[Investigate the role of neutrophil extracellular traps in immune checkpoint inhibitor-associated myocarditis with programmed death protein-1 inhibitors involvement].

Objective: To investigate the role of neutrophil extracellular traps (NETs) in immune checkpoint inhibitor-associated myocarditis (ICIAM) with programmed death protein-1 (PD-1) inhibitors involvement, and to explore the therapeutic potential of targeting NETs in the treatment of ICIAM. Methods: Thirty 6-week-old male BALB/c mice were randomly divided into control group (n=10), myocarditis group (n=10), and treatment group (n=10). Apart from the control group, each mouse was subcutaneously injected with 100 µl of complete Freund's adjuvant containing 250 µg of mouse cardiac troponin I peptide on the 1st and 7th day. Starting on the 8th day, PD-1 inhibitor (15 µg/per mouse) was intraperitoneally injected every other day for a total of 5 times. Since 1 day before the beginning of PD-1+TnI injection, the treatment group was injected with PF-1355 (50 mg·kg-1·d-1) for 16 consecutive days. The mice's general state was observed during the whole process. Real-time fluorescence quantitative PCR (RTFQ-PCR) was carried out to evaluate the transcriptional regulation of neutrophil related chemokines, NETs, pyronecrosis related factors and proinflammatory cytokines. Immunohistochemistry, immunofluorescence and western blot were applied to determine the changes of pyrosis related molecules. Echocardiography showed the differences of main cardiac indexes while cardiac pathology compared the degree of inflammatory infiltration in 3 gruops. Results: The immunofluorescence intensity of myocardial NETs in the myocarditis group was significantly increased compared to the control group mice (2.49±0.08 and 0.99±0.26, P<0.001). The protein expression levels of pyroptosis-related NLRP3, cleaved-Caspase 1, Caspase 1, cleaved-GSDMD, GSDMD, IL-1ß and IL-18 in myocardial tissue of the model group were higher than those of the control group (all P<0.05). After treatment with PF-1355, compared to the myocarditis group, the left ventricular ejection fraction (LVEF) (73.58%±5.31% and 58.12%±3.19%, P<0.001) and left ventricular fraction shortening (LVFS) (39.78%±4.31% and 33.89%±2.19%, P<0.001) increased. H-E staining showed a reduction in inflammatory infiltration area in the treatment group compared to the myocarditis group (30.12%±3.57% and 14.92%±2.46%, P<0.001). The immunofluorescence intensity of NETs decreased in the treatment group compared to the myocarditis group (2.52±0.04 and 1.03±0.05, P<0.001). The levels of NLRP3 and other pyroptosis-related molecules were downregulated in the treatment group compared to the myocarditis group (all P<0.05). Conclusions: NETs lead to myocardial cell pyroptosis by activating the NLRP3 inflammasome in PD-1 inhibitor-associated myocarditis. The specific MPO inhibitor PF-1355 shows a therapeutic potential by regulating the formation of NETs, decreasing NLRP3 level and relieving myocardial pyroptosis, thus reducing myocardial damage.

[Efficacy of fenestrated atrial septal defect occulders on pulmonary hypertension dogs].

