The The Pathology of Pathology of Myocardial Myocardial DiseasesDiseases

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(1) (1) CCardiomyopathyardiomyopathy– Defined as “heart muscle disease of Defined as “heart muscle disease of

unknown cause,” generally referred to as unknown cause,” generally referred to as primary or idiopathic cardiomyopathy,primary or idiopathic cardiomyopathy,

(2) (2) SSpecific heart muscle disease pecific heart muscle disease – defined as “heart muscle disease of defined as “heart muscle disease of

known cause or associated with disorders known cause or associated with disorders of other systems.of other systems.

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The clinical picture is largely The clinical picture is largely determined by one of the determined by one of the following three clinical, following three clinical, functional, pathologic patterns, functional, pathologic patterns, each of which can have either a each of which can have either a known or an unknown causeknown or an unknown cause::

Dilated CardiomyopathyDilated Cardiomyopathy (90%)(90%)Hypertrophic CardiomyopathyHypertrophic CardiomyopathyRestrictive CardiomyopathyRestrictive Cardiomyopathy

CCardiomyopathardiomyopathiesies

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Etiology of the DCMEtiology of the DCM : :– 1. Primary (Idiopathic) (30%) DCM1. Primary (Idiopathic) (30%) DCM– 2. Secondary DCM2. Secondary DCM

Dilated Cardiomyopathy Dilated Cardiomyopathy (DCM)(DCM)

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1. Primary (1. Primary (IdiopathicIdiopathic)) dilated dilated cardiomyopathycardiomyopathy

Characterized by the gradual development of cardiac Characterized by the gradual development of cardiac failure associated with four-chamber failure associated with four-chamber hypertrophyhypertrophy and and dilatationdilatation of the heart of unknown cause. of the heart of unknown cause.

FFamilial occurrence amilial occurrence ((approximately 20% of casesapproximately 20% of cases))– aautosomal dominant, autosomal recessive, and X-linked utosomal dominant, autosomal recessive, and X-linked

inheritanceinheritance

Genetic syndromesGenetic syndromes:: – Friedreich's ataxiaFriedreich's ataxia– Duchenne's-Becker's muscular dystrophyDuchenne's-Becker's muscular dystrophy

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Pathophysiology Pathophysiology

Apoptosis, or programmed cell death, has been Apoptosis, or programmed cell death, has been reported in clinical and experimental dilated reported in clinical and experimental dilated cardiomyopathy, which is characterized bycardiomyopathy, which is characterized by– depressed systolic function or systolic pump failure depressed systolic function or systolic pump failure – cardiomegalycardiomegaly– ventricular dilatationventricular dilatation

Reduced left ventricular contractile force leads Reduced left ventricular contractile force leads to decreased cardiac output, resulting in to decreased cardiac output, resulting in increased residual volumes in end-systole and increased residual volumes in end-systole and end-diastole. end-diastole.

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UUsually affects those 20 to 60 years oldsually affects those 20 to 60 years old

SSlowly developlowly developss

Fifty percent of patients die within 2 yearsFifty percent of patients die within 2 years – only 25% of patients survive longer than 5 yearsonly 25% of patients survive longer than 5 years

Death is usually attributable to Death is usually attributable to – progressive cardiac failure progressive cardiac failure and/and/or or – arrhythmiaarrhythmia

Embolism from dislodgEmbolism from dislodgeement of an ment of an intracardiac thrombus may occurintracardiac thrombus may occur

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Secondary dilated cardiomyopathiesSecondary dilated cardiomyopathies– AlcoholismAlcoholism– Chemicals&DrugsChemicals&Drugs

Heavy metalsHeavy metalsEmetineEmetineDoxorubicinDoxorubicinCocaineCocaineMethamphetamineMethamphetamineCobaltCobalt

– High output states High output states Anemia Anemia Thyrotoxicosis Thyrotoxicosis PregnancyPregnancy

– HIV and other infectionsHIV and other infectionsViral Viral endocarditis/myocarditisendocarditis/myocarditisParasitesParasitesProtozoaProtozoaChagas disease (most Chagas disease (most common cause in parts of common cause in parts of South America)South America)

– Collagen vascular diseaseCollagen vascular disease– Glycogen storage diseaseGlycogen storage disease– Thiamine deficiency and Thiamine deficiency and

zinc deficiencyzinc deficiency– HypophosphatemiaHypophosphatemia– AmyloidosisAmyloidosis– Neuromuscular disordersNeuromuscular disorders

