左西孟旦对左室功能低下的心脏手术患者的作用

背景左室功能低下的患者体外循环手术后常需要立即给予正性肌力药支持。左西孟旦能改善心功能，其作用机制不同于现有药物。我们推测，对心室功能严重受损的患者，使用左西孟旦比使用增加心肌耗氧的正性肌力药，更有助于手术后心功能的恢复。方法30例手术前射血分数≤30％，拟行择期体外循环心脏手术的患者，随机分配到两个药物实验组：开放主动脉后立即分别给予米力农0．5mg·kg^-1·min^-1或左西孟旦0．1mg·kg^-1·min^-1.观察者不清楚患者用药种类。所有患者均给予多巴酚丁胺5mg·kg^-1·min^-1。结果手术后两组最初每搏输出量相似。但12小时后，尽管两组充盈压接近，米力农组每搏输出量下降，而左西孟旦组无下降（组间P〈0．05）。左西孟旦组正性肌力药。息剂量、用药持续时间和去甲肾上腺素的用量均少于米力农组（P〈0．05），且气管插管持续时间也较短（P=0008）。手术后30天内，米力农组有3例患者死亡，而左西孟旦组无一例死亡。结论对于手术前射血分数低下的心脏手术患者，手术后合用多巴酚丁胺与左西孟旦比合用多巴酚丁胺与米力农，能更好地维持心搏出量。     

新型正性肌力药——左西孟旦

左西孟旦是钙离子增敏剂,并对KATP通道产生作用。它增强心肌收缩力而不增加心肌耗氧量;它还引起冠状动脉和体血管扩张。其药代动力学特点在健康人和在充血性心衰病人中相似。左西孟旦主要用于失代偿性急性心力衰竭和心肌顿抑。现就其药理学和临床应用效果作一综述。     

新型正性肌力药左西孟旦的作用机制及临床应用

左西孟旦是一种新型正性肌力药--钙增敏剂,可通过钙敏作用增强心肌收缩力,激活K+通道使血管扩张,且并不增加心肌氧耗和心率,因而具有改善心功能和心肌保护等作用.可应用于治疗急性失代偿心力衰竭、心肌缺血后心脏收缩力异常、心肌顿抑以及用于心脏手术期间循环的调控等方面.     

正性肌力药在体外循环手术中应用存在的问题及对策

背景 正性肌力药广泛应用于围手术期,特别是心脏、大血管手术中,是进行循环支持的有效手段. 目的 就正性肌力药在CPB手术中应用存在的问题及对策进行探讨,以提高临床用药合理性. 内容 从药物作用机制的角度简单介绍目前临床上应用较广的各类正性肌力药作用特点,分析这些药在CPB手术中应用存在的问题,并提出对策. 趋向 合理应用传统正性肌力药,同时大力开发更安全、更有效的新型正性肌力药,摸索出CPB手术围手术期更好的正性肌力药应用方案.     

左西孟旦在重症瓣膜病术中缺血预处理中的应用分析

目的观察左西孟旦在重症瓣膜病术中缺血预处理中的应用。方法重症心脏瓣膜病病人30例,采用随机方法分为两组,预处理组15例,于麻醉开始即静脉泵入左西孟旦,剂量为每分钟0.1～0.2μg/kg,维持用药24小时;对照组15例,未使用左西孟旦。观察两组病人手术中麻醉情况、体外循环(CBP)停机过程和ICU恢复情况。结果病人均顺利实施瓣膜手术,其中预处理组1例病人术后并发呼吸功能衰竭、肺部感染、多器官功能衰竭死亡,对照组1例病人抗凝后并发脑出血、多器官功能衰竭死亡,其余病人均康复出院。预处理组和对照组30天死亡率分别为6.7%和6.7%,CBP时间分别为(114.43±23.3)分钟和(138.7±20.2)分钟,呼吸机辅助时间分别为(31.2±10.3)小时和(23.00±11.0)小时,ICU时间分别为(116+56.5)小时和(92.13±54.5小时,术后LVEF分别为(48.29±8.2)%和(49.63±7.92)%,术后肌酐分别为(119.43±18.1)μmol/L和(113.75±10.3)μmol/L,术后BNP分别为(8682.0±443.05)pg/ml和(4677.25±207.74)pg/ml,术后心胸比分别为(0.67±0.08)和(0.63±0.06),两组比较差异无统计学意义(P0.05)。二组病人心肌组织中细胞色素C、Caspase-9、Caspase-3的蛋白含量比较,差异无统计学意义(P0.05)。用药组在术后1周LVEF得到改善(40.1±10.0)和(48.29±8.2),差异有统计学意义(P值0.05)。两组病人不同时间点炎症因子比较,差异无统计学意义(P0.05)。结论重症瓣膜病缺血预处理中使用左西孟旦进行预处理对围术期病人预后无明显影响。     

