1、Dilated CardiomyopathyDCMGU JunDept.of Cardiovascular Medicine Case A 36 year old man comes to your office complaining of three months of progressive fatigue and dyspnea on exertion.Several times in the past month he has awakened from sleep with severe breathlessness and felt a need to sit up in ord
2、er to breath.He denies any chest pain.He has no past medical history of heart disease,hypertension or diabetes.His family history is negative for heart disease.He does not smoke and drinks alcohol only rarely.He takes no medications.Physical ExaminationBP 105/70mmHg,P 98 regularLungs:rales.Heart:Enl
3、arged heart border.S1 diminished intensity,S2 normal,S3 is present.2/6 systolic murmur at the apex.Abdomen:Liver is enlarged and slightly tender to pressure.Extremities:Mild edema of both feet.Dilated Cardiomyopathy,DCMnHeart muscle disordernEnlarged left ventricle or both ventriclesnImpaired systol
4、ic pump functionnOften with manifestation of heart failure or arrhythmiaEpidemiologynAnnual incidence:5-10 patients per millionnMale-female ratio:2.5:1nAverage age of incidence:40nHigher incidence in the developing countriesnAnnual mortality rate:25%-45%EtiologynNot clearnFamilial/genetic(20%)nViral
5、 infectious agents and autoimmunenAcute viral myocarditisdilated cardiomyopathynChronic hormonal disorders nUse of certain substances,especially alcohol,cocaine,antidepressants,and chemotherapy drugs PathologynGross examination：Thinned ventricular walls Enlarged ventricles Fibrin and scar Mural thro
6、mbusNormal valves and coronary arteriesDCM NormalnMicroscopic examination:Myocardial cell may be hypertrophy,denaturation,fibrosis or necrosis.PathologyPump less Heart failureMyocardial changes involve conduction systemArrhythmiaMural thrombus fall offEmbolismClinical ManifestationnSymptoms：No sympt
7、om in the early stage Fatigue,dyspnea,orthopnea Anorexia,edema Palpitation,arrhythmia(Af,VT)Embolism(brain,lung,lower extremity)Sudden death(VT,embolism,bradycardia)Clinical ManifestationnSigns：Cardiac dullness extends to left and downwards Rales,pleural effusion Jugular venous distention,hepatomega
8、ly,edema Gallop rhythm,S3,S4Systolic murmur over the apex area(mitral insufficiency)Accessory ExaminationnChest X-ray Enlargement of the heart Signs of pulmonary congestion Accessory ExaminationnECG Atrial fibrillation Conduction block ST-T changes Low-voltage QRS Pathologic Q wave Ventricular prema
9、ture or tachycardiaAccessory ExaminationAccessory ExaminationnEchocardiography Dilated left ventricle or both ventricles Relative mitral/tricuspid insufficiency due to dilated left/right ventricle Ventricular walls not thick Poorly contractile left ventricle EF 50%Accessory ExaminationnCoronary angi
10、ography:Usually normalnCardiac biopsy:Fibrosis or myocardial celluar hypertrophy,denaturation or necrosisExclude other heart diseases Dilated heartArrhythmiaHeart failure Echo:dilated&poorly contractile ventricle Coronary/Rheu-matic/Hypertensive heart diseaseDiagnosisSpecific cardiomyopathy EXCLUDED
11、iagnosisDCMIschemic cardiomyopathy ICMAgeHistoryOften in middleage，40 years oldMyocarditis,No history of angina Risk factors of CHD,history of angina or myocardial infarctionDifferential diagnosis DCM ICMEchoOften four chambers dilated，the weak movement of whole heart,mural thrombus in some patients
12、Often only left ventricle dilated,segmental movement abnormality，ventricular aneurysm in some patients Angio-graphyNormalMultivessel diseaseDifferential diagnosisTreatmentnGeneral treatmentDecreased activity and bed restSalt restrictionStop alcoholNutritional supportTreatmentnTreatment of heart fail
13、ureDigitalisDiureticsVasodilatorsACEI(angiotensin converting enzyme inhibitors)ARB(angiotensin receptor blockers)TreatmentnAntiarrhythmic treatmentBeta blockers(start with low-dose,increase dose gradually)Amiodarone Pacemaker implantationICD(implantable cardioverter defibrillator)TreatmentnCRT(Cardiac Resynchronization Therapy)nSurgery:heart transplantationQuestionsnWhat are echocardiographic findings in DCM?nHow to distinguish between DCM and ICM?nHow to treat DCM?
