心肌疾病（英文）课件

1、 Cardiomyopathy and myocarditisTang QizhuTel:88041911-6604 Email:qizhutRenmin Hospital of Wuhan UniversityDifinitionCardiomyopathy is a serious disease in which the heart muscle becomes inflamed and doesnt work as well as it shouldIt can be classified as primary or secondary. Primary cardiomyopathy

2、cant be attributed to a specific cause, such as high blood pressure, heart valve disease, artery diseases or congenital heart defects. Secondary cardiomyopathy is due to specific causesClasification(1995 WHO/ISFC)There are fourmain types:Dilated cardiomyopathyHypertrophic cardiomyopathyRestrictive c

3、ardiomyopathyArrhythmogenic right ventricular dysplasiaDilated cardiomyopathy This type of cardiomyopathy is characterized by a dilatation and impaired contraction of the left or both ventricles ImportancesThe incidence and prevalence of cardiomyopathy appears to be increasing. The reported incidenc

4、e is 0.013-0.084% Cardiomyopathy is an important cause of morbidity and mortality among the worlds aging population Sex: men/women is 2.5/1 Age: All age groups are affected. However, studies suggest that 50% of patients with new onset of disease are younger than 2 yearsCAUSES Cardiomyopathies have m

5、any causes, including nutritional deficiencies, deposits in the heart muscle associated with medical conditions, anemia, stress, viral infections, alcoholism, coronary artery disease, and othersThere is no identifiable cause, although it is suspected to be an end stage of myocarditis SYMPTOMS Sympto

6、ms often develop gradually and usually include symptoms of right heart failure and/or left heart failureBecause the body compensates for dilated cardiomyopathy, the disease may have no symptoms initially. As the condition worsens, the heart may perform normally when a person is resting, but may caus

7、e symptoms during periods of exercise or psychological stressNeck and LungsJugular venous distention (as an estimate of central venous pressure)Hepatojugular refluxLarge cv wave (observed with tricuspid regurgitation)Crackles (pulmonary rales)Signs of pleural effusion may be notedInspection and palp

8、ationPalpate for heaves, shifted point of maximal impulse, and cardiomegaly (broad and displaced point of maximal impulse, right ventricular heave).The normal apical impulse should be approximately the size of a quarter and should be located in one (fourth or fifth) intercostal space. The apical imp

9、ulse is normally within 10 cm of the midsternal line AuscultationMurmurs (with appropriate maneuvers),tachycardia, S2 at the base (paradoxical splitting, prominent P2), S3, and S4 may be notedAn irregularly irregular rhythm (atrial fibrillation) may be notedGallops are almost always present in perso

10、ns with DCMDoppler Echo Marked dilation of the left ventricle with global hypokinesia is the hallmark of the disease. Left ventricular ejection fraction 50%. Left ventricular walls are thin and areas of dyskinesis may be observed. The left atrium is also dilated. varying degrees of mitral regurgitat

11、ion ElectrocardiogramECG changes are usually nonspecificLow voltage complexes Presence of Q waves and inversion of T waves in leads I, II, aVL, and V4 through V6 (anterolateral infarction pattern) Significant arrhythmia Myocardial biopsy The number of biopsy specimens collected should be limited to

12、the minimum required (usually 4-8) Myocyte hypertrophy and fibrosis without lymphocytic infiltrate TREATMENTS Hospitalization may be required of patients when symptoms of dilated cardiomyopathy are severe. Treatment for dilated cardiomyopathy is focused on relief of symptoms, just as is for other ty

13、pes of cardiomyopathy, and is essentially the same as the treatment of heart failure Surgical Care A heart transplant may be considered if heart function is very poorDiet and others A low-salt diet may be recommended to patients and fluid intake may be restricted in some cases. Physical activity may

14、 be restricted as symptoms progress Smoking and alcohol cessation recommendations may be given, because these habits make symptom of dilated cardiomyopathy worse COMPLICATIONSCongestive heart failureCardiac arrhythmias, including lethal arrhythmiasPulmonary (lung) edemaTotal failure of the heart to

