Why this is important A randomised controlled trial should be conducted to investigate whether the addition of low-dose dopamine to standard therapy leads to more clinically and cost effective decongestion in people admitted to hospital for treatment of decompensated heart failure. The study should aim to investigate the diuretic effect of dopamine as well as effects on renal function. One of the most common and difficult to manage problems arising during the initial treatment of people with acute heart failure is an inadequate response to intravenous diuretic therapy (that is, failure to relieve congestion), which is often associated with worsening renal function. This combination frequently leads to a prolonged inpatient stay and is associated with higher inpatient mortality rates and higher post-discharge mortality and re-admission rates. The best treatment for this combination of problems is unknown. However, theoretical and experimental evidence indicates that low-dose dopamine may improve renal blood flow, as well as enhance sodium and water excretion. Clinical trials have not yet resolved whether in some patients, the use of low-dose dopamine actually results in improved decongestion and shorter hospital stays. In people with acute heart failure and persistent congestion, does the addition of a thiazide diuretic to standard therapy lead to greater diuresis compared with adding placebo to standard therapy? Why this is important A randomised controlled trial should be conducted to investigate whether the addition of a thiazide diuretic to standard therapy leads to more clinically and cost effective decongestion in people admitted to hospital for treatment of decompensated heart failure. One of the most common and difficult to manage problems arising during the initial treatment of people with acute heart failure is an inadequate response to intravenous diuretic therapy. 