Vessel healings after stenting with different polymers in STEMI patients

Background Different stents implantation in ST-segment elevation myocardial infarction (STEMI) patients may influence the long term prognosis by affecting vessel healings after stenting. The aim of this study was to evaluate the vessel healings after implantation of drug eluting stents (DES) with biodegradable or durable polymer or of bare-metal stents (BMS) in patients with acute STEMI. Methods This study included 50 patients, who underwent follow up angiogram and optical coherence tomography (OCT) assessment about one year after percutaneous coronary intervention (PCI) for STEMI. According to the initial stents types, these patients were classified to durable (n = 19) or biodegradable polymer sirolimus-eluting stents (n = 15), or BMS (n = 16) groups. The conditions of stent struts coverage and malapposition were analyzed with OCT technique. Results A total of 9003 struts were analyzed: 3299, 3202 and 2502 from durable or biodegradable polymer DES, or BMS, respectively. Strut coverage rate (89.0%, 94.9% and 99.3%, respectively), malapposition presence (1.7%, 0.03% and 0 of struts, respectively) and average intimal thickness over struts (76 ± 12 μm, 161 ± 30 μm and 292 ± 29 μm, respectively) were significantly different among different stent groups (all P < 0.001). Conclusions Vessel healing status in STEMI patients is superior after implantation of biodegradable polymer DES than durable polymer DES, while both are inferior to BMS     

Experiment Study Of The Preventive Effects Of Valsartan Eluting Stent On In- stent Restenosis

Objectives Background -Neointima hyperplasia and arterial remodeling are the main mechanisms of restenosis after percutaneous transluminal coronary angioplasty. The successful use of coronary stents neutralizes the acute elastic recoil and improves the remodeling mode with reducing restenosis rate by 10 % . But the in - stent neointima hyperplasia becomes more severe. This study aims to set up model of in - stent restenosis in vivo, and to e-valuate the preventive role of implantation of valsartan eluting stent for restenosis. Methods and Results Twenty - two male New Zealand white rabbits were divided into control group and valsartan group. In-travascular ultrasonic (IVUS) results showed the in-trastent neointimal areas of the control group were larger than those of the valsartan group (P < 0. 01) . The minimal lumen area of control group was smaller than that of the valsartan group ( P < 0. 01). Angiog-raphy results showed the normal lumen diameters were similar between two groups ( P> 0.05) . The lum     

Prevalence of celiac disease in Germany:A prospective follow-up study

AIM:To determine the prevalence of celiac disease in a randomly selected population sample. METHODS:A total of 2157 subjects (1036 males; 1121 females) participating in a population-based cross-sectional study underwent laboratory testing for tissue transglutaminase and antibodies to immunoglobulin A, endomysium and antigliadin. In a second step, all subjects who had been examined serologically were surveyed using a questionnaire that included questions specific to celiac disease. Subjects with positive antibody titers and those with histories positive for celiac disease then underwent biopsy. At the first follow up, antibody titers were again determined in these subjects and subjects were questioned regarding symptoms specific for celiac disease and disorders associated with celiac disease. The second follow up consisted of a telephone interview with subjects positive for celiac disease.RESULTS:Antibody tests consistent with celiac disease were reported in eight subjects, corresponding to an overall prevalence of 1:270 (8/2157). The prevalence among women was 1:224 and 1:518 in men. Classical symptoms were observed in 62.5% of subjects. Atypical celiac disease was present in 25.0%, and transient celiac disease in 12.5%. False-negative test results were returned in three subjects. This yields a sensitivity and specificity of 62.5% and 50.0%, respectively, for tissue transglutaminase immunoglobulin-A antibody; of 62.5% and 71.4% respectively, for endomysium antibody; and of 62.5% and 71.4%, respectively, for antigliadin antibody.CONCLUSION:The prevalence rate in our collective lies within the middle tertile of comparable studies in Europe. The use of a single antibody test for screening purposes must be called into question.     

