中国部分地区心房颤动住院病例回顾性调查

目的 了解中国心房颤动(房颤)患者年龄分布、病因(或相关因素)、房颤类型、脑卒中等流行病学特征及不同类型房颤的治疗现状。方法 对1999～2001年中国内地41家医院诊断的心房颤动患者的住院病历进行回顾性分析和统计。结果 (1)共入选9297例，平均年龄65．5岁，男女比为13：12。三年内房颤占同期心血管住院病人比例呈逐年上升趋势，平均7．9％。随年龄增高病例数进行性递增。(2)房颤病因及相关因素统计(单项％)，老年58．1％，高血压40．3％，冠心病34．8％，心衰33．1％，风湿性瓣膜病23．9％，特发性房颤7．4％，心肌病5．4％和糖尿病4．1％等。其中以高龄与高血压的组合最常见。本组患者中2／3有心房增大，1／3有射血分数降低。(3)房颤类型中阵发性占33．7％，持续性16．7％，持久性49．5％。(4)阵发性房颤56．4％采用节律控制治疗，18．2％用心室率控制方法，应用药物以胺碘酮、洋地黄制剂最多，其次为B受体阻滞剂、普鲁帕酮等。(5)慢性房颤82．8％接受心室率控制治疗，常用药物为地高辛、B受体阻滞剂及钙拮抗剂。在持续性房颤患者中，试行复律者不足1／2，其中31．1％复律后可维持稳定窦性心律，应用药物以胺碘酮最多，其次为普鲁帕酮、奎尼丁、索他洛尔等。(6)本组脑卒中患病率为17．5％。对非瓣膜病房颤患者的脑卒中危险因素调查显示，其与性别、心房大小无显著相关，而与高龄、高血压、心衰及房颤类型密切相关：(7)本组患者64．5％接受了抗血栓治疗，其中抗血小板治疗占57．9％，长期抗凝治疗者仅6．6％。二种抗血栓治疗均有显著较低的脑卒中发生率，但抗凝与抗血小板二组比较其脑卒中发生率差别无显著性。结论中国房颤患者在年龄分布、病因及相关因素、房颤类型、脑卒中危险因素等流行病学特点与国外报道极为相似。阵发性房颤以节律控制治疗为主。慢性房颤绝大多数用心室率控制治疗。虽有64．5％患者接受了抗血栓治疗，但以抗血小板治疗为主。抗凝及抗血小板治疗二组的脑卒中发生率差异无显著性。  

Profile and prevalence of aspirin resistance in patients with cardiovascular disease

We determined the prevalence and clinical predictors of aspirin resistance by prospectively studying 325 patients with stable cardiovascular disease who were receiving aspirin (325 mg/day for > or =7 days) but no other antiplatelet agents. We also compared the detection of aspirin resistance with optical platelet aggregation, a widely accepted method, with a newer, more rapid method, the platelet function analyzer (PFA)-100, a whole blood test that measures platelet adhesion and aggregation ex vivo. Blood samples were analyzed in a blinded fashion for aspirin resistance by optical aggregation using adenosine diphosphate (ADP) and arachidonic acid, and by PFA-100 using collagen and/or epinephrine and collagen and/or ADP cartridges to measure aperture closure time. Aspirin resistance was defined as a mean aggregation of > or =70% with 10 microM ADP and a mean aggregation of > or =20% with 0.5 mg/ml arachidonic acid. Aspirin semiresponders were defined as meeting one, but not both of the above criteria. Aspirin resistance by PFA-100 was defined as having a normal collagen and/or epinephrine closure time (< or =193 seconds). By optical aggregation, 5.5% of the patients were aspirin resistant and 23.8% were aspirin semiresponders. By PFA-100, 9.5% of patients were aspirin resistant. Of the 18 patients who were aspirin resistant by aggregation, 4 were also aspirin resistant by PFA-100. Patients who were either aspirin resistant or aspirin semiresponders were more likely to be women (34.4% vs 17.3%, p = 0.001) and less likely to be smokers (0% vs 8.3%, p = 0.004) compared with aspirin-sensitive patients. There was a trend toward increased age in patients with aspirin resistance or aspirin semiresponders (65.7 vs 61.3 years, p = 0.06). There were no differences in aspirin sensitivity by race, diabetes, platelet count, renal disease, or liver disease.  

