<prompt> Straight back syndrome is associated with?Mitral valve ProlapseAnkylosing spondylitisOsteopetrosisCor-triatriatum  <response>: Straight back syndrome: Loss of thoracic kyphosis antero-posterior diameter of chest is relatively lesser, so place available for hea is also less. Hea is sandwiched bw thoracic veebrae, sternum and rib cage. Causes Mitral valve Prolapse Mid Systolic click Ankylosing spondylitis - AR condition 