[Effects of control-releasing arsenic trioxide-eluting stent on intimal smooth muscle cells and type III collagen in canine coronary artery post-stent model].

OBJECTIVE: To study the safety and efficacy of control-releasing arsenic trioxide (As2O3)-eluting stent on intimal smooth muscle cells (SMC) and type III collagen (CIII) in canine coronary artery post-stent model. METHODS: Twenty-four experimental canines were equally divided into 4 groups, the three tested groups were deployed by stents with different dosage of As2O3 (1.6 microg/mm2, 2.4 microg/mm2 and 3.2 microg/mm2 in low, median and high dose groups, respectively) and coated with polybutyl methacrylate/nano silica and poly-lactide-coglycolide in mild oversizing (stent/vessel ratio of 1.3:1) in left anterior descending (LAD) or circumflex coronary arteries (LCX), while the control group only by simple coated stent without As2O3. The effect was assessed 4 weeks after stent implantation in terms of vascular histomorphology, and changes of SMC and C III expressions were detected using immunohistochemical analysis. RESULTS: Subintimal hemorrhage, medial/adventitial necrosis, thrombosis and inflammatory cell infiltration were not found and integral endothelium could be seen under screening electron microscopy in all groups. Positive expression of SMC and CIII in the tested groups, especial in the high dose As2O3 group, was more weaker than that in control group. Histo-morphological analysis showed that the neo-genetic intimal area and vascular stenosis were lower, but the mean luminal diameter was larger in the three tested groups than that in the control group (P < 0.01). Comparisons of various indices between tested groups treated by different doses of As2O3 showed that the difference between high/median dose vs. low dose was significant (P < 0.01), but that between high dose vs. median dose was insignificant (P > 0.05). CONCLUSION: Control-releasing As2O3-eluting stent shows a reliable and safe effect in preventing and treating post-stent restenosis by its dose-dependent inhibition on expressions of SMC and CIII to suppress the neo-genesis of intimal hyperplasia.

[Clinical and angiographic characteristics of left coronaroventricular microfistula].

OBJECTIVE: To investigate the clinical and angiographic characteristics of left coronaroventricular microfistula. METHODS: In his retrospective review, clinical, electrocardiogram, echocardiography and coronary angiography data were analyzed for patients with left coronaroventricular microfistula. RESULTS: Left coronaroventricular microfistula was identified in 9 out of 8300 patients underwent coronary angiographies from 1998 to 2008 in our center. Seven patients were female (77.8%) and the average age was 71.5 years. All 9 patients had presenting symptoms of chest distress or dyspnea, coronary artery disease was documented in 5 (55.6%), hypertension in 2 (22.2%), valve disease in 1 (11.1%)and cardiomyopathy in 1 (11.1%) patient. Microfistula originated from one single coronary artery was seen in 1 patient (11.1%), from two coronary arteries in 6 patients (66.7%), from three coronary arteries in 2 patients (22.2%). The diagonal artery was involved in all patients. The characteristic sign of microfistula from CAG was intracavitary staining. CONCLUSION: Microfistula between coronary arteries and left ventricle is a rare disease, often originates from two coronary vessels and diagonal artery is involved in most cases.

[Effect of zedoary turmeric oil-eluting stents for post-stenting restenosis prevention and treatment].

OBJECTIVE: To investigate the effect and safety of Zedoary Turmeric Oil (ZTO)-eluting stents for post-coronary stenting restenosis prevention and treatment in the experimental dogs. METHODS: Bare stents, stents coated with polybutyl methacrylate/Nano silica, and stents eluted with 100 microg ZTO were randomly deployed in canine anterior descending or circumflex coronary artery. Four weeks after stent implantation, the dogs were sacrificed and the vascular histomorphologic changes in the stenting segment analyzed. RESULTS: Thickened intima could be seen under light microscope in the bare or coated stents, but thinner in ZTO-duting stent, with no sub-intimal hemorrhage, medial or adventitial necrosis, wall adhesive thrombus, or infiltration of inflammatory cells. Scanning electric microscopy showed the intima was intact. Histomorphologic analysis showed that the thickness and area of neo-intima, and the lumen stenosis percent in artery stented with ZTO eluting stents were significantly lower than those stented with bare or coated stents (P <0.01), and thus the lumen cavity was expanded (P < 0.01), while no statistic significant difference between polymer and bare stents was found (P > 0.05). CONCLUSION: ZTO-eluting stent is available and safe, and it could significantly inhibit the growth of neo-intimal in canine coronary mode after stenting, showing a restenosis preventive and treatment effect.

[Electrocardiographic and angiographic characteristics of patients with acute solitary posterior myocardial infarction].

OBJECTIVE: To investigate electrocardiographic (ECG) and angiographic characteristics of patients with acute solitary posterior myocardial infarction. Patients complicated by inferior wall or right ventricular infarction were excluded. METHOD: ECG and angiographic changes in 11 patients with acute solitary posterior myocardial infarction admitted to our emergency room from 2001 to 2006 were analyzed. RESULTS: Besides typical ST segment elevation in V(7)-V(9) leads, other ECG manifestations in these patients included V(1)-V(2) R/S > or = 1 (9/11, 81.8%), 1 - 2 mm ST depression in V(1)-V(4) (5/11, 45.5%), 0.5 - 1.5 mm ST elevation in I, aVL leads (4/11, 36.4%) and 0.5 - 1.5 mm ST elevation in V(5)-V(6) leads (5/11, 45.5%). Coronary angiography showed that left circumflex artery (LCX) was the infarction related artery in all cases. The infarction area located before OM1 origination in 1 patient with a 95% pipe-like stenosis (1/11), after OM1 origination in 6 patients (6/11, 4 with total occlusion, 1 with sub-total occlusion and 1 with 90% long length stenosis), in OM1 in 4 patients (4/11, 2 with total occlusion, 1 with sub-total occlusion and 1 with 95% local stenosis). There were 3 patients (27.3%) with single vessel lesion, 4 patients (36.4%) combined with left anterior descending artery (LAD) lesion, 2 patients (18.2%) combined with right coronary artery (RCA) lesion and 2 patients (18.2%) combined with LAD and RCA lesions. CONCLUSIONS: Acute posterior myocardial infarction should be suspected with V(1)-V(2) R/S > or = 1 and V(1)-V(4) ST depression in standard 12 leads ECG. Besides symptoms and cardiac enzyme measurements, recording posterior leads electrocardiogram and performing coronary angiography will help to make the correct diagnosis.

