模拟野战条件，自主研制介入方舱内临时起搏实验

目的:研究模拟野战条件下在自主创新研制介入方舱内行临时起搏实验的可行性和时效性。方法:对5例正常狗在微创介入方舱内使用普通电极导管进行急诊心脏临时起搏模拟操作,观察该过程的时间,和操作效果,以及舱内人员的配合。结果:应用普通电极导管急诊心脏超速起搏5例全部成功,股静脉穿刺,无穿刺部位血肿、感染,血栓栓塞,心脏穿孔等并发症发生。时间在10分钟以内。结论:依托微创介入方舱,在野外恶劣条件下进行临时起搏的急救过程安全,实用,快捷。可用于战时以及非战争卫勤急救任务中,发挥重要作用。     

临时起搏器经皮冠状动脉介入术治疗高风险冠状动脉病变的效果观察

目的分析并总结采用临时起搏器在实施经皮冠状动脉介入术治疗高风险冠状动脉病变中的应用效果。方法回顾性分析在临时起搏器支持下实施PCI的18例高危病人的临床资料,分析临时起搏器置入以及冠脉介入的操作情况。结果本组病人置入临时起搏电极起搏成功率达到100％。结论联合应用临时起搏器与经皮冠脉介入术治疗急性心肌梗死（AMI）与慢性血管闭塞性病变患者,能够降低经皮冠脉介入术治疗中由于严重心律失常导致的血液动力学改变,使病人尽快恢复正常心率以及各主要脏器的供血,减少患者的病死率,具有较高的安全性,值得在临床上广泛推广应用。     

野战微创介入方舱内实施对脾脏损伤的快速救治实验

目的:探讨在战争或自然灾害等野战特定条件下,使用野战微创介入方舱,现场对脾脏创伤实施快速微创介入栓塞救治的可行性及效果,形成介入方舱内对脾脏进行快速介入栓塞救治的流程。方法:野战条件下,展开野战介入方舱,在血管造影机下对大动物(狗)脾动脉进行血管内穿刺造模,建立脾动脉损伤模型,按照方舱内快速微创介入救治的流程,对脾动脉受损伤的动物(狗)实施腹部内受损脾动脉的栓塞止血术式。结果:按照设定的预案,对脾损伤的模型动物实施早期介入栓塞脾动脉止血治疗,全部实验动物2周存活率为100%。结论:野战条件下,考虑到转运风险时或者伤情十分紧急时,靠近事发现场展开野战微创介入方舱,对腹部脾脏损伤开展紧急介入栓塞止血救治,不仅可为病人后续的治疗争取宝贵时间,大幅降低一线伤死率,而且脾脏的保全也提高伤员愈后的生活质量。     

综合手术救治方舱内采用不同栓塞材料救治脾破裂的对比研究

目的：探讨在战争或自然灾害等野战条件下,使用综合手术介入方舱,现场对脾脏实施快速微创介入栓塞的可行性及效果,对比分析综合手术救治方舱内采用不同栓塞材料介入救治脾破裂的适应症及有效性、安全性。方法：采用Seldinger技术,经股动脉插管至脾动脉,行数字减影血管造影术（DSA）,显示出血动脉,然后超选择插管至该动脉,经导管注入不同类型栓塞剂以栓塞出血动脉。术后观察不同栓塞剂成功封堵受损血管所用时间,封堵时造影剂用量,封堵效果。结果：手术均成功,止血效果确切,无严重并发症。术后观察2周动物无死亡。结论：综合手术救治方舱具有良好的机动性和较强的自然环境适应能力,灾难现场应用综合手术救治方舱开展血管损伤应急介入救治具有可行性。根据血管损伤的不同类型,恰当选择不同类型的栓塞剂,可以取得很好的疗效。     

气囊漂浮电极导管临时右心室起搏处理心跳骤停

对因缓慢心律失常和心搏停止实施紧急起搏治疗尚无统一方法。作者采用腹股沟处右股静脉穿刺,置入气囊漂浮电极导管临时右心室起搏,治疗不同原理引起的高度房室传导阻滞,窦房结功能不良导致心跳骤停而出现阿－斯综合症的病人,结果显示起搏良好,有效循环恢复。     

