cardiomyopathies
TRANSCRIPT
Cardiomyopathies
` 2006 AHA defined cardiomyopathies as “a heterogeneous group of diseases of the myocardium associated with mechanical &/or electrical dysfunction that usually (but not invariably) exhibit inappropriate ventricular hypertrophy or dilatation and are due to a variety of causes that frequently are genetic.”
FACTS: Cardiomyopathy is the 2nd most common cause of sudden death
Prognosis for Cardiomyopathy is very poor
** Undiagnosed until in advanced stages **
Most cardiac disease is secondary to some other condition (e.g., coronary atherosclerosis, hypertension, or valvular heart disease). However, there are some that are attributable to intrinsic myocardial dysfunction. Such myocardial diseases are termed cardiomyopathies ( heart muscle diseases).
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They are a diverse group that includes inflammatory disorders (myocarditis), immunologic diseases (e.g., sarcoidosis), systemic metabolic disorders (e.g., hemochromatosis), muscular dystrophies, and genetic disorders of cardiac muscle cells. In many cases, cardiomyopathies are of unknown etiology (termed idiopathic); however, several previously "idiopathic" cardiomyopathies have been shown to be caused by specific genetic abnormalities in cardiac energy metabolism or structural and contractile proteins.
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Dilated Cardiomyopathy(DCM)
DCM is most common of all CMs(60%)
Dilated cardiomyopathy (DCM) is characterized by progressive cardiac dilation and contractile (systolic) dysfunction. It is sometimes called congestive cardiomyopathy. Approximately 25% to 50% of DCM cases have a familial (genetic) basis. Others result from a variety of acquired myocardial insults including toxic exposures (e.g., chronic alcoholism), myocarditis, and pregnancy . In some patients, the cause of DCM is unknown. Such cases are appropriately called idiopathic dilated cardiomyopathy. Many in this category are likely to be of genetic origin. Regardless of the cause, all share a similar clinicopathologic picture.
Aetiology
Idiopathic (IDC)30% Myocarditis (9%) Viral / Bacterial Infection Ischemic (7%)Genetic disorders 50%(AD)HypertensionHyperthyroidismValvular Heart DiseaseChemotherapyPeripartum CMPCardiotoxic Effects of Drugs or alcohol
Morphologically
The heart in DCM is characteristically enlarged (two to three times its normal weight) and flabby, with dilation of all chambers.
Because of the wall thinning that accompanies dilation, the ventricular thickness may be less than, equal to normal. Mural thrombi are common and may be a source of thromboemboli.
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By definition there is no primary valve pathology; consequently, any valvular insufficiency is a secondary consequence of ventricular chamber dilation. The coronary arteries are usually free of atherosclerotic stenosis. Enlargement of RV & LV cavities without an increase in ventricular septal or free wall thickness → spherical shape & dilatation of heart → Displacement of papillary muscles → Regurgitant lesions despite valve leaflets being normal
Pathophysiology:
Microscopically – fibrosis & scarring
Systolic Dysfunction>>> Diastolic dysfunction
STROKE VOLUME is initially maintained by ↑↑ EDV
With disease progression→Marked LV dilatation with normal or thin wall →↑ Wall stress + Valvular Regurgitation →Overt Circulatory Failure .
