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91.
BACKGROUNDThree-vessel disease (TVD) with a SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score of ≥ 23 is one of the most severe types of coronary artery disease. We aimed to take advantage of machine learning to help in decision-making and prognostic evaluation in such patients.METHODSWe analyzed 3786 patients who had TVD with a SYNTAX score of ≥ 23, had no history of previous revascularization, and underwent either coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) after enrollment. The patients were randomly assigned to a training group and testing group. The C4.5 decision tree algorithm was applied in the training group, and all-cause death after a median follow-up of 6.6 years was regarded as the class label.RESULTSThe decision tree algorithm selected age and left ventricular end-diastolic diameter (LVEDD) as splitting features and divided the patients into three subgroups: subgroup 1 (age of ≤ 67 years and LVEDD of ≤ 53 mm), subgroup 2 (age of ≤ 67 years and LVEDD of > 53 mm), and subgroup 3 (age of > 67 years). PCI conferred a patient survival benefit over CABG in subgroup 2. There was no significant difference in the risk of all-cause death between PCI and CABG in subgroup 1 and subgroup 3 in both the training data and testing data. Among the total study population, the multivariable analysis revealed significant differences in the risk of all-cause death among patients in three subgroups.CONCLUSIONSThe combination of age and LVEDD identified by machine learning can contribute to decision-making and risk assessment of death in patients with severe TVD. The present results suggest that PCI is a better choice for young patients with severe TVD characterized by left ventricular dilation.

Coronary artery disease (CAD) is the leading cause of death and disability worldwide.[1] Three-vessel disease (TVD) is the most severe form of CAD and is characterized by significant stenosis in all three major coronary arteries. The application of myocardial revascularization techniques, including coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), has significantly improved the clinical outcomes of patients with severe CAD. CABG has traditionally been the standard therapy for complex coronary lesions, including TVD.[2] In recent years, with the advancements in PCI technology and the accumulation of operators’ experience, the incidence of periprocedural and long-term adverse events of PCI has substantially decreased, and PCI has been gradually applied in the treatment of TVD.[3,4] Current guidelines recommend use of the SYNergy between PCI with TAXus and cardiac surgery (SYNTAX) score and diabetes status to guide the revascularization strategy for patients with TVD.[5,6] Current practice guidelines do not recommend PCI for patients with TVD with a SYNTAX score of ≥ 23. However, using the SYNTAX score to guide clinical decision-making between PCI and CABG remains controversial, and its reasonability has been questioned since a newly published meta-analysis showed no significant association between the SYNTAX score and the comparative effectiveness of PCI and CABG.[7] Moreover, the SYNTAX score is a quantitative indicator of the anatomical complexity of TVD and does not include clinical variables that may have significant effects on the patient’s prognosis. Whether some patients with specific clinical characteristics can obtain a comparable or even greater survival benefit from PCI than from CABG is unclear. Moreover, risk assessment for patients with TVD after revascularization therapy remain challenging.[810]Machine learning has recently emerged as an important research method and has been successfully applied in many scientific fields, including clinical medicine.[1113] The decision tree algorithm, a common approach in machine learning, can handle non-linearity, heterogeneous effects, and high-dimensional features and partition a trial population into subgroups characterized by multiple simultaneous characteristics.[14] In the present study involving a large cohort of patients with TVD with a SYNTAX score of ≥ 23, we employed a decision tree algorithm to generate specific subgroups, compared the long-term prognosis between patients who underwent PCI or CABG in each subgroup, and conducted a comparative analysis of the long-term prognosis between subgroups generated by machine learning. We evaluated whether machine learning can help in selecting the optimal revascularization method and assessing risk in patients with severe TVD.  相似文献   
92.
宫玉典  刘文娟  冯植 《现代医院》2006,6(6):122-123
论述实施科主任领导下的责任医师负责制指导思想,介绍科主任领导下的责任医师负责制奖金核算内容、实施方法、主要步骤和工作成效。指出发挥好责任医师作用,对构建和谐医患关系很有必要。  相似文献   
93.
