Fig 1. Pre-ejection period.
A, electrocardiogram; B, Doppler mode echocardiography signal over the aortic valve; C, photoplethysmographic pulse wave. PEP = pre-ejection period, VTT = vascular transit time, PTT = pulse transit time.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.