[2018] Measure serum sodium and potassium and assess renal function before Chronic Heart Failure Treating Heart Failure NICE 2018. All rights reserved. Subject to Notice of rights. ISBN: 978-1-4731-3093-7 and after starting an MRA and after each dose increment.[2018] Measure blood pressure before and after each dose increment of an MRA. Follow the recommendations on measuring blood pressure, including measurement in people with symptoms of postural hypotension, in the NICE guideline on hypertension in adults. [2018] Once the target, or maximum tolerated, dose of an MRA is reached, monitor treatment monthly for 3 months and then at least every 6 months, and at any time the person becomes acutely unwell. [2018] Relative values of different outcomes The committee considered the following outcomes to be critical for this review: all-cause mortality, quality of life, and all-cause hospitalisation. Data on all-cause mortality and hospitalisation were considered preferable to data limited to heart-failure related mortality and hospitalisations, as such data take into account the broader unintended consequences of the interventions (for example, an increase in mortality or hospitalisations due to adverse events). Improvement of NYHA class and specified adverse events (hyperkalaemia, renal function, hypotension, and gynaecomastia) were also considered to be important for decision-making. Evidence was identified for all outcomes except for quality of life. The evidence for eplerenone and spironolactone was analysed together for all outcomes except for gynaecomastia, where the 2 interventions were analysed separately due to gynaecomastia being a common adverse effect of spironolactone but an uncommon effect of eplerenone. 