A randomized trial comparing two different approaches of pacemaker selection.

AIMS: DDD-pacemakers are favoured in patients with sick-sinus-syndrome or AV-block. However, AAI-pacemakers for sick-sinus-syndrome or VDD-pacemakers for AV-block may provide similar benefit with lower costs. The aim is to show that a tailored approach (TA) with arrhythmia-specific pacemaker selection was equal to a standard approach (SA) regarding quality of life (QoL) at lower costs. METHODS AND RESULTS: The study was prospective and randomized with QoL as primary endpoint. Secondary endpoints were a combined endpoint of all-cause mortality, worsening heart failure or angina, atrial fibrillation (AF), stroke, these endpoints individually and costs. Of 198 patients (age 77 +/- 10 years, 43% female, ejection fraction 54 +/- 12%, follow-up 38 +/- 15 months), 94 were randomized to SA and 104 to TA. Thirty-two patients (34%) died in the SA group vs. 25 (24%) in the TA (P= ns). QoL showed no differences in all dimensions. The combined secondary endpoint was reached more frequently with SA (51%) compared to TA (37%, P = 0.045). There was no difference regarding all single secondary endpoints. Hardware costs were reduced by 15% (P < 0.0001). CONCLUSION: In long-term follow-up, a TA is equal to SA regarding the primary endpoint QoL and secondary endpoints as AF and mortality. Depending on the healthcare system, it may significantly reduce costs.     

心脏手术后的认知功能障碍

大脑功能障碍是指智力下降等不同程度脑功能改变。随着心脏外科的发展，有关中枢神经系统并发症日益受到重视。 1 危险因素 术前已有中风、主动脉近端硬化、贫血与老龄化、高血压和糖尿病等均可使体外循环后中风风险增加。术中发生中风的主要风险因子是体外循环时间和反复地钳夹主动脉。其他如围术期心律失常、低心排综合征等情况也会使体外循环后认知功能障碍增加。     

Management of adult patients with a left ventricular assist device.

The number of left ventricular assist device (LVAD) implantations is growing as a result of increased waiting periods for cardiac transplantation and the decreased availability of organ donors. Furthermore, the Food and Drug Administration (FDA) has approved permanent LVAD support. After an acute hospitalization, patients with LVADs may need prolonged convalescence in a healthcare facility because they have complex medical needs and are physically disabled. Admission criteria need to be developed as essential patient and nursing competencies need to be defined as a part of a successful LVAD program in an acute rehabilitation center. Acute rehabilitation centers can help patients with LVADs transition to a home setting.     

Segmental Liver Transplantation from Non-Heart Beating Donors—An Early Experience with Implications for the Future

We report our experience of pediatric liver transplantation with partial grafts from non-heart beating donors (NHBD). Controlled donors less than 40 years of age with a warm ischemia time (WI) of less than 30 min were considered for pediatric recipients. Death was declared 5 min after asystole. A super-rapid recovery technique with aortic and portal perfusion was utilized. Mean donor age was 29 years and WI 14.6 min (range 11–18). Seven children, mean age 4.9 years (0.7–11), median weight 20 kg (8.4–53) received NHBD segmental liver grafts. Diagnoses included seronegative hepatitis, neonatal sclerosing cholangitis, familial intrahepatic cholestasis, hepatoblastoma, primary hyperoxaluria and factor VII deficiency (n = 2).The grafts included four reduced and one split left lateral segments, one left lobe and one right auxiliary graft. Mean cold ischemia was 7.3 h (6.2–8.8). Complications included one pleural effusion and one biliary collection drained percutaneously. At 20 months (10–36) follow-up all children are alive and well with functioning grafts.
Donation after cardiac death is a significant source of liver grafts for adults and children with careful donor selection and short cold ischemic times.     

The effects of altering time delays of coupled pacing during acute atrial fibrillation

BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied.     

Can Electrocardiographic Criteria Predict Adverse Cardiac Events and Positive Cardiac Markers?

OBJECTIVES: To determine electrocardiogram (ECG) predictors of positive cardiac markers and short-term adverse cardiac events in an undifferentiated chest pain population presenting to emergency departments (EDs). The authors hypothesized that specific ECG findings, other than those previously identified in higher-risk populations, would be predictive of cardiac outcomes and positive cardiac markers. METHODS: This study used data from a prospectively collected, retrospectively analyzed Internet-based data registry of undifferentiated chest pain patients (i*trACS). Logistic regression modeling was performed to determine the ECG findings that were predictive of 1) positive cardiac markers and 2) short-term adverse cardiac events. RESULTS: ST-segment elevation (STE), ST-segment depression (STD), pathological Q-waves (PQW), and T-wave inversion were associated with increased odds of percutaneous coronary intervention or catheterization, myocardial infarction, or coronary artery bypass grafting. The odds of creatine kinase-MB (CK-MB) measuring positive were increased if STE, STD, or PQW were present [odds ratio (OR) 2.495, 2.582, and 1.295, respectively]. A right bundle branch block tended to decrease the odds of CK-MB measuring positive (OR 0.658). A similar pattern of results was observed for troponin I (OR 3.608 for STE, 3.72 for STD, 1.538 for PQW). Troponin T showed an increased odds of measuring positive if any of STE, STD, left bundle branch block, or T-wave inversion were evident (OR 2.313, 2.816, 1.80, and 1.449, respectively). CONCLUSIONS: Initial ECG criteria can be used to predict short-term cardiac outcomes and positive cardiac markers. These findings can be important aids in the risk-stratification and aggressive treatment regimens of chest pain patients presenting to EDs.     

