One day after admission to the hospital for an inferior ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention, a 55-year-old man develops shortness of breath. He has type 2 diabetes mellitus. Current medications include enoxaparin, insulin, lisinopril, metoprolol, and atorvastatin. His pulse is 92/min and blood pressure is 115/75 mmHg. Fine crackles are heard at both lung bases. Heart sounds are normal. A grade 2/6 holosystolic murmur is heard best over the apex, radiating to the axilla. At admission, his lungs were clear, and no murmurs were heard. Which of the following is the most appropriate management for the valvular pathology?