急性下壁心肌梗死急诊PCI术中应用临时起搏器与阿托品的对比研究

目的：探讨临时起搏器与阿托品在急性下壁心肌梗死急诊经皮冠状动脉介入治疗（PCI）中应用的疗效。方法：入选2012 年2 月至2013 年8 月我院收治的发病12 小时内,诊断为急性下壁心肌梗死并接受急诊PCI治疗的患者92 例,依据治疗方法的不同 将病例分为临时起搏组和阿托品组,并对病例进行为期一年的追踪随访,收集患者平均住院天数、平均住院费用、再灌注心律失 常、心肌梗死后心绞痛、心肌梗死后心衰发生率资料。结果：临时起搏组的平均住院天数、平均住院费用、心肌梗死后心绞痛、心肌 梗死后心衰发生率均显著低于阿托品治疗组（P 均<0.05）,阿托品治疗组的再灌注心律失常发生率则明显低于临时起搏组（P<0. 05）。结论：急性下壁心肌梗死急诊PCI中应用临时起搏器,具有治疗成本低,降低心血管事件发生率的优点,而阿托品治疗在改 善再灌注心律失常的疗效上则显著优于临时起搏治疗。     

自制起搏电极在心脏电生理实验中的应用研究

本文探索了自制起搏电极在心脏电生理研究中的应用,通过选择适当的材料,分为三部分制作电极：极片部分、起搏器接口部分、焊封与绝缘。最后,将电极缝合于犬的心脏进行起搏。结论是自制起搏电极应用于动物实验进行心脏电生理的研究是可行的。     

经颈静脉途径制备Beagle犬心脏记忆模型

目的经颈静脉途径应用心室起搏的方法制备心脏记忆犬模型。方法 8只普通级成年健康Beagle犬经腹腔麻醉后,Seldinger’s法穿刺颈外静脉成功后送入心内膜起搏电极,将电极头端固定于右室心尖部,近端连接于脉冲发生器。起搏频率设置较犬窦性心律时的基础心率快15%,保证起搏器连续起搏。结果连续起搏1周后所有动物均成功制备为心脏记忆模型。建模后犬的心率、呼吸、体重与建模前比较,无明显改变;所有模型组犬起搏前心电图均为窦性心律,起搏1周后出现心脏T波记忆,在下壁导联以及胸前导联均出现T波倒置,停止起搏后,心脏T波记忆逐渐消失;模型组犬与正常组犬心肌病理相比,无明显改变。结论经颈静脉途径应用心室起搏法建立心脏记忆犬模型的方法,具有手术简单,创伤小,诱发方式与临床相似等优点,为深入展开心脏记忆的机制研究奠定基础。     

颈外静脉穿刺术在急诊急救中的应用

目的探讨颈外静脉穿刺术在急诊急救工作中的临床应用效果。方法对30例急诊急危重患者在抢救中选择应用留置针颈外静脉穿刺术,并观察穿刺成功率和抢救效果。结果 30例患者均能及时建立静脉通路,及时采血及输液,保证了抢救用药及静脉通道畅通,抢救效果显著。结论颈外静脉穿刺术既提高了抢救成功率,又减轻了病人的痛苦,而且操作安全便捷,可以广泛应用于急诊急救中。     

非侵入性经皮体外起搏动物实验及临床应用报告

非侵入性经皮体外起搏(NoninvasivePercutaneous Temporary Cardiac Pac-ing)简称NTP,是最快速、有效、安全、简便的紧急心脏起搏方法,我院于1988年6月至今使用上海医电厂康殿邦总工程师设计研制的XGQ—Ⅰ型心脏急救起搏器及叶铭工程师设计研制的国内首创的LE—1浮悬式薄膜型经皮起搏电极进行多次动物实验及临床应用,证明性能可靠,操作方便,安全有效。动物实验方法及结果:精选健康狗3只,体重17—23公斤,常规麻醉后经股A、股V分别插入左右心导管以监测主A、肺A     

N-乙酰半胱氨酸对犬心房快速起搏电重构的影响

目的：探讨N-乙酰半胱氨酸（NAC）对犬心房快速起搏电重构的影响。方法：取16只犬,随机分为对照组和NAC干预组。NAC组按照15mg／kg／d剂量给予NAC口服6周时间。在犬右房置入电极,快速起搏右心房,诱发房颤并维持2小时。在起搏前后分别测定有效不应期（AERP）。结果：房颤后对照组AERP显著缩短,AERP频率适应性下降（P〈0．05）;而NAC组房颤前后AERP和AERP频率适应性均无明显变化。结论：在心房快速起搏致房颤2h的模型中,NAC对心房电重构具有明显的保护作用。     

Resistance and facilitation gradient in synchronized cardiac stimulation in the dog]

Electrical stimulation synchronized on spontaneous or paced cardiac rhythms demonstrates, in dogs : 1) phenomena of intermittent capture (I.C.), and intermittent loss (I.L.) of control, at all moments in the idastole ; 2) constant lowering of Excitability Threshold (E.T.) and Pacing Threshold (P.T.). These experiments confirm the existence of Resistance Gradients (including I.C. and I.L. phenomena) and Facilitation Gradients (measuring E.T. and P.T. lowerings). These gradients -- that we previously described in human pacing -- are parameters of the cardiac excitability.     