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Clinical Features
Symptoms: GRADUAL , MIDDLE AGE, MIMIKING URTI The fundamental defect in DCM is ineffective contraction. Hence in end-stage DCM, the cardiac ejection fraction is typically less than 25%.Typically pts c/o months of fatigue, weakness, reduced exercise tolerance Symptomatic HF (syncope, dyspnea, volume overload)
LVF- Dyspnea, PND, orthopnea, cough, frothy sputum, palpitation
RVF-Odema, abdominal swelling,constipation, RT hypochondrial pain Some patients are asymptomaticMay also present as a Stroke, Arrythmia or Sudden Death. Fifty percent of patients die within 2 years, and only 25% survive longer than 5 years
Physical Signs( signs of heart failure)Tachycardia , pulsus alternansJugular venous distensionPulse pressure is narrowVariable degrees of cardiac enlargementDisplace apical impulse
3rd or 4th heart sound are common (with the bell)MR=blowing scratchy systolicMitral/ tricuspid regurgitation may occurlung--Diminished breath sounds with effusions Rales if in failureSummary==== symptoms and signs of heart failure
Diagnosis:
CXR- Cardiomegaly , Pulmonary venous congestion ,pleural effusion
ECG- Normal or low QRS voltage , abnormal axis, non specific ST seg abnormalities, LV hypertrophy, conduction defects, Non sustained
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Ventricular tachycardia/Sinus tachycardia/atrial fibrillation, Left atrial abnormality, LBBB
2D Echo
Chamber size - Wall thickness/shape( Eccentric hypertrophy/ Usually thin)
Clot formation Ejection Fraction -Normal 55-65%//Mild Dysfunction 41-55%Moderate Dysfunction -----------26-40% Severe Dysfunction----------------<26%
Coronary Angiography- age >40-usually normal coronaries -coronary vasodilatation is impaired by ↑ LV filling pressures-distinguishes b/w Ischemic & Idiopathic DCM
Endomyocardial Biopsyrarely valuable to identify the aetiology
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Management
Aim of treatment-Manage the symptoms -Reduce the progression of disease-Prevent Complications
salt restriction of a 2-g Na+ (5g NaCl) diet
fluid restriction for significant low Na+
Mainstay of Therapy Vasodilators + Digoxin + Diuretics + BB(CARDIOSELECTIVE)
Reduce preload Reduce afterload_ Diuretics Arterial Vasodilators _ Venous Vasodilators ACE Inhibitors_ ACE Inhibitors
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_ Aldosterone antagonists
Increase Contractility_ Decrease afterload_ Digoxin
Vasodilators (afterload reducing drugs)
ACE Inhibitors -Indicated for all patients- Reduce symptoms & improve effort tolerance- Suppress ventricular remodelling & endothelial dysfunction-Reduce CV mortality
SpironolactoneUsed along with ACE Inhibitors has shown to reduce mortality by 30% in a large double blind randomized trial
Digoxinclinically beneficial as reaffirmed by two large trials in adults
β Blockers- carvedilol They provide symptomatic improvement and substantial reduction in sudden death in NYHA class II & III HF pts
Amiodarone-High grade ventricular arrhythmias (Sustained VT or VF) are common in DCM→↑ risk of SCD-Preferred anti arrhythmic agent as it has least negative inotropic effect & proarrhythmogenic potential -Implantable Defibrillators are used for refractory arrhythmias.
Anticoagulants-Indicated for pts with moderate ventricular dilatation+mod-severe systolic dysfunction-H/O stroke , AF or evidence of Intracardiac thrombus
Hydralazine / nitrate combination
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anticoagulation for EF <30%, history of thromboemoli, presence of mural thrombi
intravenous dopamine, dobutamine and/or phosphodiesterase inhibitors
Pts refractory to Pharmacological therapy for CHF
Dual Chamber Pacing
Cardiomyoplasty
LV Assist Devicesimproved pts sufficiently to avoid transplant or enable later transplant
Cardiac Transplantationhas substantially prolonged survival in DCM pts with 5 yr survival rate of 78%.
Hypertrophic Cardiomyopathy
Hypertrophic cardiomyopathy (HCM) (also known as idiopathic hypertrophic subaortic stenosis) is characterized by myocardial hypertrophy, abnormal diastolic filling, and-in a third of cases-ventricular outflow obstruction. The obstruction, in some cases, is dynamic, caused by the anterior leaflet of the mitral valve. The heart is thick-walled, heavy, and hyper contracting. Systolic function is usually preserved in HCM, but the myocardium does not relax and therefore shows primary diastolic dysfunction.
Most common cause of sudden death in young athletes.
Characterized by in appropriate and elaborate LV hypertrophy with misalignment of the myocardial fibres.
