Objective To investigate the correlations of the heart failure echocardiographic index (HFEI) with left ventricular function classification and serum brain natriuretic peptide (BNP) levels in heart failure patients with preserved ejection fraction (HFpEF), as well as its prognostic predictive value.

Methods A total of 139 patients with HFpEF were included as the study subjects. The occurrence of major adverse cardiovascular events (MACE) within one year of follow-up was recorded, and the patients were divided into good prognosis group and poor prognosis group according to the follow-up outcomes. The clinical data of the two groups of patients were compared, including general information, HFEI, left ventricular function classification, and serum BNP levels. Multivariate logistic regression analysiswas used to identify the influencing factors of poor prognosis. Pearson or Spearman correlation analysis was employed to evaluate the correlation between HFEI and left ventricular function classification and BNP levels. The receiver operating characteristic (ROC) curve was plotted to analyze the predictive efficacy of HFEI for poor prognosis.

Results During the one-year follow-up, 4 patients were lost during follow-up, and a total of 135 patients were included. The incidenceof poor prognosis was 21.48%(29/135). The proportions of patients with diabetes, hyperuricemia, a history of smoking, and the number of diseased vessels ≥3 in the poor prognosis group were all higher than those in the good prognosis group. The age, HFEI, left ventricular function classification, left ventricular end-diastolic diameter (LVEDD), left atrial diameter (LAD), and serum BNP and cardiac troponin I (cTnI) levels were also higher or larger in the poor prognosis group than those in the good prognosis group, with statistically significant differences (P < 0.05). Multivariate logistic regression analysis showed that HFEI, left ventricular function classification, and serum BNP levels at admission were all independent influencing factors for poor prognosis in patients with HFpEF (P < 0.001). After adjusting for left ventricular function classification and serum BNP levels, HFEI was still significantly correlated with poor prognosis (OR=1.688, 95%CI, 1.437 to 1.982, P < 0.001). Spearman correlation analysis showed a positive correlation between HFEI and left ventricular function classification (r=0.728, P < 0.05). Pearson correlation analysis showed a positive correlation between HFEI and serum BNP levels (r=0.745, P < 0.05). ROC curve analysis showed that the area under the curve of HFEI for predicting poor prognosis in patients with HFpEF was 0.819 (95%CI, 0.744 to 0.880), with a sensitivity and specificity of 86.21% and 75.47%, respectively.

Conclusion HFEI is positively correlated with left ventricular function classification and serum BNP levels in patients with HFpEF, and has good prognostic predictive value, which can provide a reference for clinical personalized treatment decisions.