Overdrive pacing of early ischemic ventricular tachycardia: evidence for both reentry and triggered activity

Entrainment can be a useful method to identify reentry as a mechanism of ventricular tachycardia (VT). In this study, we evaluated the effect of gradually decreasing cycle lengths of overdrive pacing for stable VT induced in a canine model 1-3 h after coronary occlusion. Intact dogs underwent anterior descending coronary artery occlusion after instrumentation of the risk zone with 21 multipolar plunge needles, each recording 6 bipolar electrograms. Overdrive pacing was attempted if the animals had sustained hemodynamically stable VT, looking for evidence of entrainment. Subsequent three-dimensional mapping determined the mechanism of VT. Fifteen of the 21 dogs studied demonstrated entrainment with overdrive pacing by progressive QRS fusion alone (1), the first nonpaced QRS entrained to the paced cycle length only (7), or both (7). Five of these 15 dogs also had postpacing acceleration of the VT at a subsequent faster pacing cycle length. The mechanism of acceleration in four was a change to a VT with a focal origin. The prepacing mechanism in all 15 dogs was subsequently mapped to reentry. Regarding the six VTs, which demonstrated no evidence for entrainment, the site of earliest activity was mapped to a focal origin in all. These data showing entrainment of inducible reentrant VTs and lack of such for focal VTs support that the focal VTs seen in this study are unlikely the result of microreentry but possibly a mechanism as triggered activity.     

Conditioning shelter dogs to sit

Human contact in the shelter may lessen effects of change in environment and smooth transition into a home. Training can increase a dog's interaction with people in a shelter environment. Experiments were conducted to determine how rapidly shelter dogs learn to sit, if the dogs can retain sitting behavior over time, and if sitting transfers to novel locations and people. Two experiments trained shelter dogs (n = 21) to sit when a stranger approached over a 10-trial session. Food and a verbal cue or a clicker reinforced the sit. The experiments measured latency to sit for each trial. Latency to sit decreased significantly over trials. Another experiment included reinforcement given to dogs (n = 20) on a noncontingent basis or for sitting. Five days of the experiment (condition training) were in the same room with the same experimenter. The last 4 days (testing) varied by both experimenter and location (familiar or strange). Results indicate that short training sessions are effective for teaching shelter dogs to sit, that dogs can retain sitting behavior over 2 days, and that training transfers to novel people and situations.     

Clinical application of pacemakers in atrial tachyarrhythmias

The diagnostic programmes of modern pacemakers have increased our knowledge of atrial tachyarrhythmias (ATAs) in chronically paced patients. These programmes also support the evaluation of the effects of pharmacological treatment of ATAs. The success of interruption and/or prevention of ATAs with pacemakers depends strongly on the diagnostic accuracy and the properties of the pacing algorithms, their individual programming and the site and configuration of the pacing leads. Atrial septum pacing can be beneficial in patients with paroxysmal atrial fibrillation and prolonged P wave duration. Recent large-scale studies on preventive and interruptive atrial pacing of ATAs show modestly positive or no results. Therefore, atrial pacing therapy for ATAs should be considered cautiously, serving as an adjuvant to pharmacological treatment rather than as a primary intervention. This also applies for pacing interventions for ATAs in cardiac resynchronisation therapy. The pacemaker algorithms for the detection of ATAs and atrial lead configuration are crucial for the success of pacemaker-mediated prevention or interruption of ATAs. The success of these interventions is dependant on future improvements of pacemaker technology. (Neth Heart J 2008;16 (suppl 1): S20-S24.)     

Comparison of contractile function of diaphragm and cardiac muscle in response to paired electrical stimulation