Objective: To explore the short-term efficacy of fenestrated atrial septal defect (ASD) occulders in the treatment of pulmonary arterial hypertension (PAH). Methods: Thirty-six healthy dogs were divided into the balloon atrial septostomy (BAS)+fenestrated ASD occulders group (n=12), BAS group (n=12) and non-septostomy group (n=12). PAH was induced by intra-atrial injection of dehydrogenized monocrotaline (1.5 mg/kg) in all dogs. Animals in the BAS+fenestrated ASD occulders group underwent atrial septal puncture and fenestrated ASD occulders implantation. Animals in the BAS group underwent balloon atrial septostomy. The non-septostomy group received no surgical intervention. The hemodynamic indexes and blood N-terminal pro-B-type natriuretic peptide (NT-proBNP) of dogs were measured before modeling, 2 months after modeling, 1, 3, and 6 months after surgery, respectively. Echocardiography was performed to observe the patency of the shunt and atrial septostomy of the dogs in the BAS+fenestrated ASD occulders group and BAS group at 1, 3, and 6 months after surgery. Three dogs were sacrificed in each group at 1, 3, and 6 months after surgery, respectively. Atrial septal tissue and fenestrated ASD occulders were removed to observe the patency and endothelialization of the device. Lung tissues were obtained for hematoxylin-eosin (HE) staining to observe the inflammatory cells infiltration and the thickening and narrowing of the pulmonary arterials. Results: Among 36 dogs, 2 dogs died within 24 hours after modeling, and 34 dogs were assigned to BAS+fenestrated ASD occulders group (n=12), BAS group (n=11), and non-septostomy group (n=11). Compared with BAS group, the average right atrial pressure (mRAP) and NT-proBNP of dogs in the BAS+fenestrated ASD occulders group were significantly reduced at 3 months after surgery (P<0.05), and the cardiac output (CO) was significantly increased at 6 months after surgery, arterial oxygen saturation (SaO2) was also significantly reduced (P<0.05). Compared with non-septostomy group, dogs in the BAS+fenestrated ASD occulders group had significantly lower mRAP and NT-proBNP at 1, 3, and 6 months after surgery (P<0.05), and higher CO and lower SaO2 at 6 months after surgery (P<0.05). Compared with the non-septostomy group, the dogs in the BAS group had significantly lower mRAP and NT-proBNP at 1 month after surgery (P<0.05), and there was no significant difference on mRAP and NT-proBNP at 3 and 6 months after surgery (P>0.05). Echocardiography showed that there was a minimal right-to-left shunt in the atrial septum in the BAS group at 1 month after the surgery, and the ostomy was closed in all the dogs in the BAS group at 3 months after the surgery. There was still a clear right-to-left shunt in the dogs of BAS+fenestrated ASD occulders group. The shunt was well formed and satisfactory endothelialization was observed at 1, 3 and 6 months after surgery. The results of HE staining showed that the pulmonary arterials were significantly thickened, stenosis and collapse occurred in the non-septostomy group. Pulmonary microvascular stenosis and inflammatory cell infiltration in the pulmonary arterials were observed in the non-septostomy group. Pulmonary arterial histological results were comparable between BAS+fenestrated ASD occulders group and non-septostomy group at 6 months after surgery. Conclusions: The fenestrated ASD occulder has the advantage of maintaining the open fistula hole for a longer time compared with simple balloon dilation. The fenestrated ASD occulder can improve cardiac function, and it is safe and feasible to treat PAH in this animal model.

[Effect of neuregulin-1 on cardiac glucose metabolism in rats with experimental myocardial infarction].

