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91.

Objectives

The aim of this study was to investigate clinical outcomes after left main coronary artery (LM) bifurcation percutaneous coronary intervention (PCI) and the impact of the duration of dual antiplatelet therapy (DAPT) according to treatment strategy.

Background

There are limited data regarding the optimal PCI strategy for LM bifurcation lesions with new-generation drug-eluting stents.

Methods

A patient-level pooled analysis of 5 nationwide multicenter registries was performed. Rates of target lesion failure, thrombotic adverse cardiovascular events, and their individual components at 3-year were analyzed. Subgroup analysis according to DAPT duration was performed.

Results

From 13,172 patients undergoing PCI with new-generation drug-eluting stents, a total of 700 patients were treated for LM bifurcation lesions, 567 with a 1-stent strategy and 133 with a 2-stent strategy. Rates of target lesion failure and target lesion revascularization were higher in the 2-stent group, driven mainly by complex lesion profiles. Risks for thrombotic adverse cardiovascular events and its components were comparable between the 2 strategies. Subgroup analysis showed that risks for target lesion failure and thrombotic adverse cardiovascular events in the 2-stent group were significantly higher than in the 1-stent group in those with DAPT interruption <1 year, while they were similar in those receiving DAPT maintenance ≥1 year.

Conclusions

Up to 20% of patients who underwent LM bifurcation PCI eventually required a 2-stent strategy, which was as safe as a 1-stent strategy with the use of new-generation drug-eluting stents. Careful pre-emptive case selection as well as prolonged DAPT may be necessary when considering a 2-stent strategy in LM PCI given its higher rate of repeat revascularization and lesion failure than the 1-stent approach.  相似文献   
92.
In patients with aortic regurgitation (AR), a precise preoperative assessment of aortic valve (AV) pathology is important if AV repair or sparing operation is an alternative option. The aim of this study was to assess the diagnostic accuracy of computed tomography (CT) for evaluating the AR mechanism compared with surgical inspection. 59 patients with AR who underwent AV surgery and preoperative cardiac CT were evaluated. AR mechanism was classified into type 1 (aortic dilatation or cusp perforation), type 2 (prolapsed cusp) and type 3 (cusp retraction). Agreement between CT and surgical inspection was obtained. Correlation between aortic regurgitant orifice (ARO) and imaging parameters were evaluated. On surgical inspection, type 1 AR was noted in 22 patients, type 2 in 16 and type 3 in 21. Agreement regarding the AR mechanism on CT was excellent (intra-class correlation coefficient, 0.81). At the patient level, the Cohen’s κ value for CT findings with surgical inspection was of 0.89. At the cusp level, moderate agreement was noted between CT and surgical inspection. In the per-cusp analysis, CT had a sensitivity of 72.6%, specificity of 85.1%, positive predictive value of 73.8% and negative predictive value of 84.3% for the detection of aortic cusp abnormality. The diameter, perimeter and area of aortic annulus had moderate correlation with ARO (r?=?0.54–0.66, P?<?0.001). CT-derived classification of AR mechanism showed excellent agreement with surgical inspection.  相似文献   
93.
There is limited data on the efficacy of paclitaxel-coated balloon (PCB) compared to stents for de novo coronary lesions. The purpose of this study was to compare the efficacy of PCB treatment with stent implantation for de novo coronary lesions after successful plain old balloon angioplasty (POBA) guided by fractional flow reserve (FFR). In 200 patients scheduled for elective percutaneous coronary intervention (PCI) for de novo lesions, FFR was measured after POBA (POBA–FFR). If POBA–FFR was ≥?0.75, patients were treated with PCB (PCB group, n?=?78) or stent (Stent group, n?=?73). If POBA–FFR was <?0.75, stent was implanted as planned (Reference group, n?=?42). The primary endpoint was late lumen loss at 9 months and the secondary endpoint was adverse cardiac events (cardiac death, myocardial infarction, target lesion thrombosis, or repeat revascularization) at 12 months follow-up. There was no between-group differences in the POBA–FFR (0.87?±?0.05 in PCB, 0.89?±?0.06 in stent, p?=?0.101). At 9 months, late lumen loss was significantly lower in the PCB group compared to the Stent group (0.05?±?0.33 vs. 0.59?±?0.76 mm, p?<?0.001). Adverse cardiac events were not different between the PCB, Stent and Reference groups (2.6, 5.5, and 9.5% respectively; p?=?0.430 for PCB vs. Stent group; p?=?0.229 for the reference vs. both other groups). PCB treatment guided by POBA–FFR showed excellent 9 months angiographic and functional results, as well as comparable 12 months clinical outcomes, compared with stent implantation for de novo coronary lesions.  相似文献   
94.
95.
