Chronic liver diseases are a group of diseases in which the liver is subjected to a variety of injuries over a long period of time， resulting in irreversible pathological changes that last longer than 6 months. Emodin （EMO） is a natural anthraquinone derivative derived from Rheum officinale， and its pharmacological effect has been extensively studied， exhibiting a variety of biological properties and involving multiple signaling molecules and pathways. Western medicine or surgical treatment is currently the main treatment regimen for chronic liver diseases， and the advance in treatment is limited by various reasons such as side effects and high costs. Due to its natural origin and efficacy， EMO has unique advantages in the treatment of chronic liver diseases and has now become a research hotspot. This article summarizes the therapeutic effect of EMO on chronic liver diseases and its mechanism， in order to provide a certain scientific basis for the traditional Chinese medicine treatment of chronic liver diseases and the development of drugs in clinical practice.

Diabetes is a very complex endocrine disease whose common feature is the increase in blood glucose concentration. Persistent hyperglycemia can lead to blindness, kidney and heart disease, neurodegeneration, and many other serious complications that have a significant impact on human health and quality of life. The number of people with diabetes is increasing yearly. The global diabetes prevalence in 20-79 year olds in 2021 was estimated to be 10.5% (536.6 million), and it will rise to 12.2% (783.2 million) in 2045. The main modes of intervention for diabetes include medication, dietary management, and exercise conditioning. Medication is the mainstay of treatment. Marketed diabetes drugs such as metformin and insulin, as well as GLP-1 receptor agonists, are effective in controlling blood sugar levels to some extent, but the preventive and therapeutic effects are still unsatisfactory. Peptide drugs have many advantages such as low toxicity, high target specificity, and good biocompatibility, which opens up new avenues for the treatment of diabetes and other diseases. Currently, insulin and its analogs are by far the main life-saving drugs in clinical diabetes treatment, enabling effective control of blood glucose levels, but the risk of hypoglycemia is relatively high and treatment is limited by the route of delivery. New and oral anti-diabetic drugs have always been a market demand and research hotspot. Inhibitor cystine knot (ICK) peptides are a class of multifunctional cyclic peptides. In structure, they contain three conserved disulfide bonds (C3-C20, C7-C22, and C15-C32) form a compact “knot” structure, which can resist degradation of digestive protease. Recent studies have shown that ICK peptides derived from legume, such as PA1b, Aglycin, Vglycin, Iglycin, Dglycin, and aM₁, exhibit excellent regulatory activities on glucose and lipid metabolism at the cellular and animal levels. Mechanistically, ICK peptides promote glucose utilization by muscle and liver through activation of IR/AKT signaling pathway, which also improves insulin resistance. They can repair the damaged pancrease through activation of PI3K/AKT/Erk signaling pathway, thus lowering blood glucose. The biostability and hypoglycemic efficacy of the ICK peptides meet the requirements for commercialization of oral drugs, and in theory, they can be developed into natural oral anti-diabetes peptide drugs. In this review, the structural properties, activity and mechanism of ICK pattern peptides in regulating glucose and lipid metabolism were summaried, which provided a reference for the development of new oral peptides for diabetes.

