Article, see p 1015

It’s tough to make predictions, especially about the future.

—Yogi Berra

A 22-year-old man was initially diagnosed with hypertrophic cardiomyopathy (HCM) at 19 years of age during longitudinal family screening. He had been fit, active, and without cardiovascular symptoms or limitations. There was no family history of sudden death. He completed 18 minutes on a standard Bruce exercise test with normal heart rate and blood pressure response. Maximal left ventricular wall thickness was 17 mm; there was no resting or exercise-provoked obstruction; the left atrial size was normal; and no ventricular ectopy was identified on ambulatory monitoring. Three years after the initial diagnosis, without change in any clinical features, he had a cardiac arrest while walking to the subway.

Sudden death events in patients with HCM are rare, stochastic, and typically dissociated from premonitory changes in cardiac symptomatology, function, or morphology. Traditional risk predictors have low individual sensitivity and specificity. As a result, identifying patients who are at an increased risk for sudden cardiac death (SCD) remains a major clinical challenge. The stakes are high because, although implantable cardioverter-defibrillators (ICDs) can largely prevent SCD, they do not improve quality of life, and the long-term risks are real. The cumulative burden of infections, lead fractures, inappropriate shocks, and other complications will be particularly experienced by patients with HCM, who are usually younger than are other patients receiving ICDs and thus will potentially live with their devices for decades.

Large cohorts and iterative randomized controlled trials …

文章，请参阅第1015页

很难做出预测，尤其是对未来的预测。

瑜伽士贝拉（Yogi Berra）

在纵向家庭筛查中，一名22岁的男性最初被诊断出患有肥厚型心肌病（HCM），年龄19岁。他身体健康，活跃，没有心血管症状或限制。没有猝死家族史。他完成了18分钟的标准布鲁斯运动测试，心率和血压反应正常。左心室最大壁厚为17毫米；没有休息或运动引起的阻塞；左心房大小正常；在动态监测中未发现心室异位。初步诊断三年后，他没有任何临床特征的改变，他走路去地铁时心跳骤停。

HCM患者的猝死很少见，随机发生，通常与心脏症状，功能或形态的先兆变化无关。传统的风险预测因子具有较低的个体敏感性和特异性。结果，确定罹患心源性猝死（SCD）风险增加的患者仍然是主要的临床挑战。风险很高，因为尽管植入式心脏复律除颤器（ICD）可以在很大程度上预防SCD，但它们并不能改善生活质量，并且存在长期风险。感染，铅骨折，不适当的电击和其他并发症的累积负担将特别受到HCM患者的影响，他们通常比接受ICD的其他患者年轻，因此可能会与他们的设备一起生活数十年。

大型队列研究和迭代随机对照试验…