阵发性心房颤动射频消融术后左房大小和机械功能变化

目的探讨经导管射频消融术对阵发性心房颤动（房颤）患者左房功能的影响,并比较肺静脉口节段性电隔离（SPVI）和环肺静脉消融（CPVA）两种术式在此方面的异同。方法66例阵发性房颤患者接受射频消融手术治疗。应用经胸心脏超声检查测量患者术前、术后1天、1个月和3个月时的左房前后径、左房面积、舒张晚期跨二尖瓣血流峰速（A峰）和舒张晚期心肌组织运动峰速（A’峰）。结果66例患者中,30例接受SPVI术,36例接受CPVA术。两组患者一般临床情况及术前超声参数相似。术后随访（315±153）d,SPVI组和CPVA组无房性心律失常复发率相似（70％与75％,P=0．650）。两组在手术后左房面积均较术前缩小,SPVI组发生于术后1个月,而CPVA组于术后3个月。SPVI组左房直径也显示出明显缩小（P〈0．05）,而CPVA组术前和术后则差异无统计学意义。左房机械功能方面,CPVA组于术后1天A峰和A’峰明显降低（P〈0．05）,两者均于3个月后较术后1天明显回升,A峰恢复至术前水平,A’峰较术前有明显升高。SPVI组术后1天没有出现A峰和A’峰明显降低;其A峰于术后1个月升高,并保持至3个月;A’峰于术后3个月时升高。结论阵发性房颤经导管SPVI术和CPVA术治疗后3个月,可以出现左房面积缩小和收缩功能改善。CPVA术比SPVI术造成了更多的左房损伤,表现为术后1天左房功能的下降以及术后左房大小、功能参数改善的延迟。     

PCI对冠心病合并左心舒张功能不全患者心功能的影响

目的：探讨冠状动脉介入（ PCI）改善冠心病患者心脏舒张功能不全的临床价值。方法选取冠心病合并左心舒张功能不全而左心射血分数正常患者48例,随机分成观察组和对照组各24例。两组均行常规药物治疗,在此基础上观察组行PCI治疗。两组治疗前及治疗后1、3、6个月采用超声心动图测量心脏等容舒张时间（IVRT）、舒张早期及晚期二尖瓣血流频谱E峰与A峰比值（E／A）、肺静脉血流反流速度（Ar）,治疗后6个月评价临床疗效。结果治疗后6个月随访,两组总有效率差异有统计学意义（P＜0．05）。与对照组比较,观察组治疗后1、3、6个月IVRT缩短,E／A升高,Ar降低,差异均有统计学意义（P＜均0．05）。结论 PCI治疗能明显改善冠心病合并左心舒张功能不全患者的心脏功能。     

冠状动脉旁路术与左心室功能关系研究

目的研究冠状动脉旁路术（CABG）术前与术后早期左室功能的变化,并找出其影响因素。方法 103例行CABG术患者,应用心脏彩色多普勒超声测定其术前及术后4～7 d左室射血分数（LVEF）、缩短分数（FS）及二尖瓣血流E峰与A峰的比值（E/A）。结果术后LVEF值、FS值较术前减低（P〈0.01）;术前LVEF值、术前FS值、左前降支狭窄程度、NYHA心功能分级是影响左室功能下降的主要因素。结论 CABG术后早期可出现左室收缩功能下降,为缺血再灌注后的心肌顿抑现象,应积极加以治疗。     

心脏再同步化治疗后心脏结构和功能改变的临床分析

目的：比较心脏再同步化治疗（CRT）后心脏结构和功能的变化,以评估CRT植入对EF降低的慢性心力衰竭（HFrEF）患者的疗效。方法：纳入2017年1月1日至2017年12月31于陆军军医大学第二附属医院心血管内科就诊的HFrEF患者,患者有行CRT指征且同意行CRT,并无CRT植入的相关禁忌症,入院后择期行CRT植入术。患者分别于术前、术后3月、6月行心脏超声检测。测定舒张期心脏各腔室大小,左室射血分数（LVEF）,左室短轴缩短率(FS),每搏输出量（SV）。二尖瓣反流、三尖瓣反流、反流压差等参照指南推荐进行,并比较不同时间点上述各参数的变化。结果：87例患者符合纳入标准,其中15例患者符合排除标准,72例患者行CRT植入术,68例成功完成CRT,纳入本组研究。CRT术后心脏各腔室大小较术前均显著下降（P < 0.05）,术后EF、FS、SV较术前均显著增加（P < 0.05）,术后二尖瓣返流程度、三尖瓣反流程度及三尖瓣反流压差较术前均显著降低（P < 0.05）。结论：CRT可显著改善伴有心脏收缩不同步的HFrEF患者的心脏结构和功能。     

