This study aims to investigate whether using a low-sodium substitute salt can help improve outcomes for patients with heart failure. Specifically, it will examine if the low-sodium substitute salt can reduce death rates, hospital readmissions, and emergency visits, as well as improve the quality of life for these patients.

The study will involve multiple centers and use a randomized, double-blind, controlled design, where participants will be randomly assigned to either the intervention group (who will use the low-sodium substitute salt ) or the control group (who will use regular salt). Participants will be followed up for at least a year, assessing outcomes including all cause mortality, heart failure hospitalizations, emergency visits, and changes in quality of life as measured by a questionnaire.

Eligible participants will be between 18 and 75 years old, have been hospitalized for heart failure in the past year, and have stable heart failure. The study will exclude individuals with severe heart failure, uncontrolled health conditions, or other factors that may interfere with participation.

The main goals are to determine if reducing sodium intake through the low-sodium substitute salt leads to better health outcomes in heart failure patients over a year. Participants will be followed up at 3, 6, 9, and 12 months.

This research will help provide evidence for whether a simple dietary change, like using a low-sodium substitute salt , can make a meaningful difference in managing heart failure

Inclusion Criteria:

1. Aged between 18 and 75 years;
2. Hospitalized due to heart failure in the past year;
3. NYHA functional class II-III;
4. Echocardiographic evidence of LVEF < 40% within the past 6 months;
5. Receiving guideline-directed medical therapy for heart failure;
6. Stable heart failure status, defined as heart failure stability for more than 4 weeks, with no increase in diuretic dose within the past 4 weeks;
7. Having a primary caregiver and frequently dining together at home;
8. Consuming commercially processed food no more than once a week;
9. Providing written informed consent.

Exclusion Criteria:

1. End-stage heart failure;
2. Hospitalization due to cardiovascular causes within the past month;
3. Uncorrected hyponatremia (Na < 130 mmol/L);
4. Dialysis-dependent patients, or eGFR < 20 mL/min/1.73m²;
5. Uncontrolled hyperglycemia, with fasting blood glucose > 16 mmol/L;
6. Malignant cancer patients with a life expectancy of less than 1 year;
7. Conditions that, in the investigator's opinion, may interfere with adherence to the protocol, such as habitual reliance on takeout meals or dining at company cafeterias;
8. Planned hospitalization during the study period;
9. Unexplained weight loss greater than 5 kg in the past year;
10. The subject or family members have concerns about using the salt substitute in this study, or are planning for pregnancy, pregnant, or breastfeeding;
11. Another family member is already participating in this study;
12. The subject or family members are participating in other interventional clinical trials.