左西孟旦治疗围手术期老年髋部骨折合并心衰患者的疗效研究

目的探讨左西孟旦治疗围手术期老年髋部骨折合并心力衰竭患者的疗效。 方法回顾性分析2013年1月至2016年12月于邯郸市第一医院接受手术治疗且符合纳入标准的老年髋部骨折合并心力衰竭的患者64例（股骨颈骨折30例,股骨转子间骨折34例）,根据围手术期是否使用左西孟旦,分为左西孟旦组和对照组,其中左西孟旦组32例,对照组32例,比较应用左西孟旦前、术后24 h、7 d后左室射血分数（LVEF）、心输出量（CO）、心脏指数（CI）、B型钠尿肽水平（BNP）,对左西孟旦的疗效进行评价。 结果左西孟旦组术后24 h、术后7 d LVEF、CI、CO均明显高于同时间对照组（LVEF：t=2.428,t=3.150;CI：t=3.349,t=3.777;CO：t=2.615,t=2.620,均P<0.05）,左西孟旦组术后24 h、术后7 d BNP水平明显低于对照组,差异有统计学意义（t=2.989,t=2.693,P<0.05）。 结论左西孟旦可改善老年髋部骨折合并心力衰竭患者围手术期的血流动力学指标,改善心脏功能及预后。     

七氟醚和异丙酚对冠状动脉旁路移植术患者心肌保护作用比较的Meta分析

目的 采用Meta分析法比较七氟醚和异丙酚对冠状动脉旁路移植术患者心肌的保护作用.方法 通过电子数据库检索比较冠状动脉旁路移植术患者七氟醚和异丙酚心肌保护作用的临床随机对照研究,文献检索至2008年9月.由两位作者分别对研究质量进行评估,并提取有关资料,主要包括患者术前情况、术中情况、体外循环后心脏指数、术后心肌肌钙蛋白Ⅰ水平、机械通气时间、正性肌力药物使用情况、ICU停留时间、住院时间、术后死亡、心肌梗死、心肌缺血和房颤的发生情况,采用RevMan 5.0软件进行Meta分析.结果 共纳入13项前瞻性临床随机对照研究,包括696例患者,其中七氟醚组402例,异丙酚组294例.两组患者术后机械通气时间、正性肌力药物使用率、术后病死率、心肌梗死和房颤的发生率差异无统计学意义(P>0.05).与异丙酚组相比,七氟醚组患者体外循环后心脏指数升高,术后心肌肌钙蛋白Ⅰ水平和心肌缺血发生率降低,ICU停留时间和住院时间缩短(P<0.05).结论 冠状动脉旁路移植术患者七氟醚的心肌保护作用优于异丙酚.     