Endoscopic resection using band ligation for esophageal SMT in less than 10mm

AIM:To evaluate the safety and feasibility of endoscopic resection using band ligation(EMR-B) for the diagnostic and therapeutic removal of tumors located in the esophageal subepithelial region having originated from the submucosa.METHODS:From May 2009 to September 2014,after medical chart and endoscopic ultrasonography report review,a total of 15 esophageal tumors located in the submucosal layer were resected by EMR-B.Previous symptom,location,pathology,complete resection rate,incidence of complications,incidence of minor complication,size,length of procedures time and follow up months were evaluated.To evaluate local recurrence at the resection site,periodic follow-up endoscopic examination was undertaken in all of the patients.The first endoscopic examination was performed about 6 mo after the endoscopic resection.Thereafter,the endoscopic follow up were scheduled annually.RESULTS:The mean age was 50.3 ± 9.67 years.The mean tumor size was 6.93 ± 3.15 mm and most of the lesions size was between 5-10 mm in diameter(10/15,66.6%).In all patients,endoscopic en bloc resection was achieved.In one patient,the vertical margin was involved.The mean procedural time was 8.86 ± 3.66 min.In all patients,no evidence of severe complications such as perforation or bleeding occurred.Minor complications such as chest pain(2/15,13.3%) and heartburn(3/15,13.3%) were reported but they symptoms were controlled by proton pump inhibitors,ulcermin and/or analgesics.Histologic assessments of the removed specimens revealed 10 granular cell tumors(66.6%),4 leiomyomas(16.6%) and one lipoma(6.6%).No recurrence was observed during the mean follow up period of 45 ± 3.5 mo(range:5-64 mo).CONCLUSION:EMR-B might be considered safe and effective for the diagnosis and treatment of lesions measuring less than 10 mm in diameter.     

Selection and evaluation of three interventional procedures for achalasia based on long-term follow-up

AIM: To determine the best method out of the three types of interventional procedure for achalasia based on a longterm follow-up.METHODS: The study cohort was comprised of 133 patients of achalasia. Among them, 60 patients were treated under fluoroscopy with pneumatic dilation (group A), 8 patients with permanent uncovered or antireflux covered metal stent dilation (group B), and 65 patients with temporary partially covered metal stent dilation (group C).RESULTS: One hundred and thirty dilations were performed on the 60 patients of group A (mean 2.2 times per case).The mean diameter of the strictured cardia was 3.3±2.1 mm before dilation and 10.6±3.8 mm after dilation. The mean dysphagia score was 2.7±1.4 before dilation and 0.9±0.3after dilation. Complications in group A were chest pain (n=30), reflux (n=16), and bleeding (n=6). Thirty-six patients (60 %) in group A exhibited dysphagia relapse during a 12-month follow-up, and 45 patients (90 %) out of 50 exhibited dysphagia relapse during a 36-month followup. Five uncovered and 3 antireflux covered expandable metal stents were permanently placed in the 8 patients of group B. The mean diameter of the strictured cardia was 3.4±1.9 mm before dilation and 19.5±1.1 mm after dilation.The mean dysphagia score was 2.6±1.3 before dilation and 0.4±0.1 after dilation. Complications in group B were chest pain (n=6), reflux (n＝5), bleeding (n=3), and hyperplasia of granulation tissue (n=3). Four patients (50 %) in group B exhibited dysphagia relapse during a 12-month followup, and 2 case (66.7 %) out of 3 patients exhibited dysphagia relapse during a 36-month follow-up. Sixty-five partially covered expandable metal stents were temporarily placed in the 65 patients of group C and withdrawn after 3-7 days via gastroscopy. The mean diameter of the strictured cardia was 3.3±2.3 mm before dilation and 18.9±3.5 mm after dilation. The mean dysphagia score was 2.4±1.3 before dilation and 0.5±0.2 after dilation. Complications in group C were chest pain (n=26), reflux (n=13), and bleeding (n=8).6 patients (9.2 %) out of 65 exhibited dysphagia relapse during a 12-month follow-up, and 8 patients (14.5 %) out of 55 exhibited dysphagia relapse during a 36-month followup. All the stents were inserted and withdrawn successfully.The follow-up in groups A-C lasted 12-96 months.CONCLUSION: Temporary partially covered metal stent dilation is one of the best methods with interventional procedure for achalasia in terms of long-term follow-up.     

