Abstract
AIMS: There is growing recognition of the burden and prognostic significance of WHF treated in the outpatient setting. However, there is currently a lack of prospective real-world data in this area of HF care. This study aims to analyse the natural history of outpatient WHF. METHODS AND RESULTS: This is a prospective, observational study of consecutive patients treated for WHF in our ambulatory HF clinic from August 2022 to March 2024. The diagnosis of WHF was made according to two definitions. The first required meeting strict pre-specified diagnostic criteria. The second included patients not meeting these diagnostic criteria but deemed to have WHF by a senior cardiologist. All patients required escalation in diuretic therapy (oral and/or intravenous) for inclusion. Clinical endpoints included outcomes from the presenting WHF episode and over the subsequent 3 months. Of the 234 patients treated for outpatient WHF, stabilisation was achieved in 78.6% (184) with 16.2% (38) requiring HF hospitalisation. A further 3.4% (8) experienced non-HF-related admissions, 2 (0.9%) patients died without hospitalisation and 2 (0.9%) patients requested follow up in other units for geographic ease. Bailout therapies (oral metolazone and/or IV loop diuretic) were used in 45.3% (106), and adverse clinical outcomes were significantly higher in this group than among those treated with oral loop diuretic only (35.8%, 38/106 and 9.4%, 12/128 respectively; odds ratio 7.24, P < 0.001). Of those who initially stabilised, 24.5% (45/184) had recurrent outpatient WHF during the subsequent 3-month period of follow-up, and 4.9% (9/184) were hospitalised for HF. CONCLUSIONS: Outpatient WHF was successfully treated in the majority of patients in the community. However, despite initial stabilisation, there is a persistent risk of recurrent deterioration. This may reflect challenges in defining stability clinically in HF patients. Biologic markers of stability and closer follow-up may help to address this challenge and improve outlook for this at-risk group.