15、function (circulatory collapse)Side effects of medications, including low blood pressure (hypotension), light headedness, fainting, lupus reaction, headache, GI upset, and digitalis toxicityHYPERTROPHIC CARDIOMYOPATHYHypertrophic cardiomyopathy is a primary cardiac disease characterized by an inappr

16、opriate myocardial hypertrophy, which occurs in the absence of an obvious hemodynamic load such as aortic stenosis or systemic hypertension HISTORY AND OTHER NAMESHypertrophic Cardiomyopathy was first recognised in the late 1950s. The condition has been known by a number of names including Hypertrop

17、hic Obstructive Cardiomyopathy (HOCM), Idiopathic Hypertrophic Sub-aortic Stenosis (IHSS) and Muscular Sub-aortic Stenosis. The general term Hypertrophic Cardiomyopathy (HCM) is now most widely used THE CAUSEThe cause of Hypertrophic Cardiomyopathy is not yet known. In the majority of cases the cond

18、ition is inherited. In others there is either no evidence of inheritance or there is insufficient information about the individuals family to assess inheritance. In affected families the condition usually passes from one generation to the next and generations are not skipped A Family TreeNEW DISCOVE

19、RIES Recently research has identified abnormalities in at least 6 related genes that are important in the development of heart muscle cells. In approximately 50-60% of families, affected individuals are found to have a mutation in the gene for myosin, troponin T, alpha tropomyosin, cardiac myosin bi

20、nding protein-C, or the essential and regulatory light chains. These are important proteins for the contraction of the heart pathologyan excessive thickening of the muscle. Abnormal myocardial fiber arrangement which interferes with the proper diastolic sequence of relaxation. Abnormal myocardial ca

21、lcium ion handling resulting in high cellular calcium ion concentration in the region of myofibrillar contractile proteins and delayed re-uptake of calcium ion by the sarcoplasmic reticulum resulting in prolonged relaxation. Ischemia. Myocardial fibrosisLEFT VENTRICULAR OUTFLOW TRACT (LVOT) OBSTRUCT

22、ION Approximately 25% of patients with hypertrophic cardiomyopathy manifest variable degree of LVOT obstruction. In some, the obstruction or gradient is absent at rest but this can be provoked by exercise or other physiologic or pharmacologic means mechanism of LVOT obstruction Asymmetric Septal Hyp

23、ertrophy mechanism of LVOT obstruction Asymmetric Septal Hypertrophy with ObstructionThe mechanism of LVOT obstructionThe thick upper septum protrudes in the LVOT reducing the orifice size. Blood flowing through this narrowed LVOT causes a Venturi (suction) effect which draws the anterior leaflet of

24、 the mitral valve towards the septum, further reducing the LVOT orifice size. Simultaneously, as a result of systolic anterior movement of the mitral valve (SAM), there is functional mitral regurgitationsymptom dyspnea :Shortness of breath Exercise capacity may be limited by breathlessness and fatig

25、ue Chest pain pain may occur at rest or during sleep and may persist PalpitationSyncopy/dizziness Sudden deathPHYSICAL EXAMINATIONThe systolic murmur is characteristically crescendo-decrescendo and starts a little after the onset of S1. It is best heard at the left lower sternal border and radiates

26、to the base, but unlike systolic murmur of valvular aortic stenosis, it does not radiate to the carotids. murmurThe intensity of the murmur can be varied by various physiologic and pharmacologic interventions. Tthe murmur (and gradient) can be intensified by decreasing preload (decrease venous retur

27、n) by abrupt assumption of upright posture or by Valsalvas maneuver. The murmur intensity can be diminished by increasing afterload (squatting), or by increasing preload (leg raising in supine position) The murmur of mitral regurgitation is prominent in the apical region and shows the same direction

28、al changes in response to the interventions noted aboveElectrocardiogram or ECGMain features include left ventricular hypertrophy (LVH) pattern and the presence of prominent Q waves which resemble Q waves of myocardial infarction (pseudo-infarction pattern). Ambulatory electrocardiogram may reveal a

