A root, minor 3rd, 5th and flat 7 makes up a minor 7 chord/arpeggio.
A C E G
R m3 5th b7
Here's a bonus - because Dmin7 and Emin7 chords are both in the key of C major/A minor, you can play the exact same patterns for those arpeggios as well. This fact makes the arpeggio picking shapes extra useful.
Here is a descending run which I created by blending the Dmin7 and the Emin7 shapes together:
To hear these shapes in action (+ some bonus music theory) check out the video I made for this lesson:
By Alfred Potter www.AlfredPotter.com