Use of gated myocardial perfusion imaging to assess left ventricular mechanical synchrony in patients with chronic heart failure and its relationship to New York heart functional class

Objectives To investigate the application value of gated myocardial perfusion imaging (GMPI) in the evaluation of left ventricular mechanical synchrony in patients with chronic heart failure and its relationship with the New York cardiac functional class, and to analyze the influencing factors of left ventricular mechanical synchrony disorder in patients with chronic heart failure.

Methods The clinical data of 81 patients with chronic heart failure admitted to Yan'an Hospital Affiliated to Kunming Medical University from January 2020 to December 2021 were selected, including 56 males and 25 females, aged (56.1±15.6) years, and 23 healthy subjects admitted during the same period were included as healthy control group. GMPI indicators (including left ventricular ejection fraction (LVEF), peak filling rate (PFR), left ventricular end-systolic volume (LVESV), left ventricular end-diastolic volume (LVEDV), phase standard deviation (PSD), phase histogram bandwidth (PHB), and summed rest score (SRS)) and laboratory tests (including hypersensitivity C-reactive protein (Hs-CRP) and N-terminal pro-B-type natriuretic peptide (NTpro-BNP)) of all subjects were collected, and the interval between GMPI examination and laboratory examination was no more than 7 days. Kruskal Wallis test and Spearman correlation analysis were used to analyze the relationship between GMPI, Hs-CRP, NTpro-BNP and classification of nyha heart function in patients with chronic heart failure. The independent samples between two groups were compared by t test or Mann-Whitney U test, and the inter-group comparison of counting data was performed by Chi-square test or Fisher exact probability method. Logistic regression analysis was conducted to explore the effects of different factors on left ventricular mechanical synchrony in patients with chronic heart failure.

Results There were significant differences of LVEF, LVEDV, LVESV, PFR, PHB, PSD, Hs-CRP and NTpro-BNP in the cardiac function grade Ⅰ group, the cardiac function grade Ⅱ group and the cardiac function grade Ⅲ-Ⅳ groups (H=23.846, 14.791, 21.089, 6.251, 18.892, 20.347, 19.171, 35.654, all P<0.05). There were significant differences in LVEF, LVEDV, LVESV, PFR, PSD and NTpro-BNP between the patients with chronic heart failure in the cardiac function grade Ⅰ group and the healthy control group (t=4.084, Z=3.462, 3.038, 3.519, 3.489, 2.203; all P<0.05). The levels of SRS, LVESV, LVEDV, PHB, PSD, NTpro-BNP, Hs-CRP were positively correlated with the New York cardiac functional class (r=0.235, 0.547, 0.474, 0.481, 0.458, 0.671, 0.439; all P<0.05). Univariate analysis showed that there were statistically significant differences in age, LVEF, PFR, heart rate, LVEDV, LVESV, SRS, Hs-CRP and NTpro-BNP between patients with left ventricular mechanical synchrony and those with non-synchronous chronic heart failure (t=2.550, χ²=6.146, t=4.042, Z=3.149, χ²=5.335, χ²=5.993, Z=4.978, χ²=6.154, Z=4.381; all P<0.05); The results of multivariate regression analysis showed that LVEF and SRS were independent influencing factors for the occurrence of left ventricular mechanical synchronization dysregulation in patients with chronic heart failure (B=−0.166, 0.278; B standard error=0.068, 0.130; Wald χ²=5.927, 4.584; P=0.015, 0.032; OR=0.847, 1.320; 95%CI=0.741-0.968, 1.024-1.702).

Conclusion LVEF, LVEDV, LVESV, PFR, PSD, NTpro-BNP may have potential value in early diagnosis of chronic heart failure. LVEF, LVESV, PFR, LVEDV, PHB, PSD, NTpro-BNP and Hs-CRP have suggestive effects on the severity of cardiac function impairment in patients with chronic heart failure, and NTpro-BNP, LVEF and LVESV have better suggestive effects. Increased SRS and decreased LVEF were independent predictors of left ventricular mechanical synchrony in patients with chronic heart failure.