Objective:To explore the value of fetal heart quantification technology in assessing the morphology and function of the fetal heart during normal pregnancy.Methods:This prospective cohort study selected normal fetuses from healthy pregnant women who underwent prenatal ultrasound examinations at Hunan Provincial People's Hospital from January 2023 to October 2024. Using the GE Voluson E10 color Doppler diasonography, routine obstetric ultrasound and fetal echocardiography were performed to assess fetal growth and development and to exclude intracardiac and extracardiac malformations. Clear four-chamber view (4CV) dynamic images of the heart showing the endocardium (duration ≥3 s) were collected. Speckle-tracking analysis was performed using fetal heart quantification software. The measured indicators included the global spherical index (GSI), end-diastolic length of the heart (L-ED), end-diastolic width of the heart (W-ED), and the global longitudinal strain (GLS), fractional area change (FAC), and 24-segment spherical index (SI) of the left ventricle (LV) and right ventricle (RV). The cases were divided into five groups based on gestational age at the time of prenatal ultrasound: 20 +0 to 23 +6, 24 +0 to 27 +6, 28 +0 to 31 +6, 32 +0 to 35 +6, and 36 +0 to 40 +6 weeks. One-way analysis of variance, two independent samples t-test, univariate linear regression analysis, and Pearson correlation analysis were used to explore the differences in the above indicators among different gestational age groups and their correlation with gestational age. Results:A total of 200 pregnant women were included in the cohort, four cases were excluded due to poor image quality that prevented accurate tracking and measurement of relevant indicators. Ultimately, 196 cases (20 +0 to 23 +6 weeks 40 cases, 24 +0 to 27 +6 weeks 34 cases, 28 +0 to 31 +6 weeks 41 cases, 32 +0 to 35 +6 weeks 48 cases, and 36 +0 to 40 +6 weeks 33 cases) were included in the study, with a successful image analysis rate of 98.0%. (1) There were statistically significant differences in 4CV L-ED, 4CV W-ED, LV-FAC, and RV-FAC among the groups at 20 +0 to 23 +6, 24 +0 to 27 +6, 28 +0 to 31 +6, 32 +0 to 35 +6, and 36 +0 to 40 +6 weeks [4CV L-ED: 28.0±3.0, 32.6±4.3, 40.9±4.3, 46.7±4.8, 53.1±5.8, F=3.72; 4CV W-ED: 21.9±1.8, 25.1±4.2, 31.7±3.0, 37.4±4.0, 42.0±4.9, F=2.61; LV-FAC: (51.4±8.0)%, (49.0±10.4)%, (47.3±7.3)%, (43.1±7.5)%, (40.7±8.2)%, F=2.94; RV-FAC: (49.9±10.8)%, (46.2±12.0)%, (46.3±8.3)%, (43.2±8.0)%, (41.9±5.6)%, F=3.09; all P<0.05].(2) The size of the normal fetal heart gradually increased with gestational age, while the heart morphology remained relatively stable (4CV L-ED and 4CV W-ED were positively correlated with gestational age, with regression coefficients of 1.313 and 1.325, respectively, both P<0.001;LV-FAC and RV-FAC were negatively correlated with gestational age with regression coefficients of -0.783 and -0.552, respectively, both P<0.001; GSI, LV-GLS and RV-GLS had no correlations with gestational age, all P>0.05). (3) The SI of LV segments 1 to 17 were higher than the SI of the corresponding RV segments, and the SI of RV segments 20-24 were higher than that of the corresponding LV segments (all P<0.001). Conclusion:Fetal heart quantification technology has a certain value in the assessment of fetal cardiac morphology and function.

Objective To explore the spatiotemporal expression patterns of Patched 1(Ptch1)and insulin enhancer binding protein-1(Isl 1)in mouse embryonic foregut and their relationship with the early development of trachea-main bronchus.Methods The foregut of 60 mouse embryos at E9.5-12.5 was separated for the detection of Isl1 and sonic hedgehog(Shh)protein by Western blotting.Serial paraffin sections of 6 mouse embryos at E9.5-14.5 were taken for immunohistochemical staining and immunofluorescence double staining with Isl1,Ptch1,forkhead box protein A2(Foxa2),type Ⅱ collagen α1 chain(Col2a1)and α-smooth muscle actin(α-SMA),as well as HE staining and Masson staining.Results The expression trend of Isl1 and Shh in foregut endoderm at E9.5-12.5 was similar,and the peak of Shh expression was later than Isl1.The foregut developed into the trachea at E9.5-12.5,Ptch1 was expressed in the thickening and protrusion of the respiratory endoderm,the laryngal-tracheal groove and the solid cell cord,accompanied by the increase and aggregation of Isl1-positive mesenchymal cells,forming a characteristic pyramidal structure centered on the respiratory endoderm and the solid cell cord;The main bronchus appeared at E12.5-13.5,Ptch1 was only expressed in its lateral wall,accompanied by the accumulation of Isl1-positive mesenchymal cells;The trachea-main bronchial epithelium lost Ptch1 expression and the surrounding Isl 1-positive mesenchymal cells also decreased rapidly at E13.5-14.5.Co12a1-positive chondrocytes first appeared in the Isl1-positive mesenchymal area adjacent to the Ptch1-positive epithelium at E12.5;Col2a1-positive cartilage was nested within the Isl1-positive mesenchymic area in a"C"shape and expanded in a proximal-distal pattern at E12.5-13.5;Col2a1-positive cartilage extended to the dorsal trachea beyond the Isl1-positive mesenchyma and encircles α-SMA positive smooth muscle in a circular manner at E14.5.Conclusion The expression of Ptch1 in the foregut endoderm is involved in the development and morphogenesis of the trachea-main bronchus epithelium,and is closely related to the proliferation and aggregation of Isl1-positive mesenchyme in the trachea-main bronchial wall,Subsequently,they jointly determine the time,location and extent of airway cartilage.

