心脏的新希望，本文主要内容关键词为：心脏论文，此文献不代表本站观点，内容供学术参考，文章仅供参考阅读下载。
For thousands of Americans suffering from diseased hearts,and for the doctors who treat them,it's been the most compelling yet elusive of goals for more than 50 years:an artificial heart whose machinery isn'tthe size of a refrigerator.Now that objective is no longer tantalizingly out of reach.Beginning this summer,five patients will betesting the first self-contained,completely implantable mechanical heart-a man-made organ no larger than grapefruit.
[2]Such an extraordinary device carries extraordinary risks,so these five recipients must meet stringent criteria,says Edward E.Berger,vice president of the device's developer,Abiomed（注：可能是由abiotic（生活力缺失的）与medicine缩合而造的一个专有名词，用作公司名称，不宜按字面猜想的意思译成中文。） of Danvers,Massachusetts."Their hearts must be so diseased,with both ventricles impaired,that they are projected to live no more than 30 days.And they cannot be eligible for a heart transplant."
[3]Each year more than 100,000 Americans would benefit from a new heart,estimates Abiomed,but the majority never even make it to the waiting list,as the number of donor hearts hovers around 2,000 annually.
[4]The quest（注：quest(for)n寻找；探索。）for an artificial heart dates back at least to the 1950s,when Willem Kolff implanted the firstmodel in animals.Almost 20 years later,Domingo Liotta placed a mechanical pumping device into a 47-year-old patient for three days,proving that such replacement organs could function,at least temporarily.In 1982,a patient named Barney Clark,who was suffering from a failing heart,swapped his own heart for a device called the Jarvik-7.Plagued（注：[pleig]困扰。）by medical and mechanical problems,Clark died after 112 days.In subsequent years,the Jarvik-7 helped keep more than 70 people alive while they waited for a transplant.But since patients were tethered to external compressed-air hoses to power the heart,the Jarvik-7 was never widely used as anything more than a short-term replacement.
[5] Abiomed's heart,called the AbioCor,is made primarily of titanium and proprietary polyurethane（注：
聚氨基甲酸脂；聚氨脂。）plastic.Sitting in the chest cavity,the 2-pound device consists of a motor-driven hydraulic pumping system that opens and closes two artificial ventricles.A miniaturized electronics package placed in the abdomen monitors and controls the heart's pumping speed based on the patient's needs.An internal rechargeable *lithiumion battery（注：锂离子电池。）and an external rechargeable battery pack power the system.
[6]"One critical element of the design,"says Berger,"is that the device be a totally sealed system,sothat nothing pierces the skin"-a principal source of dangerous postoperative infections and one of the main reasons mechanical hearts fail.The external battery continually charges the internal battery through a set of conducting coils.The internal unit powers the system for 30 to 45 minutes and its external partner,strapped to the patient's waist,can power the system for about 4 hours.
[7] Depending on how well the five patients do,others could soon follow.It is conceivable,says Berger,that Abiomed could get FDA（注：=Food & Drug Administration）approval to market the AbioCor within three years.Initially,the device would cost between $ 75,000 and $100,000 and the surgery would likely be priced about the same as a heart transplant.
[8]"We are certain,"Berger adds,"that when we reach our design goal of a five year life span for the AbioCor heart,the total cost to *the health care system（注：保健系统，指涉及医疗保健的所有环节）will be less than that of a heart transplant,because transplant patients require lifelong immune-suppressing（注：抑制免疫的。）medication,which is quite expensive."
对成千上万患有心脏病的美国人及治疗他们的医生来说，50多年来一直最吸引人而又最难以捉摸的目标就是：不像电冰箱机械装置那么大的人造心脏。现在这个目标不再可望而不可及了。从今年夏天开始，5位患者将试用第一种自身配备齐全的全植入式机械心脏——一种仅葡萄柚大小的人造器官。
[2]研制该装置的是位于马萨诸塞州丹弗斯的阿比奥莫德公司，公司副总裁爱德华·E·伯杰说，这样一种超常的装置会有超常的风险。因此，这5位患者必须符合严格的标准。“他们的心脏必须病得两个心室都受损，以致预计也就再活30天。而且他们不适合做心脏移植手术。”
[3]阿比奥莫德公司估计，每年有10万以上的美国人需要更换心脏的治疗，但是由于每年捐献的心脏总是在2000个左右，所以大多数人根本排不上号。
[4]对人造心脏的探索至少可以追溯到20世纪50年代，当时威廉·科尔夫在动物身上植入了人造心脏的第一个模型。大概20年以后，多明戈，利奥塔将一个机械泵装置在一位47岁的患者体内放了3天，证明这种替换器官能起作用，起码可以应急。1982年，一位名叫巴尼·克拉克的病人患有心力衰竭，医生用一种名叫Jarvik-7的装置替换了他的心脏。由于医疗和机械问题的困扰，克拉克在112天后死亡。在以后的若干年里，Jarvik-7帮助了70多人活着等待移植。但是由于病人要被拴在向心脏提供动力的体外压缩空气软管上，所以Jarvik-7除了作为短期替换使用之外，从没得到广泛使用。
[5]阿比奥莫德公司造的心脏叫“阿比奥科”，主要采用钛和专用的聚氨酯塑料制成。这种两磅重的装置放在胸腔内，有一套马达驱动的液压泵系统操纵着两个人造心室的开闭。一个放在腹内的微型电子组件，可根据患者的需要监控心脏的泵速。一个体内锂离子电池和一个体外可充电电池组为这个系统供电。
[6]伯杰说：“设计的一个关键因素是，这种装置是全封闭系统，因此无任何东西穿过皮肤。”这是一个主要的术后危险感染源，也是机械心脏出故障的主要原因之一。体外电池通过一套电线圈为体内电池连续充电。体内电池可为该系统供电30～45分钟，而缚在病人腰部的体外电池能为该系统供电约4小时。
[7]根据这5位患者的使用效果，其他人可能很快就会跟着做。伯杰说，阿比奥莫德公司预计在3年内“阿比奥科”可取得美国食品与药物管理局的批准上市。开始时它的价格将在7.5至10万美元之间，而手术费和心脏移植费差不多。
[8]伯杰又说：“我们可以肯定，当“阿比奥科”心脏达到我们设计的5年寿命目标时，保健系统的总成本会低于心脏移植，因为移植病人需要终生服用抑制免疫药物，这药物是相当贵的。”
标签：heart论文;