Every year, there are more than 30,000 hospital admissions for acute heart failure in the Netherlands. These patients are often seriously ill when they end up in hospital and there is only one type of treatment available: loop diuretics. In patients with heart failure, the function of the heart is impaired and, as a result, the kidneys retain a lot of fluid. By stimulating diuresis, they get rid of that fluid. 'In half of the patients with acute heart failure however, this medication does not work sufficiently, says cardiologist and principle investigator Jozine ter Maaten. 'Because they do not recover, many patients stay in hospital for a long time. Also, a great number of patients die within six months or are rehospitalised.' Ter Maaten is therefore conducting research to improve care for these patients.
Salt as indicator
'Previous research already showed that low amount of sodium in urine during treatment with loop diuretics is associated with a higher risk of death or rehospitalisation. So we wondered if we would look at the amount of sodium patients excrete, do we see how well the medication is working? And can we then use this to provide personalised and more effective treatment?'
Ter Maaten investigated a modified strategy of current treatment. She and her team investigated this in 310 patients at the UMCG who came in with acute heart failure. The study compared two groups of patients, one group receiving the standard dose of loop diuretics, and the other group a dose adjusted to the amount of sodium in the urine. With a simple test researchers looked at the amount of sodium in the urine at regular intervals, and if it was too low, they prescribed more loop diuretics. The researchers did this during the first 36 hours of hospitalisation.
The study showed that the patients whose doses of loop diuretics were adjusted according to the amount of salt in the urine, the excess fluid was removed quicker than the group that received standard doses of loop diuretics. As a result, patients recover better and are less likely to die during hospitalisation. The increase in dosage also proved to be safe. 'A higher dose of lisduretica creates a higher workload for the kidneys, but we saw no deterioration of kidney function in this study,' says Ter Maaten. 'This is a nice first step towards personalised care for acute heart failure.'
Test introduced immediately
In the UMCG, the new strategy was immediately introduced in the treatment of these patients. Ter Maaten advises other hospitals to do the same. In follow-up research Ter Maaten and her team together with US scientists investigate if patients treated with this new strategy return to hospital less often and die less often.
Research with Dekker grant
For this study, Jozine Ter Maaten received a Dekker grant from the Dutch Heart Foundation two and a half years ago. Recently, she also received a Veni grant to investigate the role of fluid and sodium in acute heart failure.