A 74-year-old woman with known heart failure with reduced ejection fraction presents with increasing breathlessness, orthopnoea and bilateral ankle oedema. She has gained 3 kg over the past week. On examination, she has bibasal crackles and pitting oedema to the knees. Her regular medications include Ramipril and Bisoprolol at target doses. Her blood pressure is 120/70 mmHg and renal function is stable. What is the most appropriate next step in management?