Effect Of Splenectomy On Iron Metabolism Of Myocardium And Liver In Patients With Thalassemia Major

Objective: To investigate the effects of splenectomy on myocardial and hepatic iron metabolism in patients with severe β-thalassemia using magnetic resonance R2* parameters.Methods: 1.Examination Methods All patients underwent 3.0T SIEMRNS MRI multi-echo gradient scan of the heart and abdomen.The post-processing ROI interval analysis of the image was carried out on Syngo.via workstation and the curve was fitted by CMRTools combined with Excel.T2* parameter values of liver and heart were measured and R2* values were calculated.2.Case collection Group 1 A total of 442 patients with thalassaemia who underwent quantitative examination of iron deposition in heart and liver in our hospital from January 2017 to December 2020 were collected.According to whether splenectomy was performed before examination,they were divided into splenectomy group(116 cases)and non-splenectomy group(326 cases),respectively.In the second group,58 TM patients in the splenectomy group and non-splenectomy group were matched according to age,gender,blood transfusion volume and iron removal status.In the third group,14 pairs of TM patients in the splenectomy group and the non-splenectomy group were selected according to gender,blood transfusion and iron removal conditions,and basically the same time interval between MRI reexaminations.3.Statistical analysis: Wilcoxon rank sum test was used to compare the difference of R2* in liver and heart of the first group after splenectomy and non-splenectomy;Paired t-test was used to compare R2* values in myocardium and liver of the second group after splenectomy and non-splenectomy.Chi-square test was used to compare the proportion of normal and severe iron deposits in myocardium and liver between the first and second groups after splenectomy and those without splenectomy.Results: 1.There were 442 patients with thalassemia who completed MRI myocardial and liver iron quantitative examination,including 60 cases of re-examination,116 cases in the splenectomy group and 326 cases in the non-splenectomy group,among which 76 cases could be found out the exact time of splenectomy,and the other 40 cases were unknown.89 TM cases were found in the splenectomy group,and 208 TM cases were found in the non-splenectomy group.Observation on spleen cut cut with the spleen group-abdominal magnetic resonance T2-weighted images,spleen cut cut with the spleen group liver contour complete,full,intrahepatic bile ducts and blood vessels did not see clear unusual,gallbladder is no exception,liver area image signal is generally lower,some severe cases are "black liver" performance,spleen cut set of cases did not see the spleen shows,the spleen and spleen cut group was obviously increased in 263 cases,The spleen signal was significantly reduced in 233 patients,and the myocardial iron deposition was normal in 358 patients in the two groups.Comparison of visceral iron deposition in patients with severe β-thalassemia after splenectomy and without splenectomy: The myocardial R2* and liver R2* values of the splenectomy group were higher than those of the non-splenectomy group,and the differences were statistically significant.There was no statistical difference in the proportion of normal iron deposition between the two groups.The proportion of heart iron deposition and liver iron deposition in the non-splenectomy group were lower than that in the splenectomy group.2.In the second group,58 pairs of splenectomy and non-splenectomy matched groups received MRI scan of upper abdomen and myocardium at 3.0 T SIEMRNS MRI.In the splenectomy group,MRI scan was performed at an average of 42 months after splenectomy,and the maximum age difference between the two groups was no more than 6 months.After statistical comparison and analysis,there were no statistically significant differences in age,gender and myocardial R2* between the two groups.The R2* in liver of the splenectomy group was higher than that of the non-splenectomy group.Conclusion :(1)Most patients with β-thalassemia major have normal iron deposition in myocardium,while a few patients have normal iron deposition in liver.(2)Splenectomy may increase the proportion of severe iron deposition in liver and myocardium in patients with thalmus;(3)The spleen acts as an iron storage organ and buffer to maintain a stable level of iron metabolism in the liver,splenectomy aggravates iron deposition in the liver of patients with severeβ-thalassemia.