Solid-pseudopapillary tumor of the pancreas： Clinical experience and literature review

AIM: To evaluate the clinical presentations of solid-pseudopapillary tumor of the pancreas (SPT) and examine the diagnosis, treatment, low grade malignant potential of this rare disease. METHODS: We retrospectively reviewed a series of seven patients with SPT managed in our hospital between July 1990 and October 2003. Six females and one male with mean age of 31 years (range 13 to 50 years) were diagnosed with SPT at our institution. RESULTS: Clinical presentation included a palpable abdominal mass in two patients and vague abdominal discomfort in another two. Two patients were asymptomatic; their tumors were found incidentally on abdominal sonographic examination for other reasons. The final patient was admitted with hemoperitoneum secondary to tumor rupture. The mean diameter of the tumors in the seven patients was 10.5 cm (range 5 to 20 cm). The lesions were located in the body and tail in five cases and in the head of the pancreas in two. Surgical procedures included distal pancreatectomy (3), distal pancreatectomy with splenectomy (2), pancreaticoduodenectomy (1) and a pylorus-preserving Whipple procedure (1). There were gross adhesions or histological evidence of infiltration to the adjacent pancreas and/or splenic capsule in four cases. None of the patients received adjuvant therapy. The mean follow up was 7 years (range 0.5 to 14 years). One patient developed multiple liver metastases after 14 years of follow up. CONCLUSION: SPT is a rare tumor that behaves less aggressively than other pancreatic tumor. However, in cases with local invasion, long-term follow up is advisable.     

Strut thickness effect on restenosis of Multi-Link and Tri-Star stenting

Background Increased thrombegenicity and smooth muscle cell proliferative response induced by the metal struts compromise the advantages of coronary stenting. Adnan Kastrati et al. reported in the ISAR-STEREO trial that a reduced strut thickness of coronary stent is associated with improved follow up angiographic and clincal results.     

Comparison between uncovered and covered self-expandable metal stent placement in malignant duodenal obstruction

AIM:To compare the clinical outcomes of uncovered and covered self-expandable metal stent placements in patients with malignant duodenal obstruction.METHODS:A total of 67 patients were retrospectivelyenrolled from January 2003 to June 2013.All patients had symptomatic obstruction characterized by nausea,vomiting,reduced oral intake,and weight loss.The exclusion criteria included asymptomatic duodenal obstruction,perforation or peritonitis,concomitant small bowel obstruction,or duodenal obstruction caused by benign strictures.The technical and clinical success rate,complication rate,and stent patency were compared according to the placement of uncovered(n = 38) or covered(n = 29) stents.RESULTS:The technical and clinical success rates did not differ between the uncovered and covered stent groups(100% vs 96.6% and 89.5% vs 82.8%).There were no differences in the overall complication rates between the uncovered and covered stent groups(31.6% vs 41.4%).However,stent migration occurred more frequently with covered than uncovered stents [20.7%(6/29) vs 0%(0/38),P < 0.05].Moreover,the overall cumulative median duration of stent patency was longer in uncovered than in covered stents [251 d(95%CI:149.8 d-352.2 d) vs 139 d(95%CI:45.5 d-232.5 d),P < 0.05 by log-rank test] The overall cumulative median survival period was not different between the uncovered stent(70 d) and covered stent groups(60 d).CONCLUSION:Uncovered stents may be preferable in malignant duodenal obstruction because of their greater resistance to stent migration and longer stent patency than covered stents.     

Endosonography with linear array instead of endoscopic retrograde cholangiography as the diagnostic tool in patients with moderate suspicion of common bile duct stones