单双极射频消融改良迷宫术用于瓣膜病合并心房颤动的疗效

目的：探讨单极与双极射频消融改良迷宫术在心脏瓣膜手术中治疗心房颤动（房颤）的疗效及安全性. 方法：连续入选2010年1月至2012年12月在我院行心脏瓣膜手术,同期行射频消融改良迷宫术的患者137例.根据射频消融系统的不同,分为单极射频消融组（n=56）及双极射频消融组（n=81）.比较两组患者术中射频消融时间、围术期严重并发症的发生率及死亡率、术后房颤消除率及心功能等临床指标. 结果：两组围术期严重并发症的发生率及死亡率无统计学差异.术中两组消融所需时间亦无统计学差异.两组患者术后1年的心功能分级均较术前改善,左房内径明显减小（P＜0.01）.与单极消融组相比,双极消融组同期的房颤消除率显著提高（P＜0.05）. 结论：心脏瓣膜手术同期行射频消融迷宫术是治疗心脏瓣膜疾病合并房颤安全、有效的方法.与单极射频消融相比,双极射频消融的房颤消除率更高,具有较好的临床应用价值.     

围术期老年糖尿病患者心率变异性的监测及临床意义

目的探讨围术期老年糖尿病患者非心脏手术后心脏自主神经功能的变化及意义。方法选择择期非心脏手术的老年患者160例分为糖尿病组（DM组,78例）和非糖尿病组（NDM组,82例）。用动态心电图监测仪分别记录术前（患者入院后）、术后第1天（从手术开始记录）、术后第2天（第2个24h）的心率变异性（HRV）,包括SDNN、SDANN和RMSSD。结果术前与NDM组比较,DM组SDNN、SDANN降低（P〈0．01）,RMSSD差异无统计学意义;术后第1天DM组SDNN、SDANN、RMSSD均低于术前（P〈0．05）,NDM组SDNN、SDANN低于术前（P〈0．05）,RMSSD与术前相比差异无统计学意义;术后第2天两组各指标均低于术前及术后第1天（P〈0．01）;DM组低于NDM组。结论麻醉、手术创伤及术后疼痛对患者的自主神经功能有显著的影响。与非糖尿病患者相比,糖尿病患者手术后发生自主神经功能紊乱更为严重。     

心脏恶液质患者手术后早期连续性肾脏替代疗法治疗效果观察

目的总结术后早期连续性肾脏替代（CRRT）疗法改善心脏恶液质患者心脏功能的临床经验。方法17例心脏恶液质患者于瓣膜置换术后接受CRTT治疗。术前心功能分级（NYHA）Ⅲ级11例、Ⅳ级6例。手术后应用常规方法处理后血流动力学仍不稳定,行CRRT治疗。记录CRRT前后左房压（LAP）、平均动脉压（MAP）、左室射血分数（LVEF）及血清B型钠尿肽（BNP）水平变化。结果 1例于术后第8天死于多脏器功能衰竭。16例存活患者随访1～6个月,心功能Ⅰ级6例、Ⅱ级8例、Ⅲ级2例;CRRT 48 h后LAP明显下降,72 h后超声检查提示心脏收缩有力,EF明显提高;心脏超声检查示左房内径及左室舒张末内径明显缩小,LVEF明显提高。结论手术后早期应用CRRT可降低心脏负荷,减少心脏做功,有效改善心脏恶液质患者的心脏功能。     

