Cardiac-Related Lesions in Newly Diagnosed Patients with Acute Leukemia

Background:

More and more cases of leukemia with heart injury have been reported, mostly due to tumor cell infiltration, endothelial injury and high viscosity of leukemia cells in circulating blood. To evaluate whether the newly diagnosed acute leukemia patients have suffered heart-related injuries, and determine the possible related factors, we carried out this study.

Methods:

From January 2015 to August 2019, we retrospectively selected 408 patients from the Department of Hematology and Cardiology, Zhongnan Hospital of Wuhan University. There were 200 newly diagnosed acute leukemia patients (including 15 acute hyperleukocytic leukemia patients), 105 patients without cancer and no known heart disease, and 103 cases of confirmed coronary heart disease. We collected the basic information of patients, echocardiographic data and myocardial enzyme results. We also followed up all newly diagnosed acute leukemia patients for prognostic analysis.

All data were logarithmically transformed to make the data normally distributed. Normally distributed samples were compared using independent sample t-tests, Mann-Whitney U rank sum test was used for non-normally distributed samples and qualitative data was using chi-square test. The log-rank test was used to perform univariate analysis through Kaplan-Meier curves, and meaningful values were screened for multivariate COX regression analysis. The statistical analysis was performed with the SPSS software.

Results:

Compared with the control group, patients with newly diagnosed acute leukemia had already experienced some heart-related injuries. The average values of myocardial enzyme indexes such as CKMB,LDH,hs-cTnI,BNP and echocardiography indexes such as LV,EDV,ESV,SV,EF were all significantly different. But the degree of heart damage was lower than that of the coronary heart disease group. Compared with hyperleukocytic leukemia, non-hyperleukocytic leukemia had suffered more serious heart damage, especially myocardial enzyme indexes such as HBDH and LDH were significantly increased.

Analyze the relationship between age, gender, cardiovascular risk factors (hypertension, diabetes and smoking history), myocardial enzyme indexes, echocardiography indexes and survival, to screen for risk factors related to the prognosis of the disease. Variables with statistically significant effect measurement values include age (p<0.001), LDH (p=0.018), and EF (p=0.053). In addition, the meaningful variables in the previous single-factor analysis were subjected to multi-factor COX regression analysis, and age (HR = 1.515, 95 %CI, 0.994-2.311, P = 0.001), EF (HR = 0.526, 95% CI, 0.361-0.766, P=0.05) were independent factors related to the prognosis of patients.

Classification based on the clinical diagnosis of echocardiography in newly diagnosed acute leukemia patients, significant differences in myocardial enzymes and related indicators of echocardiography were included for ROC plots. The 3 indicators with the highest results for the area under the curve (AUC) from ROC plots were LV, EDV and HBDH, AUC were 0.721,0.619 and 0.615, respectively. This result revealed that the best predictor of leukemia myocardial damage was LV. It showed the predict ability of LV (AUC = 0.721, 95%CI = 0.643-0.799, P <0.001; sensitivity = 42.4%; specificity = 91.8%).

Conclusions：

According to our research, we have confirmed that the cardiac function of newly diagnosed acute leukemia patients is significantly different from that of patients without leukemia, and these differences will have an impact on the prognosis of patients. Among them, the best predictor of leukemia heart damage is LV, and EF is an independent risk factor for the prognosis of leukemia patients. In addition, newly diagnosed acute leukemia patients are more likely to have an increase in left ventricular diameter and a significant decrease in ejection fraction. Further research is needed to explore the specific mechanism in the future.