Hypertrophy may be generalized or confined largely to interventricular septum
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Heart failure may develop because stiff non-compliant ventricles impede systolic filling and decreased cardiac output
Septal hypertrophy may cause dynamic LV outflow obstruction. Mitral regurgitation occur due to abnormal systolic anterior mitral valve leaflet.
REMMEBER:
Primary genetic cardiomyopathy and left ventricle disease.Effects men and women equallyHypertrophy of myocardial muscle mass Cause - transmitted genetically(autosomal dominant)Disarray of cardiac myofibrils with hypertrophy of myocytesCells take on a variety of shapes Myocardial scarring and fibrosis occurs
Pathophysiology
Condition is genetic disorder with Autosomal Dominant transmission.
Due to single point mutation in one of the genes that encode sarcomeric contractile proteins.
Morphology :
The essential gross feature of HCM is massive myocardial hypertrophy without ventricular dilation .The classic pattern of HCM involves disproportionate thickening of the ventricular septum relative to the left
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ventricle free wall (so-called asymmetrical septal hypertrophy); nevertheless, in about 10% of cases there is concentric hypertrophy. On longitudinal sectioning, the ventricular cavity loses its usual round-to-ovoid shape and is compressed into a "banana-like" configuration .Often present is an endocardial plaque in the left ventricular outflow tract, as well as a thickening of the anterior mitral leaflet. Both findings reflect contact of the anterior mitral leaflet with the septum during ventricular systole and correlate with functional left ventricular outflow tract obstruction.
Pathophysiology( post graduate)
1. Subaortic Obstruction2. Diastolic Dysfunction3. Myocardial Ischemia4. Mitral Regurgitation5. Arrythmias
A. Subaortic Obstruction1. Cause -Assymetrical Septal Myocardial Hypertrophy .2. Subaortic Obstruction
Effect-Systolic anterior motion(SAM) of AML → accentuating obstructionMechanism of SAMThickened IVS→Restricted LVOT → ejection of blood at a higher velocity closer to the AML → Drawing of AML closure towards the hypertrophied septum due to the venturi effect → Dynamic LVOT obstruction
Factors aggregating SAM and cause dynamic obstruction(30-50%):
↑ Contractility ↓ Afterload (Aortic outflow resistance) ↓ Preload (End diastolic volume)
Therapeutically Myocardial depression, Vasoconstriction & Volume overloading should minimize obstruction & augment forward flow
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B. Diastolic Dysfunction
STIFF LEFT VENTRICLE/IMPAIRED RELAXATION/PASSIVE FILLING
ATRIAL KICK (S4) IS ESSENTIAL TO MAINTAIN CARDIAC OUT PUT
DECREASE LV CAVITY= DIASTOLIC DYSFUNCTION= LV FILLING
FILLING PRESSURES & PULMONARY CONGESTION
Compensation for decreased filling -> hyperdynamic systolicDysfunction ------------EF increases to 70-80%
c.Mitral Regurgitation– Hypertrophied papillary muscles– Leaflets become calcified and thick– Atrial dilatation_ Enlargement of mitral valve annulus
D. Myocardial Ischemia
◦ Often occurs with normal coronary arteries.
◦ Postulated mechanisms
Abnormally small coronary arteries as a result of hypertrophy
Inadequate number of capillaries for the degree of LV mass
Early closure of aortic valve with decreased cardiac output Increased myocardial oxygen demand due to :1. Myocardial hypertrophy2. Diastolic dysfunction3. Myocyte disarray4. LVOT obstruction5. Arrhythmia
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Types Hypertrophic Cardiomyopathy
• Asymmetric septal (ASH) - without obstruction• Asymmetric septal (ASH) - with obstruction• Symmetric hypertrophy - concentric• Apical hypertrophy• HCM or HOCM
Signs & SymptomsHCM is characterized by a massively hypertrophied left ventricle with diastolic failure and systolic dysfunction. In addition, roughly 25% of patients have dynamic obstruction to the left ventricular outflow by the anterior leaflet of the mitral valve.
Many asymptomatic for years Incidence of sudden death often first presentation Identified during screening of relative of patient with HCM Symptoms related to severity of diastolic dysfunction or
mitral regurgitation.