慢性心力衰竭合并持续性心房颤动患者心脏再同步治疗术后房室结消融及药物控制心室率疗效观察

目的观察慢性心力衰竭合并持续性心房颤动（房颤）患者心脏再同步治疗（CRT）的疗效,比较房室结消融术及药物控制心室率两种方法疗效的差异。方法慢性心力衰竭合并持续性房颤患者,符合CRT植入适应证并接受CRT或心脏再同步治疗除颤器（CRT—D）植入术,术后随机分为两组,房室结消融组以及药物治疗组,术后随访观察患者临床症状及心功能改善等情况,比较两组的疗效。结果共人选了26例患者,其中房室结消融组14例,药物控制组12例。术前两组患者间心功能,左心室舒张末期内径（LVEDD）,左心室射血分数（LVEF）及用药等基本情况差异无统计学意义。CRT术后随访结果,房室结消融组双心室起搏比例100％,药物治疗组双心室起搏比例72．0％±9．7％。与药物治疗组相比,房室结消融组LVEDD略有缩小[（61．0±6．9）mm对（62．0±7．8）mm],但差异无统计学意义（P=0．08）,LVEF改善明显（0．41±0．06对0．35±0．04）,差异有统计学意义（P=0．04）,提示房室结消融组疗效更佳。结论对慢性心力衰竭合并持续性房颤患者,CRT可以改善患者心功能,CRT术后行房室结消融可以提高有效的双心室起搏比例,进一步提高CRT疗效。     

非胰岛素依赖型糖尿病病人心脏功能的改变

经静注潘生丁锝－９９ｍ标记的甲氧基异丁基异腈心肌断层显像术筛选后，用核素心室造影术评价非胰岛素依赖型糖尿病（ＮＩＤＤＭ）病人组１８例及对照组１６例在静息及极量运动状况下的心脏收缩功能变化；以多普勒超声心动图评价静息时心脏舒张功能改变。结果：静息状态下ＮＩＤ－ＤＭ组心率虽快于对照组，射血分数（ＥＦ）、峰射血率（ＰＥＲ）与对照组无差异；极量运动时则ＰＥＲ有统计学意义地明显低于对照组，且有４例ＥＦ较运动前降低＞５％，对照组无此现象，此差异接近显著意义（Ｐ＝０．０６５）．静息时ＮＩＤＤＭ组的Ｅ／Ａ比值降低，等容舒张时间延长，揭示ＮＩＤＤＭ病人心室收缩贮备功能降低，舒张功能在静息时已异常。     

不同起搏模式对病态窦房结综合征患者心功能长期影响的探讨

目的前瞻性观察不同起搏模式对心功能长期的影响并探讨可能机制。方法 185例病态窦房结综合征（SSS）患者均采用常规方法经锁骨下静脉途径成功置入永久双腔心脏起搏器,术后即刻程控起搏器,根据SAS软件的PROC程序产生一组随机序列分为AAI（92例）及DDD（93例）起搏组。采用心脏超声观察术前,术后1、2、5年左室舒张末容积（LVEDV）、左室收缩末容积（LVESV）及左室射血分数（LVEF）的变化,比较两种起搏模式对左心功能的影响;术后1、2及5年进行随访结合起搏器程控记录房颤发生并记录DDD起搏组右室起搏百分比（VP%）,探讨VP%与心功能变化及房颤发生的关系。结果 AAI起搏组术前,术后1、2、5年随访LVEDV,LVESV及LVEF比较差异无统计学意义（P〉0.05）,DDD起搏组术前、术后1、2、5年LVEDV差异无统计学意义（P〉0.05）,术后5年LVESV（60.33±13.28）ml较术后1、2年增加,差异有统计学意义（F=2.7388,P〈0.05）,术后5年LVEF（41.75±8.74）%较术前、术后1、2年明显降低,差异有统计学意义（F=33.4393,P〈0.05）;AAI组与DDD组房颤的发生差异有统计学意义（P〈0.05）。术后5年DDD组中〈50%VP%,组中出现房颤患者为3例,≥50%VP%组中出现房颤患者为15例,两组之间房颤的发生率差异有统计学意义（P〈0.05）。结论在DDD起搏模式下,高的VP%可对患者的左心功能造成损害并增加房颤的发生。对于不合并房室传导阻滞的SSS患者,AAI起搏较DDD起搏能使患者更受益。     