Objective: To investigate the effect of neuregulin-1(NRG-1) on cardiac glucose metabolism in Sprague Dawley (SD) rats with experimental myocardial infarction (MI). Methods: Adult male SD rats were randomly divided into three groups: the sham-operated group, MI group, and MI+NRG1 group. The rat MI model was established via ligation of the left anterior descending coronary artery. Two weeks after operation, echocardiography was performed, MI rats with left ventricular ejection fraction (LVEF) between 0.3-0.5 were selected and randomly assigned to MI group and MI+NRG-1 group. Rats in MI+NRG-1 group were treated with recombinant human NRG-1ß (100 µg/kg) via tail vein at 2 weeks after operation (twice per week for 6 weeks); while rats in sham-operated group and MI group received equal volume of physiological saline. By the end of administration, echocardiography and small animal positron emission tomography (PET) were performed to detect cardiac function and myocardial glucose uptake. Myocardial morphology and collagen volume fraction, cardiomyocyte apoptosis and reactive oxygen species (ROS) production were evaluated by histopathologic analysis. Myocardial pyruvate dehydrogenase (PDH) and citrate synthase (CS) activity, as well as ATP production were detected by commercial kits. The mRNA and protein expression levels of NRG-1, p-ErbB4, and key factors involved in glucose metabolism (including Glut-4, HK2, PDK4, PDH, CS) were detected by quantitative real-time PCR (qRT-PCR) and Western blot assay, respectively. Results: With the MI model successfully established, the left ventricular ejection fraction(LVEF) and left ventricular shortening fraction(LVFS) were significantly lower in MI group and MI+NRG-1 group than that in sham group (both P<0.01), while there was no significant difference between MI group and MI+NRG-1 group(all P>0.05). After 6 weeks of NRG-1ß intervention, the LVEF and LVFS were significantly higher in MI+NRG-1 group than in MI group (both P<0.01). By the end of experiment, PET imaging showed that the mean standardized uptake value (SUVmean) were lower in MI+NRG-1 group than in the sham group (4.06±0.28 vs. 5.18±0.37, P<0.01), while significantly higher than that in MI group (4.06±0.28 vs.2.86±0.49, P<0.01). Histopathological analysis showed that compared with MI group, rats in MI+NRG-1 group exhibited significantly decreased left ventricle collagen volume fraction ((7.83±1.24) % vs. (18.31±3.58) %, P<0.01), cardiomyocyte apoptosis((37.98±4.26)% vs. (67.04±5.38)%, P<0.01), and DHE fluorescence intensity(0.057 28±0.007 06 vs. 0.076 94±0.008 46, P<0.01), indicating that NRG-1ß could reduce ROS production. PDH activity, CS activity, and ATP production were significantly higher in MI+NRG-1 group than in MI group (all P<0.05). qRT-PCR demonstrated an upregulated Glut-4, HK2 and CS, but downregulated PDK4 mRNA expression in MI+NRG-1 group compared with MI group (all P<0.01). Western blot assay showed significantly higher protein expression of NRG-1, p-ErbB4, Glut-4, HK2, PDH, CS in MI+NRG-1 group than in MI group (all P<0.01). Conclusion: NRG-1 could improve glucose uptake and utilization in myocardium by activating phosphorylation of myocardial ErbB4 receptor in MI rats, thus providing a therapeutic option for improving energy metabolism after MI.

[Impact of transcatheter aortic valve replacement on renal function in patients with severe aortic stenosis].

Objective: To explore the impact of transcatheter aortic valve replacement (TAVR) on renal function in patients with severe aortic stenosis. Methods: This is a single-center retrospective study. Consecutive patients with severe aortic valve stenosis and received TAVR in Zhongshan Hospital from December 2014 to December 2019 were included. The patients were divided into four groups according to the estimate glomerular filtration rate (eGFR) measured at one day before TAVR, namely eGFR>90 ml·min-1·1.73m-2 group, 6090 ml·min-1·1.73m-2 group, 60

[Hemodynamic response in cirrhotic patients with transjugular intrahepatic portosystemic shunt].

Objective: To discuss the effects of transjugular intrahepatic portosystemic shunt (TIPS) procedure on hemodynamics in cirrhotic patients. Methods: A total of 23 cirrhotic patients for TIPS insertion were enrolled from January 2018 to October 2018. Serum N-terminal pro-B-type natriuretic peptide (NT-proBNP), transthoracic echocardiography and non-invasive cardiac output measurement based on impedance cardiogram were carried out before and 24h, 1 month, 6 months after TIPS in order to observe cardiac function and hemodynamic changes after TIPS. Results: Significant increases in right atrial area [(17.2±4.0) cm(2) vs. (15.0±3.4) cm(2), P<0.05], right ventricular area [(15.1±3.8) cm(2) vs. (13.7±3.5) cm(2), P<0.05] and left ventricular volume [(97.4±21.5) ml vs. (91.1±22.7) ml, P<0.05] were observed 24 h after TIPS. These changes were accompanied with significant reduction in collapsible index of inferior vena cava [(20.7± 8.1)% vs. (28.6±11.3)%, P<0.01] and elevation in pulmonary arterial systolic pressure [(36.0±8.4) mmHg (1 mmHg=0.133 kPa) vs. (31.8±5.4) mmHg, P<0.01]. There also existed significantly elevated serum NT-proBNP [(551.2±325.1) ng/L vs. (124.2±94.4) ng/L, P<0.01], cardiac output [(5.82±0.96) L/min vs. (5.12±1.28) L/min, P<0.01], cardiac index [(3.47±0.64) L·min(-1)·m(-2) vs. (3.05±0.78) L·min(-1)·m(-2), P<0.01], early diastolic filling rate [(59.0±14.3)% vs. (54.5±11.0)%, P<0.05], and reduced systemic vascular resistance index (SVRi) [(1 798.4±357.3) dyne·s·cm(-5)·m(-2) vs. (2 195.7±508.7) dyne·s·cm(-5)·m(-2), P<0.01] 24 h after TIPS. At the end of 6-month follow-up, all these parameters, but not SVRi, returned towards baseline values. Moreover, peak early to late diastolic tissue velocity ratio at the level of lateral mitral annulus (E'/A') was significantly higher at the end of 6-month follow-up than that at baseline (1.06±0.32 vs. 0.90±0.45, P<0.05). Neither the right ventricular fractional area changes nor the left ventricular ejection fractions during the follow-up period were different from those at baseline (P>0.05). Conclusion: Cirrhotic patients who had no cardiovascular pathologies had adequate adaptation and good compensation ability to reach a new hemodynamic homeostasis for the increased volume load after TIPS insertion.

