心肌病心内科

Dilated CardiomyopathyDCM,GU 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 order 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 Examination,BP 105/70mmHg, P 98 regularLungs: rales.Heart: Enlarged 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, DCM,Definition,Heart muscle disorderEnlarged left ventricle or both ventriclesImpaired systolicpump functionOften with manifestation of heart failure or arrhythmia,Epidemiology,Annual incidence: 5-10 patients per millionMale-female ratio: 2.5 : 1Average age of incidence: 40Higher incidence in the developing countriesAnnual mortality rate: 25%-45%,Etiology,Not clearFamilial/genetic (20%)Viral infectious agents and autoimmuneAcute viralmyocarditis can progress to chronic dilated cardiomyopathyChronic hormonal disorders Use of certain substances, especially alcohol, cocaine, antidepressants, and chemotherapy drugs,Pathology,Gross examination： Thinned ventricular walls Enlarged ventricles Fibrin and scar Mural thrombus Normal valves and coronary arteries,DCM Normal,Microscopic examination: Myocardial cell may be hypertrophy, denaturation, fibrosis or necrosis.,Pathology,Pathophysiology,Pump less blood for the bodys needs,Heart failure,Myocardial changes involve conduction system,Arrhythmia,Mural thrombus fall off,Embolism,Clinical Manifestation,Symptoms： No symptom in the early stage Fatigue, dyspnea, orthopnea Anorexia, edema Palpitation, arrhythmia (Af, VT) Embolism (brain, lung, lower extremity) Sudden death (VT, embolism, bradycardia),Clinical Manifestation,Signs： Cardiac dullness extends to left and downwards Rales, pleural effusion Jugular venous distention, hepatomegaly, edema Gallop rhythm, S3, S4Systolic murmur over the apex area (mitral insufficiency),Accessory Examination,Chest X-ray Enlargement of the heart Signs of pulmonary congestion,Accessory Examination,ECG Atrial fibrillation Conduction block ST-T changes Low-voltage QRS Pathologic Q wave Ventricular premature or tachycardia,Accessory Examination,Accessory Examination,Echocardiography 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 Examination,Coronary angiography: Usually normalCardiac biopsy: Fibrosis or myocardial celluar hypertrophy, denaturation or necrosis,Exclude other heart diseases,Dilated heartArrhythmiaHeart failure,Echo:dilated& poorly contractile ventricle,Coronary/Rheu-matic/Hypertensive heart disease,Diagnosis,Specific cardiomyopathy,EXCLUDE,Diagnosis,DCM,Ischemic cardiomyopathy ICM,Age,History,Often in middleage，40 years old,Myocarditis, No history of angina,Risk factors of CHD, history of angina or myocardial infarction,Differential diagnosis,DCM,ICM,Echo,Often four chambers dilated，the weak movement of whole heart , mural thrombus in some patients,Often only left ventricle dilated, segmental movement abnormality，ventricular aneurysm in some patients,Angio-graphy,Normal,Multivessel disease,Differential diagnosis,Treatment,General treatmentDecreased activity and bed restSalt restrictionStop alcoholNutritional support,Treatment,Treatment of heart failureDigitalisDiureticsVasodilatorsACEI (angiotensin converting enzyme inhibitors )ARB (angiotensinreceptor blockers),Treatment,Antiarrhythmic treatmentBeta blockers (start with low-dose, increase dose gradually)Amiodarone Pacemaker implantationICD (implantable cardiov