Reduced-energy diet improves survival of obese KKAy mice with viral myocarditis: induction of cardiac adiponectin expression

Obesity is an important risk factor for heart disease. Whether weight loss affects the severity of heart failure induced by viral myocarditis is a matter of debate. We hypothesized that weight loss could improve cardiac dysfunction by inducing cardiac expression of a cardioprotective cytokine, adiponectin. We examined the relationship between weight loss by food restriction and heart failure due to viral myocarditis in obese KKAy mice. We intraperitoneally injected encephalomyocarditis virus (500 plaque-forming units/mouse) into KKAy mice fed ad libitum as a control (CF) or 60% restriction of that eaten by ad libitum (RF). The 14-day survival rate was 0% in FF, whereas it was 23% in RF (P<0.01). Heart weight/body weight ratio in RF was lower than that in FF on day 5 after viral inoculation (P<0.05). Histological scores for myocardial necrosis and inflammation on day 5 were significantly lower in RF than in FF (P<0.05). Circulating adiponectin level on day 0 was significantly elevated in RF compared with that in FF (32+9 vs. 22+2 microg/mL, P<0.05). Comparative expression of cardiac adiponectin mRNA in RF was significantly higher than that in FF (5.1+0.3 vs. 1+0.2, P<0.05). Cardiac tumor necrosis factor-alpha (TNF-alpha) mRNA in RF was significantly decreased compared with that in FF on day 5 (P<0.05). Cardiac expression of nuclear factor kappa B was reduced and that of peroxisome proliferator-activated receptor gamma mRNA was increased in RF in comparison with FF on day 0. Cardiac adiponectin mRNA was negatively correlated with cardiac TNF-alpha mRNA (r=-0.555; P=0.0097). Weight loss improved the survival and myocardial damage in obese mice with viral myocarditis, with cardiac induction of adiponectin. The induction of adiponectin might provide benefit through a cardioprotective effect against acute heart failure due to viral myocarditis in obese subjects.     

Predictors and early and late outcomes of respiratory failure in contemporary cardiac surgery

BACKGROUND: Respiratory failure (RF) is a serious complication following heart surgery. The profile of patients referred for cardiac surgery has changed during the last decade, making prior investigations of RF after cardiac surgery less relevant to the current population. This study was designed to analyze the incidence, predictors of RF, and early and late outcomes following this complication in a large contemporary cardiac surgery population. METHODS: We retrospectively analyzed prospectively collected data from the New York State Department of Health database including 5,798 patients undergoing cardiac surgery between January 1998 and December 2005. Patients with RF (intubation time > or = 72 h) were compared to patients without RF. RESULTS: The incidence of RF was 9.1% (n = 529). The highest incidence of RF was observed following combined valve/coronary artery bypass graft (14.8%) and aortic procedures (13.5%). Multivariate analysis revealed preoperative and operative predictors of RF such as renal failure (odds ratio [OR], 2.3), aortic procedures (OR, 2.6), hemodynamic instability (OR, 3.2), and intraaortic balloon pump (OR, 2.6). The mortality rate following RF was 15.5% (n = 82), compared to 2.4% (n = 126) in the no-RF group (p < 0.001). Kaplan-Meier survival curves showed significantly poorer survival among RF patients (p < 0.001) compared to the no-RF group. CONCLUSION: RF remains a serious and common complication following cardiac surgery, particularly in patients undergoing complex procedures. RF is associated with significant comorbidity, increased hospital mortality, and reduced long-term survival. Future research efforts should focus on a more precise identification of patients at risk and the development of new treatment modalities that would potentially prevent the occurrence of this complication.     