Objective:To compare minimally invasive surgery with traditional open surgery, analyze the current application status of health economic evaluations in the treatment of digestive tract cancers, such as esophageal cancer, gastric cancer, and colorectal cancer by minimally invasive surgery and provide evidence for the rational selection of clinical treatment, alleviation of disease-related economic burdens, and rational allocation of healthcare resources.Methods:By using five databases, i.e. China National Knowledge Infrastructure, Wanfang data, Chinese Biomedical Literature Database, PubMed, and Embase, a database was established to retrieve all the papers about health economic studies of minimally invasive surgery for esophageal cancer, gastric cancer, and colorectal cancer published until December 31, 2023. Literature was analyzed by using software NoteExpress 3.8, and data were processed using Excel 2021. The quality of included papers was evaluated using the CHEERS 2022 checklist, and Meta-analysis was conducted by using software Stata 17.0.Results:A total of 10 919 relevant papers were retrieved, and 59 studies were included. Only 14 studies (23.7%) used standard health economic evaluation methods. Meta-analysis results revealed no significant differences in direct medical expenditure and total expenditure between minimally invasive surgery and open surgery. However, the expenditure for minimally invasive surgery exhibited a significant increase [mean difference ( MD)=5 973.12 yuan, P<0.001], while hospital stay and indirect expenditure significantly decreased ( MD: -4.85 days and -733.79 yuan, P<0.001). In China, for gastric cancer, the direct medical expenditure of endoscopic surgery was lower than that of open surgery ( MD=-33 000.00 yuan) with no significant difference ( P<0.001). In colorectal cancer cases, the direct medical and surgical expenditures for laparoscopic surgery were higher than those for open surgery ( MD: 4 277.94 yuan and 4 267.80 yuan, P<0.001), while the indirect and total medical expenditures decreased ( MD: -768.34 yuan and -159.10 yuan). Hospital stays in patients who had minimally invasive surgery for all three types of cancer were shorter than those who had open surgery ( P<0.001). Conclusions:In the treatment of gastrointestinal cancer, compared with open surgery, minimally invasive surgery shows higher expenditure, but has advantages, such as shorter hospital stay and lower indirect expenditure, and there were no significant differences in direct medical and total expenditures between the two approaches. When conducting health economic evaluation, factors such as postoperative complications, hospital stay, and patient's economic status should be considered for their impact on total medical expenditure. It is necessary to pay attention to the application of health economic evaluations in healthcare decision-making.