AIM: To evaluate the diagnostic efficiency of endoscopic ultrasound (EUS) as the main imaging modality in patients with moderate suspicion of common bile duct stones (CBDS).METHODS: 55 patients with moderate clinical suspicion of CBDS were prospectively included to the study and evaluated with EUS. This study was done in single blind method in the clinical and biochemical data of patients. EUS was done with echo-endoscope Pentax FG 32-UA (f=5-7,5 MHz) and Hitachi EUB 405 ultrasound machine. Patients diagnosed with CBDS by EUS were excluded from this study and treated with ERC. All the other patients were included to the follow up study obtained by mail every 6 months for clinical evaluation(need of ERC or surgery).RESULTS: CBDS was found in 4 patients by EUS. Diagnosis was confirmed in all cases on ERC. The remaining 51 patients without CBDS on EUS were followed up for 6-26 months(meanly 13 months) There were: 40 women, 42 cholecystectomized patients, aged: 55 (mean). Biochemical values (mean values) were as follows: bilirubin: 14,9 μmol.L^-1,alkaline phosphatase: 95 IU&#183;L^-1, γ-GTP: 131 IU&#183;L^-1, ALT: 50IU&#183;L^-1, AST: 49 IU&#183;L^-1. Only 1 patient was lost for follow up.In the remaining 50 patients with follow up, there was only1 (2 %) patient with persistent biliary symptoms in whom CBDS was finally diagnosed by ERC with ES. All other patients remained symptoms free on follow up and did not require ERC or biliary surgery.CONCLUSION: Vast majority of patients with moderate suspicion of CBDS and no stones on EUS with linear array can avoid invasive evaluation of biliary tree with ERC.     

Radiation risks associated with serial imaging in colorectal cancer patients: Should we worry?

To provide an overview of the radiation related cancer risk associated with multiple computed tomographic scans required for follow up in colorectal cancer patients.A literature search of the PubMed and Cochrane Library databases was carried out and limited to the last 10 years from December 2012.Inclusion criteria were studies where computed tomographic scans or radiation from other medical imaging modalities were used and the risks associated with ionizing radiation reported.Thirty-six studies were included for appraisal with no randomized controlled trials.Thirty-four of the thirty-six studies showed a positive association between medical imaging radiation and increased risk of cancer.The radiation dose absorbed and cancer risk was greater in children and young adults than in older patients.Most studies included in the review used a linear,nothreshold model to calculate cancer risks and this may not be applicable at low radiation doses.Many studies are retrospective and ensuring complete follow up on thousands of patients is difficult.There was a minor increased risk of cancer from ionizing radiation in medical imaging studies.The radiation risks of low dose exposure(<50 milli-Sieverts)are uncertain.A clinically justified scan in the context of colorectal cancer is likely to provide more benefits than harm but current guidelines for patient follow up will need to be revised to accommodate a more aggressive approach to treating metastatic disease.     

采用光学相干断层成像技术评价国产雷帕霉素洗脱支架术内膜覆盖情况

Objective:Confirming complete neointimal coverage after implantation of drug-eluting stent(DES)is clinically important because incomplete stent coverage is maybe responsible for late thrombosis and sudden cardiac death.Optical coherence tomography(OCT)is a high-resolution(≈10 μm)imaging technique capable of detecting a thin layer of neointimal hyperplasia(NIH)inside DES.Helios stent system(KinheIy Bio-tech Co(Shenzhen).Ltd)is a new generation of sirolimus eluting stents.Methods:Motorized optical coherence t...     

光学相干断层成像评价药物洗脱支架置入术后晚期支架贴壁不良

目的 探讨药物洗脱支架(DES)置入术后晚期支架贴壁不良的特点.方法 分析32例(包括51支血管、共置入71个支架)置入DES 1年后[(14.8±5.2)个月]行光学相干断层成像(OCT)检查的患者资料,对支架节段的OCT图像每间隔0.5 mm取1帧图像进行分析,找出贴壁不良的支架金属结构,测量支架到参照血管内壁的距离及支架表面内膜厚度,分析晚期支架贴壁不良的特点.结果 OCT检查在7例(21.9%)患者中检出支架贴壁不良,其中4例合并支架段血管的正性重构,1例重叠置入支架,2例发现由血栓覆盖支架金属结构,7例患者随访期间无心脏不良事件发生.97.6%的支架金属结构完全贴壁并不同程度的内膜覆盖,2.4%的支架金属结构贴壁不良,包括1.2%的支架金属结构位于血管分支开口.位于血管分支开口的支架金属结构与其他贴壁不良支架表面的内膜覆盖厚度差异无统计学意义[(0.06±0.05)mm比(0.05±0.03)mm,P>0.05].绪论晚期支架贴壁不良见于DES置入最初的贴壁不良、血管壁正性重构、重叠置入支架以及支架金属结构位于分支血管开口;贴壁不良的支架金属结构表面亦有不同程度的内膜覆盖.     

