report in this issue the experienceover several years with second and thirdpercutaneous mitral balloon valvotomy proce-dures. The report is remarkable because the populationrequired to derive a meaningful experience from patientsundergoing repeated procedures must be large. Theseauthors draw from almost 1500 percutaneous balloonmitral valvotomy (PBMV) procedures, of which 90patients ultimately underwent second and/or thirddilatations.The results are surprising in one important respect.Patients who underwent repeated procedures wereyounger as a group than those who had only a singleprocedure. The authors attribute this to the greaterlikelihood of repeated episodes of active rheumaticdisease in this younger group and this highlights theimportance of remembering to administer rheumaticfever prophylaxis to younger patients undergoing PBMVprocedures