​Ultrafiltration therapy aids heart failure patients resistant to diuretic drugs

Taxi driver Soh Teow Cheng (left) listens as NHCS consultant cardiologist David Sim explains how a device used in Aquapheresis therapy works. Mr Soh has undergone the treatment and shed 12 litres of excess fluid. -- PHOTO: LIANHE ZAOBAO

TAXI driver Soh Teow Cheng shed 12 litres of excess fluid and 8.8kg in weight after undergoing a new therapy at the National Heart Centre Singapore (NHCS) - all in a matter of 48 hours.

Aquapheresis therapy uses a technique known as ultrafiltration, in which blood containing excess fluid is withdrawn and passed through a special filter called a hemofilter. After removing the excess salt and water, the filter returns the blood to the body.

NHCS is the first in the region to introduce this therapy - it was first used in the United States in 2002 - and six patients have benefited since October.

Mr Soh, 59, was diagnosed with cancer in 2003 and chemotherapy damaged his heart muscle.

Eight years later, he was admitted to hospital for congestive heart failure. His heart could not pump enough oxygen-rich blood for his body's needs.

When that happens, patients suffer from fluid overload, or a retention of water in the body. It is commonly caused by a disorder of the kidney, liver or heart, as in Mr Soh's case.

Fluid overload can occur in any part of the body but usually in the lungs, legs and abdominal area.

With Mr Soh, the swelling was in his abdomen, legs and feet. He also suffered symptoms such as breathlessness and weight gain.

He failed to respond to the conventional treatment of diuretic drugs, or 'water pills', that induce production of more urine. High doses of medication and a low salt, low fluid diet also did not help.

'I couldn't walk, and would feel breathless covering a distance of less than 10m. The swelling in my abdomen was so bad, I looked like I was 10 months pregnant,' said Mr Soh who underwent the new therapy last month.

The duration of treatment depends on the severity of a patient's condition but ranges from a minimum of eight hours to a maximum of 72.

The six male patients, averaging 60 years of age, underwent ultrafiltration as they suffer from diuretic resistance, which means their kidneys do not respond to diuretic drugs. This happens to about 20 to 30 per cent of heart failure patients.

Before ultrafiltration, such patients are given higher than usual doses of diuretic drugs.

But studies have shown that patients given higher doses tend to have worse outcomes, said Dr David Sim, a consultant cardiologist in NHCS' department of cardiology.

The treatment costs about $2,000 a session, before subsidies. The number of ultrafiltration sessions a patient needs depends on his condition.

'Even though the cost is high, it's offset by the fact that they generally have shorter lengths of stay in the hospital. Also, by preventing re-admissions and unscheduled visits to clinics, it would work out to balance the costs,' Dr Sim said.

The treatment is currently available as an inpatient service but the NHCS' long-term aim is to roll it out as an outpatient programme for patients who will need to return regularly for the therapy. This means they will not be re-admitted for heart failure, added Dr Sim.

Heart failure is a top cause of cardiac admissions here, with about 5,000 cases yearly. The NHCS handles about 1,000 such cases a year.

Fluid overload accounts for more than 90 per cent of hospitalisations by heart failure patients.

With the new treatment, the NHCS estimates that about 50 patients a year will benefit.

Said Mr Soh: 'I no longer suffer breathlessness, can walk so much better and continue to work as a taxi driver. I feel very healthy now.'