Balloon atrial septostomy.
D006346:Heart Septum / Q000601:surgery*; D006801:Humans; D008722:Methods; D008943:Mitral Valve / Q000002:abnormalities; D011664:Pulmonary Valve / Q000002:abnormalities; D014188:Transposition of Great Vessels / Q000401:mortality / Q000601:surgery*; D014261:Tricuspid Valve / Q000002:abnormalities