Step II Pulses Bisferiens

[iBS1972]

Can anyone explain the physiology behind pulses bisferiens (biphasic pulse)? Uworld says it's when you have 2 strong systolic peaks with a midsystolic dip, and occurs in significant aortic regurication, HOCM, and large PDAs. Anyone know what's happening that's causing this type of pulse?

 

[tvelocity514]

From uptodate:
Pulsus Bisferiens: "The normal carotid arterial pulse tracing and the central aortic pulse waveform consist of an early component, the percussion wave, which results from rapid left ventricular ejection, and a second smaller peak, the tidal wave, presumed to represent a reflected wave from the periphery. The tidal wave may increase in amplitude in hypertensive patients or in those with elevated systemic vascular resistance. Radial and femoral pulse tracings demonstrate a single sharp peak in normal circumstances.

Pulsus bisferiens is characterized by two systolic peaks of the aortic pulse during left ventricular ejection separated by a midsystolic dip. Both percussion and tidal waves are accentuated. It is difficult to establish with certainty that the two peaks are occurring in systole with simple palpation (pulsus bisferiens) versus one peak in systole and the other in diastole (dicrotic pulse)."

 

[iBS1972]

From uptodate:
Pulsus Bisferiens: "The normal carotid arterial pulse tracing and the central aortic pulse waveform consist of an early component, the percussion wave, which results from rapid left ventricular ejection, and a second smaller peak, the tidal wave, presumed to represent a reflected wave from the periphery. The tidal wave may increase in amplitude in hypertensive patients or in those with elevated systemic vascular resistance. Radial and femoral pulse tracings demonstrate a single sharp peak in normal circumstances.

Pulsus bisferiens is characterized by two systolic peaks of the aortic pulse during left ventricular ejection separated by a midsystolic dip. Both percussion and tidal waves are accentuated. It is difficult to establish with certainty that the two peaks are occurring in systole with simple palpation (pulsus bisferiens) versus one peak in systole and the other in diastole (dicrotic pulse)."

Thank you so much for your reply. That clears things up a little bit. Would you happen to know what "reflected wave from the periphery" means/could you dumb it down one more level? haha

Edit: I'm surprised that uptodate has something specifically about pulses bisferiens.

 

[tvelocity514]

Thank you so much for your reply. That clears things up a little bit. Would you happen to know what "reflected wave from the periphery" means/could you dumb it down one more level? haha

Edit: I'm surprised that uptodate has something specifically about pulses bisferiens.

Haha no worries:
Eg. for Hypertrophic CM: The MV leaflet doesn't get pulled into the LVOT until after the AV valve opens, so the initial upstroke of the arterial pulse pressure will be normal. When the MV leaflet gets pushed into the LVOT, the arterial pulse collapses (bc the MV isn't closed to keep that pressure gradient), followed by a second rise in the pulse pressure, as the LV pressure overcomes the increased obstruction caused by the systolic anterior motion of the MV.

Hopefully this helps!