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PathologyPathologyThe heart is usually heavyThe heart is usually heavy– Weighing two to three times normal, Weighing two to three times normal, – FlabbyFlabby ( (usually with dilatation of all chambersusually with dilatation of all chambers))

Nevertheless, because of the wall thinning that Nevertheless, because of the wall thinning that accompanies dilatation, the ventricular wall accompanies dilatation, the ventricular wall thickness may be less than, equal to, or more thickness may be less than, equal to, or more than normal. than normal. Mural thrombi are commonMural thrombi are common– particularly near the apex of the left and right particularly near the apex of the left and right

ventricles and in the atriaventricles and in the atria thromboembolithromboembolismsm

MMitral regurgitation, when present, is primarily itral regurgitation, when present, is primarily a result of left ventricular chamber dilatation a result of left ventricular chamber dilatation (functional mitral regurgitation). (functional mitral regurgitation).

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The left ventricle often has patchy The left ventricle often has patchy myocardial (mostly subendocardial) myocardial (mostly subendocardial) fibrous scarsfibrous scars

The sizes of individual muscle cells vary; The sizes of individual muscle cells vary;

The nuclei are usually enlarged The nuclei are usually enlarged throughout, indicating hypertrophy. throughout, indicating hypertrophy.

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ComplicationsComplications– Heart failureHeart failure– Volume overloadVolume overload– Pulmonary edemaPulmonary edema– HypoxiaHypoxia– Cardiogenic shockCardiogenic shock– DeathDeath

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Arrhythmogenic Right VentricularArrhythmogenic Right Ventricular

CardiomyopathyCardiomyopathy ((Right ventricular Right ventricular Dysplasia)Dysplasia)

FFamilial disorderamilial disorderPProgressive nature of the lesion with apoptosis rogressive nature of the lesion with apoptosis SSudden death in vigorous good healthudden death in vigorous good health– right-sided and sometimes left-sided heart failure right-sided and sometimes left-sided heart failure – rhythm disturbancesrhythm disturbances ( (particularly ventricular tachycardiaparticularly ventricular tachycardia))

Morphology Morphology – the right ventricular wall is severely thinned, the right ventricular wall is severely thinned,

extensive fatty infiltrationextensive fatty infiltrationloss of myocytes loss of myocytes interstitial fibrosisinterstitial fibrosis

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Hypertrophic CardiomyopathyHypertrophic Cardiomyopathy (HCM)(HCM)

Hypertrophic cardiomyopathy is also known by Hypertrophic cardiomyopathy is also known by such terms as such terms as

Synonyms:Synonyms: – idiopathic septal hypertrophyidiopathic septal hypertrophy– asymmetric septal hypertrophyasymmetric septal hypertrophy– Les Aspin's diseaseLes Aspin's disease– Reggie Lewis's diseaseReggie Lewis's disease– muscle-bound heartmuscle-bound heart

A A genetic basisgenetic basis in many cases in many cases

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It is characterized by a heavy muscular It is characterized by a heavy muscular hypercontracting heart, in striking contrast hypercontracting heart, in striking contrast to the flabby, hypocontracting heart of to the flabby, hypocontracting heart of ddilated CMilated CM. .

In contrast to the hypertrophy induced by In contrast to the hypertrophy induced by the increased workload of valvular, the increased workload of valvular, hypertensive, ischemic, and congenital hypertensive, ischemic, and congenital heart diseases, that observed in heart diseases, that observed in HHypertrophic ypertrophic CM develops progressively in CM develops progressively in the absence of an identifiable extrinsic the absence of an identifiable extrinsic inciting stressinciting stress..

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End-stage heart failure can be End-stage heart failure can be accompanied by dilatation. accompanied by dilatation.

The major problems in HCM areThe major problems in HCM are::– atrial fibrillation with mural thrombus formation, atrial fibrillation with mural thrombus formation, – embolization from the mural thrombi, embolization from the mural thrombi, – infective endocarditisinfective endocarditis on the mitral valve, on the mitral valve, – intractable cardiac failure, intractable cardiac failure, – sudden deathsudden death ( (most common cause of death most common cause of death

and particularly likely in young males with and particularly likely in young males with familial HCM or with a family history of sudden familial HCM or with a family history of sudden deathdeath)). .