Del Nido心肌保护液在成人心脏瓣膜手术中应用的病例对照研究

目的探讨Del Nido心肌保护液在成人心脏手术中心肌保护效果,分析其在成人心脏直视术中相关优势。方法回顾性分析2016年6月至2017年1月我院成人心脏瓣膜术中应用Del Nido心肌保护液96例患者的临床资料,其中男44例、女52例,平均年龄(51.36±13.31)岁,作为Del Nido心肌保护液组(DNC组)。选取同期应用传统心肌保护液96例患者作为传统心肌保护液组(CTC组),其中男53例、女43例,平均年龄(52.91±10.95)岁。记录主动脉阻断时间、体外循环时间、心肌保护液灌注次数及总量、自动复跳率、围术期输血量及术后24 h内正性肌力药使用情况等。结果 DNC组和CTC组患者年龄、体质量、射血分数、红细胞压积、体外循环时间、主动脉阻断时间差异无统计学意义(P0.05)。两组自动复跳率、术后24 h正性肌力药物评分、心肌酶学、肌钙蛋白-I及住ICU时间差异无统计学意义(P0.05)。与CTC组相比,DNC组术中心肌保护液灌注总量、灌注次数、围术期输血量均较少,差异具有统计学意义(P0.05)。两组术后均无新发心房颤动及院内死亡。结论 Del Nido心肌保护液在成人心脏瓣膜手术中有良好的心肌保护作用,同时可减少静态预充量,降低血液稀释及围术期输血量。     

左西孟旦对严重瓣膜病合并心房颤动患者行心脏手术影响的随机对照试验

目的比较左西孟旦与多巴胺用于合并心房颤动(房颤)的严重瓣膜疾病手术的疗效,探索左西孟旦用于心脏手术的有效性和安全性。方法将2014年2~6月泸州医学院附属医院48例患者用随机数字表法分为左西孟旦组[24例,男18例、女6例,年龄(52.3±16.2)岁)]和多巴胺组[24例,男15例、女9例,年龄(55.0±17.4)岁],比较两组患者的临床结果。结果左西孟旦组住院时间[(18.7±8.6)d vs(20.6±7.5)d,t=11.52,P=0.02]及急性肾损伤发生率[1/24 vs 5/24,χ2=25.30,P=0.01]短于或低于多巴胺组,其余临床早期结果差异无统计学意义。术后各时间点两组肌酸激酶同工酶(CK-MB)差异无统计学意义,但术后6~48 h两组心肌肌钙蛋白I(c Tn I)、脑钠肽(BNP)差异有统计学意义(P0.05)。术后5 d左西孟旦组左心室射血分数(LVEF)高于多巴胺组。结论左西孟旦用于严重瓣膜病合并房颤患者手术安全有效,且有一定的心肌保护和肾保护作用,其机理尚需进一步探讨。     

冠状动脉搭桥术中多巴胺与多巴酚丁胺对血液动力学的影响

多巴胺与多巴酚丁胺是心脏手术中常用的正性肌力药,本研究旨在评价二者同等剂量对冠状动脉搭桥手术病人脱离体外循环后血液动力学的影响。 资料和方法 随机选择冠状动脉搭桥手术病人24例,心功能NYHA分级Ⅰ～Ⅱ级,ASA分级Ⅱ～Ⅲ级,年龄42～74岁,其中男性17例,女性7例,随机分为2组(多巴胺组,多巴酚丁胺     

Use of levosimendan in patients with ischemic heart disease following mechanical reperfusion

Cardiac failure is among the most significant conditions associated with acute coronary syndrome. In ischemic heart disease, serious hemodynamic problems are reported in patients with left ventricular dysfunction during the acute phase despite mechanical revascularization. Several positive inotropic agents in addition to intra-aortic balloon pump (IABP) are required to support patients with impaired left ventricular pump function during this phase. Intravenous inotropic agents, beta-mimetics, and phosphodiesterase inhibitors lead to increases in the incidence of arrhythmia and myocardial O₂ consumption owing to their effect of increasing intracellular calcium amount, although they produce rapid hemodynamic improvements in cardiac failure. This causes severe problems particularly in cardiac failure of ischemic origin. Recently, levosimendan, a calcium-sensitizing agent with cardioprotective properties, is being used alone or in combination with IABP in cases with severe left ventricular systolic dysfunction during mechanical revascularization procedures (percutaneous coronary interventions, coronary bypass surgery). This review includes studies with levosimendan in cases not recovering due to myocardial stunning in the acute phase despite mechanical approaches applied.     

