Perspective of delay in door-to-balloon time among Asian population

1 Introduction Effective and timely reperfusion of infarcted coronary artery is crucial to the treatment of patients with ST-segment elevation myocardial infarction(STEMI).[1,2]Current guidelines highly recommend that the door-to-balloon(D2B)time,as a quality metric of primary percutaneous coronary intervention(PCI)in patients with STEMI,should be≤90 min and preferably less than 60 min.[3,4]However,significant variations from guidelines exist in the real world practices at hospitals.

Unusual course of congenital complete heart block in an adult:A case report

BACKGROUND Congenital complete heart block(CCHB)with normal cardiac structure and negativity for anti-Ro/La antibody is rare.Additionally,CCHB is much less frequently diagnosed in adults,and its natural history in adults is less well known.CASE SUMMARY A 23-year-old woman was admitted to our hospital for frequent syncopal episodes.She had bradycardia at the age of 1 year but had never had impaired exercise capacity or a syncopal episode before admission.The possible diagnosis of acquired complete atrioventricular block was carefully ruled out,and then the diagnosis of CCHB was made.According to existing guidelines,permanent pacemaker implantation was recommended,but the patient declined.With regular follow-up for 28 years,the patient had an unusually good outcome without any invasive intervention or medicine.She had an uneventful pregnancy and led a normally active life without any symptoms of low cardiac output or syncopal recurrence.CONCLUSION This case implies that CCHB in adulthood may have good clinical outcomes and does not always require permanent pacemaker implantation.

Effect of Endothelial Microparticles Induced by Hypoxia on Migration and Angiogenesis of Human Umbilical Vein Endothelial Cells by Delivering MicroRNA-19b

Background: Microparticles (MPs) are small extracellular plasma membrane particles shed by activated and apoptotic cells, which are involved in the development of atherosclerosis. Our previous study found that microRNA (miR)-19b encapsulated within endothelial MPs (EMPs) may contribute to the upregulation of circulating miR-19b in unstable angina patients. Hypoxia is involved in atherosclerosis as a critical pathological stimulus. However, it still remains unclear whether the increase of miR-19b levels in EMPs is related to hypoxia and if the effect of miR-19b - wrapped within EMPs - stimulates hypoxia on vascular endothelial cells. This study aimed to explore the changes of miR-19b in EMPs induced by hypoxia as well as their effects on endothelial cells.Methods: Human umbilical vein endothelial cells (HUVECs) were culturedin vitro and arranged to harvest EMPs in two parts: the first part consisted of EMPcontrol and EMPhypoxia and the second part included EMPvehicle, EMPNC mimic, and EMPmiR-19b mimic. Cell migration was detected by scratch migration and transwell chamber migration. Angiogenesis was assessed by tube formation assays. Furthermore, we predicted the target gene of miR-19b by bioinformatics analysis, and luciferase assay was used to verify the targeted gene of miR-19b. Data were analyzed by one-way analysis of variance. Student’st-test was used when two groups were compared.Results: Compared with EMPcontrol- and EMPhypoxia-inhibited migration of cells by scratch migration assay (80.77 ± 1.10 vs. 28.37 ± 1.40,P < 0. 001) and transwell chamber migration assay (83.00 ± 3.46 vs. 235.00 ± 16.52,P < 0.01), the number of tube formations was markedly reduced by 70% in the EMPhypoxia group (P < 0.001)in vitro analysis of HUVECs. Meanwhile, a strong inhibition of migration and tube formation of HUVECs in the presence of miR-19b-enriched EMPmiR-19b mimic was observed. This effect might be due to the delivery of miR-19b in EMPs. Transforming growth factor-β2 (TGFβ2) was predicted to be one of the target genes of miR-19b, and we further confirmed thatTGFβ2 was a direct target gene of miR-19b using the luciferase assay. The expression ofTGFβ2 in HUVECs was inhibited by treatment with EMPhypoxia and EMPmiR-19b mimic .Conclusions: MiR-19b in EMPs induced by hypoxia could reduce endothelial cell migration and angiogenesis by downregulating TGFβ2 expression, which may have inhibited the progression of atherosclerosis.