International Circulation:  Some of your research involves identifying patients with increased risk for cardiac arrest and to improve technology of these implantable defibrillators.  What is the status of some of the latest research and some of the latest developments?   Where is the field heading in your opinion?

    《国际循环》：您主要从事高危心脏骤停患者的临床识别和提高ICD技术工作。能否谈谈您在临床的最新研究和心得？ICD技术的最新发展如何？

    Bruce Lindsay:  This leads us to the question of can we really improve risk stratification?  This really applies to people who would get primary prevention devices， that is， those who have never had a cardiac arrest.  Over the years many attempts have been made to identify who will have a cardiac arrest and who won’t.  Beginning with signal-to-average DCGs， heart rate variability， various types of autonomic analysis， and T-wave alternates， unfortunately none of these have held up to be accurate predictors.  While they identify greater risk in populations of patients， in most instances their positive predictive value is low with a lot of false positives.  It seems as though they really haven’t solved the problem for us and so we continue to look at ways of either taking combinations of measures to try to stratify risk.  Part of the problem is that the substrate changes over time.  No matter what we do at one point in time， it is difficult to predict the future.

   Bruce Lindsay教授：这对我们提出一个问题：我们能否真正改进危险分层？这主要用于一级预防中选择哪些患者植入ICD，即那些尚未出现心脏骤停的人。多年来我们进行了许多尝试，以期确定那些患者将会发生心脏骤停，而哪些不会。从signal-to-average DCG起，到心率变异性、不同类型的自主神经活动分析及T波电交替等，不幸的是他们均不是准确的预测因素。当他们表明患者中的一部分人群有更高的危险时，通常其阳性预测值较低，且有很多假阳性。看来他们未能真正解决问题，因此我们继续寻找其他途径，或者联合应用多个指标，或者尝试危险分层。部分问题是事物随时间而改变，无论我们此时此刻做什么，未来都是很难预测的。