REN and orthostatic hypotension: Medical treatment of heart failure (HF) in transthyretin cardiac amyloidosis (ATTR-CA) has been limited primarily to loop diuretics and mineralocorticoid receptor antagonists due to intolerance of other agents with proven benefits, including cardio-selective beta blockers, renin-angiotensin-aldosterone system inhibitors, and angiotensin receptor neprilysin inhibitors that may potentiate the risk for orthostatic hypotension.