Patients with acute decompensated heart failure (HF) have a significantly high risk of death and HF re-hospitalization during the vulnerable phase post discharge. Therefore, early post-discharge management is crucial, and the cornerstone of HF treatment-particularly for HF with reduced ejection fraction (HFrEF)-is guideline-directed medical therapy (GDMT), a comprehensive pharmacotherapeutic strategy supported by robust clinical evidence. Timely titration of GDMT, especially within the first few weeks after discharge, has been shown to improve clinical outcomes, reduce readmissions, and enhance long-term prognosis. However, ensuring optimal follow-up and therapeutic adjustments remains a major challenge in real-world practice. Atrial fibrillation (AF) is a common comorbidity in patients with HF, especially in those with severe HF. The presence of AF significantly complicates the clinical course and worsens the prognosis of HF.

Advances in wearable technology have made continuous, non-invasive monitoring of vital signs, arrhythmia burden, and physical status increasingly feasible. Devices such as smartwatches and ECG belts can provide real-time physiological data, offering new opportunities for remote and proactive disease management. Despite the growing availability of such data, the complex interplay between AF and HF demands highly personalized management. Currently, there is a lack of high-quality clinical evidence on how to effectively integrate wearable device data into personalized strategies for this specific patient population.

This is an open-label, multi-center, endpoint-blinded, parallel-group randomized clinical trial supported by the American Heart Association. The primary objective is to determine whether wearable device-assisted digital consultations can optimize GDMT in patients with AF complicated by acute decompensated HF. The study plans to enroll 400 participants, who will be randomly assigned to either a wearable device-assisted intervention group or a conventional treatment control group. The primary endpoint is the change in HF GDMT score 3 months after randomization.

Apple Inc. provided funding, devices, and technical support for this study. Apple was not a sponsor of the trial and was not involved in its execution, data analysis, interpretation, or manuscript preparation.

Inclusion Criteria:

1. Age ≥ 18 years
2. Subjects diagnosed with acute decompensated heart failure (ADHF) :1)Heart failure with reduced ejection fraction (HFrEF), defined as left ventricular ejection fraction (LVEF) ≤ 40%;2)New York Heart Association (NYHA) functional class II-IV;3)NT-proBNP > 2500 pg/mL or BNP > 600 pg/mL
3. Atrial fibrillation (AF) diagnosed during hospitalization (documented AF episode lasting > 30 seconds on electrocardiogram [ECG] within the past 12 months)

Exclusion Criteria:

1. Intolerance to heart failure pharmacotherapy
2. Severe anemia, uncorrected thyroid disease
3. ST-segment elevation myocardial infarction (STEMI) within 3 months
4. Known complex congenital/secondary heart disease; infiltrative cardiomyopathy (e.g., cardiac amyloidosis, sarcoidosis, lymphoma, or endomyocardial fibrosis); myocarditis; constrictive pericarditis; cardiac tamponade; hypertrophic cardiomyopathy; stress cardiomyopathy (Takotsubo cardiomyopathy); or uncorrected primary valvular heart disease requiring surgical intervention.
5. Previous or planned major cardiac surgery or mechanical circulatory support within 6 months, including coronary artery bypass grafting, cardiac valve repair or replacement, ventricular assist device or mechanical circulatory support device implantation, and heart transplantation.
6. Current use of or planned implantation of a pacemaker.
7. Contraindications to wearing a smartwatch (e.g., limb disability or known allergy to rubber/metal materials)
8. Inability to access the Internet or lack of proficiency in operating smart devices
9. Pregnant or lactating women
10. Organ transplantation within the past 12 months
11. Expected survival time of less than 1 year for any reason
12. Refusal to participate or inability to comply with follow-up requirements
13. Deemed ineligible for participation in the study by the investigators