Between 25% and 30% of patients hospitalized for acute heart failure (AHF) are readmitted within 90 days after discharge. Mostly due to persistent congestion on discharge. However, as the optimal evaluation of decongestion is not clearly defined, it is necessary to implement new tools to identify subclinical congestion to guide treatment.

Inclusion Criteria:

- Hospitalization of 24 hours or greater for decompensated heart failure defined as new-onset of symptoms or worsening of previous symptoms (including orthopnea, progression to FC III-IV, bendopnea or fatigue) or signs of volume overload.

and - Jugular venous distension, hepatojugular reflux, lower extremity edema or signs of pulmonary congestion.

and

• Chest X-ray with signs suggestive of pulmonary congestion. and
• Elevated ´pro-B-type natriuretic peptide (NT-proBNP) levels of 450 pg/mL, 900 pg/mL, and 1800 pg/mL for ages < 50 years, 50 to 75 years, and > 75 years, respectively, within 24 hours of admission (53,54).

and

- Sufficient ultrasound visualization to assess IVC and lungs.

Exclusion Criteria:

• Not willing to participate.
• Life expectancy of less than 6 months.
• Uninterpretable lung or inferior vena cava ultrasound.
• Transfer to another hospital before hospital discharge.
• SBP < 90 mm Hg.
• Chronic kidney disease (creatinine clearance <30 mL/min calculated with the MDRD equation or hemodialysis).
• Requirement for invasive or noninvasive ventilator support.
• Pregnancy.
• Low cardiac output syndrome/cardiogenic shock.
• Death during index hospitalization.
• Acute coronary syndrome, myocardial revascularization or heart valve replacement within the previous 3 months.
• Being on heart transplant waiting list.
• Cardiac resynchronization therapy device implanted within the previous 3 months.
• Severe tricuspid valve regurgitation.
• Heart failure secondary to causes amenable to invasive correction: cardiac surgery, percutaneous interventions or pacemaker implantation.
• Heart failure secondary to significant arrhythmias (advanced atrioventricular block or sinus arrest, sustained ventricular tachycardia or any sustained arrhythmia other than atrial fibrillation causing hemodynamic instability according to the discretion of the treating physician).
• Heart failure secondary to severe systemic infection
• Severe psychiatric illness
• Palliative care
• SARS-CoV-2 infection

CAVAL US will be performed on all patients, and patients will be blinded to the assigned group.

The treating medical team will be blind to the CAVAL US results of the control group.

Independent clinicians adjudicating 90-day events will not participate in patient follow-up, and will be blind to the assigned group.