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Morphological findingsMorphological findings

The essential anatomic feature of HCM is The essential anatomic feature of HCM is massivemassive myocardial hypertrophymyocardial hypertrophy. .

The classic pattern is said to be The classic pattern is said to be disproportionatedisproportionate thickening of the ventricular thickening of the ventricular septum septum as compared with the free wall of the as compared with the free wall of the left ventricle (with a ratio greater than 1.3), left ventricle (with a ratio greater than 1.3), frequently termedfrequently termed asymmetric septal asymmetric septal hypertrophy. hypertrophy.

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Restrictive cardiomyopathy can be Restrictive cardiomyopathy can be idiopathic or secondary to a heart muscle idiopathic or secondary to a heart muscle disease that manifests as restrictive disease that manifests as restrictive physiology. physiology.

The common hemodynamic disturbance is The common hemodynamic disturbance is impairment of ventricular fillingimpairment of ventricular filling due to the due to the thickening and increased rigiditythickening and increased rigidity of the of the endocardium and myocardium secondary endocardium and myocardium secondary to infiltration by to infiltration by amyloid amyloid or byor by fibrosis. fibrosis.

RestrictiveRestrictive Cardiomyopathy Cardiomyopathy (RCM)(RCM)

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Systolic function remains normal or near Systolic function remains normal or near normal until late stages. normal until late stages.

Most older people get some amyloid in Most older people get some amyloid in their atria and aortas. their atria and aortas.

If amyloid involves the myocardium If amyloid involves the myocardium extensively, the extensively, the muscles cannot contractmuscles cannot contract. .

This is the usual cause of "This is the usual cause of "restrictive restrictive cardiomyopathycardiomyopathy". ".

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Etiology: Etiology: – Idiopathic restrictive cardiomyopathyIdiopathic restrictive cardiomyopathy

Loeffler eosinophilic endomyocardial diseaseLoeffler eosinophilic endomyocardial disease

– Secondary restrictive cardiomyopathySecondary restrictive cardiomyopathyHemochromatosisHemochromatosis

AmyloidosisAmyloidosis

SarcoidosisSarcoidosis

Progressive systemic sclerosis (scleroderma)Progressive systemic sclerosis (scleroderma)

Carcinoid heart diseaseCarcinoid heart disease

Glycogen storage disease of the heartGlycogen storage disease of the heart

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MORPHOLOGY: MORPHOLOGY: – the ventricles are of approximately normal the ventricles are of approximately normal

size or slightly enlargedsize or slightly enlarged– the cavities are not dilatedthe cavities are not dilated– the myocardium is firm the myocardium is firm – bbiatrial dilatation iatrial dilatation ((commoncommon))

Microscopically there is Microscopically there is patchy or diffuse patchy or diffuse interstitial fibrosisinterstitial fibrosis/amyloid/amyloid..

Specific Heart Muscle Specific Heart Muscle DiseaseDisease

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Cardiac infectionsCardiac infectionsVirusesViruses– coxsackieviruscoxsackievirus– ECHOECHO– influenzainfluenza– HIVHIV– CMVCMV

Chlamydia Chlamydia (C.psitacci)(C.psitacci)

RickettsiaRickettsiaBacteriaBacteria– CorynebacteriumCorynebacterium– NeisseriaNeisseria– BorreliaBorrelia

Fungi Fungi (Candida)(Candida)

Protozoa Protozoa – TrypanosomaTrypanosoma– ToxoplasmaToxoplasma

HelminthHelminth (Trichinosis) (Trichinosis)

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Toxic substancesToxic substances

AlcoholAlcohol

CobaltCobalt

CathecolaminesCathecolamines

COCO

LithiumLithium

HydrocarbonsHydrocarbons

ArsenicArsenic

Cancer chemotherapyCancer chemotherapy

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Metabolic causesMetabolic causes

HyperthyroidismHyperthyroidism

HypothyroidismHypothyroidism

HypokalemiaHypokalemia

HyperkalemiaHyperkalemia

Hypoproteniamia,Hypoproteniamia,

HypovitaminosisHypovitaminosis(thiamin(thiamine)e)