Paired pacing has been shown to potentiate contractile function of cardiac muscle, and it has been suggested that this may enhance contractile function of diaphragmatic muscle. The primary goal of this study was to study the effect of paired pacing on potentiation of contractile function of diaphragmatic muscle compared to atrial and ventricular myocardium. Diaphragmatic muscle was isolated from mouse and rat, and atrial and ventricular myocardium from dogs. Potentiation was induced by isolated extrastimuli (equal in duration and intensity to the pacing stimulus) and by repetitive extrastimuli (i.e. paired pacing) at a paced rate of 12, 30 and 60 beats/min. Baseline studies were performed while preparations were isometrically contracting at L(max) in oxygenated Krebs-Henseleit solution at 28 degrees C. Maximal force generation in response to a premature stimulus was determined at each rate by scanning the coupling interval between paced beats. Under baseline conditions, diaphragmatic muscle contracted faster than atrial and ventricular muscle. In all tissues, maximum potentiation (increase in force above baseline) was approximately 100% of baseline force, and peak potentiation occurred at shorter coupling intervals with increasing rates of stimulation. Single and paired pacing of diaphragm potentiated the contraction during which the extrastimuli were introduced, while in cardiac muscle, extrastimuli potentiated the contraction following the extrastimulus. The maximum potentiated response occurred when the extrastimulus was introduced prior to the development of peak force in diaphragmatic muscle. In contrast, in atrial and ventricular muscle, a single or paired premature stimulus potentiated the subsequent beat when delivered late during relaxation. In cardiac muscle, maximal potentiation gradually occurred following several repetitive stimuli. Following cessation of single and paired pacing, the beat following the potentiated response immediately returned to baseline in diaphragmatic muscle, while a gradual decline was evident over several subsequent beats in cardiac muscle. Increasing the bath temperature from 28 to 37 degrees C resulted in a leftward shift in the peak potentiated force vs. coupling interval curve without a decline in the magnitude of potentiated force in diaphragmatic muscle. In diaphragm muscle, exposure to ryanodine markedly decreased baseline force and maximal potentiation. We conclude that closely timed extrastimuli applied to diaphragmatic muscle can potentiate developed force in a given contraction, while in cardiac tissue a delayed stimulus potentiates the subsequent beat. These differences in contractile responsiveness are not due to differences in loading conditions, but appear to reflect intrinsic differences in calcium handling.     

右室间隔部起搏患者起搏QRS 波时限与心功能的关系

目的:探讨右室间隔部起搏患者起搏QRS波时限与心功能的关系。方法:回顾性分析植入右室间隔部起搏的双腔起搏器患者(111例),起搏器平均植入时间(4.52±3.65)年,通过常规体表心电图测得完全起搏时QRS波时限分为四组:A组为QRS≤120ms(21例);B组为120ms180ms(26例),行心脏彩色多普勒检查获取左房内径(LAD)、收缩末期左室内径(LVESD)、舒张末期左室内径(LVEDD)、室间隔厚度(IVST)、左室后壁厚度(LVPWT)及LVEF,同时检测患者的血清氨基末端脑肭肽前体(NT-proBNP),分析起搏QRS波时限与以上各指标的关系。结果:D组患者LAD、LVEDD、LVESD、IVST及IVPWT较其他三组明显增大,同时LVEF显著下降,NT-proBNP明显升高,有统计学意义(P<0.05)。同时发现随起搏QRS时限的不断增宽,不同组别的LVEF是依次降低(中位值分别为66.5%、60.3%、52.7%和45.8%),而血清NT-proBNP水平是依次增大(中位值分别为143.7 pg/ml、261.8 pg/ml、599.4 pg/m和971.2 pg/ml)。直线相关性分析示起搏QRS波时限与LAD(r=0.141,P<0.05)、LVEDd(r=0.678,P<0.05)、LVEDs(r=0.439,P<0.05)、IVST(r=0.165,P<0.05)及LVPWT(r=0.189,P<0.05)有显著线性关系,呈正相关。起搏QRS波时限与LVEF负相关(r=-0.684,P<0.05),起搏QRS波时限与NT-proBNP的对数正相关(r=0.368,P=0.029)。结论:对于右室间隔部起搏的双腔起搏患者,起搏QRS波时限是一个可初步判断心脏结构和功能的指标,其起搏QRS波时限延长可能会恶化患者的心脏结构及功能,可结合NT-proBNP进行动态观察,对起搏器植入患者的心功能恶化和心衰的预防有一定的临床实用价值。     

犬腋下小切口制作慢性心房颤动模型

目的探讨应用腋下小切口开胸术建立犬慢性心房颤动模型的可行性。方法取健康比格犬14只,随机分为实验组(7只)与对照组(7只)。应用左侧腋下小切口微创技术开胸植入起搏器,实验组犬以400次/分连续起搏8周诱导心房颤动,对照组不起搏。术后观察犬的一般情况,定期监测心电图,记录犬的肢体导联心电图变化,观察心房颤动的发生情况。结果14只犬均顺利完成实验。应用左侧腋下小切口微创技术开胸,手术时间缩短,术后并发症减少。实验组7只犬经连续起搏8周,均出现典型的心房颤动心电图改变。结论应用腋下小切口微创技术开胸制作犬慢性房颤模型是安全可行的,犬术后无手术死亡及严重并发症,恢复快。说明与常规切口开胸手术相比创伤明显减小,值得在犬慢性房颤模型建立中推广应用。