Rationale and Design of the DECONGEST (Diuretic Treatment in Acute Heart Failure With Volume Overload Guided by Serial Spot Urine Sodium Assessment) Study

Aims: To evaluate whether early-combination diuretic therapy guided by serial post-diuretic urine sodium concentration (UNa⁺) assessments in acute heart failure (AHF) facilitates safe and effective decongestion.

Methods: The Diuretic Treatment in Acute Heart Failure with Volume Overload Guided by Serial Spot Urine Sodium Assessment (DECONGEST) study is a pragmatic, 2-center, randomized, parallel-arm, open-label study aiming to enroll 104 patients with AHF and clinically evident fluid overload requiring treatment with intravenous loop diuretics. Patients are randomized to receive standard of care or a bundled approach comprising: (1) systematic post-diuretic UNa⁺ assessments until successful decongestion, defined as no remaining clinical signs of fluid overload with a post-diuretic UNa⁺ ≤ 80 mmol/L; (2) thrice-daily intravenous loop diuretic bolus therapy, with dosing according to estimated glomerular filtration rate; (3) upfront use of intravenous acetazolamide (500 mg once daily [OD]); and (4) full nephron blockade with high-dose oral chlorthalidone (100 mg OD) and intravenous canreonate (200 mg OD) for diuretic resistance, defined as persisting signs of fluid overload with a post-diuretic UNa⁺ ≤ 80 mmol/L. The primary endpoint of the DECONGEST study is a hierarchical composite of (1) survival at 30 days; (2) days alive and out of hospital or care facility up to 30 days; and (3) greater relative decrease in natriuretic peptide levels from baseline to day 30.

Conclusion: The DECONGEST study aims to determine whether an intensive diuretic regimen focused on early combination therapy, guided by serial post-diuretic UNa+ assessments, safely enhances decongestion, warranting further evaluation in a larger trial powered for clinical events.