed the hospital to accept more cases from around the region, as well as in Singapore, said Dr Su.

KK Women's and Children's Hospital (KKH) is also reporting an increase in the number of patients needing Ecmo support, which is now about 10 a year.

The indications for the use of the Ecmo continue to expand, said Dr Chan Yoke Hwee, deputy chairman of the division of medicine and senior consultant in children's intensive care at KKH.

In fact, the hospital is expanding its Ecmo programme beyond its walls to improve the odds of survival for newborn babies and children who are critically ill with treatable cardiopulmonary conditions in other hospitals, said Dr Chan.

The hospital's Emergency Extracorporeal Life Support Response Service will provide Ecmo support to such patients, so the baby or child can be stabilised before he is taken to KKH for further care.

On average, about six to eight children are admitted to restructured hospitals every year for myocarditis and two or three will need Ecmo support, say doctors.

Myocarditis cannot be predicted and, in some cases, can be life-threatening. Ecmo is therefore important in providing the critical life support, which can improve the outcomes and lives of children with myocarditis, said Dr Jonathan Choo, a consultant with the cardiology service at KKH's department of paediatric subspecialties.

It may start with flu-like symptoms and develop into heart-rhythm disorders, such as a slow or very fast heart rate, said Associate Professor Quek Swee Chye, head of paediatric cardiology at National University Hospital.

Other children may have low blood pressure and look pale and lethargic, while some come in a near-collapse state like Jia Yang.

Barely kept alive

On March 12, Jia Yang, who had been feeling unwell for a few days, fainted after he said he was breathless.

Fortunately, he was already at the accident and emergency (A & E) department at Regency Specialist Hospital (RSH) in JB and was immediately transferred to its coronary care unit.

He was started on medication to maintain his blood pressure, which had plummeted.

A heart echocardiogram showed that his heart was contracting poorly, with an ejection fraction of 20 per cent (a normal heart function would show a reading of more than 55 per cent).

He was diagnosed with viral myocarditis. From then on, his condition deteriorated rapidly. His only chance was to go on Ecmo support. However, there was no such machine available in JB.

His doctors then contacted Dr Su in Singapore to help.

Dr Su was ready to travel with the machine, but things hit a snag when he was told he could not connect the Ecmo to Jia Yang at RSH due to "administrative reasons".

Dr Paul Ling, a cardiologist at RSH, quickly decided to rush the boy to Singapore.

Accompanied by medical personnel, Jia Yang left RSH at about 9.45pm, while Dr Su organised a sizeable medical team - including an anaesthetist, a heart-failure cardiologist, an intensivist, an infectious-disease physician, an emergency-medicine physician and perfusionists - to be on standby.

At about 11pm, Dr Su received a message from the team escorting Jia Yang that his blood pressure was extremely low despite being given the maximum support medications.

The ambulance team was delayed on the way to Singapore as Jia Yang's passport had expired and they needed time at the immigration to sort it out.

"I told them to start cardiopulmonary resuscitation (CPR) and bring the boy here alive," said Dr Su.

At 11.45pm, the ambulance arrived at the A & E department at Gleneagles Hospital.

When Dr Su opened the ambulance doors, the medical team was still performing CPR on Jia Yang.

His two aunts - Madam Tan Lay Lay, 49, and Madam Soo Emei, 54 - who had accompanied him, were terrified that they were going to lose him.

His aunts were in the ambulance because his parents' passports had also expired and they were delayed in coming here.

With his blood pressure at a low 60/40mmHg, the boy fell into a coma.

He was rushed to the resuscitation room and had the Ecmo machine attached to him by midnight.

At that point, his heart function was barely at 5 per cent.

That night, Jia Yang's heart stopped beating for a few hours, while the Ecmo did its work.

"The heart monitor showed a flat line, but he had regained consciousness and could gesticulate to us," said Dr Su.

It was two days later that things started looking up. Jia Yang's heart started to show signs of life again.

By the fourth day, Dr Su felt that Jia Yang's heart had recovered sufficiently and he was taken off the Ecmo.

His heart continued to improve till it was back to normal by the fifth day.

Although the survival rate of patients who have gone on Ecmo support at Gleneagles Hospital is more than 80 per cent, such miraculous recoveries are not a guarantee, said

Dr Su. Families must be prepared to take their loved ones off the support if brain death has occurred.

"It is an expensive treatment and we choose our patients very carefully. In Jia Yang's case, we decided to go ahead because he is so young and his physiological reserve is good," he said.

Jia Yang's hospital bill came to $150,000.

"We knew it would be expensive, but it was still money that had to be spent to give Jia Yang a chance. I am deeply grateful to have my son back," said Madam Tan Lee Peng, 51, a housewife.

Jia Yang's father, Mr Lim Chew Keat, 57, is a senior manager at a supermarket. The couple have another son aged 16.

Adults Get Myocarditis Too

Myocarditis is impossible to predict and parents should be on the lookout for a tired and lethargic child who is breathless because of a viral infection, said doctors.

It also affects adults and usually more men than women suffer from it.

The average age of a patient suffering from myocarditis is 42, said Associate Professor Lim Chong Hee, senior consultant at the department of cardiothoracic surgery and director of the heart and lung transplant programme at National Heart Centre Singapore (NHCS).

It usually occurs during or after a viral infection, which triggers the patient's immune system to attack the heart muscle, said Prof Lim.

Myocarditis can range from a mild form - in which a patient shows no symptoms - to a highly severe situation, such as a heart attack, heart failure or abnormal heart rhythm, he said.

Luckily, severe myocarditis is rare, making up just 5 per cent to 10 per cent of the 50 adult patients at the NHCS who need Ecmo support every year, said Prof Lim.

At the National University Heart Centre, Singapore, 107 patients have had Ecmo support in the past decade, of whom 15 had myocarditis.

Ecmo is an extreme form of support for patients with very advanced heart failure and survival rates can reach 70 per cent if the heart recovers successfully while on the machine, said Prof Lim.

How the Ecmo works

The extracorporeal membrane oxygenation (Ecmo) machine is made up of a pump and several tubes.

The pump acts like the heart, drawing blood through the tubes out of the patient, pumping the blood through a membrane oxygenator and then back into the patient. The membrane oxygenator acts like the lungs, adding oxygen and removing carbon dioxide from the blood.

In the machine's earlier years, bleeding was the main problem as heavy doses of blood-thinning medicine were needed to prevent the machine's circuits from clogging up, said Dr Kenneth Chan, a respiratory specialist at Respiratory Medical Associates at Gleneagles Medical Centre and Mount Elizabeth Novena Specialist Centre.

he other major problem was that the older pumps tend to cause the blood cells to break down. This led to anaemia or insufficient and damaged red blood cells, which would then clump together and block the circuits, as well as the blood vessels, said Dr Chan.

Again, technology improved and modern pumps have less of this effect.

Despite improved technology, there are still risks. Having large tubes in the legs or neck can cause blood to clot, which, in turn, leads to stroke, deep vein thrombosis and pulmonary embolism, said Dr Chan.

Infection can also occur when germs enter the body through the tubes and circuitry.

However, it is a life-saving technique which mimics the natural function of the heart and lungs. It support the patient, while allowing the organs to heal, said Dr Chan.

Veno-venous Ecmo supports only the lungs and is used for severe lung disorders when conventional breathing machines do not work.

Veno-arterial Ecmo supports both the lungs and the heart.

This is useful for reversible heart conditions, such as a massive heart attack and heart inflammation due to a viral illness, said Dr Chan.

wanching@sph.com.sg


This article was first published on June 26, 2014.
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