Case 143 Medical history An 11-year-old male patient was admitted in the emergency room presenting with fatigue, fever and severe dyspnea, especially when lying on his back, for the past 15 days. He also complained of pain on the right knee in the past couple days. Patient has a history of pharyngitis on the last month (antistreptolysin O < 200 U). On the physical exam, presented with tachypnea, fever, S3 on cardiac auscultation and a systolic murmur in the mitral area, grade III/VI (Levine Grading Scale). Patient was taken to the Pediatric Cardiology service, where a doppler echocardiogram was performed. Image 1: Doppler echocardiogramImage 2: Doppler echocardiogram Question: Based on clinical history and the images presented, the most likely diagnosis is: Endocarditis Myocarditis Rheumatic fever Kawasaki disease Time is Up! Time's up