Objective:To explore the feasibility, safety, and short-term efficacy of a total pelvic floor resection procedure as a component of combined resection of pelvic organs for locally advanced or locally recurrent rectal cancer.Methods:This was a descriptive case series. Relevant clinical data of patients with locally advanced or locally recurrent rectal cancer without extrapelvic metastasis or with only oligometastasis who had undergone combined pelvic organ resection with resection of the entire pelvic floor in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Medical University from 1 January 2023 to 30 June 2024 were collected from a Chinese database of combined pelvic organ resection for rectal cancer. The study cohort comprised 143 patients, 74 of whom were male (51.7%) and 69 were female (48.3%); their ages averaged 54 (range: 31–75) years; 57 of the patients (39.9%) had locally advanced rectal cancer and 86 (60.1%) locally recurrent rectal cancer. In our institution, the pelvic floor is categorized into two anatomical layers: the levator ani/presacral anterior tissue, and the bone/ligament/pelvic floor soft tissue. The entire pelvic floor was resected en bloc after making incisions on both sides of the pelvic floor, followed by presacral sacral dissection, and abdominoperineal dissection of the anterior side of the pelvic floor. The main factors studied were related to the following: (1) surgical conditions, comprising the scope of surgical resection, operation time, intraoperative blood loss, tissue reconstruction; (2) postoperative recovery, comprising time to recovery of intestinal function, time to removal of drainage tubes, and time to healing of the empty pelvic cavity; and (3) postoperative complications, classified according to the international Clavien-Dindo classification. Results:Combined pelvic organ resection with entire pelvic floor resection was successfully completed in all patients. The operation time was 480 (390 to 1,020) minutes, intraoperative blood loss 800 (50 to 3,500) mL, and volume of blood transfused intraoperatively 1, 000 (400 to 7, 400). R0 resection was achieved in 116 cases (81.1%) and R1 resection in 27 (18.9%). The first layer of the pelvic floor wall (levator ani/sacral anterior tissue) was resected in 79 cases (55.2%) and the second layer of the pelvic floor wall (bone/ligament/pelvic floor soft tissue) in 64 (44.8%). The procedure was completed in the lithotomy position in 114 cases (79.7%) were and in the lithotomy + prone jackknife position in 29 (20.3%). The pelvic floor was reconstructed with mesh in 140 cases (97.7%) and with mesh plus pedicled omental flaps in 92 cases (64.3%). The urinary tract was reconstructed in 92 cases (64.3%). The time to recovery of intestinal function was 3.6 (2.0 to 7.0) days, to removal of drainage tubes 29.4 (24.0 to 54.0) days, and to healing of the empty pelvic cavity 36.2 (27.0 to 56.0) days. Twenty-three patients (16.1%) had Grade I - II complications and 36 (25.2%) Grade IIIa - IV complications. The median duration of follow-up was 15.5 (0.5 to 30.0) months. Six of the patients (4.2%) died, including two (1.4%) who died within 30 days after surgery.Conclusions:Pelvic floor en bloc resection has a high R0 resection rate and is a safe and feasible procedure for pelvic organ resection surgeries in patients with locally advanced or locally recurrent rectal cancer.

Objective:To explore the feasibility, safety, and short-term efficacy of a total pelvic floor resection procedure as a component of combined resection of pelvic organs for locally advanced or locally recurrent rectal cancer.Methods:This was a descriptive case series. Relevant clinical data of patients with locally advanced or locally recurrent rectal cancer without extrapelvic metastasis or with only oligometastasis who had undergone combined pelvic organ resection with resection of the entire pelvic floor in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Medical University from 1 January 2023 to 30 June 2024 were collected from a Chinese database of combined pelvic organ resection for rectal cancer. The study cohort comprised 143 patients, 74 of whom were male (51.7%) and 69 were female (48.3%); their ages averaged 54 (range: 31–75) years; 57 of the patients (39.9%) had locally advanced rectal cancer and 86 (60.1%) locally recurrent rectal cancer. In our institution, the pelvic floor is categorized into two anatomical layers: the levator ani/presacral anterior tissue, and the bone/ligament/pelvic floor soft tissue. The entire pelvic floor was resected en bloc after making incisions on both sides of the pelvic floor, followed by presacral sacral dissection, and abdominoperineal dissection of the anterior side of the pelvic floor. The main factors studied were related to the following: (1) surgical conditions, comprising the scope of surgical resection, operation time, intraoperative blood loss, tissue reconstruction; (2) postoperative recovery, comprising time to recovery of intestinal function, time to removal of drainage tubes, and time to healing of the empty pelvic