Currently, the recommendations for sodium intake restriction for patients with heart failure are mostly based on expert consensus and observational evidence, whereas smaller randomized studies have actually suggested that strict dietary sodium reduction may be harmful in heart failure. In the present clinical trial pilot study, the investigators plan to collect data on enrollment rates, compliance, outcomes, and safety of a 12-week dietary intervention in heart failure patients, with prepared food containing two different levels of sodium (1,500 mg and 3,000 mg) daily, followed by a 12-week surveillance for safety and effectiveness. The goal is to inform the design of a fullscale clinical trial that will provide more definitive evidence for dietary sodium recommendations in heart failure.

Despite the intense research for improving outcomes in heart failure, evidence remains scarce (and mostly observational) for dietary sodium restriction, arguably the most widely recommended self-care measure for heart failure. In explicit acknowledgement of the evidence gaps and unclear benefits, the recent European Society of Cardiology guidelines have not assigned a level of evidence to sodium intake recommendations and the American College of Cardiology (ACC) and American Heart Association (AHA) guidelines do not provide a specific target level of sodium intake for patients with HF.

Although it seems reasonable to restrict sodium below <3000 mg/d in heart failure, it is currently unknown how "low" is appropriate for these patients.

This study will attempt to provide the basis to evaluate the above guidelines by determining, in consecutive HFrEF patients with EF ≤40% during an acute HF admission, the proportion of patients who: (1) are willing to participate in a 12-week feeding trial; (2) meet the trial eligibility criteria; and (C) subsequently continue to consume ≥3000 mg/d sodium 15-30 days post discharge despite discharge instructions. This will allow the investigators to estimate enrollment rates in a full-scale trial.

This study will randomize 50 eligible patients to prepared meal plans with either 1500 mg/d vs. 3000 mg/d sodium for 12 weeks .

The hypotheses of the present study are that (1) ≥ 90% of patients will be retained on the study by 12 weeks (or at first outcome or safety event) and (2) patients will be compliant with provided food ≥ 90% of the study days.

Study Primary Endpoints:

(i) Overall on-study retention and (ii) compliance with the prepared food, assessed via daily food diaries and 24-h urine collections at baseline, 4, 8, and 12 weeks.

Study Secondary Endpoints:

Estimate trends in (1) all-cause mortality, readmissions, and emergency room visits; (2) NT-pro-B-type natriuretic peptide levels; and (3) diet palatability and quality of life, between the two arms.

Safety endpoints:

Safety of the intervention assessed by vital sign and laboratory assessments. This pilot study is expected to yield critical information necessary and sufficient to design a full-scale clinical trial that will provide evidence for dietary sodium recommendations in heart failure.

Inclusion Criteria:

1. Age ≥21 years at screening
2. Recent (≤1 year) EF ≤40%
3. Standard HF treatment, including ACEI/ARB & beta-blockers & aldosterone antagonists, unless contraindicated or intolerant

5. Able to consume research diet (e.g. no dysphagia etc.) 6. Systolic blood pressure ≥100 mmHg 7. >3000 mg/d sodium excretion (by 24-hr urinary sodium)

Exclusion Criteria:

1. Institutionalized patients
2. Siogns or symptoms of instability in HF status
3. Communication barriers, including cognitive impairment; inability to communicate and understand and cooperate with the protocol
4. Severe non-cardiac illness that compromises life expectancy within the next 12 months or the ability to participate in the study (e.g. severe hepatobiliary disease, cancer underground chemo- or radiotherapy)
5. Any medical or surgical procedure planned in the next 6 months
6. Participants planning to move to a different state within 6 months
7. Participation in any other experimental protocol
8. Renal replacement therapy or Stage 4 or 5 chronic kidney disease