[Effect of early and non-early controlled-release of arsenic-trioxide eluting stents on restenosis inhibition in a canine model].

OBJECTIVE: To observe the safety and efficacy of early or non-early controlled-release arsenic-trioxide (As(2)O(3))-eluting stents on reducing in-stent neointimal hyperplasia. METHODS: Bare stents, stents coated with polybutyl methacrylate/Nano silica (containing 200 microg of As(2)O(3) per stent or not), stents coated with polybutyl methacrylate/Nano silica inside (containing 200 microg of As(2)O(3) per stent or not) and poly-lactide-co-glycolide (PLGA) outside were deployed with mild oversizing in left anterior descending (LAD) and circumflex coronary arteries (LCX)of 30 canines (n = 6, 12 stents for each group). RESULTS: The mean injury scores were similar in all groups at 4 weeks post stents implantation while the mean neointimal thickness, neointimal area and degree of stenosis were significantly reduced and the lumen area significantly increased in canines receiving single coating stents containing As(2)O(3) compared with single or double coating stents and bare stents groups (all P < 0.01). These effects were further enhanced in canines implanted with double coating stents containing As(2)O(3) (all P < 0.01 vs. single coating stents containing As(2)O(3)). No intraintimal hemorrhage, medial and adventitial necrosis, aneurysm, thrombosis, inflammatory cells infiltration were observed in all stenting groups. CONCLUSIONS: Controlled-release As(2)O(3)-eluting stents resulted in a significant inhibition of neointimal hyperplasia in the canine coronary arteries 4 weeks after stents implantation and the effects is more significant with controlled-release of As(2)O(3) at non-early stage than that at early stage.

[Effects of controlled-release arsenic-trioxide-eluting stents on in-stent neointimal hyperplasia in coronary artery: experiment with dog model].

OBJECTIVE: To study the safety and efficacy of controlled-release arsenic-trioxide (As(2)O(3))-eluting stents to reduce in-stent neointimal hyperplasia in coronary artery. METHODS: As(2)O(3) was sprayed onto the stainless steel coated with polybutyl methacrylate/nano-silica and poly-lactide-co-glycolide so as to make the controlled-release As(2)O(3)-eluting stents with the As(2)O(3) concentrations of 0, 1.6, 2.4, and 3.2 microg/mm(2). Thirty adult dogs were randomly divided into 5 equal groups to undergo deployment of bare stent, coated stent, and As(2)O(3)-eluting stent of low dose (1.6 microg/mm(2)), medium dose (2.4, microg/mm(2)), and high dose (3.2 microg/mm(2)) into the left anterior descending artery or circumflex coronary artery respectively, and aspirin 250 mg/day was given 3 days before operation until 4 weeks after operation. Four weeks after the operation the dogs underwent angiography and then killed. The coronary artery, heart, liver, spleen, lung, kidney, and brain were taken out for pathological examination. RESULTS: The mean injury scores were similar in all groups. The values of mean neointimal thickness of the high-, medium-, and low-dose groups were (0.14 +/- 0.05) mm, (0.15 +/- 0.04) mm, and (0.27 +/- 0.03 mm) respectively, all significantly lower than those of the coated stent and bare stent groups [(0.39 +/- 0.06) mm and (0.33 +/- 0.02) mm respectively, all P < 0.01], with significant differences between the high and medium groups and low dose group (both P < 0.01). The neointimal areas of the high, medium, and low dose groups were (1.09 +/- 0.11) mm(2), (1.33 +/- 0.10) mm(2), and (1.93 +/- 0.29) mm(2) respectively, all significantly smaller than those of the coated stent and bare stent groups [(2.44 +/- 0.15) mm(2) and (2.40 +/- 0.32) mm(2), all P < 0.01] with significant differences between the high and medium groups and low dose group (both P < 0.01). The stenosis rates of the high, medium, and low dose groups were (19.54 +/- 3.59)%, (22.18 +/- 3.3)%, and (36.22 +/- 5.17)% respectively, all significantly lower than those of the coated stent and bare stent groups [(50.39 +/- 3.03)%, and (46.88 +/- 5.85)% respectively, all P < 0.01] with significant differences between the high and medium groups and low dose group (both P < 0.01). The luminal areas of the high, medium, and low dose groups were (5.14 +/- 0.55) mm(2), (4.97 +/- 0.38) mm(2), and (3.75 +/- 0.39) mm(2) respectively, all significantly larger than those of the coated stent and bare stent groups [(2.62 +/- 0.22) mm(2) and (3.10 +/- 0.66) mm(2) respectively, both P < 0.01] with significant differences between the high and medium groups and low dose group (both P < 0.01). Pathological examination did not find intraintimal hemorrhage, medial and adventitial necrosis, aneurysm, thrombosis, and inflammatory cell infiltration in all groups. CONCLUSION: Capable of inhibiting neointimal hyperplasia in the coronary arteries dose-dependently after implantation, controlled-release As(2)O(3)-eluting stents is safe and applicable in treating coronary diseases.