HemochromatosisHemochromatosis

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NeuromuscularNeuromuscular

diseasedisease

Stroge disordersStroge disorders

Friedreichs ataxiaFriedreichs ataxia

Muscular dystrophiaMuscular dystrophia

Congenital atrophiesCongenital atrophies

Hunter-Hurler syndromeHunter-Hurler syndrome

Glycogen storage Glycogen storage diseasedisease

AmyloidosisAmyloidosis

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InfiltrativeInfiltrative

diseasesdiseases

Immun-Immun-mediatedmediated

reactionsreactions

LeukemiaLeukemia

CarcinomatosisCarcinomatosis

SarcoidosisSarcoidosis

Radiation-induced fibrosisRadiation-induced fibrosis

MyocarditisMyocarditis

Post-transplant rejectionPost-transplant rejection

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MyocarditisMyocarditis Myocarditis is an uncommon disease that is Myocarditis is an uncommon disease that is characterized by characterized by inflammationinflammation of the heart; of the heart;– leukocytic infiltrate leukocytic infiltrate – resultant nonischemic necrosis resultant nonischemic necrosis – degeneration of myocytesdegeneration of myocytes

Subsequent myocardial destruction often Subsequent myocardial destruction often leads to a dilated cardiomyopathy. leads to a dilated cardiomyopathy. Most cases of well-documented myocarditis Most cases of well-documented myocarditis are are viralviral in origin. in origin.

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Infectious Infectious agentsagents

- VirusesViruses ((Coxsackievirus(B)Coxsackievirus(B), Advenovirus, , Advenovirus, Echovirus, EBV, Hepatitis C, HHV, HIV, CMV, Echovirus, EBV, Hepatitis C, HHV, HIV, CMV, Influenza, Measles, Mumps, Rubella, Varicella)Influenza, Measles, Mumps, Rubella, Varicella)

- ChlamydiaChlamydia (C.psitacci)(C.psitacci)

- RickettsiaRickettsia ( (R. rickettsii, R. tsutsugamushiR. rickettsii, R. tsutsugamushi))

- Bacteria Bacteria (Corynebacterium, Neisseria, Borrelia, (Corynebacterium, Neisseria, Borrelia, Klebsiella, Leprospira, Cocci, Clostridia, Klebsiella, Leprospira, Cocci, Clostridia, Treponema, Brucella, Salmonella)Treponema, Brucella, Salmonella)

- FungiFungi (Candida, Actinomycosis, (Candida, Actinomycosis, Coccidioidomycosis, Histoplasmosis)Coccidioidomycosis, Histoplasmosis)

- Protozoa Protozoa (Trypanosoma cruzi,(Trypanosoma cruzi, toxoplasma, toxoplasma, amebiasis)amebiasis)

- Other parasitesOther parasites ( (Toxocara canis, Toxocara canis, Schistosomiasis, Heterophyiasis, Cysticercosis, Schistosomiasis, Heterophyiasis, Cysticercosis, Echinococci, Visceral larva migrans.Echinococci, Visceral larva migrans.

Etiology of Etiology of MyocarditisMyocarditis

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Immun-mediated Immun-mediated reactionsreactions

Drugs Drugs – Hypersensitivity myocarditis is Hypersensitivity myocarditis is

observed with a variety of observed with a variety of medications (eosinophilic infiltrate medications (eosinophilic infiltrate of the myocardium)of the myocardium)

– A direct cytotoxic effect on the A direct cytotoxic effect on the myocardiummyocardium

- Post-transplant rejectionPost-transplant rejection

- MedicationsMedications- penicillin, ampicillin, penicillin, ampicillin,

hydrochlorothiazide, methyldopa, hydrochlorothiazide, methyldopa, sulfonamidesulfonamide

- lithium, doxorubicin, cocaine, lithium, doxorubicin, cocaine, numerous catecholamines, numerous catecholamines, acetaminophen, acetaminophen, cyclophosphamide, tetracycline, cyclophosphamide, tetracycline, isoniazid, phenytoin, ect. isoniazid, phenytoin, ect.

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ChemicalsChemicals

Systemic diseasesSystemic diseases

Radiation therapyRadiation therapy (dilated cardiomyopathy)(dilated cardiomyopathy)

Lead Lead

Arsenic Arsenic

Carbon monoxideCarbon monoxide

Scorpion envenomationsScorpion envenomations

Autoimmune diseases ( SLE, Autoimmune diseases ( SLE, Scleroderma, Rhematoid arthritis)Scleroderma, Rhematoid arthritis)

SarcoidosisSarcoidosis

Giant cell myocarditisGiant cell myocarditis

SLE SLE

Giant cell arteritisGiant cell arteritis

DermatomyositisDermatomyositis

Ulcerative colitisUlcerative colitis

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It may occur at any ageIt may occur at any age