[Prognostic value of N-terminal B-type natriuretic peptide on all-cause mortality in heart failure patients with preserved ejection fraction].

Objective: To investigate the prognostic value of N-terminal B-type natriuretic peptide (NT-proBNP) on all-cause mortality in heart failure patients with preserved ejection fraction (HFpEF) at real world scenarios. Methods: Patients who met the diagnostic criteria of HFpEF in the China National Heart Failure Registration Study (CN-HF) were divided into death and survival groups. The demographic data, physical examination, results of the first echocardiography, laboratory results at admission, complications, drug use and clinical outcomes were obtained from CN-HF. The univariate Cox proportional hazard model was used to screen the variates that might predict prognosis, and then the covariates with statistical significance were included in the multivariate Cox regression model to analyze the predictive value of baseline NT-proBNP on all-cause death. Spearman correlation analysis was used to evaluate the relationship between NT-proBNP and estimated glomerular filtration rate (eGFR), so as to further explore the predictive value of the interaction between renal dysfunction and NT-proBNP on death. Since NT-proBNP did not obey the binary normal distribution, it was expressed by the natural logarithm of NT-proBNP (LnNT-proBNP). Results: A total of 1 846 HFpEF patients were enrolled in this study, with an average age of 71.5 years, 1 017 males(55.1%), median NT-proBNP 860 ng/L, and median eGFR 73.9 ml·min-1·1.73m-2. After a median follow-up of 34 months, 213 (11.5%) patients died. Patients in the death group were older, with higher NYHA classification Ⅲ-Ⅳ ratio, longer hospital stay, higher serum potassium and NT-proBNP level, prevalence of complications of diabetes mellitus, arrhythmia and atrial fibrillation, use of angiotensin receptor antagonist(ARB), mineralocorticoid receptor antagonists (MRA), diuretic and digoxin was significantly higher in death group than in survival group. Body mass index (BMI), diastolic blood pressure, left ventricular ejection fraction (LVEF), hemoglobin, serum cholesterol(TC), serum triglycerides (TG) and eGFR, and use of angiotensin converting enzyme inhibitors (ACEI), statins and aspirin were lower in death group than in survival group. Univariate Cox regression analysis showed that NT-proBNP was a predictor of all-cause death in HFpEF patients (HR=2.522, 95%CI 2.040-3.119, P<0.001). Multivariate Cox regression analysis showed that the elevated NT-proBNP remains as the independent predictor of all-cause death in patients with HFpEF (HR=1.230, 95%CI 1.049-1.442, P=0.011) after adjusting for age, BMI, diastolic blood pressure, LVEF, hemoglobin, serum potassium, serum sodium, TC, serum high-density lipoprotein cholesterol (HDL-C), TG, eGFR, atrial fibrillation, as well as the treatment of ACEI/ARB, MRA, diuretics and digoxin. Spearman correlation analysis showed that LnNT-proBNP was negatively correlated with eGFR (r=-0.361, P<0.001), but there was no interaction between NT-proBNP and renal dysfunction in predicting death in HFpEF patients (P>0.05). Conclusion: The elevated level of NT-proBNP at admission is an independent predictor of all-cause mortality in HFpEF patients.

