Use in adults (generally ≥50 years) presenting to the ED with acute decompensated heart failure of <7 days duration, after initial stabilisation, when deciding between discharge, short-stay unit or inpatient admission.

The score was derived in the RAD-1 study, a prospective cohort of 559 ED visits for acute heart failure across six Canadian teaching hospitals. Ten bedside variables predicted a composite outcome of 30-day all-cause mortality plus serious events within 14 days. Overall, 11.6% of patients had a serious adverse event, and observed risk increased from about 3% at score 0 to nearly 90% at the highest scores.

The RAD-2 prospective validation enrolled 1,100 similar patients in the same ED network. The overall serious adverse event rate was 15.5%, with events including death within 30 days, admission to a monitored or critical care unit, endotracheal intubation or non-invasive ventilation, myocardial infarction, major cardiac procedures, new haemodialysis, or relapse requiring admission within 14 days.

Both studies excluded patients who were too unstable to be considered for discharge after 2–12 hours of ED care. Exclusion criteria included resting SpO2 <85% on room air or baseline oxygen, heart rate ≥120/min, systolic BP <85 mm Hg, confusion or dementia, ongoing ischaemic chest pain or acute ST-elevation MI, terminal illness with expected death within weeks, chronic haemodialysis, and residence in a nursing home or chronic care facility. The scale has not been validated in children or in non-ED settings.

In RAD-2, using an OHFRS threshold >1 increased sensitivity for serious adverse events into the low- to mid-90% range but increased admission rates. Subsequent reviews and a 2022 ACEP clinical policy recommend using the OHFRS mainly to identify patients at higher risk who should not be discharged, rather than as a stand-alone rule to define a very low-risk discharge group.

Because all major cohorts were from large Canadian tertiary EDs, calibration and admission thresholds may differ in Australian and other health systems. Use the score alongside clinical assessment, patient preferences and local heart failure pathways.

Ottawa Heart Failure Risk Scale (OHFRS) for ED disposition in acute heart failure.