左心辅助对右心功能影响的实验研究

目的　比较左心辅助对正常及急性缺血性功能不全右心室血流动力学的影响 ,初步探讨左心辅助后右心衰的发生原因。方法　以左心房 -主动脉旁路方式植入左心辅助装置于健康成年犬心脏 ,以 70 %辅助流率行左心辅助 ,在辅助前后记录中心静脉压 (CVP)、心输出量 (CO)、平均动脉压 (MAP)、肺动脉压 (PAP)、右心室最大收缩压(RVSPmax)、右心室最大收缩压一阶导数 (RVdp/dtmax)。停左心辅助并结扎右冠状动脉 ,5min后再行左心辅助 ,分别在辅助前后记录上述指标。结果　在右心功能正常时 ,左心辅助后肺动脉压下降 17% (P <0 0 1) ,其他血流动力学指标无明显变化 ;在右心功能不全时行左心辅助后 ,CVP上升 2 % (P>0 0 5 ) ,CO下降 4 % (P <0 0 5 ) ,MAP下降 7% (P <0 0 5 ) ,PAP下降 33% (P <0 0 1) ,RVSPmax及RVdp/dtmax分别下降18%和 14 % (P <0 0 1)。结论　在正常及急性缺血性功能不全右心室行左心辅助后血流动力学的不同变化趋势表明 ,原已存在功能损害的右心室能否承受LVAD应用后所产生的血流动力学的变化是左心辅助应用后发生右心衰的主要原因     

卡维地洛对缺血性心肌病患者心功能及血浆脑钠素的影响

缺血性心肌病 (ICM)是指冠状动脉病变引起心肌缺血、坏死 ,心肌局限性或弥漫性纤维化或硬化 ,导致心脏扩大和心力衰竭的一种临床综合征 ,常因反复心衰和心律失常而猝死。大规模临床研究显示 ,第三代β受体阻滞剂卡维地洛能改善心衰患者的预后。但是卡维地洛治疗缺血性心肌病的疗效少见报道。2 0 0 2年 3月～ 2 0 0 2年 9月 ,我们用卡维地洛治疗缺血性心肌病 1 3例 ,并与常规治疗患者进行比较 ,观察治疗前后患者心功能及血浆脑钠素 (BNP)的变化 ,报告如下。1　资料与方法1 .1　病例选择　选自同期住院的缺血性心肌病患者 2 6例 ,均符合 W…     

左心辅助装置与右心衰

左心辅助装置 (L VAD)在临床中的成功应用 ,正受到越来越多人的肯定和接受 ,在术后严重低心排的病人 ,其抢救存活率可达 5 0 % [1] ,而在终末期心泵功能衰竭等待心脏移植的病人和急性心肌炎所致的心源性休克病人其存活率更高。但一个不容忽视的问题是在应用左心辅助的病人中 ,右心衰的发生率约占 2 0 %～ 30 % [2 ,3] ,是造成病人死亡的最重要原因之一。右心衰发生的原因和机制目前还没有完全清楚 ,在如何处理上也存在一定的争论。现多数学者认为 ,左心辅助后右心衰的发生原因和机制包括 [4] :右心室原已存在的病变引起右心功能损害 ;右心…     

血浆脑钠素浓度与心功能不全患者心脏收缩功能的关系

目的探讨脑钠素(BNP)浓度与心功能不全严重程度及左室收缩功能的关系。方法用放射免疫分析法测定了43例心功能不全患者(观察组)的BNP浓度，采用超声心动图测量并计算其左室射血分数(LVEF)、舒张末期内径(LVED)、左房内径(LAID)并与18例健康人(对照组)比较。结果观察组BNP浓度显著高于对照组；BNP浓度与NYHA分级呈正相关，BNP浓度与左室收缩功能不全程度具有良好的相关性。结论BNP浓度可以反映心力衰竭的严重程度及左室收缩功能不全的程度。     

血浆脑钠素检测在急性心肌梗死患者的临床应用

目的　探讨急性心肌梗死患者过程中血浆脑钠素浓度的变化。方法　用放射免疫法测定 2 4例急性心肌梗死患者入院即刻、入院后第 1、7、14天及正常对照组的血浆BNP浓度。上述患者入院后第 1、7、14天 ,取心尖标准四腔切面 ,根据改良的Simpson法 ,测量并计算左室射血分数 ,取 2个心动周期的均值。结果　 2 4例患者血浆BNP浓度在所测各时间点均高于正常对照组 (12 7± 2 2 )ng/L ,血浆BNP浓度与时间对应的左室射血分数之间存在较密切的负相关 (r=0 6 9,P <0 0 1)。结论　急性心肌梗死患者血浆BNP浓度显著升高 ,并在入院后 2 4h出现高峰 ,心肌急性缺血性损伤和收缩功能的降低可能是引起血浆BNP浓度升高的原因之一     