Aspirin-induced platelet inhibition in patients undergoing cardiac surgery

Platelet function and response to pharmacological inhibition are altered by cardiac surgery. For example, aggregation is increased early after aortic valve replacement (AVR) and platelet response to aspirin is often insufficient after coronary artery bypass grafting (CABG). We hypothesized that the effect of aspirin administration after cardiac surgery might be impaired due to platelet activation. Therefore, the antiplatelet effect of aspirin was compared in patients (n = 20 per group) after CABG and AVR surgery (bileaflet prosthesis). Arachidonic acid-induced aggregation (turbidimetry) and thromboxane formation (radioimmunoassay) were determined before and 1, 5, and 10 days after surgery. In CABG-patients, antiplatelet treatment had been discontinued 10 days before surgery. Oral aspirin was started on day 1 after CABG. AVR-patients did not receive oral aspirin. Before surgery, platelet aggregation and thromboxane formation were significantly higher in patients with aortic stenosis. After CABG, thromboxane formation was not significantly changed from control values before surgery (66 +/- 13% on day 10) despite oral aspirin treatment, whereas thromboxane formation in patients undergoing AVR significantly increased compared to values before surgery (216 +/- 29% on day 10). In both groups of patients, 100 micromol/l aspirin in vitro largely inhibited platelet function before surgery, with markedly attenuated effects after surgery. In conclusion, thromboxane formation increased after AVR but not after CABG. The antiplatelet effect of aspirin, therefore, may be impaired after CABG by increased platelet activity. An additional in vitro "resistance" of platelets was seen after both CABG and AVR.     

Aspirin-induced platelet inhibition in patients undergoing cardiac surgery

Platelet function and response to pharmacological inhibition are altered by cardiac surgery. For example, aggregation is increased early after aortic valve replacement (AVR) and platelet response to aspirin is often insufficient after coronary artery bypass grafting (CABG). We hypothesized that the effect of aspirin administration after cardiac surgery might be impaired due to platelet activation. Therefore, the antiplatelet effect of aspirin was compared in patients (n?=?20 per group) after CABG and AVR surgery (bileaflet prosthesis). Arachidonic acid-induced aggregation (turbidimetry) and thromboxane formation (radioimmunoassay) were determined before and 1, 5, and 10 days after surgery. In CABG-patients, antiplatelet treatment had been discontinued 10 days before surgery. Oral aspirin was started on day 1 after CABG. AVR-patients did not receive oral aspirin. Before surgery, platelet aggregation and thromboxane formation were significantly higher in patients with aortic stenosis. After CABG, thromboxane formation was not significantly changed from control values before surgery (66?±?13% on day 10) despite oral aspirin treatment, whereas thromboxane formation in patients undergoing AVR significantly increased compared to values before surgery (216?±?29% on day 10). In both groups of patients, 100?µmol/l aspirin in vitro largely inhibited platelet function before surgery, with markedly attenuated effects after surgery. In conclusion, thromboxane formation increased after AVR but not after CABG. The antiplatelet effect of aspirin, therefore, may be impaired after CABG by increased platelet activity. An additional in vitro “resistance” of platelets was seen after both CABG and AVR.     

Characteristics of patients with improvement or worsening in renal function during treatment of acute decompensated heart failure

Worsening renal function (RF) and improved RF during the treatment of decompensated heart failure have traditionally been thought of as hemodynamically distinct events. We hypothesized that if the pulmonary artery catheter-derived measures are relevant in the evaluation of cardiorenal interactions, the comparison of patients with improved versus worsening RF should highlight any important hemodynamic differences. All subjects in the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness trial limited data set with admission and discharge creatinine values available were included (n = 401). No differences were found in the baseline, final, or change in pulmonary artery catheter-derived hemodynamic variables, inotrope and intravenous vasodilator use, or survival between patients with improved versus worsening RF (p = NS for all). Both groups were equally likely to be in the bottom quartile of cardiac index (p = 0.32), have a 25% improvement in cardiac index (p = 0.97), or have any worsening in cardiac index (p = 0.90). When patients with any significant change in renal function (positive or negative) were compared to those with stable renal function, strong associations between variables such as a reduced cardiac index (odds ratio 2.2, p = 0.02), increased intravenous inotrope and vasodilator use (odds ratio 2.9, p <0.001), and worsened all-cause mortality (hazard ratio 1.8, p = 0.01) became apparent. In contrast to traditionally held views, the patients with improved RF and those with worsening RF had similar hemodynamic parameters and outcomes. Combining these groups identified a hemodynamically compromised population with significantly worse survival than patients with stable renal function. In conclusion, the changes in renal function, regardless of the direction, likely identify a population with an advanced disease state and a poor prognosis.     