AIM: To study the clinical significance of minimal ascites, which was only defined by the CT and whose nature was not determined preoperatively, in the relationship with the peritoneal carcinomatosis. METHODS: The medical records and the dynamic CT films of 118 patients with gastric cancer were reviewed. Factors associated with peritoneal carcinomatosis were analyzed in 40 patients who had CT-defined ascites of which the nature was surgically confirmed. RESULTS: Only 12.5-25% of the CT-defined minimal ascites, whose volume was estimated to be less than 50 mL, were associated with peritoneal carcinomatosis. When the estimated CT-defined ascitic volume was 50 mL or more, peritoneal carcinomatosis was identified in 75-100%. When CT-defined lymph node enlargements were not found beyond the regional gastric area, perigastric invasions were not suspected, and the size of tumor was less than 3 cm, peritoneal carcinomatosis seemed significantly less accompanied at the univariate analysis. However, except for the minimal volume of CT-defined ascites in comparison with the mild or more, other factors were not confirmed multivariately. CONCLUSION: In the patients with gastric cancer, CT-defined minimal ascites alone is rarely associated with peritoneal carcinomatosis, if it does not accompany other signs suggestive of malignant seeding. Therefore, consideration of active curative resection should not be hesitated, if CT-defined minimal ascites is the only delusive sign.  相似文献   
96.
Complications of acute pancreatitis usually occur in pancreas and its contiguous organs. The prevalence of colonic invasion is rare, however, the consequence is fatal, with mortality above 50%. The initial symptoms and onset times are variable and major affected sites are transverse colon and splenic flexure. The spread of inflammatory exudates into the colon is the main mechanism of colonic invasion. If the colonic stenosis develops, it is necessary to manage it surgically. We report a case who arrived at the hospital with watery diarrhea and abdominal distension in the recovery period of acute alcoholic pancreatitis and was diagnosed as a colonic obstruction in the splenic flexure. The patient underwent loop ileostomy instead of the resection of the lesion because of severe adhesion around the splenic flexure. The patient died due to sepsis 5 days after the operation.  相似文献   
97.
Effector memory T cells (TM) play a key role in the pathology of certain autoimmune disorders. The activity of effector TM cells is under the control of Kv1.3 ion channels, which facilitate the Ca2+ influx necessary for T cell activation and function, i.e. cytokine release and proliferation. Consequently, the knock-down of Kv1.3 expression in effector TM's may be utilized as a therapy for the treatment of autoimmune diseases. In this study we synthesized lipid unilamellar nanoparticles (NPs) that can selectively deliver Kv1.3 siRNAs into TM cells in vitro. NPs made from a mixture of phosphatidylcholine, pegylated/biotinylated phosphoethanolamine and cholesterol were functionalized with biotinylated-CD45RO (cell surface marker of TM's) antibodies via fluorophore-conjugated streptavidin (CD45RO-NPs). Incubation of T cells with CD45RO-NPs resulted into the selective attachment and endocytosis of the NPs into TM's. Furthermore, the siRNA against Kv1.3, encapsulated into the CD45RO-NPs, was released into the cytosol. Consequently, the expression of Kv1.3 channels decreased significantly in TM's, which led to a remarkable decrease in Ca2+ influx. Our results can form the basis of an innovative therapeutic approach in autoimmunity.  相似文献   
98.
This study investigated the empathic response of postpartum women to babies in pain and the underlying neural mechanism. Postpartum women responded with more empathy and speed to babies over other stimuli compared to controls. Brain scans taken 3 months after birth showed more elevated activation in the Middle cingulate cortex/middle frontal gyrus (MCC/MFG) than the controls regardless of the task condition. When compared to the adult and neutral conditions, the posterior cingulate cortex (PCC) region was consistently more activated when postpartum women saw babies than controls. In addition, higher activation levels in the PCC region for the baby condition significantly correlated with faster and more empathic responses to babies. Considering that PCC is a core region for the theory of mind or mentalizing which requires cognitive reasoning to understand others, these results suggest that PCC might be a pivotal neural locus facilitating cognitive efforts to empathize with babies during the postpartum period. In a follow‐up experiment at 12 months after birth, we were still able to observe higher activity in the MCC/MFG of postpartum women. However, previously observed PCC activation patterns disappeared 12 months after birth, despite the women''s response patterns to babies still being maintained. These results suggest that the mentalizing process activated to empathize with babies in the early postpartum period becomes less cognitively demanding over time.  相似文献   
99.
100.
Osteonecrosis of the femoral head (ONFH) is a devastating disease frequently leading to femoral head collapse and hip arthritis. Specifically, non-traumatic ONFH primarily affects young and middle-aged adults. Although compromised local circulation of the femoral head seems to be pathognomonic for the disease, the pathogenesis is perplexing and continues to be an area of scrutiny and research. Comprehension of the pathogenesis is of crucial importance for developing and guiding treatments for the disease. Therefore, we provide an up-to-date consensus on the pathogenesis of non-traumatic ONFH.  相似文献   
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