Myles Paul S
J Extra Corpor Technol. 2014 Mar;46(1):23-7.
The most common cardiac surgical procedures are coronary artery bypass graft surgery and aortic or mitral valve repair or replacement. Underlying conditions include coronary artery disease and heart failure, manifesting as exertional angina, dyspnea, and poor exercise tolerance. The major goals of surgery are to alleviate symptoms and improve patient survival. These, therefore, should inform the choice of primary outcome measures in clinical studies enrolling patients undergoing cardiac surgery. Studies focusing on surrogate outcome measures are relied on all too often. Many are of questionable significance and often have no convincing relationship with patient outcome. Traditional "hard endpoint" outcome measures include serious complications and death with the former including myocardial infarction (MI) and stroke. Such serious adverse outcomes are commonly collected in registries, but because they occur infrequently, they need to be large to reliably detect true associations and treatment effects. For this reason, some investigators combine several outcomes into a single composite endpoint. Cardiovascular trials commonly use major adverse cardiac events (MACEs) as a composite primary endpoint. However, there is no standard definition for MACE. Most include MI, stroke, and death; others include rehospitalization for heart failure, revascularization, cardiac arrest, or bleeding complications. An influential trial in noncardiac surgery found that perioperative beta-blockers reduced the risk of MI but increased the risk of stroke and death. Such conflicting findings challenge the veracity of such composite endpoints and raise a far more important question: which of these endpoints, or even others that were unmeasured, are most important to a patient recovering from surgery? Given the primary aims of cardiac surgery are to relieve symptoms and improve good quality survival, it is disability-free survival that is the ultimate outcome measure. The question then becomes: what is disability and how should it be quantified after cardiac surgery?
最常见的心脏外科手术是冠状动脉搭桥术以及主动脉或二尖瓣修复或置换术。潜在病症包括冠状动脉疾病和心力衰竭，表现为劳力性心绞痛、呼吸困难和运动耐量差。手术的主要目标是缓解症状并提高患者生存率。因此，这些目标应指导纳入接受心脏手术患者的临床研究中主要结局指标的选择。过于频繁地依赖关注替代结局指标的研究。许多此类指标的意义存疑，而且往往与患者结局没有令人信服的关联。传统的“硬终点”结局指标包括严重并发症和死亡，前者包括心肌梗死（MI）和中风。此类严重不良结局通常在登记处收集，但由于它们发生频率低，需要大量样本才能可靠地检测到真正的关联和治疗效果。因此，一些研究人员将多个结局合并为一个单一的复合终点。心血管试验通常将主要不良心脏事件（MACE）用作复合主要终点。然而，MACE没有标准定义。大多数包括MI、中风和死亡；其他还包括因心力衰竭再次住院、血运重建、心脏骤停或出血并发症。一项在非心脏手术领域有影响力的试验发现，围手术期使用β受体阻滞剂可降低MI风险，但会增加中风和死亡风险。此类相互矛盾的研究结果对这些复合终点的真实性提出了挑战，并引发了一个更重要的问题：对于从手术中恢复的患者而言，这些终点指标中的哪一个，甚至其他未测量的指标，最为重要？鉴于心脏手术的主要目的是缓解症状并提高高质量生存率，无残疾生存才是最终的结局指标。问题就变成了：什么是残疾以及心脏手术后应如何对其进行量化？