BiPAP鼻罩式机械通气治疗左心衰竭

目的 探讨BiPAP鼻罩式双向正压机械通气治疗左心衰竭的疗效，适合的通气压力等具体方法，了解其对血液动力学的影响。方法 对35例各种病因所致严重左心衰竭患在常规药物治疗基础上采用BiPAP ST-D-20,ST-D-30呼吸机经鼻罩双向正压通气，以流量触发，压力支持，所以给吸气压8－15cm H2O，呼气压2－5cm H2O，氧浓度28－35％，患尽量闭口呼吸，对其中8例患插入Swan-Ganz漂浮热稀释导管，用HPMI166A型心电监护仪及配套血液动力学插件测定及计算各项血液动力学指标。同时与35例常规药物治疗组进行对比。结果 BiPAP组经鼻罩式机械通气后所有患呼吸频率减慢，心率下降，呼吸困难缓解，治疗总有效率为100％，对血压无明显影响，呼吸困难开始缓解时间为10min-3h，对8例BiPAP鼻罩式机械通气患血液动力学监测显示，平均肺动脉压和肺毛细血管楔压下降，心指数无明显变化，心搏指数增加，对照组在相应时间治疗总有效率仅为63．33％，结论 BiPAP鼻罩式双向正压机械通气是治疗左心衰竭的快速有效方法。  

超声测量颈动脉内膜中层厚度与颈动脉斑块的关系

为了探讨颈动脉内膜中层厚度与局限性颈动脉斑块的联系 ,对 91名受试对象的颈总动脉内膜中层厚度及颈内动脉和颈动脉分叉处的斑块进行超声检测 ,并将颈动脉内膜中层厚度进行分级。结果观察到有斑块者较无斑块者其颈动脉内膜中层厚度明显增加 ( 0 .83± 0 .16mm比 0 .6 4± 0 .12mm ,P <0 .0 1) ,且随斑块的严重程度增加 ,其内膜中层厚度呈增厚趋势。该结果支持颈总动脉内膜中层厚度与颈动脉局限性动脉粥样硬化斑块明显相关 ,提示颈动脉内膜中层厚度增厚可能是颈动脉粥样硬化的早期表现  

脉压指数评价血管硬化的可行性探讨

目的　用脉压指数评价血管硬化的可行性 ,比较脉压 (PP)与脉压指数 (PPI)评价血管硬化何者为优。方法　定义脉压指数 (PPI)等于脉压除以收缩压。测量 2 0例老年高血压病患者血压 ,计算每例患者的PP及PPI的变化幅度。把流行病学调查而得 735例老年高血压病患者 ,根据不同的PP及PPI分为四组 ,分析心电图异常与两者的关系 ,同时行Logistic回归分析。结果　PPI的变化幅度要小于PP ,P <0 0 0 0 1;PP与PPI对心电图异常的影响相似 ,但PPI的相对危险性大于PP ,前者为1 86 8,后者为 1 783。结论　用PPI评价血管硬化理论上有依据 ,可从非线形弹性腔理论推得出PPI=(Cs Cd) / (Cs Co) ,并且在一定程度上克服了PP评价血管硬化的缺陷 ,是临床可行的评价方法  

Transcatheter closure of ventricular septal defects

Between January and October, 1987, we attempted percutaneous transcatheter closure of seven ventricular septal defects (VSD) in six patients; none of the patients was a candidate for operative management. Patients' ages ranged from 8 months to 82 years (6.0-70 kg); diagnoses included postinfarction VSD (n = 4), congenital VSD (n = 1), and postoperative congenital VSD (n = 2). Indications for VSD closure were shock or respiratory failure (n = 5) or multiple episodes of endocarditis (n = 1). Closure was attempted with a Rashkind double umbrella: VSDs were crossed via the left ventricle and a guide wire was advanced to the right heart, snared with a venous catheter, and used to direct a long sheath (and ultimately the double umbrella) across the VSD. We crossed the VSD in all seven attempts, and a 17-mm double umbrella was successfully placed in each VSD. In the first (postinfarction) patient with the largest (12 mm) VSD, the umbrella embolized after 20 seconds to the pulmonary artery (without reducing flow). The other six umbrellas remained in position, either diminishing or abolishing the left-to-right shunts. Postinfarction patients had increasing VSD shunting over the next several days and died; at postmortem, the umbrellas remained well positioned in the septum, with other VSDs present. All three congenital VSDs had absent or diminished shunts after umbrella closure. These preliminary data indicate that transcatheter VSD closure is feasible in selected cases.  

Erythropoietin and VEGF exhibit equal angiogenic potential

Erythropoietin (Epo) is a hormone regulating proliferation and differentiation of erythroid cells. The hypothesis that hematopoietic and endothelial cells share a common hemangioblast progenitor among others is based on the finding that both cell lineages express cell surface antigens like CD31 and CD34. In this study we investigated the angiogenic potential of recombinant human erythropoietin (rHuEpo) on endothelial cells derived from human adult myocardial tissue. In addition, we compared the angiogenic potential of rHuEpo to that of other cytokines (VEGF, aFGF) and combinations of growth factors. Samples of myocardial tissue (cardiac auricle) were obtained during coronary bypass surgery, embedded in a fibrin gel matrix, and cultured for 21 days. Capillary sprouting was measured with an eye-piece graticule under an inverted-phase contrast microscope. Tube-forming endothelial cells were characterized by immunohistochemistry and RT-PCR. Using a concentration of 2.5 U/ml, we found that rHuEpo stimulates capillary outgrowth up to 220%, compared to the nonstimulated physiological outgrowth. Epo therefore exhibits the same angiogenic potential on endothelial cells in our in vitro assay as VEGF(165) (230% increase). Erythropoietin stimulates capillary outgrowth in an in vitro angiogenesis assay using adult human myocardial tissue. This implies a role of erythropoietin in vasoproliferative processes. rHuEpo may serve as a direct angiogenic substance in patients with ischemic heart disease.  