Predictors of inotropic support during weaning from cardiopulmonary bypass in coronary artery bypass grafting surgery

Early or prophylactic inotropic drug administration is occasionally required to facilitate separation from cardiopulmonary bypass (CPB) in cardiac surgery. However, it is not without untoward effects and should be conducted on the basis of rational criteria. The purpose of our study was to clarify variables associated with the requirement for inotropic support during separation from CPB and to testify whether pre-CPB left ventricular (LV) function, as evaluated by transesophageal echocardiography (TEE), is one of the significant variables. Clinical profile data and TEE findings were retrospectively analyzed for 91 patients who had received elective primary isolated coronary artery bypass grafting (CABG) surgery. Post-CPB inotropic drug administration initiated prior to aortic decannulation was considered inotropic support for terminating CPB. Stepwise multiple logistic regression analysis identified pre-CPB LV regional wall motion abnormalities (RWMA), NYHA class, age, and duration of CPB (in order of significance) as factors associated with inotropic support for discontinuing CPB. Pre-CPB LV enddiastolic area or fractional area change was not a significant variable in the multivariate model. Our result suggests that evaluation of pre-CPB LV RWMA is useful in predicting the need of inotropic intervention during separation from CPB in patients undergoing CABG surgery. This study was performed at The Weiler Hospital of The Albert Einstein College of Medicine, and was presented in part at the 17th annual meeting of The Society of Cardiovascular Anesthesiologists, Philadelphia, Pennsylvania, May 8–10, 1995     

Xenon does not impair the responsiveness of cardiac muscle bundles to positive inotropic and chronotropic stimulation

BACKGROUND: Most volatile anesthetics exhibit a direct myocardial depressant effect. This side effect often limits their applicability in patients with impaired cardiac function. Xenon is a new gaseous anesthetic that did not show any adverse cardiovascular effects in clinical and experimental studies. The authors tested the hypothesis that xenon does not affect myocardial contractility or the positive inotropic effect of isoproterenol, calcium, and increase in pacing rate in isolated guinea pig ventricular muscle bundles. METHODS: Thin ventricular muscle bundles from guinea pig hearts with a mean diameter of 0.4-0.45 mm were prepared under stereomicroscopic control. Force of contraction and contraction times were studied in muscles superfused with medium equilibrated with either 65% xenon and 35% oxygen (xenon group), 1.2% isoflurane in oxygen (isoflurane group), or 65% nitrogen and 35% oxygen (control group). In addition, the positive inotropic effects of calcium, isoproterenol (10(-10)-3 x 10(-8) M) and increasing frequency (0.5-2 Hz) were studied during xenon and isoflurane exposure. RESULTS: In contrast to isoflurane, xenon did not alter myocardial force of contraction or contraction times. The positive inotropic effect of isoproterenol, calcium, and increasing pacing frequencies did not differ between the muscles exposed to xenon and the control group. Isoflurane elicited the expected negative inotropic effect (30% reduction of force of contraction) but did not impair the response to inotropic stimuli. CONCLUSIONS: Xenon does not alter myocardial contractility and the response to inotropic stimuli such as calcium, isoproterenol, or increase in pacing frequency in isolated guinea pig ventricular muscle bundles.     

Xenon Does Not Impair the Responsiveness of Cardiac Muscle Bundles to Positive Inotropic and Chronotropic Stimulation

Background: Most volatile anesthetics exhibit a direct myocardial depressant effect. This side effect often limits their applicability in patients with impaired cardiac function. Xenon is a new gaseous anesthetic that did not show any adverse cardiovascular effects in clinical and experimental studies. The authors tested the hypothesis that xenon does not affect myocardial contractility or the positive inotropic effect of isoproterenol, calcium, and increase in pacing rate in isolated guinea pig ventricular muscle bundles.

Methods: Thin ventricular muscle bundles from guinea pig hearts with a mean diameter of 0.4-0.45 mm were prepared under stereomicroscopic control. Force of contraction and contraction times were studied in muscles superfused with medium equilibrated with either 65% xenon and 35% oxygen (xenon group), 1.2% isoflurane in oxygen (isoflurane group), or 65% nitrogen and 35% oxygen (control group). In addition, the positive inotropic effects of calcium, isoproterenol (10-10 - 3 x 10-8 m) and increasing frequency (0.5-2 Hz) were studied during xenon and isoflurane exposure.

