As Bypeep said, they are excellent for palps occuring with stress, adrenaline, caffeine, high heart rate
, (that's my personal experience too) but they significantly reduce the heart rate and
can cause more bradycardia-induced PVCs (and PACs).
Nadolol works the same way as propranolol by the way, they are both nonselective.
In my experience, nonselective beta blockers are better to manage anxiety-induced palps, and they also remove some anxiety.