心臓的功能就是按照全身各组织的需要,及时排出足够的血液。当心臓不能满足这种需要时,即说明已进入心力衰竭状态。心臓的代偿能力在正常的情况下,如组织需要的血量增加,心臓能很快地增加排血量,以适应需要。这主要依靠两种代偿方式:一为增加心率,由于每分钟的心率增加,心臓每分钟的排血量也得到了增加;另一为增加心缩排血量,如仅仅依靠每分锴心率的增加,心排血量的增加还是有限的。因此尚需增加每次心臓收缩时的排血量, The function of heart 就 is in accordance with the needs of the body tissues, timely discharge of enough blood. When your heart can not meet this need, you are in a state of heart failure. The compensatory capacity of the heart 在 Under normal circumstances, such as the organization needs to increase the amount of blood, heart 臓 can quickly increase the amount of bleeding to meet the needs. This depends mainly on two compensatory methods: one is to increase heart rate, heart rate per minute because of increased heart rate, heart rate per minute has also been increased; the other is to increase cardiac output, such as relying solely on heart rate per minute The increase of cardiac output is still limited. So still need to increase the volume of blood transfusions when each heart contraction,