左心辅助循环应用初探

探讨左心辅助循环于心脏术后顽固性左心衰竭的应用效果。５例术后顽固性左心衰竭病人，经左心房－辅助泵－右髂外动脉，建立左心辅肋循环。结果见５例病人均脱离人工心肺机，２例存活出院。并发症有出血、感染及多器官功能衰竭。作者认为，左心辅助循环疗效肯定，关键在于及时果断应用。     

左心转流在心脏直视术后的应用

目的 总结左心转流抢救心脏直视术后重度低心排血量的经验。方法 5例心瓣膜置换术患者术后发生顽固性低心排血量，应用Delphin Ⅱ型离心泵，经左心房－房心泵－主动脉或股动脉建立左心转流辅助循环。结果 5例均顺利脱离左心辅助，1例因心律失常早期死亡，2例晚期分别死于右心功能不全、多器官功能衰竭，2例痊愈出院。结论 重度低心排血量患者及时果断应用左心辅助，疗效确切，防止左心转流并发症，改善术后右心功能是提高左心转流成功率的关键。     

左心辅助循环治疗术后顽固性左心衰竭的体会

辅助循环是治疗顽固性心力衰竭的外科方法 ,其中最常用的是左心辅助循环治疗顽固性左心衰竭[1] 。 1993年12月～ 1999年 10月 ,我科为 13例心内直视手术后顽固性左心衰竭患者施行了左心辅助循环手术。现报告如下。1.临床资料 :本组 13例中 ,男 6例 ,女 7例 ;年龄 10～ 6 4岁。重症紫绀型法乐四联症 (Ｆ4)纠治术ｌ例 ,二尖瓣重度狭窄小左心室行二尖瓣替换术 (ＭＶＲ)后ｌ例 ,重症冠状动脉搭桥术 (ＣＡＢＧ)后 3例 ,主动脉瓣重度狭窄行主动脉瓣环扩大主动脉瓣替换术 (ＡＶＲ)后ｌ例 ,左室血栓 (心肌梗塞后 )摘除及冠状动脉旁路移植术后ｌ例 ,…     

主动脉内球囊反搏联合离心泵左心辅助治疗严重低心排血量综合征

目的：总结主动脉内球囊反搏(IABP)联合离心泵左心辅助治疗严重低心排血量综合征(LCOS)的经验。方法：2000～2004年,于北京大学第一医院心脏外科行冠状动脉旁路移植(CABG)术后出现严重的LCOS5例,在大量应用血管活性药物治疗无效情况下,应用IABP联合离心泵行左心辅助。离心泵经右上肺静脉和升主动脉插管连接。结果：所有患者血流动力学明显改善,联合辅助4～7d后均顺利脱离离心泵。辅助期间5例均出现了不同程度的血液细胞破坏和急性肾功能不全,其中3例在离心泵撤除后肾功能逐渐恢复正常,痊愈出院;1例死于急性肾功能衰竭;1例死于多脏器功能衰竭。5例均需补充全血或浓缩红细胞,4例需补充血小板。结论：IABP联合离心泵进行左心辅助,能明显改善CABG术后大剂量血管活性药物无效的严重LCOS的血流动力学,副作用为血液细胞破坏和急性肾功能不全。     

自制左心辅助引流管道行左心辅助2例

左心辅助循环是治疗术后严重低心排的最有力措施之一。１９９５年９月至１９９６年９月我们使用自制左心辅助引流管道进行床旁左心辅助循环，对２例冠状动脉搭桥术后低心排病人进行左心辅助，现报道如下。临床资料２例重症冠心病病人均为男性，年龄分别为５８、５５岁。均...     

