Assessment of early anthracycline-induced cardiotoxicity and liver injury with T2 and T2* mapping in rabbit models

OBJECTIVES

To evaluate the early prevalence of anthracycline-induced cardiotoxicity (AIC) and anthracycline-induced liver injury (AILI) using T2 and T2* mapping and to explore their correlations.

MATERIALS AND METHODS

The study included 17 cardiotoxic rabbits that received weekly injections of doxorubicin and magnetic resonance imaging (MRI) every 2 weeks for 10 weeks. Cardiac function and T2 and T2* values were measured on each period. Histopathological examinations for two to five rabbits were performed after each MRI scan. The earliest sensitive time and the threshold of MRI parameters for detecting AIC and AILI based on these MRI parameters were obtained. Moreover, the relationship between myocardial and liver damage was assessed.

RESULTS

Early AIC could be detected by T2 mapping as early as the second week and focused on the 7th, 11th, and 12th segments of left ventricle. The cutoff value of 46.64 for the 7th segment had the best diagnostic value, with an area under the curve (of 0.767, sensitivity of 100%, and specificity of 52%. T2* mapping could detect the change in iron content for early AIC at the middle interventricular septum and AILI as early as the sixth week (p = 0.014, p = 0.027). The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver (r = 0.39, p = 0.002).

CONCLUSION

T2 and T2* mapping showed value one-stop assessment of AIC and AILI and could obtain the earliest MRI diagnosis point and optimal parameter thresholds for these conditions.

CLINICAL RELEVANCE STATEMENT

Anthracycline-induced cardiotoxicity could be detected by T2 mapping as earlier as the second week, mainly focusing on the 7th, 11th, and 12th segments of left ventricle. Combined with T2* mapping, hepatoxicity and supplementary cardiotoxicity were assessed by one-stop scan.

KEY POINTS

• MRI screening time of cardiotoxicity was as early as the second week with focusing on T2 values of the 7th, 11th, and 12th segments of left ventricle. • T2* mapping could be used as a complement to T2 mapping to evaluate cardiotoxicity and as an effective index to detect iron change in the early stages of chemotherapy. • The T2* values of the middle interventricular septum showed a significant positive association with the T2* values of the liver, indicating that iron content in the liver and heart increased with an increase in the chemotherapeutic drugs.

Assessment of early anthracycline-induced cardiotoxicity using segmental strain of cardiac magnetic resonance compared with global strain and functional parameters: an animal study

Background

The identification of anthracycline-induced cardiotoxicity holds significant importance in guiding subsequent treatment strategies, and recent research has demonstrated the efficacy of cardiac magnetic resonance (CMR) global strain analysis for its diagnosis. On the other hand, it is noteworthy that abnormal global myocardial strain may exhibit a temporal delay due to different cardiac movement in each segment of the left ventricle. To address this concern, this study aims to assess the diagnostic utility of CMR segmental strain analysis as an early detection method for cardiotoxicity.

Methods

A serials of CMR scans were performed in 18 adult males New Zealand rabbits at baseline time (n=15), followed by scans at week 2 (n=15), week 4 (n=9), week 6 (n=6), and week 8 (n=5) after each week's anthracycline injection. Additionally, following each CMR scan, two to three rabbits were euthanized for pathological comparison. Cardiac functional parameters, global peak strain parameters, segmental peak strain parameters of the left ventricle, and the presence of myocardial cells damage were obtained. A mixed linear model was employed to obtain the earliest CMR diagnostic time. Receiver operating characteristic (ROC) analysis was performed to get the parameter threshold indicative of cardiotoxicity.

Results

The left ventricular ejection fraction decreased at week 8 (P=0.002). There were no statistical differences in global strain throughout the experiment period (P>0.05). Regarding segmental strain analysis, the peak segmental radial strain of the apical lateral wall exhibited a decrease starting from week 2 and reached its lowest point at this week (P=0.011). Conversely, peak segmental circumferential strain of the apical anterior wall showed an increase at week 2 and reached its peak at week 6 (P=0.026). The cutoff strain value by ROC analysis for these two walls were 46.285 and -16.920, with the respective areas under the curve (AUC) 0.593 [specificity =0.267, sensitivity =1.000, 95% confidence interval (CI): 0.471-0.777] and 0.764 (specificity =0.733, sensitivity =0.784, 95% CI: 0.511-0.816). Peak segmental longitudinal strain of the apical anterior and apical lateral wall showed relatively delayed changes, occurring in the 4th week (P=0.030 and P=0.048), the cutoff values for these strains were -12.415 and -15.960, with corresponding AUCs of 0.645 (specificity =0.333, sensitivity =0.955, 95% CI: 0.495-0.795) and 0.717 (specificity =0.433, sensitivity =0.955, 95% CI: 0.566-0.902), respectively. Notably, the myocardial injury was also observed at the corresponding periods.

Conclusions

Based on experimental evidence, the peak segmental strain of the apical lateral and anterior wall, as determined by CMR, demonstrated an earlier detection of anthracycline-induced cardiotoxicity compared to peak global strain and cardiac function.

