简介：ObjectivesPhenotypicoverlapofBrugadasyndromewithtype3longQTsyndromeisobservedinsomecarriersofmutationsintheNachannelSCN5A.Concomitant-Brugadasyndromeand3typelongQTsyndromeassociatedwithsodiumchannelmutationwasreportedbefore,however,nodatashowedconcomitant-BrugadatypeandshortQTintervalelectrocardiogram(ECG)andrevealedtheassociated-genemutation.MethodsThedirectDNAsequencewasconducedtofindthemutation.Themutationwasreproducedinvitrousingsite-directedmutagenesisandcharacterizedusingthepatchclamptechniqueinthewhole-cellconfiguration.ResultsThepatientwiththefamilyhistoryofsuddendeathshowedBrugadaandshortQTintervalECG.SequenceofSCN5Aidentifiedamissensemutation,R689H,previouslyassociatedwithalongQTsyndrome.BiophysicalstudyshowedthattheR689Hfailedtogenerateanycurrentwhenheterolo-gouslyexpressedinHEKcells.ConclusionsOurfindingsindicateforthefirsttimethatcoexisted-BrugadatypeandshortQTintervalECGlinkedtothelossoffunctioninSCN5Amutation.