Prognostic value of plasma tissue factor and tissue factor pathway inhibitor for cardiovascular death in patients with coronary artery disease: the AtheroGene study

BACKGROUND: Tissue factor (TF) and its specific inhibitor, tissue factor pathway inhibitor (TFPI), are important contributors to the initiation of the coagulation process. OBJECTIVES: To compare plasma levels of soluble TF (sTF) and free-TFPI (f-TFPI) between patients with stable angina pectoris (SAP) and acute coronary syndrome (ACS) and to assess the impact of the two variables on long-term prognosis. PATIENTS/METHODS: Patients with SAPs (n = 1146) and acute coronary syndrome (n = 523) from the AtheroGene study were included and followed for 2.3 years. Because of the strong impact of unfractionated heparin (UFH) on f-TFPI levels, but not on sTF levels, patients having received UFH before blood drawing were excluded from the analyses on f-TFPI (n = 226). RESULTS: On admission, no significant differences in sTF levels were observed between SAP and ACS patients. By comparison to patients with stable angina, f-TFPI levels significantly increased in patients with acute unstable angina and further increased in patients presenting with non-ST-elevation myocardial infarction and ST-elevation myocardial infarction (P < 10(-4)). Among the 1669 individuals with a coronary artery disease, 56 died from a cardiovascular cause. In prospective analyses, high sTF levels were independently associated with an increased risk of cardiovascular death in individuals with ACS (fully adjusted hazard ratio associated with one quartile increase = 2.06; 95% confidence interval 1.24-3.45; P = 0.006) but not in those with SAP (hazard ratio = 1.07; 95% confidence interval 0.78-1.46; P = 0.67). In SAP and ACS patients, high f-TFPI levels were not independently associated with an increased risk of cardiovascular death. CONCLUSIONS: Plasma sTF levels were predictive of cardiovascular mortality in individuals with ACS, whereas f-TFPI levels were associated with the severity of myocardial damage on admission but were not independently related to outcome.     

在聚乙氧基辛基苯基醚存在下氯米帕明的电分析特性

在聚乙氧基辛基苯基醚存在下氯米帕明的电分析特性张正奇，陈展光，陈声宗，曾鸽鸣，杨植岗（湖南大学化学化工系，长沙４１００８２）氯米帕明（ｃｌｏｍｉｐｒａｍｉｎｅ，ＣＭＩ）能选择性地抑制中枢神经系统内５－ＨＴ的重吸收，可消除抑郁心境，恢复活力。本品使用安...     

下胸段硬膜外阻滞在单肺通气期间对肺内分流的影响

目的探讨全麻下下胸段硬膜外阻滞对单肺通气期间肺内分流(Qs/Qt)的影响。方法术中需行单肺通气的30例择期开胸手术患者,ASAⅡ～Ⅲ,随机分为全麻组(GA组,n=15),全麻复合下胸段硬膜外组(GE组,n=15)。两组病人分别于麻醉前、双肺通气30min、单肺通气5、15、30min时采动脉血及混合静脉血,行血气分析,并计算出Qs/Qt等。结果两组患者在单肺通气后5、15、30min,Qs/Qt均增加(P<0.01),动脉氧分压(PaO2)较双肺通气时下降(P<0.01)。但在各时间点两组Qs/Qt以及PaO2无显著性差异。结论下胸段硬膜外阻滞对单肺通气期间肺内分流和动脉氧合无明显影响,可安全用于开胸单肺通气患者的麻醉。     

Tilt Table Testing of Young Adult Patients: Improved Speed and Sensitivity Using an Isoproterenol Bolus and a Continuous 60° Tilt

The tilt table is a diagnostic device used to induce vagal syncope and determine etiology. Sensitivity enhancing techniques, such as the administration of isoproterenol, can be applied to children and young adults to compensate for the otherwise low sensitivity (20%-30%) observed in that population. This study describes an improved test that offers a simplified approach while decreasing the amount of time involved by up to 50%, without compromising sensitivity. This 45-minute procedure relies on sensitization with isoproterenol administered as a 2- to 8-μg bolus instead of a continuous infusion. The isoproterenol is injected at the 30th minute of a 45-minute 60° tilt test without returning the patient to the supine position. In this study, the isoproterenol bolus tilt test was found to be "positive" in 24 of 30 patients reporting unexplained syncope: 10 cases before the 30th minute (11.2 ± 8.4 min) and 14 cases after administration of 5.1 ± 1,9 μg of isoproterenol.     

Inter- and Intraindividual Variations in Shortening of Ventricular Effective Refractory Period After an Abrupt Decrease in Pacing Cycle Length

After an abrupt decrease in pacing cycle length (PCL), the ventricular effective refractory period (VERP) shortens. The pacing protocol needed to determine accurate and reproducible values for the VERP during this process is elaborate and time consuming. In this study, steady-state values of VERP at 800 and 350 msec PCL and dynamic values of VERP due to an abrupt change in PCL from 800 to 350 msec were determined. This was done for 11 different dogs to test the interindividual variation and repetitively in the same dog to test the intraindividual variation. The results for steady-state and dynamic values of the VERP show a wide range for both groups. This means that accurate prediction of steady-state and dynamic values of VERP based on previous measurements is not possible.     