29、trial and ventricular arrhythmias including non-sustained ventricular tachycardia (NSVT) Echocardiogram or ECHOinclude hypertrophic walls, ASH, and septal wall to posterior wall ratio of 1.3:1. In patients with HOCM, there is presence of SAM. Left ventricular chamber is normal or small; left atrium

30、may be enlarged. Color Doppler studies provide additional hemodynamic information Cardiac Catheterisationshows a gradient between the main left ventricular chamber and the subaortic chamber proximal to the obstruction. This pull back tracing differentiates obstructive hypertrophic cardiomyopathy fro

31、m aortic stenosis Genetic testingGenetic testing may play an important role in helping doctors rule out other diagnoses. For example, in patients who have a small increase in wall thickness (like trained athletes with ventricular hypertrophy), and some patients with constant high blood pressure who

32、are thought to have HCMTREATMENT Drug TreatmentDrug treatment or medication is primarily given when a person has some or all of the symptoms described earlier Alcohol Septal Ablation A catheterization is performed, alcohol is injected into the septum through a small coronary artery. This causes a co

33、ntrolled myocardial infarction Pacemaker dual chambered pacing would relieve obstruction, eliminate most symptoms and thin the walls of the heart Surgeryre moving a small amount of muscle from the ventricular wall Drug TreatmentBeta-Blockers These drugs reduce heart rate, decrease myocardial contrac

34、tility, prolong diastolic filling time and possess anti-arrhythmic properties especially against exercise- induced arrhythmias Calcium Antagonists Anti-Arrhythmic DrugsAnticoagulantsDiureticsAntibioticsDual Chamber PacemakerIt is believed that pacemaker therapy alters the sequence of contraction whi

35、ch reduces LVOT gradient and improves symptoms Long term benefits, however, are questionable Restrictive cardiomyopathyIt is a disorder of the heart muscle in which the walls of the ventricles become stiff, but not necessarily thickened, such that they resist normal filling with blood. There is no c

36、ure. Treatment aims to ameliorate symptoms caused by the backup of blood into the lungs and veins of the neck and liver SymptomsPatients with RCM present with signs and/or symptoms of heart failure such as fatigue, shortness of breath, tissue swelling (oedema) and abdominal enlargement Up to a third

37、 of patients may present with an embolic complication. Abnormal heart rhythms and palpitations are common whatever the underlying cause of the disease diagnosisThe diagnosis of RCM is usually based a physical examination, an electrocardiogram (ECG) and an echocardiogram. Magnetic resonance imaging (

38、MRI) can provide additional information about the structure of the heart. In some patients a precise diagnosis may require catheterisation of the heart to measure pressures and to perform a biopsy of the heart muscle (removal and microscopic examination of a specimen), which may enable the doctor to

39、 identify the infiltrating substance TreatmentAs the onset of symptoms in RCM is often very insidious, the diagnosis of RCM may be made late in the course of the disease. There is no specific treatment for RCM, and the aims of medical therapy are to improve symptoms of heart failure, treat cardiac r

40、hythm disturbance and to prevent thromboembolism. Pacemakers are indicated for patients with slow heart rates or heart block Arrhythmogenic right ventricular dysplasiaARVD is a rare type of cardiomyopathy in which the muscle tissue in the lower-right chamber of the heart (right ventricle) dies. The

41、dead muscle tissue is replaced by fatPatients can develop dangerous arrhythmias or even go into cardiac arrest, particularly when under physical or emotional stress. Studies have shown that ARVD is a significant cause of sudden cardiac death among young athletes Names Arrhythmogenic Right Ventricula

42、r Cardiomyopathy (ARVC) Even though this disease has been recognised only recently, These are not formal guidelines for assessment or treatment Muscle cells become disorganised and are replaced by fibrous and fatty tissue Patchy involvement of the right ventricle may lead to one or more sites of abnormal electrical activity SYMPTOMS of ARVCPalpitationlight-headednessfatigueblackout or collapse or syncopesymptoms of heart failureRHYTHM DISTURBANCESVentricular ectopics (VE/VPB/VPC)Ventricular tachycardia (VT)Ventricular fibri