Cardiac MRI for clinical dilated cardiomyopathy: Improved diagnostic power via combined T1, T2, and ECV

INTRODUCTION

Early diagnosis of patients with dilated cardiomyopathy (DCM) remains challenging. Cardiac MR can correlate myocardial changes with their pathological basis. There have been some previous studies on the effect of T1 mapping in DCM, but there is limited data on the incremental value of T2 mapping for DCM in routine clinical practice. This study will examine whether the combination of MRI T1 and T2 mapping offers greater advantages in the diagnosis of DCM.

METHODS

The study included 28 patients with DCM and 21 healthy controls. CMR evaluation included late gadolinium enhancement (LGE), T1 mapping, extracellular volume (ECV) fraction and T2 mapping. The DCM group was divided into LGE (+) and LGE (-) subgroups. The main modes of LGE are subendocardial, midwall, subepicardial, or transmural. T1 values, T2 values, and ECV in the 16 segments myocardial levels were measured by post-processing software. Student's t-tests or Mann-Whitney U test was used to compare between two groups, and one-way ANOVA or Kruskal-Wallis H test was used to compare between multiple groups, with p values corrected by Bonferroni. The difference was considered statistically significant at P < 0.05. ROC curve analysis was used to compare the area under the curve (AUC) of each index and its combined value, and the cut-off value, sensitivity and specificity were determined by Jordan's index.

RESULTS

Mean native myocardial T1, ECV and T2 were significantly higher in the DCM group compared to controls (p ≤ 0.001, respectively). The best cut-off values for T1, T2 and ECV to discriminate DCM from controls were 1184 ms, 40.9 ms and 29.2%, respectively. The AUC of T1, ECV and T2 were 0.87, 0.89, and 0.83, respectively. The combined AUC of the three values was 0.96.

CONCLUSION

Native T1 value and ECV overcome some of the limitations of LGE, and the T2 helps to understand the extent of myocardial damage. The combination of T1 and T2 mapping techniques can reveal fibrotic and oedematous changes in the early stages of DCM, providing a more comprehensive assessment of DCM and better guidance for individualised clinical management of patients.

IMPLICATIONS FOR PRACTICE

We suggest that the addition of T2 mapping to the routine CMR examination of patients with suspected DCM, and the combined assessment of T1mapping and T2 mapping can provide complementary information about the disease and improve the early diagnosis of DCM.

[Efficacy and safety analysis of the combination of cladribine, cytarabine, granulocyte colonystimulating factor (CLAG) regime in patients with refractory or relapsed acute myeloid leukemia]

目的

分析CLAG方案（克拉屈滨＋阿糖胞苷+ G-CSF）对难治复发急性髓系白血病（AML）的疗效及安全性。

方法

回顾性分析2014年4月1日至2015年12月9日采用1个疗程CLAG方案治疗的33例难治复发AML患者的临床资料。

结果

33例难治复发AML患者中，男16例，女17例，中位年龄49(14~68）岁。按照WHO分类（第4版）诊断：伴有重现性遗传学异常AML 7例（21.2%），伴有多系病态造血AML 5例（15.2%），治疗相关AML 2例（6.1%），其他类型19例（57.5%）。NCCN危险分层低危、中危、高危组分别为6、18、9例，其中FLT3-ITD基因突变5例。复发16例，难治17例，既往化疗疗程中位数为2(1~36）个。经CLAG方案1个疗程化疗后，26例（78.8%）获得完全缓解（CR），难治组CR率低于复发组[64.7%（11/17）对93.8%（15/16），P=0.041]。5例FLT3-ITD基因突变患者均获CR。所有患者均出现4级白细胞减少和血小板减少和不同部位感染，3例因感染而早期死亡。5例患者CR后接受异基因造血干细胞移植。中位随访142(9~525) d，复发10例，死亡13例，中位无事件生存期为230(9~525）d，中位总生存期为419(9~525) d。获CR患者（26例）中位总生存期长于未缓解患者（7例）[447(165~525) d对52(9~162) d，P <0.001]。