[Management of the nondisplaced type Herbert D1 scaphoid fracture with robot navigation combined with wrist arthroscopy]

To investigate the feasibility and the clinical efficiency of robot navigation combined with wrist arthroscopy in minimally invasive treatment of nondisplaced type Herbert D1 scaphoid fracture. A retrospective analysis was performed on 9 patients who underwent nondisplaced type Herbert D1 scaphoid fracture in Xuzhou Renci Hospital from December 2019 to January 2021. Before the operation and at the last follow-up, grip strength, pinching force, modified wrist Mayo score and visual analogue scale (VAS) of wrist pain were recorded and compared. The average follow-up time was 14.1 months (7.5-24.0 months). All the fractures achieved primary healing after an average of 13.3 weeks (10-18 weeks). The average flexion and dorsal extension activity of the injured wrist was 51.2°±9.4°, 68.0°±7.3°, and the radial and ulnar deviation was 19.3°±6.2°, 45.7°±7.8°, respectively. At the final follow-up, there were statistically significant differences in grip strength, pinch strength, wrist Mayo score and VAS when compared with those before the operation (all P<0.05). The results demonstrated that robot navigation combined with wrist arthroscopy for nondisplaced type Herbert D1 scaphoid fracture is effective and minimally invasive with a short recovery time and satisfactory healing rate.

[Study on the relationship between EPHX1 gene polymorphism and antioxidant capacity in patients with chronic obstructive pulmonary disease]

Objective: To explore the difference of mRNA, protein expression levels and the indexes of peripheral blood antioxidant capacity in peripheral blood lymphocytes of different EPHX1 genotypes in chronic obstructive pulmonary disease(COPD). Methods: A case-control study was conducted to collect peripheral blood samples of 220 stable chronic COPD patients with smoking history and 230 healthy smokers (control group) from October 2016 to February 2018 in the First Affiliated Hospital of Kunming Medical University, and the genetic testing was carried out according to the operation instructions of BigDye Terminator v1.1 DNA Sequencing Kit. Based on their EPHX1 exon 3 and exon 4 polymorphism status, the EPHX1 was classified into 4 groups, i. e., normal activity, slow activity, extremely slow activity and fast activity. Then COPD patients were allocated to either a slow activity group (slow and very slow activity) or a fast activity group (normal and fast activity) according to EPHX1 genotype and gene activity. The expression of EPHX1 mRNA and protein in peripheral blood lymphocytes were detected by qRT-PCR and Western blot, and indexes of serum antioxidant capacity was detected by corresponding kits. Results: (1)The 2(-ΔΔCt) of the control group was 1.000, and the 2(-ΔΔCt) of the COPD group was 1.052±0.023. There was no significant difference in the level of EPHX1 mRNA expression between the two groups (t=1.992 P=0.865). The level of EPHX1 mRNA expression in the slow activity group was not different significantly compared to that in the fast-active group (1.053±0.023 vs 1.048±0.021, t=1.133, P=0.260). (2)The level of EPHX1 protein expression by Western blot analysis showed that the EHPX1/GAPDH gray ratio was not different significantly between the COPD group and the control group (0.613±0.089 vs 0.602±0.075, t=0.805, P=0.422). The level of EPHX1 protein expression in the slow activity group was not significantly different compared to that in the fast activity group (0.606±0.088 vs 0.622±0.092, t=-0.786 P=0.434). (3)There were significant differences in indexes of antioxidant capacity between the control group and the COPD group (P<0.05). There were significant differences in indexes of antioxidant capacity between the slow activity group and the fast activity group of COPD patients (P<0.05). Conclusions: The different antioxidant capacity of COPD patients with different EPHX1 genotypes may be related to the polymorphism of EPHX1 gene affecting the activity of microsomal epoxidase, but not to the level of EPHX1 mRNA and protein expression.

[Effects of medial upper arm bilobed free flaps in the repair of two skin and soft tissue defects of hand]

Objective: To summarize the effects of medial upper arm bilobed free flaps in the repair of two skin and soft tissue defects of hand. Methods: From May 2014 to May 2016, 7 patients of two skin and soft tissue defects of hand with exposures of phalanges and tendons were treated in Xuzhou Renci Hospital, including 5 males and 2 females, aged from 19 to 41 years. Each defect area ranged from 3.0 cm×1.5 cm to 6.0 cm×3.0 cm. The medial upper arm bilobed free flaps were used to repair the defects, and the area of each lobe of the flaps ranged from 4.0 cm×2.0 cm to 8.0 cm×3.5 cm. The donor sites were sutured directly. The survival of the flaps was recorded. During follow-up, the recovery of donor and recipient sites was observed, the two-point discrimination distance of the flaps was measured, and the hand function was assessed by the trial criteria of the upper limb functional assessment of the Hand Surgery Society of the Chinese Medical Association. Results: All flaps survived smoothly, and the wounds and donor site incisions were healed. All patients were followed up, and the follow-up time lasted for 6 to 15 months. The color and texture of the flaps were similar to the surrounding normal skin, and the shape of the flaps was good. There was no obvious scar in the donor site, and the elbow joint function was normal. One patient developed ulnar numbness one month after operation and relieved after 3 months of treatment with neurotrophic drugs and local physiotherapy, etc. Six months after operation, the two-point discrimination distance of the flaps was 5.5-8.0 mm, and the hand function evaluation was excellent in 3 cases, good in 3 cases, and middle in 1 case. Conclusions: The medial upper arm bilobed free flap has both good texture and good appearance, and the scar of donor site is concealed. It is a good method to repair two skin and soft tissue defects of hand.