一项研究表明，脑钠肽（BNP）水平接近正常能从
限制型心肌病中区分出
缩窄性心包炎，限制性心肌病的BNP水平是增高的。“现在医生有了一种可以帮助他们发现缩窄性心包炎病人的血液检查”，美国伊利诺州洛约拉（Loyola）大学医学中心的利亚（FerdinandS.Leya）告诉路透社记者，“当病人有心衰的迹象且BNP正常时，就是缩窄性的”。
利亚和同事在11名行血液动力学评估的病人身上评估了血浆BNP水平区别缩窄性心包炎和限制型心肌病的效果和可靠性。他们在5月17日《美国
心脏病学会杂志》（JournaloftheAmericanCollegeofCardiology）上报告，6名病人被发现有缩窄性心包炎，5人为限制性心肌病。这些病人的心内压均增高，而收缩压几乎相等。BNP的正常范围是0～100pg/mL，但缩窄性心包炎病人（平均128.0pg/mL，中位数143pg/mL）显著低于限制型心肌病人（平均825.8pg/mL；中位数，756pg/mL）。
右心房压、肺动脉压、左心房压、肺毛细血管楔压和左心室舒张末压两组没有显著不同。
鉴别这两种疾病对治疗颇为重要。“缩窄性的可以通过剥去心脏的纤维性
疤痕的手术来有效治疗”，利亚说，“而限制性的，如淀粉样变，需要内科治疗”。“还需要更多研究来确定BNP水平诊断缩窄性和局限性的准确性”，他补充。
BNPLevelsDifferentiateConstrictivePericarditisFromRestrictiveCardiomyopathy
NEWYORK（ReutersHealth）May19-Near-normalbrainnatriureticpeptide（BNP）levelsdistinguishconstrictivepericarditisfromrestrictivecardiomyopathy,inwhichBNPlevelsareelevated,astudyshows."Doctorsnowhaveanofficebloodtestwhichwillhelpthemidentifypericardialconstrictionintheirpatient,"Dr.FerdinandS.LeyatoldReutersHealth."WhenthepatienthassignsofheartfailureandnormalBNP,suchapatienthasconstriction."
Dr.LeyaandcolleaguesfromLoyolaUniversityMedicalCenterinMaywood,Illinois,evaluatedtheefficacyandreliabilityofplasmaBNPlevelsindifferentiatingconstrictivepericarditisandrestrictivecardiomyopathyin11patientsundergoinghemodynamicassessment.
Sixpatientswerefoundtohaveconstrictivepericarditis,andfivewerefoundtohaverestrictivecardiomyopathy,theauthorsreportintheMay17thexpresspublicationofJournaloftheAmericanCollegeofCardiology.All11patientshadelevatedintracardiacpressureswithnearequalizationofalldiastolicpressures.
BNPlevels,whichnormallyrangefrom0to100pg/mL,weresignificantlyloweramongpatientswithconstrictivepericarditis（mean,128.0pg/mL;median,143pg/mL）thanamongpatientswithrestrictivecardiomyopathy（mean,825.8pg/mL;median,756pg/mL）,thereportindicates.
Rightatrialpressure,pulmonaryarterypressure,leftatrialpressure,pulmonarycapillarywedgepressure,andleftventricularend-diastolicpressuredidnotdiffersignificantlybetweenthetwogroups,theresearchersnote.
Distinguishingbetweenthetwoconditionsistherapeuticallyimportant."Constrictioncanbeeffectivelytreatedwithsurgery,bystrippingthefibroticscarawayfromtheheart,"Dr.Leyasaid."Restriction,i.e.,amyloidosis,requiresmedicaltreatment."
"MoreresearchisneededtodeterminetheaccuracyoftheBNPlevelindiagnosingconstrictionversusrestriction,"Dr.Leyaadded.
JAmCollCardiol.Availableonline13April2005.
Theefficacyofbrainnatriureticpeptidelevelsindifferentiatingconstrictivepericarditisfromrestrictivecardiomyopathy.
FerdinandS.LeyaMD,DineshArabMD,DominiqueJoyalMD,KrystynaM.ShiouraPhD,BruceE.LewisMD,LowellH.SteenMDandLeslieChoMD.
DivisionofCardiology,SectionofInterventionalCardiology,SectionofHeartTransplant,LoyolaUniversityMedicalCenter,Maywood,Illinois.
Objectives:Wesoughttodeterminetheusefulnessofbrainnatriureticpeptide（BNP）measurementstodifferentiateconstrictivepericarditis（CP）fromrestrictivecardiomyopathy（RCMP）.Background:ThedifferentiationofCPfromRCMPmaybeclinicallydifficultandoftenrequireshemodynamicassessment.Nolaboratorymarkerhasbeenshowntodifferentiatethetwoconditions.Methods:WemeasuredBNPlevelsin11patientssuspectedofhavingeitherCPorRCMP.AllpatientshadhemodynamicassessmentthedayofBNPmeasurements.Results:SixpatientshadCPandfivepatientshadRCMPbasedonestablishedhemodynamiccriteria.BothCPandRCMPpatientshadsimilarelevationinintracardiacpressures.Despitesimilarpressures,themeanplasmaBNPlevelsweresignificantlyhigherinRCMPcomparedtoCP（825.8±172.2pg/mlvs.128.0±52.7pg/ml,p<0.001,respectively）.Conclusions:TheBNPlevelsaresignificantlyelevatedinRCMPcomparedtoCPpatients;BNPmayprovetobeausefulnoninvasivemarkerforthedifferentiationofthetwoconditions.