结论

CLAG方案对难治复发AML疗效肯定，复发患者CR率高于难治患者。控制感染是治疗成功的关键。

Relationship between TLR4 and MCP2 expression levels and habitual abortion

Habitual abortion is associated with the altered expression of multiple genes. This study was carried out to investigate the relationship between expression of Toll-like receptor 4 (TLR4) and monocyte chemotactic protein 2 (MCP2 or CCL8) and habitual abortion. This was done by detecting and comparing their relative expression in peripheral blood and placental villi of patients and healthy fertile women. Based on our previous research, 85 subjects with habitual abortion (study group) and 40 healthy fertile women (control group), who were admitted to our hospital between June 2013 and December 2014, were enrolled in this study. After these subjects signed written informed consent, peripheral blood samples and villous tissues were collected, from which the total RNA was extracted. The expression of TLR4 and MCP2 was detected with quantitative reverse transcription-polymerase chain reaction, using GAPDH as a reference control. The expression of TLR4 and MCP2 in the peripheral blood and villous tissues of the study group was significantly higher than that of the control group (P < 0.05). A positive correlation was also observed between the changes in expression levels of TLR4 and MCP2. In conclusion, TLR4 and MCP2 expression correlated with the occurrence of habitual abortion. Detecting expression changes in TLR4 and MCP2 in the peripheral blood is a feasible method for predicting the occurrence of abortion in women of child-bearing age.

Red cell age and susceptibility to malaria during pregnancy

BACKGROUND

Increased susceptibility to malaria in pregnancy is well recognized, and has generally been assumed to be due to hormonal changes resulting in altered immunity. Based on previous work demonstrating enhanced parasite growth in young normal and thalassemic red blood cells, we hypothesized that in pregnancy increased malaria susceptibility may be due, in part, to the increase in the population of young red cells.

METHODS

FC27 strain of Plasmodium falciparum was cultured in the red cells and sera from healthy primigravida pregnant (n=9) and non-pregnant (n=9) women. Red cells from both pregnant and non-pregnant women were each placed in three cultures containing the sera from pregnant, non-pregnant and pooled control samples. Cultures were set up in triplicate and incubated for 144 hours. Parasite development and growth were assessed by slide microscopy.

RESULTS

At 96 hours the median parasite growth in cells from pregnant samples (5.7%) was significantly better than that in the non-pregnant cells (4.8%) (p=0.01). There was no significant difference in parasite growth in cultures with pregnant and non-pregnant sera. As expected, there were significant differences in parameters measuring red cell age between the cells from pregnant and nonpregnant samples: median red cell creatine (11.09 mg/dl) versus (6.90 mg/dl) (p=0.004) and median reticulocyte count (2.3%) versus (1.4%) (p=0.0006).

CONCLUSIONS

These preliminary results are consistent with the hypothesis that an increased population of young red cells may contribute to increased malaria susceptibility during pregnancy.

Invasion and growth of Plasmodium falciparum is inhibited in fractionated thalassaemic erythrocytes

Epidemiological and clinical studies have indicated that the thalassaemias may confer protection against malaria. The study reported here investigated this protective effect in vitro, using a new approach which controls for the potential effect of red cell size and age on the virulence of the parasite. A Percoll density gradient method was used to separate alpha- and beta-thalassaemic trait, haemoglobin H and normal red blood cells (RBC) into fractions of different density. Correlations between RBC density, age and size in fractions of all genotypes were established using red cell creatine as an index of cell age. The development of Plasmodium falciparum over 3 erythrocytic cycles (144 h) in whole blood as well as fractionated samples was monitored by slide microscopy and flow cytometry. A significantly reduced rate of parasite invasion and growth was demonstrated in RBC from all thalassaemic genotypes tested. Poor reinvasion rates were noted in the second and third cycles. Increased duration of culture and red cell age also had a greater negative impact on parasite growth in thalassaemic RBC. This poor growth rate was also associated with the arrest of parasite growth at the schizont stage (schizont maturation arrest) and the accumulation of abnormal, trophozoite/schizont stage parasites in the older thalassaemic RBC fractions. These findings suggest a defect in the number and viability of merozoites generated by parasites growing in thalassaemic RBC. Age related factors such as oxidant stress may play a key role in mediating this kind of protective mechanism and deserve further investigation.