Clinical outcome of patients with venous thromboembolism and recent major bleeding: findings from a prospective registry (RIETE)

BACKGROUND: Patients who have experienced a recent major bleeding episode are usually excluded from clinical studies of venous thromboembolism (VTE) treatment. Therefore, recommendations based on evidence from clinical trials may not be suitable for these patients. The Registro Informatizado de la Enfermedad TromboEmbolica (RIETE) is a multicenter, observational registry designed to gather and analyze data on VTE treatment practices and clinical outcomes in patients with acute VTE. OBJECTIVES: The aim of this analysis was to study outcomes of patients with VTE who had experienced recent major bleeding (< 30 days prior to VTE diagnosis). METHODS: Patients with objectively confirmed symptomatic acute VTE are consecutively enrolled into the RIETE registry. Patient characteristics, details of antithrombotic therapy, and clinical outcomes at 3 months were recorded. RESULTS: Of 6361 patients enrolled up to January 2004, 170 (2.7%) had experienced recent major bleeding: 69 (40.6%) gastrointestinal tract, 60 (35.3%) intracranial, 41 (24.1%) other. The incidences of major bleeding (4.1%) and recurrent pulmonary embolism (PE) (2.4%) were significantly higher in patients with recent major bleeding. Among them, patients with cancer had an increased incidence of major bleeding [odds ratio (OR) 10.0, 95% confidence interval (CI) 2.3, 50; P < 0.001] and fatal PE (OR 4.1, 95% CI 0.98, 17; P < 0.05). CONCLUSIONS: Patients with VTE and recent major bleeding prior to VTE diagnosis (2.7% of total enrolled patients) had poorer clinical outcomes compared with those who had not experienced recent major bleeding. In patients who had recent major bleeding prior to enrollment, those with cancer had a poorer clinical outcome than those without cancer.     

One-to-Two Atrioventricular Conduction Causing Nonreentrant Tachycardia: Successful Treatment with Radiofrequency Ablation

The anatomical substrate for AV nodal reentrant tachycardia (AVNRT) is well known and is due to anterograde conduction through a siow conducting pathway and retrograde conduction using a fast conducting path way. In this report, we describe a patient with AVNRT who also presented with frequent episodes of paroxysmal nonreentrant tachycardia due to the occurrence of two conducted ventricular beats for each sinus depolarization. Palpitations and arrhythmias were abolished after radiofrequency ablation of the slow pathway.     

Initial Experience with a New Single Chamber, Dual Sensor Rate Responsive Pacemaker

In August 1991, a new single chamber pacemaker became available that utilizes information from two sensors, activity and stimulus-to-T wave (QT) interval. We are reporting on the first 90 implants in 21 centers. T wave sensing was adequate at implantation in 88/90 patients, with a safety margin of > 100% in 86/90, Activity sensing was adequate in all patients. The contribution of each sensor fsensor blending) is programmable for each patient. Of 75 patients assessed at 1 month after implant, three have been programmed to "Activity-Only" mode, and 72 to dual sensor mode. Of these, 18 have been programmed to "QT < Activity," 48 to "QT = Activity," and 6 to "QT > Activity." Forty-five patients underwent exercise testing in dual sensor mode and a subgroup of 15 also underwent exercise testing in Activity-Only mode. The dual sensor mode produced a more gradual increase in pacing rate. Sensor Cross Checking^tmsatisfactorily prevented a sustained high pacing rate in tests of false-positive activity sensing (tapping, vibrating pacemaker, or static pressure). The maximum pacing rate on walking downstairs (94.2 ± 7.2 ppm) was similar to that produced by walking upstairs (91.6 ± 5.9 ppm). We conclude that initial assessment of this dual sensor, single chamber, rate responsive pacemaker confirms that the algorithm for combining data from two sensors functions satisfactorily. Dual sensor rate responsive pacing may offer significant advantages over single sensor devices, and further studies of this novel device are indicated.     

A Prospective, Randomized Evaluation of a Nonthoracotomy Implantable Cardioverter Defibrillator Lead System

Nonthoracotomy lead systems for ICDs have been developed that obviate the need for a thoracotomy and reduce the morbidity and mortality associated with implantation. However, an adequate DFT cannot be achieved in some patients using transvenous electrodes alone. Thus, a new subcutaneous "array" electrode was designed and tested in a prospective, randomized trial that compared the DFT obtained using monophasic shock waveforms with a single transvenous lead alone that has two defibrillating electrodes, the transvenous lead linked to a subcutaneous/submuscular patch electrode, and the transvenous lead linked to the investigational array electrode. There were 267 patients randomized to one of the three nonthoracotomy ICD lead systems. All had DFTs that met the implantation criterion of ≤ 25 J. The resultant study population was 82% male and 18% female, mean age of 63 ± 11 years. The indication for ICD implantation was monomorphic VT in 70%, VF in 19%, monomorphic VT/VF in 6%, and polymorphic VT in 4% of the patients, respectively. The mean LVEF was 0.33 ± 0.13. The mean DFT obtained with the transvenous lead alone was 17.5 ± 4.9 J as compared to 16.9 ± 5.5 J with the lead linked to a patch electrode (P = NS), and 14.9 ± 5.6 with the lead linked to the array electrode (array versus lead alone, P = 0.0001; array versus lead/patch, P = 0.007). The results of this investigation suggest that the subcutaneous array may be superior to the standard patch as a subcutaneous electrode to lower the DFT and increase the margin of safety for successful nonthoracotomy defibrillation.