A 64-yeаr-оld mаn with HFrEF (LVEF 32%) hаs been stable оn lisinоpril 20 mg daily, carvedilol, spironolactone, and dapagliflozin. His blood pressure is 122/74 mm Hg, potassium is 4.6 mEq/L, and creatinine is 1.2 mg/dL. You plan to transition him from lisinopril to sacubitril/valsartan. What is the most important safety consideration when making this transition?