PULSUS PARVUS ET TARDUS REVEALS FLOW PROBLEMS IN AORTIC STENOSIS
A lot of attention is paid to the murmur of aortic stenosis, and there are certainly some interesting and informative nuances to this examination from a diagnostic perspective. However, the pulse examination in one respect is actually even more informative. It tells whether there is evidence of a problem with forward flow.
The classic pulse in aortic stenosis is termed “pulsus parvus et tardus.” Parvus is Latin for weak though it is not clear how specific this is as a physical diagnostic sign. Patients vary in their pulse intensity.
“Tardus” is latin for slow or late. This is an important finding. Because the word is a cognate of tardy, most textbooks emphasize delay. The original Latin apparently also means slow, and refers to a slow upstroke of the pulse itself. This is where the “parvus” is worth preserving. If a patient has a pulse contour that appears weak and prolonged then this is “parvus et tardus” and is a sign of impaired flow.
The delay is probably what is easiest to discern. Listen to S1 at the apex and compare the palpated carotid pulse to the heart sounds. Is there a delay? If so, there is a significant flow limitation. This delay can also be discerned by palpating the radial artery, as Yoshioka showed in 2010.
I would be curious to know whether having the patient exercise might bring out a flow problem that was previously subclinical.
Take home points:
Pulsus parvus et tardus reveals flow limitations in aortic stenosis.