cavity; and (3) postoperative complications, classified according to the international Clavien-Dindo classification. Results:Combined pelvic organ resection with entire pelvic floor resection was successfully completed in all patients. The operation time was 480 (390 to 1,020) minutes, intraoperative blood loss 800 (50 to 3,500) mL, and volume of blood transfused intraoperatively 1, 000 (400 to 7, 400). R0 resection was achieved in 116 cases (81.1%) and R1 resection in 27 (18.9%). The first layer of the pelvic floor wall (levator ani/sacral anterior tissue) was resected in 79 cases (55.2%) and the second layer of the pelvic floor wall (bone/ligament/pelvic floor soft tissue) in 64 (44.8%). The procedure was completed in the lithotomy position in 114 cases (79.7%) were and in the lithotomy + prone jackknife position in 29 (20.3%). The pelvic floor was reconstructed with mesh in 140 cases (97.7%) and with mesh plus pedicled omental flaps in 92 cases (64.3%). The urinary tract was reconstructed in 92 cases (64.3%). The time to recovery of intestinal function was 3.6 (2.0 to 7.0) days, to removal of drainage tubes 29.4 (24.0 to 54.0) days, and to healing of the empty pelvic cavity 36.2 (27.0 to 56.0) days. Twenty-three patients (16.1%) had Grade I - II complications and 36 (25.2%) Grade IIIa - IV complications. The median duration of follow-up was 15.5 (0.5 to 30.0) months. Six of the patients (4.2%) died, including two (1.4%) who died within 30 days after surgery.Conclusions:Pelvic floor en bloc resection has a high R0 resection rate and is a safe and feasible procedure for pelvic organ resection surgeries in patients with locally advanced or locally recurrent rectal cancer.

T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Objective:To explore the value of fetal heart quantification technology in assessing the morphology and function of the fetal heart during normal pregnancy.Methods:This prospective cohort study selected normal fetuses from healthy pregnant women who underwent prenatal ultrasound examinations at Hunan Provincial People's Hospital from January 2023 to October 2024. Using the GE Voluson E10 color Doppler diasonography, routine obstetric ultrasound and fetal echocardiography were performed to assess fetal growth and development and to exclude intracardiac and extracardiac malformations. Clear four-chamber view (4CV) dynamic images of the heart showing the endocardium (duration ≥3 s) were collected. Speckle-tracking analysis was performed using fetal heart quantification software. The measured indicators included the global spherical index (GSI), end-diastolic length of the heart (L-ED), end-diastolic width of the heart (W-ED), and the global longitudinal strain (GLS), fractional area change (FAC), and 24-segment spherical index (SI) of the left ventricle (LV) and right ventricle (RV). The cases were divided into five groups based on gestational age at the time of prenatal ultrasound: 20 +0 to 23 +6, 24 +0 to 27 +6, 28 +0 to 31 +6, 32 +0 to 35 +6, and 36 +0 to 40 +6 weeks. One-way analysis of variance, two independent samples t-test, univariate linear regression analysis, and Pearson correlation analysis were used to explore the differences in the above indicators among different gestational age groups and their correlation with gestational age. Results:A total of 200 pregnant women were included in the cohort, four cases were excluded due to poor image quality that prevented accurate tracking and measurement of relevant indicators. Ultimately, 196 cases (20 +0 to 23 +6 weeks 40 cases, 24 +0 to 27 +6 weeks 34 cases, 28 +0 to 31 +6 weeks 41 cases, 32 +0 to 35 +6 weeks 48 cases, and 36 +0 to 40 +6 weeks 33 cases) were included in the study, with a successful image analysis rate of 98.0%. (1) There were statistically significant differences in 4CV L-ED, 4CV W-ED, LV-FAC, and RV-FAC among the groups at 20 +0 to 23 +6, 24 +0 to 27 +6, 28 +0 to 31 +6, 32 +0 to 35 +6, and 36 +0 to 40 +6 weeks [4CV L-ED: 28.0±3.0, 32.6±4.3, 40.9±4.3, 46.7±4.8, 53.1±5.8, F=3.72; 4CV W-ED: 21.9±1.8, 25.1±4.2, 31.7±3.0, 37.4±4.0, 42.0±4.9, F=2.61; LV-FAC: (51.4±8.0)%, (49.0±10.4)%, (47.3±7.3)%, (43.1±7.5)%, (40.7±8.2)%, F=2.94; RV-FAC: (49.9±10.8)%, (46.2±12.0)%, (46.3±8.3)%, (43.2±8.0)%, (41.9±5.6)%, F=3.09; all P<0.05].(2) The size of the normal fetal heart gradually increased with gestational age, while the heart morphology remained relatively stable (4CV L-ED and 4CV W-ED were positively correlated with gestational age, with regression coefficients of 1.313 and 1.325, respectively, both P<0.001;LV-FAC and RV-FAC were negatively correlated with gestational age with regression coefficients of -0.783 and -0.552, respectively, both P<0.001; GSI, LV-GLS and RV-GLS had no correlations with gestational age, all P>0.05). (3) The SI of LV segments 1 to 17 were higher than the SI of the corresponding RV segments, and the SI of RV segments 20-24 were higher than that of the corresponding LV segments (all P<0.001). Conclusion:Fetal heart quantification technology has a certain value in the assessment of fetal cardiac morphology and function.