1. Dyspnea on exertion (90%)/activity intolerance-LVF , HF ,ISCHEMIA
2. Angina on effort (70-80%)
3. Syncope on effort (20%)-LVOT
4. Palpitations
5. Sudden cardiac death
1. Ventricular wall mass > 30 mm increased risk2. More common in patients under 40
3. Normally occurs during strenuous activity
SIGNS(( MR+ AS))
Pulse- Irregular Pulse (with Atrial-fibrillation)
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Bisferiens Carotid Pulse (HOCM) – Brisk initial upstroke/ jerky pulse
– Collapse of pulse then secondary rise – Must differentiate from AS – delayed upstroke
Apex beat- forceful and brisk/LV heave /Double impulse at apex S4 MR murmur-Pansystolic murmur
Systolic murmur with obstructive disease process Sign of LV outflow obstruction- Mid systolic, best heard along left sternal boarder, usually does not radiate, crescendo-decrescendo, harsh or rough
HOCM murmur louder during Valsalva’s maneuver Decreases venous return to the heart
– Decreased preload _ _ Decreased left ventricular filling _ _obstruction
Any factor that decreases venous return to the heart increases the murmur in HOCM
– Squatting increases venous return – Standing decreases venous return
Aortic stenosis murmur becomes quieter during Valsalva’s maneuver
Diagnosis:
.2/3 of patients have family H/O, the rest have sporadic mutations (de novo) HIGH INDEX OF SUSPECION IN YOUNG MALE WITH SYNCOPY.
ECG-It is abnormal in 75 to 95% of patients, ↑ QRS voltage, ST-T changes, Axis
deviation, LV Hypertrophy +strain pattern, p wave abnormalities, Negative TWaves in V3-V5 (apical HCM),Abnormal Q waves may reflect septal hypertrophy
CXR-Lt atrial enlargement or normal
Echo Wall thickness -LV size, Hyperdynamic LV function, Atrial size MV leaflets, LV outflow obstruction
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Management
Goals– Relief of symptoms- Relax the ventricle
Slow the Heart Rate
– Use Negative Inotropes
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– Preventing complications– Preventing or reducing risk of sudden death– No evidence to support treatment of nonsymptomatic patients
DRUGS
B-blocker and rate-limiting calcium antagonists (eg verapamil)
Most patients are improved by therapy that promotes ventricular relaxation.
β Blockers- mainstay of therapy Relieves symptoms of exercise intolerance & dyspnoea associated with CHF by- negative inotropic effect -HR reduction , lower myocardial O2 demand - longer diastolic filling times , improve filling of LV
CCB-Verapamil is indicated if β Blockers not tolerated or ineffective-It improves diastolic function & ventricular relaxation causing improved filling, decreased obstructive features in 50% pts-CCBs with strong vasodilatory effect are C/I in pts with obstructive symptoms
Cardioversion (ATRIAL-Fib to Sinus) Anticoagulants Amidarone ACE-I AND NGT to be avoided. Diuretic - with caution
SURGERY: Indications1. Subaortic gradients≥ 50mmHg frequently associated with CHF & are refractory to medication2. Marked outflow obstruction3. On maximum medical therapy4. NYHA Class III or IV
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Septal Myotomy +Partial Mymectomy through a transaortic approach relieves the obstruction, reduces the LVOTO gradient, SAM & MR
MV Replacement or repair at same time (increases operative mortality) Improvement noted immediately and last 20-30 years May need pacer due to development of LBBB. Complications –CHB or septal perforation (0-2%) Mortality rate-1to 3% Percutaneous Alcohol SeptalAblation
Not appropriate if MVR needed, Better for patients > 55Catheter in septal perforatorEthyl alcohol injected -MI occurs-Enlarged septum eventually shrinks
Ablation of AV Node (HOCM),Dual Chamber Pacemaker (HOCM)Heart Transplant
COMPLICATION:1. Atrial fibrillation, VT , V.fibrillation. 2. Mural thrombus formation3. IE of the mitral valve4. CHF5. Sudden death. Prognosis
Adults - 2-3% SCD per y Adolescents - 4-6% SCD per year
MARKERS OF INCREASED RISK1. Prior cardiac arrest or spontaneous sustained VT.2. Family history of premature HCM death3. Syncope or near syncope (exertional or recurrent)4. Multiple and repetitive burst of NSVT5. Hypotensive response of BP to exercise6. LVH greater than 30 mm(septum)7. Myocardial ischemia (with angina)
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Restrictive CM
WHO in 1995 defined RCM as restrictive filling & reduced diastolic volume of either or both ventricles with normal or near normal systolic function & wall thickness.
