Case 1: A 68-year-old female patient presents with fatigue, chest pain, palpitations, dyspnea, and syncope while performing normal physical activity. She is comfortable at rest, with limited impairment of functional status. She is categorized as having HFpEF NYHA Class II, with an LVEF of 58% and an eGFR of 61 mL/min/1.73 m2. She is currently taking ACE inhibitors and diuretics.
Case 2: A 65-year-old man is experiencing symptoms fatigue, chest pain, palpitations, dyspnea, and syncope with less than normal physical activity. He is comfortable at rest only, with limitations on functional status. He recently transitioned to HFpEF NYHA Class III, with an LVEF of 35% and eGFR of 58 mL/min/1.73 m2. He is currently taking an ARB, diuretic, and beta blocker.
In both patients, the addition of which agent would result in a relative risk reduction in time to cardiovascular death or hospitalization due to heart failure? Before prescribing this drug, in which patients should renal function and volume status be tested? What are the most common adverse reactions for this drug (i.e., occurring in ≥5% of patients)?