For ease of illustration, I just wanted to bring this
up in this model. As you can see, here is a model of the heart.
Here are the lungs. This is the left ventricle or the main pumping
chamber of the heart itself. This is what we talk about getting enlarged
when the heart begins to fail, starting the syndrome of congestive heart
failure. So as you can see, this chamber is finite. When the
heart begins to fail because it can't pump enough blood to the whole body,
one of the compensations that happens is the hearts, since it can't pump
efficiently as a muscle and the pump function decreases, it begins to dilate.
It begins to enlarge. This muscle stretches way out. So, instead
of the heart looking this big, it becomes twice its size, displacing the
lungs. As a consequence, since there is a bigger volume, it can pump
the same amount of blood, but at a cost. When the blood starts to
backup in the heart itself, then it starts backing up into the other organs,
such as the lungs, such as the liver, such as the legs, forming the syndrome
of congestive heart failure. That's what congestion means.
Blood is backing up rather than going forward.
PAUL J. MONIZ, MD: What's interesting in this whole
discussion is that the body has the ability to compensate as it does.
In some cases, this is a bad thing because it can make a patient think
that nothing is wrong. Let's first take the kidneys. What happens,
Dr. Maybaum, with the kidneys.
SIMON MAYBAUM, MD: The kidneys see that the heart
is not efficiently supplying them with blood. It thinks that, in
some respects, there is too little blood on board. Even though there
is a normal amount of blood on board, it's just not flowing normally.
So, the kidneys work to absorb more fluid. That just exacerbates
the problem, so you get increased fluid retention, which is a compensatory
mechanism that is inappropriate in the setting of heart failure.
In fact, a lot of the medications work to regulate that compensatory mechanism.