血浆脑钠素水平评价左心室收缩功能不全的意义

目的探讨我国正常人群、左心收缩功能不全及和肺源性呼吸困难患者脑钠素(BNP)的血浆浓度,及其与心功能分级的关系.为BNP在心力衰竭(心衰)诊断和呼吸困难鉴别诊断提供理论依据.方法使用BIOSITE公司的TriageBNP干氏快速诊断方法对81例心衰患者、40例正常者和40例肺源性呼吸困难患者的BNP水平进行测量,比较三者间浓度差别;使用射血分数≤45%作为心功能不全诊断的金标准, 绘制ROC曲线,得出BNP诊断的最佳阈值.结果①心衰组与正常对照组及肺源性呼吸困难组的BNP水平差异有统计学意义(P<0.01),正常对照组与肺源性呼吸困难组的BNP水平差异无统计学意义(P>0.05); ②心衰组不同NYHA分级的BNP水平比较差异均有统计学意义(均P<0.01);③ ROC曲线下面积为0.991,选择97.75 ng/L为BNP诊断的最佳阈值,其诊断心衰的敏感性为93.8%,特异性为96.1%.结论BNP对左心收缩功能不全有很高的灵敏度和特异度,可用于呼吸困难的鉴别诊断.     

血浆脑钠素评价无症状性心衰的临床意义

目的 评价血浆脑钠素(BNP)对无症状性心衰(NSF)的诊断价值。方法 用HP5000彩色多普勒超声动态心动图(UCG)测定左室射血分数(LVEF)和按心功能(NYHA)分级,将病例分为无症状性心衰组(A组)21例和心衰组(B组)28例,选取心功能正常的健康者14例为对照组(C组)。采用放射性免疫法测定3组血浆BNP浓度。结果 A组血浆BNP浓度(97.82±49.06)ng/L与C组(39.08±18.60)ng/L比较有显著性差异(P<0.001)。血浆BNP>75.00ng/L(C组的x+1.96s)时,诊断NSF,敏感性为91％,特异性为95％。结论 NSF者血浆BNP浓度明显增高,BNP可作为诊断NSF的1项比较理想的指标,具有普及推广应用的前景。     

急性脑梗死患者血浆脑钠素水平变化及临床意义

脑钠素（BNP）是一种神经激素，具有与心钠素（ANP）相似的结构和功能，对心血管的自我调节和血容量具有重要作用，其促尿钠排泄效应可引起血清钠离子水平降低，血液浓缩而导致血容量减少。慢性心功能不全、急性心肌梗死、原发性高血压和心律不齐，如心房颤动（房颤）的患者中均发现BNP水平升高。我们检测急性脑梗死患者的BNP浓度变化，旨在探讨其在急性脑缺血期血液动力学方面的可能作用。     

不同病因心衰患者血浆脑钠素水平的影响

目的　观察不同病因心衰患者血浆脑钠素(BNP)水平的变化 ,探讨BNP在心衰发病机制中所起的作用以及 β -受体阻滞剂对心衰患者BNP水平的影响。 方法　采用酶联免疫吸附试验 (ELISA)法测定心衰患者血浆BNP水平。结果　心衰组BNP水平与正常对照组相比显著升高(P <0 0 1)。重度心衰心功能Ⅲ、Ⅳ级BNP水平明显高于心功能Ⅱ级。BNP变化的幅度在冠心病、扩张型心肌病不同病因心衰中有所不同 ,冠心病心衰BNP水平升高更明显 (P <0 0 1)。心衰患者中常规治疗组与非 β -受体阻滞剂治疗组相比 ,美托洛尔和卡维地洛治疗组BNP水平明显降低 (P <0 0 5 )。结论　心衰患者血浆BNP水平显著升高 ,BNP水平与心衰严重程度呈正相关 ,冠心病心衰BNP水平较扩张型心肌病组明显升高 ,提示冠心病心肌缺血损伤可能进一步促进BNP分泌。美托洛尔和卡维地洛均能下调心衰BNP水平 ,可能是不同β -受体阻滞剂逆转心衰神经激素过度激活的共同作用机制之一。     

