Hypoplastic right-heart syndrome (HRHS) is a rare, cyanotic congenital heart malformation (see this term) caused by underdevelopment of the right-sided heart ...xShareShareRarediseasesSearchClinicalSignsandSymptomsClassificationsGenesDisabilityEncyclopaediaforpatientsEncyclopaediaforprofessionalsEmergencyguidelinesSources/proceduresHomepageRarediseasesSearchSearchforararedisease*(*)mandatoryfieldSearchDiseasenameORPHAcodeOMIMICD-10GenenameorsymbolOthersearchoption(s)AlphabeticallistSuggestanupdate(*)Requiredfields.Youare(*)Choose:HealthprofessionalPatient/Family/AssociationBiopharmaceuticalindustryScientistStudentOtherIfyouhaveselectedthe“Other”category,pleasespecifywhichtypeofuseryouare:*Emailaddress:*Topicofyourcomment*EpidemiologydataSummaryandrelatedtextsRelatedgenesClinicalsignsNomenclatureand/orcodingYourmessage*(3000charactersremaining)AttentionOnlycommentsseekingtoimprovethequalityandaccuracyofinformationontheOrphanetwebsiteareaccepted.Forallothercomments,pleasesendyourremarksviacontactus.OnlycommentswritteninEnglishcanbeprocessed.Orphanetdoesn'tprovidepersonalisedanswers.TogetintouchwiththeOrphanetteam,pleasecontactInformationprovidedinyourcontribution(includingyouremailaddress)willbestockedin.CSVfilesthatwillbesentasanemailtoOrphanet'steams.Theseemailsmightbeconservedintheteams'mailboxes,inourbackofficeserversbutwillnotberegisteredinourdatabases(formoreinformationseeoursectionGeneralDataProtectionRegulationanddataprivacy(GDPR)andConfidentiality).CheckthisboxifyouwishtoreceiveacopyofyourmessagePleasereproducethetextbelow:*HypoplasticrightheartsyndromeDiseasedefinitionHypoplasticright-heartsyndrome(HRHS)isarare,cyanoticcongenitalheartmalformation(seethisterm)causedbyunderdevelopmentoftheright-sidedheartstructures(tricuspidvalve,RV,pulmonaryvalve,andpulmonaryartery)commonlyassociatedwithanatrialseptaldefect,ostiumsecundumtype(seethisterm).Pulmonarybloodflowisdiminishedandright-to-leftshuntingoccursattheatriallevel,leadingtodyspnea,fatigue,atrialarrhythmias,ri