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Restrictive cardiomyopathy is characterized by a primary decrease in ventricular compliance, resulting in impaired ventricular filling during diastole ( the wall is stiffer). The contractile (systolic) function of the left ventricle is usually unaffected. Thus, the functional state can be confused with that of constrictive pericarditis or hypertrophic cardiomyopathy. Restrictive cardiomyopathy can be idiopathic or associated with systemic diseases that also happen to affect the myocardium .
Least common form of Cardiomyopathy 5% of 1ry heart muscle Disease.
Ventricular filling is impaired because ventricles are stiff. Lead to high atrial pressure with atrial hypertrophy, dilatation and later
atrial fibrillation. Amyloidosis is the most common cause
Pathophysiology: Ventricular chamber has limited ability to expand during filling (diastolic dysfunction)- Filling Impairment- Rate of LV filling is slow Decreased volume available to eject- Elevated LV filling pressure Pressure Overload -------- Often elevated LV EF.
stroke volume & cardiac output
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1. volume and pressure in atria(INCREASE)2.Dilated atrium due to increase volume & pressure3.Increase volume & pressure in pulmonary system4.Heart failure symptoms
3 problems:1. Stiffness of the ventricle2. Ventricular Filling Reduced3. The rigidity of the myocardium causes failure to completely contract
during systole-------------((End-result is decreased CO))----------
CAUSES Primary---idiopathic• MYOCARDIAL
1. Noninfiltrative Idiopathic, Scleroderma2. InfiltrativeAmyloid 90% north AMERICA ,Sarcoidosis ,Gaucher disease, Radiation carditis , Hurler disease
3. Storage DiseaseHemochromatosis, Fabry disease, Glycogen storage
• ENDOMYOCARDIAL Endomyocardial fibrosis, Hyperesinophilic syndrome, Carcinoid metastatic malignancies, radiation, anthracycline
Signs & Symptoms:HEART FAILURE IS THE END RESULT OF CARDIOMYOPATHY.Fatigue, weakness ,SyncopePalpitations with arrhythmiasDyspnea, Orthopnea EdemaChest PainSIGNS –
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Pale/ cool-------Peripheral pulse decreased, Pulsus paradoxusJVP-prominent x and y descents Kussmaul’s sign-↑ JVP during inspiration Murmur of Mitral Regurgitation-----Systolic Murmur, 5th ICS MCLM.R.- Dilation of atrium , Papillary muscle dysfunction, Fibrosis of leafletsS4----------Left Lateral Position, Bell of Stethoscope
Diagnosis: Diagnosis is difficult Rule Out Other Causes of Diastolic Dysfunction
a. Aortic Stenosisb. Hypertrophic Cardiomyopathyc. Hypertensive Cardiovascular Disease
Differentiate from Constrictive Pericarditis.
Clinical Features Constrictive Pericarditis
Restrictive Cardiomyopathy
History Prior history of pericarditis orcondition that causespericardial disease
History of systemic disease (e.g..Amyloidosis, Hemochromatosis)
Heart Sounds Pericardial knock, high frequency sound
Presence of loud diastolic fillingsound S3, low frequency sound
Murmurs No murmurs
Murmurs of mitral and tricuspidinsufficiencyArrhythmias
Heart PressuresL & R filling pressures up andequal(Elevated JVP)
L sided filling pressures > R sidedfilling pressures
Require complex Doppler echocardiography
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CXR- pulmonary congestion, small heart size, Dilated atrium ,Congestion if in HF Calcified pericardium can be seen inconstrictive pericarditis.