不同时间点动态监测心电图及脑钠素对老年急性左心衰患者的预后评价

目的探讨心电图监测结合脑钠素(BNP)对急性左心衰(ALHF)老年患者预后的应用价值。方法对128例ALHF急性发作后6 h内及24、72 h血浆BNP进行检测,并行常规心电图检查。根据患者出院时的状态分为预后理想组(60例)、预后不佳组(45例)及死亡组(23例)。结果预后理想组急性发作后24、72 h血浆BNP、QRS波时限以及QTc间期的下降均较预后不佳组及死亡组明显(均P<0.05),而死亡组QRS波时限、QTc间期呈延长趋势。多因素Logistic回归分析结果显示BNP和QRS波、QTc间期是影响患者预后的独立危险因素。结论连续多个时点动态监测血浆BNP和心电图的变化特征,对评价老年ALHF患者的预后及死亡具有重要意义。     

Effects of milrinone for right ventricular failure after left ventricular assist device implantation

Right ventricular failure after left ventricular assist device implantation sometimes requires additional mechanical right ventricular support. The effectiveness of nitrates, prostaglandin, or nitric oxide inhalation in such cases has already been reported. However, there are few reports on the administration of phosphodiesterase inhibitor for right ventricular failure after left ventricular assist device implantation. We report two patients with right ventricular failure after left ventricular assist device implantation successfully treated with milrinone. Both had residual pulmonary hypertension due to high pulmonary vascular resistance after left ventricular assist device implantation. However, intravenous milrinone caused a significant reduction in pulmonary vascular resistance and an increase in left ventricular assist device flow. Milrinone acts as both an inotropic agent and a direct vasodilator, and thus may avoid the need for mechanical support for right ventricular failure due to residual pulmonary hypertension after left ventricular assist device implantation. Received: May 28, 2001 / Accepted: September 22, 2001     

Left ventricular assist device driveline infections

This article reviews some important aspects of driveline infection in patients under left ventricular assist device (LVAD) support, including epidemiology, causes, diagnosis, and treatment options, both medical and surgical. Focus is placed on prevention along every aspect of the process of LVAD therapy, as the authors believe this is the most efficient measure to fight driveline infections. Once driveline infection is present, early recognition and adequate treatment, including surgical measures, play a central role management, and are key to achieving the goals of LVAD support.     

Evolvement of left ventricular assist device: the implications on heart failure management

Heart failure (HF) is a potentially fatal disease that affects increasing number of people worldwide. Although heart transplant is the “gold standard” therapy for HF, due to the limited availability of organs, many patients died when waiting for the transplant. Left ventricular assist device (LVAD), as a mechanical circulatory support, has become a new light for patients with HF. With the technical advancements, LVADs work not only as a bridge to transplant, but also assist heart recovery and even as a destination therapy in long-term treatment. This observation paper reviewed the development of LVAD and its clinical roles. The challenges and possible solutions in nursing care for patients with LVAD at different stage of implantation were discussed. The healthcare professionals could obtain a better understanding about the LVAD treatment for HF patients.     

Effects of left ventricular assist device on pulmonary functions and pulmonary hemodynamics: A meta-analysis

BACKGROUNDGiven current evidence, the effect of left ventricular assist device (LVAD) implantation on pulmonary function tests remains controversial.AIMTo better understand the factors contributing to the changes seen on pulmonary function testing and the correlation with pulmonary hemodynamics after LVAD implantation.METHODSElectronic databases were queried to identify relevant articles. The summary effect size was estimated as a difference of overall means and standard deviation on a random-effects model.RESULTSA total of four studies comprising 219 patients were included. The overall mean forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and diffusion lung capacity of carbon monoxide (DLCO) after LVAD implantation were significantly lower by 0.23 L (95%CI: 0.11-0.34, P = 00002), 0.18 L (95%CI: 0.03-0.34, P = 0.02), and 3.16 mmol/min (95%CI: 2.17-4.14, P < 0.00001), respectively. The net post-LVAD mean value of the cardiac index was significantly higher by 0.49 L/min/m² (95%CI: 0.31-0.66, P < 0.00001) compared to pre-LVAD value. The pulmonary capillary wedge pressure and pulmonary vascular resistance were significantly reduced after LVAD implantation by 8.56 mmHg (95%CI: 3.78-13.35, P = 0.0004), and 0.83 Woods U (95%CI: 0.11-1.55, P = 0.02), respectively. There was no significant difference observed in the right atrial pressure after LVAD implantation (0.61 mmHg, 95%CI: -2.00 to 3.32, P = 0.65). Overall findings appear to be driven by studies using HeartMateII devices.CONCLUSIONLVAD implantation might be associated with a significant reduction of the spirometric measures, including FEV1, FVC, and DLCO, and an overall improvement of pulmonary hemodynamics.     

