Mitral regurgitation (MR), whether primary or secondary, stems from functional or anatomical impairment of components of the mitral apparatus resulting in abnormal blood flow to the left atrium during systole. A common complication is bilateral pulmonary edema (PE), which, in rare instances, may be unilateral and easily misdiagnosed. This case presents an elderly male with unilateral lung infiltrates and progressive exertional dyspnea with the failed treatment of pneumonia. Additional workup, including a transesophageal echocardiogram (TEE), showed severe eccentric MR. He underwent mitral valve (MV) replacement with significant improvement in symptoms.