A 28-year-old woman presents to the outpatient clinic with a 6-month history of exertional dyspnea and palpitations. On examination, a high-pitched, holosystolic murmur is heard at the apex, radiating to the axilla. The murmur increases with handgrip maneuver. Echocardiography confirms mitral regurgitation (MR) with an ejection fraction of 62%. She is currently asymptomatic at rest. What is the most appropriate next step in management?