We report the case of a 39-year-old woman who developed worsening dyspnea and abdominal pain 4 days after subtotal gastroresection. She underwent thoracic computed tomography scan and lung scintigraphy and was diagnosed with pulmonary embolism. Despite the fact that she was feverish, she was treated by the insertion of a vena cava filter and transferred to our Emergency Department. Twelve hours later, a beta-haemolytic Streptococcus agalactiae was reported to be growing in both bottles of blood cultures that had been taken. The patient underwent transthoracic two- and three-dimensional echocardiography, which showed a large pulmonary valve vegetation prolapsing into the main and right pulmonary artery during systole.