Radiofrequency catheter ablation and nerve growth factor concentration in humans

BACKGROUND: In animal models, expression of nerve growth factor (NGF) is increased after necrotic myocardial injury. Whether radiofrequency (RF) catheter ablation increases NGF expression in humans is unclear. OBJECTIVES: The purpose of this study was to determine NGF concentrations in the aorta, coronary sinus, and peripheral veins before and after RF ablation in patients. METHODS: We sampled blood from aorta and either great cardiac vein (group 1, N = 18) or proximal (group 2, N = 20) coronary sinus before and after RF ablation. In group 3 (N = 21), peripheral venous blood was sampled before and after RF ablation and then up to postoperative day 7. In group 4 (N = 10), we sampled peripheral venous blood during diagnostic electrophysiologic study. The NGF concentration was determined by enzyme-linked immunosorbent assay. Transcardiac NGF concentration was the difference in NGF concentrations between coronary sinus and aorta. RESULTS: There was no change in transcardiac NGF concentrations in groups 1 and 2. In group 3, the NGF level did not change significantly from before the procedure (17.10 +/- 15.80 ng/mL) to immediately after the procedure (14.46 +/- 10.36 ng/mL). However, NGF levels increased significantly to 31.24 +/- 19.82 ng/mL (N = 21, P <.0001) on postoperative day 1, 26.23 +/- 16.89 ng/mL (N = 20, P <.001) on postoperative day 2, and 22.01 +/- 11.35 ng/mL (N = 16, P = .003) on postoperative day 3. NGF concentrations did not change significantly in group 4. CONCLUSION: RF ablation did not result in a detectable increase of transcardiac NGF concentration immediately after the procedure. However, the systemic NGF concentration increased significantly on postoperative days 1 to 3, suggesting that RF ablation resulted in increased NGF expression.     

Ischaemia modified albumin in radiofrequency catheter ablation.

Aim Ischaemia modified albumin (IMA) is considered a marker of myocardial ischaemia, in contrast to the biomarkers of myocardial injury [creatine kinase (CK), the MB isoenzyme of CK, and cardiac troponin I (Tn-I)] that are released when cardiac necrosis occurs. Ischaemia modified albumin has been reported to increase following percutaneous coronary intervention and in acute coronary syndromes. We sought to determine whether IMA increases following radiofrequency (RF) ablation. METHODS AND RESULTS: We studied 40 consecutive patients who underwent RF catheter ablation; 20 were men and 20 women and their age was 47 +/- 16 (16-77) years. All patients underwent electrophysiological study and subsequent RF ablation. Peripheral venous samples were collected before the procedure (baseline), immediately after the procedure, 2 h post-procedure and the following day (20 h post-procedure) and assayed for CK, the MB isoenzyme of CK, cardiac Tn-I and IMA. Ischaemia-modified albumin plasma levels did not differ significantly at all four time points, baseline, and following ablation (P = 0.5974), whereas CK, CK-MB, and Tn-I increased significantly at all time points compared with baseline (P < 0.0001). Post-ablation, all but three 3 CK measurements were in the normal range; 14 patients had CK-MB plasma levels above the upper limit of normal; all but one patient had Tn-I elevated. CONCLUSION: The IMA plasma levels do not change significantly following RF ablation, unlike biomarkers of myocardial injury, implying that myocardial necrosis occurs without preceding ischaemia.     

