The nurse is auscultating the heart sounds of a patient with mitral stenosis. The pulse rhythm is weak and irregular. What rhythm does the nurse expect to see on the electrocardiogram (ECG)?
a) Ventricular tachycardia
b) First-degree atrioventricular block
c) Sinus dysrhythmia
d) Atrial fibrillation
Answer: Atrial fibrillation