First-in-Man Evaluation of a Sirolimus-Eluting Stent With Abluminal Fluoropolymeric/Triflusal Coating With Ultrathin Struts by OCT at 9 Months' Follow-Up: The PROMETHEUS Study

ObjectivesWe sought to investigate stent healing and neointimal hyperplasia with ihtDEStiny drug-eluting stent (DES) by optical coherence tomography (OCT) examination conducted 9 months after implantation.BackgroundThe currently used DES present certain features that have been linked separately to their better performance in terms of efficacy and safety.MethodsFirst-in-man, prospective and multicenter study including patients treated with ihtDEStiny stent undergoing OCT examination at 9 months follow up. The ihtDEStiny stent is a sirolimus eluting stent with an oval shape ultrathin struts (68 μm) and an abluminal coating of a fluoropolymer containing the antiplatelet agent triflusal. Primary endpoint was the percentage of obstruction of the in-stent volume by the neointima.ResultsIn 58 patients (63 lesions) in-stent late lumen loss was 0.11 ± 0.23 mm (95% CI 0.05–0.16) with only in 6% of stents being > 0.5 mm and in-segment binary stenosis was 1.6%. In OCT mean neointima volume obstruction was 10.5 ± 6.9% with a mean neointima thickness of 110.9 ± 89.8 μm. The proportion of uncovered struts was 2.5%, malapposed struts 1.1% and malapposed/uncovered struts 0.7% and no subclinical thrombi detected. Mean incomplete stent apposition area was 0.1 ± 0.1 mm². At 12 months target lesion revascularization rate was 3% and no stent thrombosis was reported.ConclusionsIn this study the ihtDEStiny stent has shown a very low degree of neointimal proliferation associated with a low rate of uncovered/malapposed struts and total absence of subclinical thrombi at 9 months follow up.     

Neointimal coverage of sirolimus-eluting stents at 6-month follow-up: evaluated by optical coherence tomography.

AIMS: Since the intravascular ultrasound (IVUS) cannot detect neointimal layers in the majority of sirolimus-eluting stents (SES) at the chronic phase, it is still controversial to what extent SES remain uncovered. However, optical coherence tomography (OCT) with excellent resolution may be able to detect thinner neointima. METHODS AND RESULTS: A total of 34 patients (57 SES) underwent OCT and IVUS evaluations at 6-month follow-up. The thickness of neointima on each SES strut cross-section and strut apposition to the vessel wall was evaluated. By OCT evaluation, the median (25th, 75th percentiles) neointima thickness was 52.5 microm (28.0 microm, 147.6 microm) and the prevalence of struts covered by thin neointima undetectable by IVUS was 64%. The average rate of neointima-covered struts in an individual SES was 89%. Nine SES (16%) showed full coverage by neointima, whereas the remaining stents had partially uncovered strut lesions. Among the 6840 struts visualized by OCT in all of the SES, 79 struts showed malapposition without neointimal coverage, and were frequently observed in the areas of SES overlap. CONCLUSION: At 6 months, most of the SES were covered with thin neointima, but few showed full coverage.     

Relationship between stent malapposition and incomplete neointimal coverage after drug-eluting stent implantation

Background: Using optical coherence tomography (OCT), we evaluated the relationship between malapposed and uncovered struts following implantation of drug‐eluting stents (DESs). Methods: A total of 271 patients with 306 lesions who underwent DES implantation and follow‐up OCT were included in the study. The lesions were grouped based on the presence of malapposition and then by the median value of the percentage of malapposed struts (1.3%) to produce 3 groups: lesions without malapposition (group I, n = 232) and those with percentage of malapposed struts <1.3% (group II, n = 37) or ≥1.3% (group III, n = 37). Percentages of malapposed and uncovered struts were calculated as percent ratio of malapposed or uncovered to total struts in the defined cross‐sections, respectively. We compared percentage of uncovered struts in all analyzable struts and in the residual struts without malapposed segments among the 3 groups. Results: Group III showed a significantly larger percentage of uncovered struts among all the struts (group I, 3.7 ± 6.4 vs. II, 5.5 ± 5.6 vs. III, 17.6 ± 15.9%, P < 0.001) and among residual struts without malapposed segments (3.7 ± 6.4 vs. 5.2 ± 5.7 vs. 15.0 ± 14.4%, respectively, P < 0.001). There was a significant correlation between malapposed and uncovered struts in group III (r = 0.393, P = 0.016), but not in group II (r =?0.007, P = 0.965) among residual struts without malapposed segments. Conclusion: The percentage of uncovered DES struts was quite different depending on the presence and extent of malapposed struts. (J Interven Cardiol 2012;25:270–277)     