冠状动脉旁路移植术后左心辅助临床应用体会

目的：总结冠状动脉移植术（搭桥术）后使用左心机械辅助情况，为临床处理重症冠心病提供参考。方法：回顾分析了1704例搭桥术病人使用左心辅助的情况，并分析了其与并发症、病死率相关因素。结果：搭桥术病人左心机械辅助使用率为1.5％，脱机率76％，出院率48％。主要并发症为多发性器官功能衰竭（MOF）、出血等。死亡病人大多在脱机后发生，主要死因为MOF、肾功能不全、心功能衰竭。结论：搭桥术后左心机械辅助应强调早期使用，如有可能，小流量观察一段时间再停机。     

主动脉内球囊反搏在心脏手术中的运用与护理

主动脉内球囊反搏(简称IABP)是心脏手术左心辅助循环方法之一.我科1999年2～12月,对7例体外循环术中不能脱机和/或低心排综合征行IABP辅助后顺利停机,现报告如下.     

心脏手术围术期辅助循环的应用与管理

目的　总结心脏手术围术期应用辅助循环的经验。　方法　 13例患者 (左心室射血分数平均 0 .3 7± 0 .0 6)中行冠状动脉旁路移植术 10例 ,机械瓣膜置换术 2例 ,马方综合征 ( Marfan syndrome)患者行 Bentall手术 1例。术后不能脱离心肺转流 ( CPB) 9例 ,术后并发心肌梗死、严重室性心律失常和心脏骤停 4例 ,分别采用主动脉内球囊反搏 ( I-ABC)、转子泵或离心泵左心转流和体外膜肺氧合等辅助循环治疗。　结果　 6例存活出院 ,平均辅助循环时间 4 4 .0±3 2 .5小时。不能脱离 CPB的 9例患者 ,经辅助循环支持后 7例脱离 CPB,4例存活 ;在 ICU行辅助循环的 4例患者中 ,2例存活。　结论　辅助循环是治疗心脏手术后严重心力衰竭和室性心律失常的有效方法。     

787例老年患者非体外循环冠状动脉旁路术后循环、呼吸系统并发症的护理

目的探讨60岁及以上患者非体外循环冠状动脉旁路移植术(off-pump coronary artery bypass grafting,OPCABG)术后循环、呼吸系统的护理特点。方法回顾性总结分析787例年龄在60~85岁的OPCABG患者的临床资料,对循环、呼吸系统术后常见并发症的原因及护理进行分析探讨。结果循环、呼吸系统并发症是老年患者OPCABG术后常见病,多发病。787例老年患者术后循环、呼吸系统各种并发症总发生率高达90.47%。死亡15例,死亡率为1.91%,其中术后再次开胸止血并发肾功能衰竭死亡1例,低心排量综合征死亡1例,术后顽固性心律失常死亡2例,严重肺部感染引起多脏器功能衰竭综合征死亡11例。结论老年患者OPCABG术后循环、呼吸系统并发症的护理是术后护理的重点,对于患者顺利康复起着关键性的作用。     

心衰后胶原网架结构变化与左旋精氨酸保护作用的实验研究

目的：观察急性左心衰后心肌胶原网架结构的变化及左旋精氨酸（ＬＡｒｇ）对心肌细胞及间质的保护作用，进一步探讨心衰机制及围手术期心肌保护方法。方法：１６只犬随机均分为两组，通过心肌缺血再灌注损伤法制造急性左心衰模型，离心泵行左心辅助１２０分，辅助期间实验组加ＬＡｒｇ３００ｍｇ／ｋｇ，分别观察两组血流动力学、心肌超微结构、血浆ＥＴ１。结果：实验组在辅助循环期间室颤发生率及死亡率较低，生存时间长于对照组，ＥＴ１心衰后明显高于心衰前，辅助后实验组有所下降。心肌超微结构实验组优于对照组。结论：心肌胶原网架在急性心衰过程中起着重要作用，ＬＡｒｇ对急性缺血心肌及间质有保护作用。     

Cardioventilatory coupling in heart rate variability: methods for qualitative and quantitative determination

