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.
The shortening of the P‐P interval containing a QRS vs the timing of the interposed QRS. P‐P shortening ≤3% occurs randomly, whereas shortening more than 3% is seen predominantly when the QRS occurs in the first 60% of the anticipated P‐P interval. See text for details.