Evaluation by optical coherence tomography of neointimal coverage of sirolimus-eluting stent three months after implantation

Confirming complete neointimal coverage after implantation of a drug-eluting stent is clinically important because incomplete stent coverage is responsible for late thrombosis and sudden cardiac death. Optical coherence tomography is a high-resolution (approximately 10 microm) imaging technique capable of detecting a thin layer of neointimal hyperplasia (NIH) inside a sirolimus-eluting stent (SES) and stent malapposition. This investigation evaluated stent exposure and malapposition 3 months after SES implantation using optical coherence tomography in a different clinical presentations, such as acute coronary syndrome (ACS) and non-ACS. Motorized optical coherence tomographic pullback (1 mm/s) was performed at 3-month follow-up to examine consecutive implanted 31 SESs in 21 lesions in 21 patients (9 with ACS and 12 with non-ACS). NIH thickness inside each strut and percent NIH area in each cross section were measured. In total, 4,516 struts in 567-mm single-stented segments were analyzed. Overall, NIH thickness and percent NIH area were 29 +/- 41 microm and 10 +/- 4%, respectively. Rates of exposed struts and exposed struts with malapposition were 15% and 6%, respectively. These were more frequent in patients with ACS than in those with non-ACS (18% vs 13%, p <0.0001; 8% vs 5%, p <0.005, respectively). In conclusion, neointimal coverage over a SES at 3-month follow-up is incomplete in ACS and non-ACS. Our study suggests that dual antiplatelet therapy might be continued >3 months after SES implantation.     

Preliminary observations using optical coherence tomography to assess neointimal coverage of a metal stent in a porcine model

BackgroundConcerns surrounding late stent thrombosis have prompted the development of novel imaging techniques to assess neointimal coverage. Recent clinical studies have evaluated optical coherence tomography (OCT) to evaluate neointimal coverage, but pathologic correlation in an animal model is lacking. We assessed the hypothesis that OCT could accurately assess early neointimal coverage in a porcine model.MethodsOCT imaging of bare metal stents in each coronary artery was performed at implantation (n=6), Day 4 (n=3), and Day 20 (n=3), and images were evaluated at three cross-sections per stented segment. Neointimal strut coverage was categorized by OCT as covered or uncovered, and neointimal thickness was determined (Day 20). Pathological correlation was obtained using scanning electron microscopy (SEM) to assess strut coverage (Day 4) and histomorphometry to quantify neointimal thickness (Day 20).ResultsAt Day 4, OCT imaging detected 28 (26%) of 109 uncovered struts, and the ratio of uncovered/total strut area by SEM was 31%. All imaging modalities showed complete coverage at Day 20. Mean (±SE) neointimal thickness at Day 20 was 109±6 μm by OCT (n=116 struts) and 93±5 μm by pathology (n=68). Mean neointimal thickness on a segment-by-segment basis determined by OCT correlated with mean histomorphometric analysis (Reviewer 1: r=.74, P=.092 and Reviewer 2: r=0.60, P=.212).ConclusionsDay 4 represents an important time point for the assessment of early neointimal coverage in the porcine model. OCT imaging accurately assesses the extent and thickness of early neointimal coverage with good pathologic correlation. OCT represents a promising imaging modality for the in vivo assessment of neointimal coverage.     