快速心房起搏对家兔L-型钙通道和Kv4.3钾通道基因表达的影响

目的观察快速心房起搏对家兔心房L型钙通道亚单位和Kv4.3钾通道基因表达的影响。方法新西兰大耳白家兔36只,随机分成6组,经右颈外静脉穿刺置入电极于右房,分别给予0、3、6、12、24或48h快速心房起搏,停止起搏后取右房组织,应用半定量反转录聚合酶链式反应测定各时相点L型钙通道α1c,β1,α2亚单位,钾通道Kv4.3mRNA的表达水平。结果L型钙通道α1c、β1亚单位在快速起搏6h后表达水平下调,并随着起搏时间的延长进一步下调。α2亚单位的mRNA表达在各时相点无显著差异。Kv4.3的mRNA的表达在快速起搏的24h和48h下降分别达55.50%（P<0.01）和59.12%（P<0.01）。48h后下降达到一个平台期。结论快速心房起搏可导致L型钙通道亚单位和Kv4.3钾通道mRNA表达下调。     

定量组织速度成像对右室起搏患者左室收缩运动的研究

目的　应用定量组织速度成像 (QTVI)评价右室心尖起搏 (RVAP)VVI型对左心收缩功能的影响。方法　应用GEVivid 7彩色多普勒超声显像仪对 2 0例RVAP患者和 2 0例正常人的心尖四腔切面的室间隔和左室外侧壁速度和位移曲线进行观察 ,测量心电图Q波分别至室间隔和左室外侧壁收缩期峰速度的时间 ,并除以R R间期进行校正。结果　QTVI显示右室起搏器置入者的室间隔与左室外侧壁速度曲线的收缩期S波非同步出现。Q波至室间隔收缩期峰速度的时间短于Q波至左室外侧壁收缩期峰速度的时间 ,两者分别为 ( 0 .12± 0 .0 2 )s和 ( 0 .14± 0 .0 2 )s,P <0 .0 5。结论　右室起搏后早期的左室整体收缩功能虽未见明显下降 ,但QTVI可以发现室间隔与左室壁收缩明显的不协调 ,可作为早期分析左室收缩运动的定量方法。     

Monoclonal Antibody Specific for TIRC7 Induces Donor-specific Anergy and Prevents Rejection of Cardiac Allografts in Mice

T cell immune response c-DNA (TIRC7) is up-regulated during the early stages of T-cell activation in response to alloantigens. In this study, we analyzed the effects of newly developed monoclonal antibodies (mAb) against TIRC7 in acute cardiac allograft rejection. Fully vascularized heterotopic allogeneic heart transplantation was performed in mice across a full-mismatch barrier (C57Bl/10 into CBA). Recipients received seven injections (day 0-7) of a novel anti-TIRC7 mAb or remained untreated. Graft survival, histology and ex vivo lymphocyte functions were tested. Targeting of TIRC7 with an anti-TIRC7 mAb diminishes lymphocyte infiltration into grafts resulting in delay of morphological graft damage and prolongation of allograft survival. The lymphocytes from anti-TIRC7 mAb-treated animals exhibit hypo-responsiveness without evidence of lymphocyte depletion against the donor allo-antigens. Proliferation and expression of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) were down-regulated while interleukin-4 (IL-4) and IL-10 expression were spared. Moreover, anti-TIRC7 mAb enhanced up-regulation of CTLA-4 expression but suppressed up-regulation of CD25 on stimulated lymphocytes in vitro and in vivo. Ligation of TIRC7 has important effects on the regulation of co-stimulatory signaling pathways associated with suppressing of T-cell activation. Targeting of TIRC7 may therefore provide a novel therapeutic approach for modulating T cell immune responses during organ transplantation.     

情绪波动对急性心肌梗死后心律失常和心力衰竭的影响

目的回顾性探讨情绪波动对急性心肌梗死后心律失常、休克和心力衰竭的影响 ,为针对性地护理提供理论依据。方法将 2 4 1例急性心肌梗死病人有情绪波动 15 6例为观察组 ,无情绪波动 85例为对照组 ,比较情绪波动与心律失常、休克和心力衰竭的关系。结果观察组心律失常的发病率比对照组明显增高 (P <0 .0 1) ,差异有显著性意义。并得出相对危险度 (RR) =1.6 3,归因危险度 (AR) =2 9.12 % ,归因危险比数 (ARP) =38.83% ;室性期前收缩发病率比对照组明显增高 (P <0 .0 1) ,差异有显著性意义 ,并得出RR =2 .2 9,AR =2 6 .5 0 % ,ARP =5 6 .37%。结论情绪波动可使急性心肌梗死后心律失常 ,特别是室性期前收缩的发病率增高。