Minimally invasive is the future of left ventricular assist device implantation

There have been many factors that have allowed for progressive improvement in outcomes and lower complication rates. These include the improvement in left ventricular assist device (LVAD) technologies, combined with better understanding of patient management, all these. Nowadays the numbers of LVAD implantations exceed the number of annual heart transplants worldwide. Minimally invasive procedures are shown to improve the surgical outcome in both LVAD insertion and replacement. These minimally invasive techniques can be grouped grossly into shifting from on-pump to off-pump implantation, alternative access for implantation other than sternotomy, and a combination of both, which should be the ultimate aim of minimally invasive LVAD implantation. Here we describe the alternative techniques and configurations of minimally invasive and sites of implantation.     

左心室辅助装置逆转心衰病理改变的分子机制研究进展

随着生活水平的提高和寿命的延长,心力衰竭在中国的发病率成逐年上升趋势。目前临床上心衰诊断一经确定,5年内的死亡率超过60％,终末期心衰患者预后更差,即使经过药物治疗,1年内的死亡率仍达75％。随着疾病进展,心脏对药物治疗的反应不断减弱,因此疾病后期,供临床医生选择的有效治疗手段十分有限,患者的生存率和生活质量受到很大影响。     

Subacute gastric perforation caused by a left ventricular assist device

This case report describes a rare complication of a left ventricular assist device (LVAD). A patient with ischemic cardiomyopathy had an LVAD placed due to intractable congestive heart failure following a large anterior myocardial infarction. The patient developed chronic bacteremia and multiple septic episodes. A gastric endoscopy revealed perforation of the anterior wall of the stomach by the LVAD. Gastric acid related erosions were present on the metallic surface suggesting prolonged exposure. This is the second case report of this rare complication and the first case report of a subacute course.     

Minimally invasive implantation of left ventricular assist device HeartWare HVAD

IntroductionLong-term left ventricular assist devices are nowadays part of standard therapy for patients in terminal phase of heart failure. Lower invasiveness of implantation might have the potential to enhance results of these high risk patients. The aim of this study is to introduce our minimally invasive approach to the implantation of left ventricular assist device of the latest generation HeartWare ventricle assist device (HVAD) and our initial experience with this method.MethodsIn our department we implanted HVAD between November 2013 and November 2014 in 8 patients as a bridge to heart transplantation. All patients were male with average age 59.5 ± 6.4 years. Basic diseases were dilated cardiomyopathy in 6 patients (75%), ischemic cardiomyopathy in 2 patients (25%). The mean value of left ventricular ejection fraction was 10 ± 3.6%, right ventricular ejection fraction was 35 ± 5.6%. Access to the left ventricular apex was reached by left-sided thoracotomy of approximately 8 cm. To access the ascending aorta we used upper J ministernotomy.ResultsMinimally invasive implantation was successfully done in all patients. In one patient closure of foramen ovale was simultaneously performed. Most patients (75%) were extubated on the first postoperative day. In one case, a failure of the right ventricle occurred with the need for temporary right-sided circulatory support device Centrimag. No patient died, four patients have successfully undergone heart transplantation, other are followed on an outpatient basis.ConclusionMinimally invasive implantation of left ventricular assist device HeartWare HVAD is safely feasible. After a very good initial experience with this technique it has become the method of choice in our department.     

Pre-implant left ventricular dimension is not associated with worse outcomes after left ventricular assist device implantation

BackgroundLeft ventricular dimension has the potential to impact clinical outcomes following implantation of left ventricular assist devices (LVAD). We investigated the effect of pre-implant left ventricular end-diastolic diameter (LVEDD) on outcomes following LVAD implantation.MethodsPatients implanted with a continuous-flow LVAD between 2004 and 2018 at a single institution were included. The primary outcome was death while on LVAD support. Secondary outcomes included adverse event rates such as renal failure requiring dialysis, device thrombosis, and right ventricular failure. The LVEDD measurements were dichotomized using restricted cubic splines and threshold regression. Survival was determined using Kaplan-Meier estimates. Multivariable logistic regression was used to determine risk-adjusted mortality based on LVEDD.ResultsA total of 344 patients underwent implantation of a continuous flow LVAD during the study period. The optimal cut point for LVEDD was 65 mm, with 126 (36.6%) subjects in the <65 mm group and 165 (48.0%) in the >65 mm group. The LVEDD <65 mm group was older, had more females, higher incidence of diabetes, more pre-implant mechanical ventilation, and more admissions for acute myocardial infarctions (all, P<0.05). Importantly, post-implant adverse events were similar between the groups (all, P>0.05). Risk-adjusted survival at 1-year (OR 1.3, 95% CI: 0.6–2.5, P=0.53) was also comparable between the groups. Furthermore, incremental increases in LVEDD when modeled as a continuous variable did not impact overall mortality (OR 0.98, 95% CI: 0.9–1.0, P=0.09).ConclusionsPreoperative LVEDD was not associated with rates of major morbidities or mortality following LVAD implantation.