Watch this great video showing the Modified Valsalva Maneuver converting a patient in SVT to Normal Sinus Rhythm
If you’re not doing this, you’re not doing SVT right!
Video courtesy: @julesantosER
#FOAMed
If you’re not doing this, you’re not doing SVT right!
Video courtesy: @julesantosER
#FOAMed
In the REVERT Randomized Controlled Trial the success rate was 43% vs. 17% for the standard Valsalva Maneuver!
Read about it here: ncbi.nlm.nih.gov/m/pubmed/26314…
Read about it here: ncbi.nlm.nih.gov/m/pubmed/26314…
A lot people have asked about the physiologic explanation for why the Modified Valsalva Maneuver works. I’m gonna do my best to explain it as I understand it.
Let’s start by taking a look at the body’s physiologic response to valsalva...
Let’s start by taking a look at the body’s physiologic response to valsalva...
The valsalva maneuver initially causes a decrease in heart rate. But after about 5 seconds or so, the heart rate begins to rise. At around the 15 second mark, you can see that the heart rate has very significantly increased from baseline! 
The reason this happens is that with prolonged valsalva, there’s a significant ↓ in venous return, resulting in ↓ cardiac output, and ↓ blood pressure.
The body’s natural physiologic response to all of this, is to compensate with ↑ sympathetic drive and ↑ heart rate!
The body’s natural physiologic response to all of this, is to compensate with ↑ sympathetic drive and ↑ heart rate!
So this means that at around 15 seconds of sustained valsalva, the body is in a relatively sympathetic state.
This all results in a very significant INCREASE in conduction through the AV Node.
But this is the exact opposite of what we want! So how then does valsalva BREAK SVT?
This all results in a very significant INCREASE in conduction through the AV Node.
But this is the exact opposite of what we want! So how then does valsalva BREAK SVT?
The key is that SVT doesn’t break DURING valsalva. It breaks when valsalva is RELEASED.
When the patient stops blowing, the physiology is reversed. There’s a sudden ↑ in venous return, ↑ cardiac output, & ↑ blood pressure.
This results in Parasympathetic Overdrive!
When the patient stops blowing, the physiology is reversed. There’s a sudden ↑ in venous return, ↑ cardiac output, & ↑ blood pressure.
This results in Parasympathetic Overdrive!
The Modified Valsalva Maneuver simply enhances this process:
By laying the patient supine and raising their legs up immediately after they release valsalva, you’re effectively delivering a rapid endogenous “fluid bolus” of pooled venous blood right up to the heart!
By laying the patient supine and raising their legs up immediately after they release valsalva, you’re effectively delivering a rapid endogenous “fluid bolus” of pooled venous blood right up to the heart!
Already in parasympathetic overdrive from valsalva release, now the baroreceptors are really shocked! The sudden, dramatic vagal response results in a very powerful AV Nodal blockade!
And that is how the Modified Valsalva Maneuver terminates SVT.
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And that is how the Modified Valsalva Maneuver terminates SVT.
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