[Safety and efficacy of transcatheter aortic valve replacement through transcarotid approach for patients with severe aortic valve stenosis].

Objective: To investigate the safety and efficacy of transcatheter aortic valve replacement(TAVR) through transcarotid approach for patients with severe aortic valve stenosis. Methods: The clinical data of 9 symptomatic severe aortic valve stenosis patients who had high or prohibitive risk for surgery and not suitable for TAVR through femoral artery access,and thus received TAVR through transcarotid approach in our hospital from November 2015 to February 2017 were retrospectively analyzed.The patients were followed up to observe the safety and efficacy of the procedure. Results: There were 4 male and 5 female patients in this cohort, and age was (75.7±8.7) years old. The Society of Thoracic Surgery (STS) scores were (7.9±1.6)%. All patients were treated by left carotid artery approach. One patient experienced valve dislodgement during the procedure and received surgery, and TAVR procedure was successful in the rest 8 patients. Two patients were implanted with permanent pacemaker because of third degree atrioventricular block during the procedure.One patient had cardiac arrest during the procedure and recovered after external chest compression.One patient developed severe carotid stenosis,and there was no clinical manifestation of nerve function deficit after the procedure. All patients were followed up at (30±3) days after the procedure, and there were no adverse events. The modified Rankin scale score was 0. Echocardiography examination showed that the tranvalvular mean gradient was reduced from (63.0±19.2)mmHg(1 mmHg=0.133 kPa) on baseline to (18.1±4.9)mmHg(P<0.001), 4 cases had mild paravalvular leakage, and there was no moderate or severe paravalvular leakage.The NYHA classes was significantly improved at 30 days when compared with before the procedure(2 cases class Ⅱ, 4 cases class Ⅲ,3 cases class Ⅳ before the procedure,and 5 cases classⅠ, 4 cases class Ⅱ after the procedure, P=0.006) , and left ventricular ejection fraction increased from (55.9±13.1)% to (60.4±10.0)% (P=0.030). Conclusion: Our initial experience indicates that transcarotid TAVR is safe and effective for patients with severe aortic valve stenosis.

[Safety and efficacy of rotational atherectomy in the interventional treatment of coronary chronic total occlusion lesions].

Objective: To investigate the safety and efficacy of rotational atherectomy in the interventional treatment of coronary chronic total occlusion lesions. Methods: In this retrospective study,a total of 31 consecutive patients with coronary chronic total occlusion(CTO) lesions underwent rotational atherectomy in our hospital from February 2004 to December 2016 were enrolled,and the clinical features were analyzed. Coronary atherectomy was performed if balloon failed to cross the CTO lesions or balloon could not be fully dilated in the CTO lesions after wire crossing. The definition of procedure success was defined as residual stenosis less than 20% after implantation of drug eluting stent and rotational atherectomy. After the procedure, the patients were followed up to observe major adverse cardiac and cerebral vascular events which including cardiogenic death, myocardial infarction, cerebrovascular accident, and target lesion revascularization. Results: The 1.25 mm diameter burr was firstly selected in 80.6% (25/31) patients,and 96.8%(30/31) patients used only 1 burr to complete the rotational atherectomy procedure. The complication rate was 9.8% (3/31) including 1 patient with coronary dissection and 3 patients with slow flow or no flow. There was 1 patent with both coronary dissection and slow flow. The procedure success rate was 96.8%(30/31). Interventional treatment related myocardial infarction occurred in 3 patients during hospitalization.The 30 patients with procedure success were followed up 36(11, 96) months. The incidence rate of major adverse cardiac and cerebral vascular events was 13.3% (4/30), of which the cardiogenic death rate was 3.3% (1/30), the myocardial infarction rate was 6.7% (2/30), cerebrovascular accident rate was 3.3%(1/30),and the target lesion revascularization rate was 6.7% (2/30). Conclusion: Rotational atherectomy is safe and effective in the interventional treatment of coronary CTO lesions.