Neointimal coverage and late apposition of everolimus-eluting bioresorbable scaffolds implanted in the acute phase of myocardial infarction: OCT data from the PRAGUE-19 study

Incomplete stent apposition and uncovered struts are associated with a higher risk of stent thrombosis. No data exist on the process of neointimal coverage and late apposition status of the bioresorbable vascular scaffold (BVS) when implanted in the highly thrombogenic setting of ST-segment elevation acute myocardial infarction (STEMI). The aim of this study was to assess the serial changes in strut apposition and early neointimal coverage of the BVS using optical coherence tomography (OCT) in selected patients enrolled in the PRAGUE-19 study. Intracoronary OCT was performed in 50 patients at the end of primary percutaneous coronary intervention for acute STEMI. Repeated OCT of the implanted BVS was performed in 10 patients. Scaffold area, scaffold mean diameter and incomplete strut apposition (ISA) were compared between baseline and control OCT. Furthermore, strut neointimal coverage was assessed during the control OCT. Mean scaffold area and diameter did not change between the baseline and control OCT (8.59 vs. 9.06 mm²; p = 0.129 and 3.31 vs. 3.37 mm; p = 0.202, respectively). Differences were observed in ISA between the baseline and control OCT (0.63 vs. 1.47 %; p < 0.05). We observed 83.1 % covered struts in eight patients in whom the control OCT was performed 4–6 weeks after BVS implantation, and 100 % covered struts in two patients 6 months after BVS implantation. Persistent strut apposition and early neointimal coverage were observed after biodegradable vascular scaffold implantation in patients with acute ST-segment elevation myocardial infarction.     

Persistent malapposition after implantation of sirolimus-eluting stent into intramural coronary hematoma: optical coherence tomography observations.

A 76-year-old man presented with an anterior myocardial infarction. Coronary angiography showed 99% stenosis in the left anterior descending artery and total occlusion in the left circumflex artery (LCX). After successful percutaneus coronary intervention (PCI) for segment 7, a staged PCI to the LCX with a distal protection system was attempted, but the wire entered the subintima, creating a large dissection and intramural hematoma. Three sirolimus-eluting stents (SES) were implanted to cover the entire hematoma, but 2 weeks later intravascular ultrasound revealed stent malapposition, with healing of the residual hematoma, and vessel enlargement. Optical coherence tomography (OCT) showed the malapposition more clearly. Balloon dilatation successfully achieved apposition of the SES to the vessel wall, but 6 months later it revealed recurrence of malapposition, with the struts covered by thrombus-like tissue. This case suggests that SES implantation treatment of a long intramural hematoma can potentially cause late malapposition because of persistent vessel enlargement related to arterial wall injury and inhibition of neointimal hyperplasia by the SES. OCT is useful in showing the precise condition of the stent struts.     

Neointimal coverage and stent strut apposition six months after implantation of a paclitaxel eluting stent in acute coronary syndromes: An optical coherence tomography study

Objectives

Prospective optical coherence tomography (OCT) study of strut apposition and neointimal hyperplasia thickness (NIH) of a paclitaxel eluting stent (PES), (Infinium, Sahajanand Medical Technologies Pvt Ltd.).

Background

Few data exist concerning neointimal coverage of PES. Uncovered and malapposed struts are more common following stenting in acute coronary syndromes (ACS) than in non-ACS lesions.

Methods

All consecutive patients with ACS, treated with the above PES for single native coronary lesions between August 2008 and January 2009, who consented to invasive follow-up with OCT at six months (N = 13), were included.

Results

At 6 months no patient demonstrated angiographic restenosis. 3180 struts from 20 stents were analyzed, and 91.3% were covered with neointima (NIH 204.8 ± 159.5 μm). Standard statistics and least squares estimates (LSE) derived from a hierarchical ANCOVA model to take into account clustering effects are presented. Rate of uncovered struts was 8.6%, LSE 7.39 (95% CI 3.05-11.73), malapposed struts 2.2%, LSE 1.76 (95% CI 0.05-3.58), and protruding struts 2.9%, LSE 2.8 (95% CI 1.35-4.65). The proportion of uncovered malapposed struts was significantly higher compared to uncovered embedded struts (55.7% vs. 6.8%, p < 0.01). In total, 5 (25%) PES were fully covered by neointima. No intracoronary thrombus or clinical events were detected.

Conclusions

Six months after implantation of a specific PES in patients with ACS, most of the stents were only partially covered with neointima, especially at sites of strut malapposition or protrusion. These findings emphasize the need for optimal stent apposition during implantation and for prolonged dual antiplatelet therapy.