Results: In contrast to isoflurane, xenon did not alter myocardial force of contraction or contraction times. The positive inotropic effect of isoproterenol, calcium, and increasing pacing frequencies did not differ between the muscles exposed to xenon and the control group. Isoflurane elicited the expected negative inotropic effect (30% reduction of force of contraction) but did not impair the response to inotropic stimuli.     

Levosimendan in cardiac surgery: current best available evidence

Recent upsurge in referral of patients with high perioperative risk or compromised left ventricular function for cardiac surgery has lead to an increasing use of pharmacologic support in the form of vasodilator and inotropic therapy to achieve improvement of tissue perfusion in the perioperative period or to support weaning from cardiopulmonary bypass. Traditionally, perioperatively used inotropic agents, epinephrine, dobutamine, and milrinone, are limited by significant increases in myocardial oxygen consumption, proarrhythmia, or neurohormonal activation. Levosimendan, a new inodilator for the treatment of decompensated heart failure, has also shown promise in elective therapy of cardiac surgical patients with high perioperative risk or compromised left ventricular function, as well as in rescue therapy of patients with difficult weaning from cardiopulmonary bypass. This review article briefly discusses the pharmacology of levosimendan and evaluates current best available evidence to assess the safety and efficacy of levosimendan usage in cardiac surgery.     

Timely use of a CentriMag heart assist device improves survival in postcardiotomy cardiogenic shock

Abstract Background: Postcardiotomy cardiogenic shock (PCS) is often fatal despite inotropic and circulatory support. We compared our experience with the CentriMag left ventricular assist device (LVAD) for patients with PCS at two time periods: in the operating room (OR) after unsuccessful weaning from cardiopulmonary bypass (CPB) and after transfer to the intensive care unit (ICU). Methods: We reviewed 22 patients’ records (13 men, nine women; age, 65 ± 12 years) who underwent open heart surgery (January 2004 to September 2009) and required LVAD support for PCS despite maximal inotropic and intra‐aortic balloon pump (IABP) support. In ten patients who could not be weaned from CPB despite high‐dose inotropic therapy (≥ 3 agents) and IABP support, the CentriMag was implanted in the OR (immediate group). The other 12 patients were weaned from CPB with high‐dose inotropic therapy and IABP but became increasingly unstable or had a cardiac arrest in the ICU, and the CentriMag was implanted for circulatory support (delayed group). Results: Preoperatively, the average ejection fraction was 40%± 12%, the creatinine level was 1.6 ± 0.6 mg/dL, and the European Systematic Coronary Risk Evaluation was 13.1 ± 4.6. The duration of CentriMag support was 5 ± 3 days. The immediate group had significantly better survival (7/10 vs. 2/12, p = 0.027), higher cardiac index (2.4 ± 0.3 L/min/m² vs. 1.7 ± 0.3 L/min/m², p = 0.001), and lower pulmonary capillary wedge pressure (20 ± 6 mmHg vs. 29 ± 8 mmHg, p = 0.024) than the ICU group. No perioperative complications related to device implantation occurred. Conclusion: In patients with PCS, timely placement of a CentriMag LVAD may increase the chance of eventual recovery. (J Card Surg 2011;26:548‐552)     

Amrinone in perioperative low cardiac output syndrome

Amrinone has been shown to have a beneficial effect on left ventricular function in low output syndrome (LOS), but its use after open-heart surgery has not been extensively revised. We studied 10 patients with LOS post-cardiopulmonary bypass (CPB), who failed to respond to conventional treatment (vasoactive drugs plus intraaortic balloon pump) and were treated with amrinone, 0.75 mg.kg-1 followed by a continuous infusion of 5 to 10 micrograms.kg-1-min-1. One patient failed to respond to the treatment and subsequently died, but in the other nine patients blood pressure and cardiac index increased, left filling pressure decreased and they were successfully weaned from the CBP and survived. These results suggest that amrinone, either alone or combined with other inotropic drugs and mechanical support, is a valuable drug in the management of LOS after CPB.     

