Systo-diastolic coupling as a therapeutic target for heart failure with preserved ejection fraction

传统上，心脏在全身泵血的好坏是通过心脏在每次心跳时排出的血液分数--射血分数来衡量的。现在人们了解到，即使射血分数在正常范围内，一个人仍然可能出现严重的心力衰竭症状，如呼吸急促，他们的预期寿命可能会缩短。这种射血分数保留的心力衰竭还不是很清楚，也很少有专门的治疗方法。我们最近的研究表明，这种形式的心力衰竭是由于心脏挣扎着收缩，因此在每次心跳期间，它必须收缩得更慢，持续更长的时间，才能进行与正常心脏相同的泵血量。检测这一点的关键是测量每一次心跳开始时心脏收缩的程度-第一阶段射血分数。在这个项目中，我们将确定这种新的测量方法如何依赖于每次心跳时返回心脏的血液量以及心脏所承受的压力。这将告诉我们如何最好地利用已知影响这两个因素的现有药物来治疗射血分数保持不变的心力衰竭。它还将有助于找到治疗这种类型心力衰竭的新方法。

How well the heart works to pump blood around the body has traditionally been measured by the fraction of blood the heart pumps out with each heartbeat - the ejection fraction. It is now understood that, even if their ejection fraction is in the normal range, a person can still develop serious symptoms of heart failure like shortness of breath and their life-expectancy may be reduced. This form of heart failure with preserved ejection fraction is not well understood and few specific treatments for it are available. Recent work by us suggests that this form of heart failure is due to the heart struggling to contract so that, during each heartbeat, it has to contract more slowly for longer to do the same amount of pumping as a normal heart. The key to detecting this is to measure how well the heart contracts at the very beginning of each heart beat - the first-phase ejection fraction. In this project we will determine how this new measurement depends on the amount of blood that returns to the heart with each heart beat and the pressure that the heart has to push against. This will then tell us how we might best use existing medicines that are know to affect these two factors to treat heart failure with preserved ejection fraction. It will also help identify new treatments for this type of heart failure.