Objective To investigate the characteristics,occurrence times and management of cardiac erosion after transcatheter closure of ASD,and to discuss the mechanism and predictive factor of erosion.Methods We analyzed all the cases who received transcatheter ASD closure from September 1997 to September 2016 in our hospital retrospectively.Results 9 cases (9/6903,0.13％) were reported to have cardiac erosion events after device closure ASD of including 2 cases of acute cardiac tamponade needed pericardiocentesis,2 cases of aorta-to right-atrial fistula needed transcatheter closure or operative repair and 5 cases of perforation of the anterior leaflet of mitral valve.1 case with MV anterior leaflet perforation presented with hemolysis and required surgical repair.Cardiac erosion events were found at average 52.9±68.3 days (1-180days) after the ASD closure.Conclusions Cardiac erosion is a rare but serious complication of device closure for ASD.Erosion events are mostly attributed to device over-sizing or deficient retro-aortic rims.It is important for a strict follow-up,early deduction and timely disposition when an erosion event is identified.occurring.

Objective: To synthesize a folic acid (FA)-modified pH-sensitive nanomicelle containing sorafenib (SF) and superparamagnetic iron oxide (SPIO), and to access its visibility in MRI and anti-cancer efficacy on hepatocellular carcinoma (HCC) in vitro. Methods: The copolymer FA-PEG-Pasp (DBA/DIP) of FA, poly(ethylene glycol), N,N-dibutylethylenediamine and N,N-diisopropylethylenediamine grafted poly (L-aspartic acid) were prepared. SF and SPIO were encapsulated inside the copolymer to synthesize the targeting micelle FA-PEG-PAsp (DBA/DIP)-SPIO/SF (FPASS). The folate-free micelle[PEG-PAsp (DBA/DIP)-SPIO/SF (PASS)] was used as nontargeting micelle. The physicochemical properties and drug release behavior of the micelles were analyzed. MRI of HepG2 cells incubated with FPASS and PASS with different Fe concentrations and Prussian blue staining of cells treated with the micelles (Fe concentration of 20 μg/ml) was performed to assess the drug delivery capability and imaging function of the micelles. For the FA competitive inhibition assay in these experiments, HepG2 cells were pre-treated with an excess amount of free FA prior to the incubation with FPASS. Cell viability, cell apoptosis, cell cycle and tube formation assays were conducted for evaluating the anti-HCC effects of the micelles. Comparison between groups was analyzed by one-way ANOVA, and multiple comparisons correction was performed by LSD test. Results: The diameters of FPASS and PASS were (102.3±5.2) nm and (107.1±5.7) nm, respectively; the δ potentials of them were (29.7±1.6) mV and (31.5±1.4) mV, respectively. The T₂ relaxivity of both the micelles was (5.2±0.4) ml·μg^-1·s^-1, which was much higher than that of water soluble Fe₃O₄ nanoparticles [(2.3±0.1) ml·μg^-1·s^-1; F=76.45, P<0.01]. SF released from the micelles was much faster at pH5.0 than at pH7.4, which indicated that the micelles had a pH-triggered drug release behavior. MRI of HepG2 cell samples revealed the signal intensity on T₂WI images and the T₂ value on T₂-map images decreased with the increasing Fe concentrations in the micelles. At the same Fe concentration (5, 10, 20 and 40 μg/ml), the cells of FPASS group exhibited a more significant decrease in T₂ signal intensity and T₂ value compared with those of PASS group or FA competitive inhibition group (F=8.69, 14.03, 27.27, 32.25 and 19.80, 45.76, 113.20, 66.80; P<0.01). Prussian blue staining verified the existing of SPIO in the cytoplasm of cells. Compared with PASS, FPASS presented significantly higher anticancer effects on inducing apoptosis, causing G0/G1 phase arrest on HepG2 cells and inhibiting tube formation on human umbilical vein endothelial cells (t=7.905, 4.399 and 3.454, respectively; P<0.01). Conclusions The pH-sensitive nanomicelle FPASS was successfully constructed. This micelle possessed a hypersensitive MRI-visible function and a targeting SF delivery capability which may contribute to a significant anti-HCC effect.