ECG- Low QRS voltage, No-specific ST-T wave Changes, P wave
abnormalities,Arrhythmias,Conduction abnormalities, BBBs, low voltage, QR or QS complexes, An abnormal heart rhythm is customary
• Echo-Doppler abnormal mitral inflow pattern prominent E wave (rapid diastolic filling) reduced deceleration time ( LA pressure)
Impaired ventricular relaxation & abnormal Compliance causes rapid filling in early diastole & impeded filling during rest of diastole Characteristic Ventricular diastolic waveform of Dip & Plateau (Square root sign) -RA pressure waveform-M or W shaped due to rapid y descent
Pressure in the ventricle rises precipitously in response to small volume Both ventricles appear thick(Increased in infiltrative disorders )with small
cavities in contrast to corresponding dilated atria Lt sided Pulmonary venous pressure >Rt sided venous pressure by 5mmHg PASP↑↑ upto 50mmHg Speckled appearance on myocardium with amyloidosis
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Cardiac Catheratization Full cath not necessary -Hemodynamic measurements valuable
_ Elevated LVEDP_ Elevated PAOP_ Elevated RA Pressures_ Elevated pulmonary pressures
CT and MRI and endomyocardial biopsy may be done.Endomyocardial BiopsySeptal wall of RV, Multiple sitesEssential for diagnosis of RCM
Exclusion “Guidelines• LV end-diastolic dimensions ³ 7 cm• Myocardial wall thickness ³ 1.7 cm• LV end-diastolic volume ³ 150 mL/m2• LV ejection fraction < 20%
TREATMENTThere is no cure for the disease. Similar to most types of cardiomyopathies there are ways to reduce symptoms and prevention.The purpose OF medical treatment is to alleviate the problems of heart rate and prevent blood clots.Transplantation is the best treatment.
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IdiopathicDiuretics-To relieve congestionB-blockers, Amiodarne, CCBs- Control of HR vasodilators may decrease filling pressureLong term anticoagulation-MR,TR,LA LARGE,AF, FIBROSISCCBs, ACEI- To enhance myocardial relaxationDual Chamber Pacing- AV blockCardiac Transplantation- Refractory Heart Failure
Amyloidosis- Melphelan, prednisone, H+L transplant Haemochromatosis- Phlebotomy, Desferrioxamine Treat Rhythm
AF Control - Loss of atrial kick, Digoxin cautiously in amyloidosis Conduction abnormalities ---------May require pacemaker
Outcomes_ Poorest mortality of all cardiomyopathies_ 90% mortality rate at 10 years (Kavinsky & Parrillo, 2000)._ Amyloid Heart 80% mortality at 2 years
Arrhythmogenic Right Ventricular Dysplasia Patches of the right ventricular myocardium are replaced with fibrous
and fatty tissue. Inherited as autosomal dominant trait Dominant clinical problems are
ventricular arrhythmia Sudden death Right sided cardiac failure
ECG shows inverted T waves in the right precordial leads. MRI useful diagnostic tool and used to screen 1st degree relatives from
having the same pathology.
Obliterative Cardiomyopathy Involves the endocardium of one or both ventricles and is characterized
by thrombosis and elaborate fibrosis with gradual obliteration of the ventricular cavities.
Mitral and tricuspid valves are regurgitant. Heart failure and pulmonary and systemic embolism are prominent. Associated with eosinophilia
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Eg: eosinophilic leukemia, churg strauss syndrome Mortality is high (50% at 2 years of developing the symptoms) Anticoagulation and antiplatelet therapy is advisable and diuretics may
help symptoms of HF. Surgery valve replacement with decortication of endocardium may be
helpful in certain cases.
Myocarditis
In myocarditis there is inflammation of the myocardium with resulting injury. It is important, however, to emphasize that the presence of inflammation alone is not diagnostic of myocarditis; for example, inflammatory infiltrates can also occur as a secondary response to ischemic injury. In myocarditis, the inflammatory process is the cause of-rather than a response to-myocardial injury.