Ionic mechanisms of electrical remodeling in human atrial fibrillation

OBJECTIVES: Atrial fibrillation (AF) is associated with a decrease in atrial ERP and ERP adaptation to rate as well as changes in atrial conduction velocity. The cellular changes in repolarization and the underlying ionic mechanisms in human AF are only poorly understood. METHODS: Action potentials (AP) and ionic currents were studied with the patch clamp technique in single atrial myocytes from patients in chronic AF and compared to those from patients in stable sinus rhythm (SR). RESULTS: The presence of AF was associated with a marked shortening of the AP duration and a decreased rate response of atrial repolarization. L-type calcium current (ICa,L) and the transient outward current (Ito) were both reduced about 70% in AF, whereas an increased steady-state outward current was detectable at test potentials between -30 and 0 mV. The inward rectifier potassium current (IKI) and the acetylcholine-activated potassium current (IKACh) were increased in AF at hyperpolarizing potentials. Voltage-dependent inactivation of the fast sodium current (INa) was shifted to more positive voltages in AF. CONCLUSIONS: AF in humans leads to important changes in atrial potassium and calcium currents that likely contribute to the decrease in APD and APD rate adaptation. These changes contribute to electrical remodeling in AF and are therefore important factors for the perpetuation of the arrhythmia.  

Usefulness of multislice computed tomography for detecting obstructive coronary artery disease

The latest generation of multislice spiral computed tomography (MSCT) scanners is capable of noninvasive coronary angiography. We evaluated its diagnostic accuracy to detect stenotic coronary artery disease (CAD). In 53 patients with suspected CAD, contrast-enhanced MSCT and conventional angiography were performed. The CT data were acquired within a single breathhold, and isocardiophasic slices were reconstructed by means of retrospective electrocardiographic gating. Coronary segments of > or = 2 mm in diameter, measured by quantitative angiography, were evaluated. In 70% of the 358 available segments, image quality was regarded as adequate for assessment. The overall sensitivity, specificity, and positive and negative predictive values to detect > or = 50% stenotic lesions in the assessable segments were 82% (42 of 51 lesions), 93% (285 of 307 nonstenotic segments), and 66% and 97%, respectively, regarding conventional quantitative angiography as the gold standard. Proximal segments were assessable in 92%, and distal segments and side branches in 71% and 50%, respectively. Including the undetected lesions in non-assessable segments, overall sensitivity decreased to 61% but remained 82% for lesions in proximal coronary segments. MSCT correctly predicted absent, single, or multiple lesions in 55% of patients. Thus, despite potentially high image quality, current MSCT protocols offer only reasonable diagnostic accuracy in an unselected patient group with a high prevalence of CAD.  

Transplantation of progenitor cells and regeneration enhancement in acute myocardial infarction: final one-year results of the TOPCARE-AMI Trial

OBJECTIVES: The Transplantation of Progenitor Cells And Regeneration Enhancement in Acute Myocardial Infarction (TOPCARE-AMI) trial investigates both safety, feasibility, and potential effects on parameters of myocardial function of intracoronary infusion of either circulating progenitor cells (CPC) or bone marrow-derived progenitor cells (BMC) in patients with acute myocardial infarction (AMI). BACKGROUND: In animal experiments, therapy with adult progenitor cells was shown to improve vascularization, left ventricular (LV) remodeling, and contractility after AMI. METHODS: A total of 59 patients with AMI were randomly assigned to receive either CPC (n = 30) or BMC (n = 29) into the infarct artery at 4.9 +/- 1.5 days after AMI. RESULTS: Intracoronary progenitor cell application did not incur any measurable ischemic myocardial damage, but one patient experienced distal embolization before cell therapy. During hospital follow-up, one patient in each cell group developed myocardial infarction; one of these patients died of cardiogenic shock. No further cardiovascular events, including ventricular arrhythmias or syncope, occurred during one-year follow-up. By quantitative LV angiography at four months, LV ejection fraction (EF) significantly increased (50 +/- 10% to 58 +/- 10%; p < 0.001), and end-systolic volumes significantly decreased (54 +/- 19 ml to 44 +/- 20 ml; p < 0.001), without differences between the two cell groups. Contrast-enhanced magnetic resonance imaging after one year revealed an increased EF (p < 0.001), reduced infarct size (p < 0.001), and absence of reactive hypertrophy, suggesting functional regeneration of the infarcted ventricles. CONCLUSIONS: Intracoronary infusion of progenitor cells (either BMC or CPC) is safe and feasible in patients after AMI successfully revascularized by stent implantation. Both the excellent safety profile and the observed favorable effects on LV remodeling, provide the rationale for larger randomized double-blind trials.