In this study we sought to develop quantitative methods fordetermining the presence of cardioventilatory coupling in rawheart rate time series. The beat-to-beat RR interval time seriesof 98 anaesthetized, spontaneously breathing subjects were representedgraphically as (1) raw RR interval time series, (2) RR consecutivedifference time series and (3) a phase portrait of the RR consecutivedifference time series. We then examined the relationships betweenthe presence of cardioventilatory coupling in these epochs andthe plot appearance and entropy measures derived from theseplots. We observed that coupling was significantly associatedwith the presence of banding in the raw heart rate and RR consecutivedifference time series, and with discrete clustering withinthe RR consecutive difference phase portrait. A significantcorrelation was found between coupling and the entropy of theRR consecutive difference time series and its phase portrait.We conclude that, with some provisos, these simple graphicaland derived quantitative measures provide a basis for the determinationof cardioventilatory coupling from heart rate time series. Br J Anaesth 2001; 87: 827–33     

Cardioventilatory coupling in heart rate variability: the value of standard analytical techniques

In a group of spontaneously breathing anaesthetized subjects,we examined the ability of simple spectral and non-linear methodsto detect the presence of cardioventilatory coupling in heartrate time series. Using the proportional Shannon entropy (H_RI–1)of the RI_–1 interval (interval between inspiration andthe preceding ECG R wave) as a measure of coupling, we foundno correlation between H_RI–1 and either the fractal dimensionor approximate entropy of the heart rate time series. We alsoobserved no difference in the distribution of heart rate variability(HRV) spectral power in three frequency ranges (high, 0.15–0.45 Hz;low, 0.08–0.15 Hz; very low, 0.02–0.08 Hz)between uncoupled epochs and coupling patterns I, III and IV.Because of its association with low breathing frequencies, patternII coupling epochs showed exaggerated low-frequency power asthe high-frequency ‘respiratory’ peak fell intothe low-frequency range. We conclude that coupling pattern islargely independent of autonomic tone and that these standardmethods of HRV analysis are limited in their ability to detectthe presence of cardioventilatory coupling in heart rate timeseries. Br J Anaesth 2001; 87: 819–26     

Cardiac Operations in Patients 90 Years of Age and Older

Background. Growth of the elderly population worldwide, and specifically in the United States, will continue to accelerate and will have a profound impact on the cost and delivery of health care resources in the future. A medical strategy that allows the elderly to live independently is essential to most cost-effective use of our resources. The question remains as to what will be the future of surgical therapy for this increasing population.

Methods. We retrospectively studied the cases of 30 consecutive nonagenarians (mean age, 92.3 ± 1.8 years) who underwent a cardiac operation within a 9-year period. All patients were in New York Heart Association class III or IV and underwent operation urgently or emergently.

Results. The 30-day mortality rate was 10%, and the actuarial survival rates were 81% ± 8% and 75% ± 9% at 1 year and 2 years, respectively. Seventy-eight percent of survivors were in New York Heart Association class I or II within 2 years after operation and had an improved quality of life. The cost of providing care in this age group was 24% higher than in octogenarians.

Conclusions. Advanced age in and of itself (>90 years) should not be a contraindication to an open-heart operation, although morbidity, mortality, and cost may be higher. However, selective criteria identifying risks and benefits for individual patients should be applied. The aging of our population will have a profound impact on the cost and delivery of health care resources in the future. This issue must be addressed in the current debate on the provision of expensive procedures under a realigned national health-care system.     

