N-of-1 for Beta-Blockers in Cardiac Amyloidosis

"The intervention is a single-arm crossover withdrawal/reversal design (On vs Off) with 2 total periods, each period lasting between up to 6 weeks. During the On period, subjects will be on their beta blocker. During the Off period, their beta blockers will be down-titrated by 50% each week and until subsequently discontinued (or the lowest dose the subject can safely tolerate).~Other Names:~* acebutolol~* atenolol~* betaxolol~* bisoprolol~* carvedilol~* labetalol~* metoprolol succinate~* metoprolol tartrate~* nadolol~* nebivolol~* penbutolol~* pindolol~* propranolol"