Successful use of levosimendan in a patient during cardiopulmonary bypass

Levosimendan (LS) is a novel calcium sensitizer drug that enhances cardiac contractility without increasing myocardial oxygen consumption, and induces vasodilatation. Positive inotropic support is routinely used for weaning from cardiopulmonary bypass circulation in patients with reduced left ventricular function. This case report represents the successful usage of LS for weaning from cardiopulmonary bypass circulation after coronary artery bypass surgery. Levosimendan infusion was started at the sixth hour of cardiopulmonary bypass circulation. There was a dramatic increase in cardiac output 20 minutes after LS infusion, and weaning from cardiopulmonary bypass circulation was achieved. We suggest that LS enhances cardiac performance during and after cardiopulmonary bypass, and can be useful for patients who are unable to be weaned from cardiopulmonary bypass.     

Off-pump insertion of continuous flow left ventricular assist devices

BACKGROUND AND AIM OF THE STUDY: Traditional left ventricular assist device (LVAD) implantation requires extensive dissection and use of cardiopulmonary bypass (CPB). Potential adverse effects of CPB in very ill end-stage heart failure patients include right ventricular dysfunction, end-organ injury, and bleeding. We sought to evaluate the feasibility and outcome of LVAD insertion without CPB. METHODS: The Jarvik 2000 is an axial-flow pump newly involved in a phase I clinical trial in status I patients as a bridge to transplantation. Seven patients received this pump through thoracotomy or sternotomy with or without the use of CPB. RESULTS: All patients had NYHA class IV heart failure with end-organ dysfunction requiring inotropic therapy. Two were in cardiogenic shock, necessitating full CPB support. Five patients had the Jarvik implanted off-CPB. The off-CPB patients were associated with decreased length of surgery, mechanical ventilation, blood transfusions, inotropic support, and hospital stay including rehabilitation. Nearly all of the patients had complete resolution of liver and kidney dysfunction. CONCLUSION: We have demonstrated that off-CPB insertion of axial flow LVADs is feasible, safe, and potentially advantageous. Although we are encouraged by the perioperative simplicity of this strategy, we acknowledge that additional implants and comparisons of outcomes with traditional pulsatile and continuous flow device techniques will be necessary to advocate its widespread adoption.     

Amrinone,in combination with norepinephrine,is an effective first-line drug for difficult separation from cardiopulmonary bypass

A crucial element for weaning patients from cardiopulmonary bypass (CPB) rests on the selection of an appropriate therapeutic regimen. Amrinone, a phosphodiesterase III inhibitor, combines inotropic support with pulmonary and systemic vasodilatation, without increasing heart rate (HR) or myocardial oxygen consumption. These characteristics should be useful in the failing heart during weaning from CPB. Nineteen patients were included in this prospective, open-labelled, phase IV study when systolic blood pressure (SBP) <80 mmHg, and diastolic pulmonary artery pressure (DPAP) > 15 mmHg or central venous pressure (CVP) > 75 mmHg, during progressive separation from CPB. At that moment, CPB flow was increased to alleviate heart failure and amrinone administered as a bolus (0.75 mg · kg^?1) followed by an infusion (10 μg · kg^?1 · min^?1). Weaning from CPB was then resumed and haemodynamic variables (SBP, DPAP, CVP and HR) were compared with those measured at CPB flow when failure had first occurred. Failure to wean from CPB occurred at 57 ± 25% of full pump flow. After the amrinone bolus, DPAP and CVP decreased by 20% and 21% respectively. Subsequently, 16 patients required the infusion of norepinephrine (4-8 fig-min^?1) to maintain a SBP > 80 mmHg. Heart rate remained unchanged after the bolus of amrinone, after separation from CPB, and no arrhythmias were noted. Successful weaning from CPB was possible 12 ± 8 min after the amrinone bolus. Weaning resulted in a cardiac index similar to that measured pre-bypass. Amrinone is rapidly effective during weaning from CPB and, in combination with norepinephrine, provides the necessary inotropic support during this unstable period.