重症心不停搏双瓣置换术

本文介绍了心不停搏双瓣置换术的体外循环及手术技术。特别强调：①体外循环流量必须维持平均动脉压大于6.7kpa，预充液内加入少量去甲肾上腺素（1μm/kg）有助于提高灌注压。②33℃浅低温有利于心脑等重要脏器保护和手术操作。③主动脉瓣转换时，冠状静脉窦送行灌注流量在200-300ml/min之间。④左心术毕，注意充气排气。     

无支架带腱索支持生物心脏瓣膜的研究

为研制无支架带腱索支持生物心脏瓣膜并对其血流动力学及抗钙化性能进行评价,试验选用年幼绵羊9只,新鲜牛心包经98％甘油鞣制后,缝制成21mm无支架生物瓣,在常温体外循环下行绵羊二尖瓣替换。术后不抗凝,2～8个月后择期行心导管,左室造影及病理检查。结果表明:全组无血栓、栓塞或感染。8例于术后168.4±55.3天,经血流动力学检测:平均跨瓣压差0.76±0.20kPa,有效瓣口面积1.9±0.75cm~2,心脏指数104.1±38.7ml/kg/min;瓣膜无关闭不全或轻度关闭不全者各3例,中度关闭不全者2例。瓣膜病理检查:仅2例有中度钙化,6例轻度钙化。电镜扫描示7例有内皮细胞覆盖生长。1例于术后220天死于心衰,为瓣膜交界处缝线松脱,产生关闭不全所致;其瓣膜表面光泽、柔软,无任何增厚或钙化灶。提示该无支架带腱索支持生物心脏瓣膜的血流动力学及抗钙化性能均满意。     

Tissue heart valve implantation in India; Indications, results and impact on quality of life

Backgound There is limited experience with bioprosthetic heart valve implantation in India and results and follow-up are not available. This study aims to assess the suitability of the bioprostheses in the Indian population and impact on their quality of life. Patients and Methods Between January 2000 and December 2006, 457 patients underwent bioprosthetic valve replacement. Their age ranged from 20–77 years with a mean age of 55.5±9.3 years. A total of 559 bioprosthesis were implanted: of these 200 (43%) were mitral valve replacements (MVR), 154 (33.7%) aortic valve replacements (AVR), 102 (22.3%) double valve replacements (DVR) and one(0.2 %) tricuspid valve replacement (TVR). Results There were 11 (2.4%) early and 3 late deaths (0.7%). Post-operative gradients were low. Actuarial survival at 60 months was 95.1±2.2%. The actuarial event free survival was 87.9±5.7% at 60 months. Advantages were freedom from thromboembolism (97.6%), infective endocarditis (98%), haemorrhage (99.7%), Paravalvular leak (99.3%), valve dysfunction (100%) and re-operation (100%). Assessment of quality of life using the standard World Health Organization questionnaire for quality of life yielded satisfactory results. Conclusions Bioprosthesis are particularly suited for older age patients in our country and are associated with a good quality of life. However long-term results on valve function are awaited.     

Long-Term In Vivo Left Ventricular Assist Device Study for 284 Days with Gyro PI Pump

A totally implantable centrifugal artificial heart has been developed. The plastic prototype, the Gyro PI 601, passed 2 day hemodynamic tests as a functional total artificial heart (TAH), 2 week screening tests for anti-thrombogenecity, and a 1 month system feasibility study. Based upon these results, a metallic prototype, the Gyro PI 700 series, was subjected to long-term in vivo left ventricular assist device (LVAD) studies of over 1 month. The Gyro PI 700 series has the same inner dimension and same characteristics of the Gyro PI 601 such as an eccentric inlet port, a double pivot bearing system, and a magnet coupling system. The PI metallic pump is also driven with the Vienna DC brushless motor actuator like the PI 601. The pump-actuator package was implanted in 3 calves in the preperitoneal space, bypassing from the left ventricular (LV) apex to the descending aorta. Case 1 achieved a 284 day survival. Case 2 was euthanized early at 72 postoperative days as a result of the functional obstruction of the inlet port due to the excessive growth of the calf. There was no blood clot inside the pumps of either case. Case 3 is on-going (22 days on July 24, 1998). During these periods, all cases showed no physiological abnormalities. In conclusion, the PI 700 series pump has excellent results as a long-term implantable LVAD.