[A large-scale, multicenter, retrospective study on efficacy of bivalirudin use during peri-percutaneous coronary intervention period for Chinese patients with coronary heart disease].

OBJECTIVE: To observe the efficacy and safety of bivalirudin use in Chinese patients with coronary heart disease (CHD) during the peri-percutaneous coronary intervention(PCI) period. METHODS: A total of 3 271 patients who underwent PCI and received periprocedural bivalirudin treatment between July 2013 and October 2015 from 88 centers of China were involved in this study. The primary outcome was 30-day net adverse clinical events (NACE a composite of major adverse cardiac or cerebral events (MACE, all-cause death, reinfarction, urgent target vessel revascularization, or stroke) or bleeding), the secondary outcome was stent thrombosis at 30 days. RESULTS: The mean age of enrolled patients was (65.12±12.44) years old, 27.4%(889/3 244) of them were female. Percent of stable coronary disease (SCD), non-ST segment elevation acute coronary syndrome (NSTE-ACS) and ST elevation myocardial infarction (STEMI) was 5.0%(162/3 248), 44.6%(1 450/3 248) and 50.4%(1 636/3 248) respectively. Radial access was performed in 89.5% (2 879/3 271) patients, and 9.7% (316/3 271) and 34.1% (1 115/3 271) patients also received ticagrelor and tirofiban medication. 69.3% (2 266/3 271) patients received post-procedural bivalirudin infusion, in which 46.3% (1 050/2 266) was treated at PCI-does, with a median duration of 2.5(1.0, 4.0) h. During the 30-day follow-up, NACE occurred in 3.45% (103/2 988) patients, the incidence of MACE, death was 2.17% (65/2 994) and 1.03% (31/3 017), respectively and bleeding events were recorded in 1.37% (41/2 996) patients. Four cases (0.13%) of stent thrombosis (3 acute stent thrombosis) were recorded. CONCLUSION: Peri-PCI Bivalirudin use is safe and related with low bleeding risk in Chinese CHD patients.

The therapeutic effect of rosuvastatin on cardiac remodelling from hypertrophy to fibrosis during the end-stage hypertension in rats.

End-stage hypertensive heart disease is an increasing cause of cardiac mortality. Therefore, the current study focused on the cardiac remodelling from hypertrophy to fibrosis in old-aged spontaneously hypertensive rats (SHRs), and explored the therapeutic effects of Rosuvastatin and its possible mechanism(s) of action. Spontaneously hypertensive rats at age 52 weeks were randomly divided into three groups, the first two to receive Rosuvastatin at a dose of 20 mg/kg/day and 40 mg/kg/day, respectively, and the third to receive placebo, which was to be compared with Wistar-Kyoto as controls. After 2-month treatment, SBP, heart to body weight ratio (HW/BW%) and echocardiographic features were evaluated, followed by haematoxylin and eosin and Masson trichrome staining in conjunction with qPCR of foetal gene expressions. Transferase-mediated dUTP nick-end labelling assay and immunofluorescent labelling for active caspase-3 were used to detect the apoptotic cardiomyocytes. Signaling pathways involved were examined by using western blot. Old-aged SHR developed end-stage hypertensive heart disease characterized by significant enhancement of HW/BW%, LVAWd and LVPWd, and decreased LVEF and LVFS, accompanied by cardiomyocytes enlargement and fibrosis along with activation of foetal gene programme. Cardiac apoptosis increased significantly during the transition process. Rosuvastatin reduced hypertrophy significantly via AT(1) Receptor-PKCß2/α-ERK-c-fos pathway; protected myocardium against apoptosis via Akt-FOXO1, Bcl-2 family and survivin pathways and consequently suppressed the caspase-3 activity. The present study revealed that old-aged SHRs developed cardiac remodelling from hypertrophy to fibrosis via cardiac apoptosis during the end stage of hypertensive heart disease. These pathological changes might be the consequence of activation of AT(1) Receptor-PKCß2/α-ERK-c-fos and AKT-FOXO1/Bcl-2/survivin/Caspase3 signaling. Rosuvastatin effectively attenuated the structural changes by reversing the signaling transductions involved.