Myocardial contrast echocardiography versus Thrombolysis In Myocardial Infarction score in patients presenting to the emergency department with chest pain and a nondiagnostic electrocardiogram

OBJECTIVES: We hypothesized that regional function (RF) and myocardial perfusion (MP) are superior to the Thrombolysis In Myocardial Infarction (TIMI) score for diagnosis and prognostication in patients presenting to the emergency department (ED) with chest pain (CP) and a nondiagnostic electrocardiogram. BACKGROUND: Rapid diagnosis and prognostication is difficult in patients presenting to the ED with suspected cardiac CP. METHODS: Contrast echocardiography was performed to assess RF and MP on 957 patients presenting to the ED with suspected cardiac CP and a nondiagnostic electrocardiogram. A modified TIMI (mTIMI) score was calculated from six immediately available variables. A full TIMI score also was derived after troponin levels were able to be accessed adequately. Follow-up was performed for early (within 24 h), intermediate (30 day), and late primary (death and myocardial infarction) or secondary (unstable angina and revascularization) events. RESULTS: The mTIMI score was unable to discriminate between intermediate- compared to high-risk patients at any follow-up time point, whereas only 2 of 523 patients with normal RF had an early primary event. Regional function provided incremental prognostic value over mTIMI scores for predicting intermediate and late events. In patients with abnormal RF, MP further classified patients into intermediate- and high-risk groups. The full TIMI score could not improve upon these results at any follow-up time point. CONCLUSIONS: Contrast echocardiography can rapidly and accurately provide short-, intermediate-, and long-term prognostic information in patients presenting to the ED with suspected cardiac CP even before serum cardiac markers are known. Integrating contrast echocardiography into the ED evaluation of CP may improve the risk stratification of such patients.     

Dysfunction of pre- and post-operative cardiac autonomic nervous system in elderly patients with diabetes mellitus

The pre- and post-operative cardiac autonomic nervous functions were compared in elderly, non-cardiac surgery patients with diabetes mellitus (DM) and without diabetes mellitus (NDM). A group of 30 unpremedicated elderly patients scheduled to undergo elective non-cardiac surgery were studied, including 15 DM patients and 15 NDM patients. Each component of heart rate variability (HRV) analysis in the frequency domain was monitored with Holter during the nights of the day before and on 1st and 2nd day after operation. After surgery, total power (TP), high frequency (HF), low frequency (LF) and very low frequency (VLF) significantly decreased as compared to the baseline values before operation in both groups (p < 0.05). The LF/HF ratio was significantly changed in DM group but did not change in NDM group. On the 2nd postoperative day, TP, HF, LF and VLF in DM group were further decreased as compared to those on the 1st postoperative day and were significantly lower than those in NDM group (p < 0.01 or 0.05), but these indices in NDM group did not show significant decreases. Surgery induced the cardiac autonomic nervous dysfunction in elderly patients not only with DM but also without diabetes. On the 2nd postoperative day, the disturbances of cardiac autonomic nervous activity were more sever in DM patients, compared to the 1st postoperative day, but was not significantly more sever than in the NDM patients.     

Growth hormone alone or combined with metoprolol preserves cardiac function after myocardial infarction in rats.

BACKGROUND AND OBJECTIVE: Beta-adrenoreceptor blocking agents are important for the treatment of myocardial infarction (MI). Accumulating evidence also indicates that growth hormone (GH) improves cardiac function after MI in rats. We aimed to investigate the cardiovascular effects of combined treatment in an animal model of MI. METHODS: MI was induced in rats by ligation of the left coronary artery. Three days after MI, animals were randomly assigned to one of four groups: controls (C) (n=19); GH (n=19) receiving s.c. 2 mg/kg per day rhGH; metoprolol (M) group (n=19) receiving 24 mg/kg per day and combined group (GHM) (n=20) treated with both GH (2 mg/kg per day s.c.) and M (24 mg/kg per day) for 9 days. Transthoracic echocardiography was performed before and after treatment. RESULTS: Serum levels of insulin-like growth factor I were significantly elevated in the GH-group but not in the GHM group compared to controls. Left ventricular volumes, cardiac index, systolic blood pressure, were similar in all groups. Percent changes in ejection fraction compared to baseline were; GH (6.1+/-5.0%) and GHM (6.1+/-4.2%) vs. C (-12.5+/-3.0%), P<0.01, M (-7.3+/-4.2%). The occurrence of aneurysms was not significantly different between the various treatment regimes. CONCLUSION: Treatment with growth hormone alone or in combination with metoprolol preserved left ventricular function after MI.