Visible apex beat including different type of apex beat - YouTube
MedicosNotes.com: What is the significance of apex beat
Apex beat
Apex beat | Medical knowledge, Nclex, Medicine
Apex Beat: The Most Up-to-Date Encyclopedia, News, Review & Research
Shashikiran Umakanth on Twitter: "Here's an algorithm to analyse the cardiac apex beat (PMI). My previous version of this algorithm is included in the Wikipedia page on apex beat, under Creative Commons