Watch the Minor Swing online guitar lesson by Robert Renman from Blues Booster
Because of the C# note in the chords, the Dorian scale is perfect. Now, playing over just one chord vamps can be boring. To open up the idea shed a bit, I utilize both the A and B Triads, Diminished scale, and the "skip the 2nd pattern". I also repeat a lick - this always makes it stick out more and the solo sounds more interesting.