Lymphocytic myocarditis is most common .If the patient survives the acute phase of myocarditis, the inflammatory lesions either resolve, leaving no residual changes, or heal by progressive fibrosis
Pathogenesis
INFECTIONS Viruses-coxsackie virus, HIV, influenza,ECHO,cytomealovirus
Chlamydiae Psittaci Rickettsiae typhi , typhus fever Bacteria-Diphtheriae, Neisseria meningeocccus,Lyme disease Fungus- Candida Protozoa-Trypanosome (chagas disease), Toxoplasmosis Helminths- Trichinosis
IMMUNE MEDIATED REACTIONS Post viral Post streptococcal-Rheumatic fever Systemic lupus erythematosus Transplant rejection Drug hypersensitivity- methyl dopa, sulphonamides UNKNOWN
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Giant cell myocarditis SarcoidosisClinical Features The clinical spectrum of myocarditis is broad. At one end, the disease is asymptomatic and patients recover without sequelae, and at the other end is the precipitous onset of heart failure or arrhythmias, occasionally with sudden death. Between these extremes are the many forms of presentation, associated with a variety of symptoms (e.g., fatigue, dyspnea, palpitations, pain, and fever). The clinical features of myocarditis can even mimic those of acute MI. Occasionally, over many years, patients can progress from myocarditis to DCM
Diagnosis:Symptoms: non-specificLaboratory Testing: also non-specific
Positive cardiac biomarkers ECG: T wave inversion, ST segment elevation, bundle branch blocks
ECHO Differentiate fulminant from acute myocarditis Detect thrombi, valvular abnormalities, and pericardial involvement
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Rule out other cardiomyopathies (HOCM, Takotsubo)
Cardiac MRI
Non-invasive Visualize entire myocardium Use to guide biopsy Follow disease course and response to therapy
Coronary Angiography Rule out other congenital, rheumatic, or ischemic heart disease Determine need for inotropic or mechanical support based on
hemodynamic parameters Elevated pulmonary artery pressures are independent predictors of
mortalityEndomyocardial Biopsy
Although controversial, still the current gold-standard test for diagnosis 1-6% complication rate Consider when suspicious for:
1. Giant cell myocarditis 2. Hypersensitivity/eosinophilic myocarditis 3. Cardiac involvement in a systemic disease
All other patients, consider only if pt is deteriorating
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Treatment
Circulation: Intra-aortic balloon pump counterpulsation Ventricular assist device Cardiopulmonary assist device
Medical therapy1. ACE-inhibitors2. Beta-blockers
Most therapy used in HF patients appears to benefit those with HF due to myocarditis – with the exception of digoxin
Immunosuppressive therapy- N0 RULE
Intra-aortic balloon pump
Electrocardiographic synchronized phased pulsation
o Inflation with aortic valve closure
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o Deflation just before systole
Reduce systolic arterial pressure (afterload)
o Reduces myocardial oxygen consumption
Augment diastolic arterial pressure
o Enhances coronary blood flow
Mean pressure unchanged
Ventricular-assist device
Centrifugal pump or Archimedes’ screw type
Inflow from LV and outflow into aorta
Has been used as a bridge in myocarditis until recovery or transplant
Disadvantages:
1. Surgical implantation
2. infection
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3. thrombosis
4. hemolysis
“Loose” rule of third’s…
1/3: recover
1/3: residual ventricular dysfunction
1/3: transplantation or death
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Most common cause is viruses (adeno and coxsackie)
Highly variable clinical manifestations
Cardiac MRI looks promising for diagnosis
Biopsy is the gold standard but should be pursued in only select patients
Aggressive, supportive care is the first line therapy because of high incidence of recovery
Immunosuppressive therapy does not affect mortality
Supportive therapy is mainstay therapy
Most medical therapies for HF seem to benefit myocarditis patients with the exception of digoxin
Immunosuppressive therapy does not seem to play a role in survival
BIOPSY
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