体外反搏对减轻高脂饲养猪产生动脉粥样硬化的实验研究   总被引:1,自引:0,他引:1  
目的探讨体外反搏对减轻高脂饲养猪产生动脉粥样硬化的效果及机制。方法选雄性乳猪16头,用高脂喂养建立动脉粥样硬化模型,对模型猪进行36h体外反搏治疗。对腹主动脉作苏丹Ⅲ染色,分析脂质浸润阳性率;用基因芯片分析猪的动脉血管内皮细胞基因的表达。结果腹主动脉苏丹Ⅲ染色图像定量分析阳性率,高脂组为6.49%±0.84%,高脂加反搏组为2.29%±0.46%,两组差异有统计学意义(P<0.05)。发现改变的基因:芯片1(反搏组Cy3/高脂组Cy5):整合素β10.06、CTGF0.28;芯片2(反搏组Cy3/高脂组Cy5):整合素β10.62、CTGF0.39。结论体外反搏可以下调内皮细胞整合素β1、CTGF基因的表达,降低血管內皮细胞对脂质的摄取,起到抗动脉粥样硬化的作用。  相似文献   
94.
软腭骨瘤1例报告及文献复习   总被引:2,自引:0,他引:2  
骨瘤是常见的由分化成熟的骨组织构成的良性肿瘤,多来源于邻近骨质,发生于骨膜内层骨母细胞,由成骨性纤维组织、成骨细胞及所产生的新生骨组成。发生于口腔软组织的骨瘤极为罕见,作者报道1例软腭骨瘤病例,结合有关文献对其组织来源、病理分型、鉴别诊断和治疗等进行了讨论。  相似文献   
95.
目的:研究清利塞鼻洗液术腔冲洗对内镜鼻窦术后鼻黏膜形态和功能的影响。方法:将Ⅰ型2、3期及Ⅱ型慢性鼻窦患者85 例于行内镜鼻窦术后,随机分为清利塞组与对照组;冲洗术腔时清利塞组用清利塞鼻洗液,对照组按传统方法用地塞米松+硫酸庆大霉素;观察其术腔清洁时间、术腔黏膜病变出现时间、上皮化时间以及术后症状改善及疗效等。结果:两组在术腔清洁时间及上皮化时间组间差异有统计学意义(P<0.0005,0.01<P<0.025),术腔黏膜病变出现时间差异无统计学意义(P>0.05),1年后临床疗效及术后症状、体征改善清利塞组优于对照组(P<0.05)。结论:清利塞鼻洗液在内镜鼻窦手术后术腔冲洗较传统冲洗方法有显著的优点,值得进一步研究应用。  相似文献   
96.
目的 :观察多巴胺对高原地区老年肺心病患者呼吸肌功能的影响。方法 :4 8例老年肺心病患者随机分为观察组 (A组 )和对照组 (B组 ) ,每组 2 4例。A组用多巴胺 6 0mg加入 10 %葡萄糖溶液 15 0ml,以 5 μg·kg-1·min-1的速度静滴作为治疗。B组用等量 10 %葡萄糖溶液 ,以同样速度静滴作为对照。用药前、后测定肺功能、呼吸肌功能和心功能。结果 :用药前 ,两组一秒钟用力呼气容积占预计值百分比 (FEV1%预计值 )、动脉血氧分压 (PaO2 )、二氧化碳分压 (PaCO2 )、最大吸气压 (PImax)、最大呼气压 (PEmax)、最大跨膈压 (Pdimax)、呼吸肌力量指数 (RMS)、心脏指数 (CI )和心搏指数 (SI)差异无显著性。用药后 ,A组PI max、PEmax、Pdimax、RMS、CI、SI显著高于用药前 (P均 <0 .0 1) ,B组各项指标无显著性变化。A组用药后PImax、PEmax、Pdimax、RMS与CI呈显著正相关 (r=0 .6 74、0 .5 4 1、0 .6 6 9、0 .6 2 9,P均 <0 .0 1)。结论 :小剂量多巴胺有显著增强呼吸肌功能的作用 ,可作为高原肺心病的辅助治疗。  相似文献   
97.
