Objective To study the value of Heart Rate Deceleration runs（DRs） and Deceleration Capacity of rate（DC） in the prognosis assessment of patients with chronic heart failure whose ejection fraction is

partially preserved. Methods In this study

prospective cohort analysis was used to randomly select hospitalized patients with chronic heart failure（CHF） with NYHA grade Ⅱ

Ⅲ and Ⅳ in the Department of Cardiology of Nanxiang hospitalfrom April 2018 to October 2019. Color doppler ultrasonography was performed by a fixed professional physician. The left ventricular ejection fraction（LVEF） was measured. Patients were grouped according to the left ventricular ejection fraction

those with LVEF≥50% were in HFpEF group

patients with 35%

<

LVEF

<

50% were in HFmr-EF group

and patients with LVEF≤35% were in HFr EF group. At the same time

24-hour dynamic electrocardiogram was detected

DC value and DRs detection and HRV time domain were analyzed. All the patients were followed-up for 12 months.Adverse cardiac events during follow-up were recorded. We analyzed the predictive value of DRS and DC in patients with HFpEF. The sudden cardiac death and all-cause death were the primary endpoints

and the re-admission for heart failure was the secondary endpoint. Results In this study

we found that DC value

DRs（including DR4

DR2

DR8）

HRV all time domain indicators were significantly different in patients with chronic heart failure with different degrees of retention of ejection

and the difference was statistically significant（p

<

0.05）. In patients with LVEF>35%

DC and DRs showed significant difference in risk stratification between the event group and the non-event group（χ

2

=8.003

p=0.008）. ROC curve analysis showed that the area under the curve had statistical significance（DC=0.606

p=0.005; DR=0.581

p=0.032; DR2=0.0.588

p=0.037）. Conclusions DC

DR4 and DR2 still have certain prognostic value for chronic heart failure patients with LVEF>35%.