Carotid Spectral Doppler Waveform in Heart Failure

The hemodynamics of advanced heart failure are quite complex. In this post, I present a visual demonstration of some of these changes by looking at the carotid artery spectral Doppler waveform in advanced heart failure.

To begin let’s look at normal.¬†The brain maintains a continuous supply of blood throughout the cardiac cycle. Thus, there is forward flow through systole and diastole in the carotid arteries. The spectral waveforms in the image below show this well. The brain does this by maintaining a low vascular resistance. Just like water finding the easiest path down hill, blood finds the easiest path to follow in the body. The brain makes it very easy for blood to flow into it; probably because it considers itself a vital organ.

Normal CCA spectral waveform. The flow continues throughout the cardiac cycle (from beat to beat) and never goes below the baseline (never reverses).

Normal CCA spectral waveform. The flow continues throughout the cardiac cycle (from beat to beat) and never goes below the baseline (never reverses).

In sharp contrast to normal shown above, in advanced heart  failure we can see a reversal of flow immediately after systole that is striking in appearance if you are accustomed to the normal waveforms.

The flow reversal is marked in this image. The triphasic waveform resembles peripheral vascular flow.

The flow reversal is marked in this image. The triphasic waveform resembles lower extremity peripheral vascular flow.

The post-systolic dip is still evident in the internal caroid artey; although there is no longer any significant flow reversal.

The post-systolic dip is still evident in the internal carotid artery; although there is no longer any significant flow reversal.

chf waveforms vert16_cropped

Not surprisingly, the post-systolic dip and flow reversal are present in the vertebral artery as well.

So, why do we see this waveform in advanced heart failure? Frankly, I don’t know for sure. I suspect it is a combination of effects including increased vascular stiffness and aortic valve dysfunction in dilated cardiomyopathy. Regardless, it is a good visual example of the altered hemodynamics of heart failure. I welcome your thoughts and ideas.

 

 

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>