Objective To evaluate the accuracy of automated quantification of myocardial perfusion imaging (MPI) using a method based on a Western normal database for the detection of coronary artery disease (CAD) in a group of Chinese patients. Methods Seventy-two Chinese patients who underwent coronary angiography (CAG) and MPI within 3 months were recruited into this study. Eighty selected from 140 Chinese patients with low probability of CAD ( < 5% ) were enrolled into local normal database of 99Tcm-methoxyisobutylisonitrile (MIBI) MPI using Cedars quantitative perfusion SPECT (QPS) database. Two Western MPI normal databases (CSMC MibiMbiAuto and Mibimibi) were used for processing the Chinese CAD patients recruited in this study, and the results were compared with those using local normal database and visual interpretation. T-test and z-test were used for statistical analysis. Results The extent (EXT)measurement obtained from Mibimibi and local database was ( 10.73 ± 14.54)% and ( 14.22 ± 16.51 )%,respectively ( t = 7.87, P < 0.001 ); the severity (SEV) was 1.07 ± 0.93 and 1.34 ± 1.20, respectively ( t =7.45, P<0.001). The area under curve(AUC) by using EXT measurement for local database (0.85 ±0.05) was larger than that for CSMC MibiMbiAuto ( AUC = 0.72 ± 0.06, z = 2.50, P < 0.01 ) and Mibimibi ( AUC = 0.77 ± 0.06, z = 2.47, P = 0.014). The AUC of local database showed no significant difference from that of visual interpretation (AUC=0.83 ±0.05, z=0.05, P>0.05). Conclusion Quantification of MPI of our Chinese patients using Western normal database would decrease the accuracy for the detection of CAD.  相似文献   
98.
目的探讨环孢素A(CsA)对大鼠骨折愈合的影响。方法 25只右侧股骨干横行骨折大鼠随机分成2组,实验组15只,对照组10只。实验组骨折当天皮下注射CsA 1.5mg/kg,对照组皮下注射生理盐水1ml,共注射8周,检测股骨干骨密度和生物力学性能检测。结果实验组和对照组右侧股骨干的骨折愈合后,其力学性能参数最大扭力、最大转角和能量吸收仍显著小于各自左侧正常股骨干。实验组右侧股骨干骨折愈合后的最大扭力、最大转角、抗扭刚度和能量吸收与对照组比较均无显著差异,骨折端骨密度也无显著差异。结论 1.5mg/kg剂量的CsA对股骨干骨折愈合无显著影响。  相似文献   
99.
我院1996年5月 ̄2004年7月,应用改良阴囊纵隔皮瓣一期修复尿道下裂18例,效果良好,现报告如下。1临床资料与结果1.1一般资料本组18例,平均年龄6岁(3 ̄12岁),阴茎后1/3型6例,阴茎阴囊型10例,阴囊型2例,阴囊发育均良好。1.2手术方法1.2.1将阴茎拉直用2-0丝线贯穿阴茎头部作牵引,于  相似文献   
100.
目的 评价神经外科躁动患者应用右美托咪定和丙泊酚镇静治疗的效果及不良反应.方法 选择2010年3月~2011年3月入住武汉大学人民医院ICU中的神经外科急重症及术后躁动患者60例,随机分为两组,右美托咪定组(D组)和丙泊白酚组(P组),监测给药前(T1)及给药后10 min(T2)、1 h(T3)、2 h(T4)、6 h(T5)和次日清晨7:00(T6)的平均动脉压、心率、呼吸频率、脉搏血氧饱和度,记录药物起效时间、达到Ramsay镇静评分2~4级时药物平均输注速度.结果 两组药物起效时间比较差异有高度统计学意义(P<0.01),D组患者用药后血压及心率均有所下降(P<0.05),用药后呼吸频率与T1相比虽有所下降,但差异无统计学意义(P>0.05);P组镇静治疗后血压较给药前下降,差异有统计学意义(P<0.05),与T1比较,T2~4的心率明显下降(P<0.05),用药后10 min内即观察到呼吸频率下降,T2与T1相比差异有统计学意义(P<0.05).结论 右美托咪定和丙泊酚微量泵持续输入用于神经外科躁动患者镇静安全有效,丙泊酚可应用于躁动患者的快速镇静,右美托咪定镇静过程中无明显呼吸抑制发生,但要注意防范血压下降和心率减慢的不良反应.  相似文献   
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