Objective:To quantitatively evaluate the effects of left bundle branch block（LBBB）on left ventricular structure，function and myocardial perfusion using left ventricular pressure-strain loop and single photon emission computed tomography（SPECT），and to investigate the relationship between myocardial work，myocardial perfusion and pathological changes of left ventricular remodeling in left bundle branch block induced cardiomyopathy（LBBB-CM）.Methods:Fourteen male beagle dogs were selected，and the main trunk of the left bundle branch was ablated to create an LBBB dog model. Electrocardiogram（ECG），transesophageal echocardiography and arterial blood pressure data of LBBB dogs were collected before and 12 months after the ablation of left bundle branch trunk. Global and segmental myocardial work parameters were obtained by left ventricular pressure-strain loop. The differences of above parameters between baseline and 12 months after the ablation of left bundle branch were compared. SPECT was performed in LBBB dogs 12 months after the creation of LBBB. The hearts were harvested for anatomy observation and histopathological analysis in LBBB dogs and another 7 male beagle dogs（normal control group）matched by age and weight. The correlation between myocardial perfusion（percentage of regional tracer uptake）and myocardial work parameters，myocardial fibrosis in LBBB dogs were analyzed.Results:Compared with baseline，the left ventricular end-diastolic volume of 12 months after the ablation increased［（20.78 ± 5.32）ml vs（26.71 ± 7.94）ml， P = 0.003］，left ventricular ejection fraction decreased［（59.17 ± 5.67）% vs（47.69 ± 5.45）%， P<0.001］；left ventricular global/segmental longitudinal strain，global/segmental constructive work and global/segmental work efficiency decreased（all P<0.05），left ventricular global/segmental wasted work increased（all P<0.001）. Heterogenous perfusion defect was observed in LBBB dogs by SPECT，compared with lateral wall segments，the percentage of regional tracer uptake of septum was decreased（all P<0.05）. Gross anatomical and myocardial pathological changes were manifested as cardiomegaly，flaky or focal grayish thickening of endocardium，cardiomyocyte degeneration and fibrosis. Compared with normal control group，the collagen fiber volume fraction（CVF）in all segmental endocardium and partial segmental myocardium of LBBB dogs were significantly increased（all P<0.05）. Percentage of regional tracer uptake was positively correlated with segmental myocardial work（SMW）and segmental myocardial efficiency（SWE）（ r s = 0.49，0.31；both P<0.001），and negatively correlated with CVF and segmental wasted work（SWW）（ r s = -0.51，-0.49；both P<0.001）. Conclusions:Isolated LBBB is not benign，which can result in left ventricular remodeling，decreased cardiac constructive function，abnormal myocardial perfusion，endocardial fibrosis and myocardial fibrosis.The parameters of myocardial work assecsed by echocardiograpgy and myocardial perfusion，as non-invasive examination，can to some extent reflect the degree of left ventricular remodeling in LBBB-CM.