简介:HeartfailureisthemostcommoncauseofhospitalizationintheUnitedStates.Justastheprevalenceofheartfailurehasincreased,thenumberofdiseasesidentifiedthatresultintheheartfailuresyndromehasescalated.Certaincardiomyopathiesthathavepreviouslybeenregardedasveryrarearebeingrecognizedwithincreasingfrequency,becauseofimprovedimagingtechniquesandanincreasedunderstandingofthepathophysiologicmechanismsthatresultinthesediseases.ImprovedechocardiographictechniquesandmethodssuchasspectralDopplerand3Dimagerendering,alongwiththeuseofadvanceddiagnostictoolssuchascardiacCTangiographyandcardiacmagneticresonanceimagingarenowcommon.Theseadvancedimagingmethodshaveledtoanincreasedappreciationofthefrequencyofdiseasessuchasisolatedleftventricularnoncompactionandcardiacamyloidosis.Leftventricularnoncompaction,oncethoughttooccurinroughlyoneinonemillionpatients,mayactuallybeseeninfewerthanonein1000patients.Cardiacamyloidosis,inthesenileform,mayexistin80%of80-year-oldpatients,althoughtheincidenceofclinicalsymptomsisless.Asthegeneticalterationsthatcontributetothesediseasesarefurtherelucidated,improveddiagnosisandabetterunderstandingoftheprognosisoftheseuncommoncardiomyopathieswillfollow.