A 55-year-old woman is evaluated in the cardiology clinic for follow-up of heart failure with reduced ejection fraction. She reports persistent fatigue and dyspnea when walking up a single flight of stairs. Her current medications include maximum tolerated doses of sacubitril-valsartan, bisoprolol, and dapagliflozin. Blood pressure is 118/76 mmHg and heart rate is 68/min. A recent echocardiogram showed a left ventricular ejection fraction of 30%. The physician decides to add spironolactone to her regimen to improve her long-term outcomes. Which of the following diagnostic tests must be obtained 1 to 2 weeks after initiating this medication? (Select all that apply)
- Serum potassiumCevap
- Serum creatinineCevap
- CSerum magnesium
- DProthrombin time
- ETransthoracic echocardiography
Cevap
Serum potassium and serum creatinine
The correct options are serum potassium and serum creatinine. Spironolactone is a mineralocorticoid receptor antagonist (MRA) that serves as a critical component of guideline-directed medical therapy for heart failure with reduced ejection fraction. By blocking aldosterone at the distal convoluted tubule and collecting duct, it promotes sodium excretion and potassium retention. Because this patient is already taking an angiotensin receptor-neprilysin inhibitor (sacubitril-valsartan), which also decreases aldosterone secretion and promotes potassium retention, she is at a significantly elevated risk for hyperkalemia. Furthermore, MRAs can cause acute renal impairment. Therefore, clinical guidelines strictly mandate checking both serum potassium and renal function (serum creatinine) 1 to 2 weeks after the initiation or dose escalation of an MRA.
Adım Adım Çözüm
Anahtar Kavram
Initiation of a mineralocorticoid receptor antagonist (like spironolactone) requires close monitoring of serum potassium and renal function (creatinine) within 1 to 2 weeks, especially in patients concurrently taking other RAAS inhibitors.