The The vulnerable vulnerable ones...ones...– infantsinfants– immunosuppressed individuals immunosuppressed individuals – pregnant womenpregnant women

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A Specific type of Myocarditis:A Specific type of Myocarditis: Chagas’ Chagas’ diseasediseaseCaused by Caused by aa protozoa protozoa: : Trypanosoma cruziTrypanosoma cruziAlthough uncommon in the northern Although uncommon in the northern hemisphere, Chagas’ disease affects up to one-hemisphere, Chagas’ disease affects up to one-half of the population in endemic areas of South half of the population in endemic areas of South AmericaAmerica..Myocardial involvement is found in Myocardial involvement is found in approximately approximately 80%80% of infected individuals. of infected individuals.

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TrichinosisTrichinosis

The most common helminthic disease with The most common helminthic disease with associated cardiac involvement. associated cardiac involvement.

Corynebacterium diphtheriaeCorynebacterium diphtheriae

Traditionally considered a myocarditis, injury to Traditionally considered a myocarditis, injury to the myocardium by the potent exotoxin of the the myocardium by the potent exotoxin of the bacterium bacterium Corynebacterium diphtheriaeCorynebacterium diphtheriae is is characterized by patchy myocyte necrosis with characterized by patchy myocyte necrosis with only a sparse lymphocytic infiltrate.only a sparse lymphocytic infiltrate.

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HIV myocarditisHIV myocarditis

Myocarditis occurs in many patients with Myocarditis occurs in many patients with acquired immunodeficiency syndrome acquired immunodeficiency syndrome (AIDS).(AIDS).

Two types have been identified: Two types have been identified: – (1) inflammation and myocyte damage without (1) inflammation and myocyte damage without

a clear etiologic agenta clear etiologic agent– (2) myocarditis caused directly by HIV or by (2) myocarditis caused directly by HIV or by

an opportunistic pathogen an opportunistic pathogen

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MorphologyMorphology During the active phase of myocarditis, the During the active phase of myocarditis, the heart may appear heart may appear normal or enlarged with normal or enlarged with dilatation of either ventricle or all chambersdilatation of either ventricle or all chambers. . The lesions may be The lesions may be diffuse or patchydiffuse or patchy. . The The ventricular myocardiumventricular myocardium is typically is typically flabby and often mottled by either pale foci flabby and often mottled by either pale foci or minute hemorrhagic lesions. or minute hemorrhagic lesions. The The endocardium and valves are endocardium and valves are unaffectedunaffected except that mural thrombi may except that mural thrombi may be present in any chamber.be present in any chamber.

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Microscopic classification:Microscopic classification:NonmyocarditisNonmyocarditisActive myocarditisActive myocarditis– Characterized by abundant inflammatory cells Characterized by abundant inflammatory cells

and myocardial necrosis and myocardial necrosis

Borderline myocarditisBorderline myocarditis– Characterized by an inflammatory response Characterized by an inflammatory response

that is too sparse for this type to be labeled as that is too sparse for this type to be labeled as active myocarditis; degeneration of myocytes active myocarditis; degeneration of myocytes not demonstrated with light microscopy. not demonstrated with light microscopy.

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HHistologistologyyDuring During AActive myocarditisctive myocarditis

Interstitial mononuclear, predominantly Interstitial mononuclear, predominantly lymphocytic inflammatory infiltratelymphocytic inflammatory infiltrate ( (focal focal or patchyor patchy) +) +Focal necrosisFocal necrosis

necrosis and disarrangement of the necrosis and disarrangement of the myocytes are typical and often are seen myocytes are typical and often are seen with coxsackievirus infectionwith coxsackievirus infectionoccasionally with a necrotic myocyteoccasionally with a necrotic myocyte ((often with contraction bands)often with contraction bands)

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TThe histologic pattern of reaction to bacterial or he histologic pattern of reaction to bacterial or fungalfungal invasioninvasion depends on the specific depends on the specific causative organismcausative organism, if present., if present.

Hypersensitivity reactionsHypersensitivity reactions that involve the that involve the myocardium induce interstitial infiltrates that are myocardium induce interstitial infiltrates that are principally perivascular, composed of principally perivascular, composed of lymphocytes, macrophages, and a high lymphocytes, macrophages, and a high proportion of proportion of eosinophils.eosinophils.

In the chronic and healing stagesIn the chronic and healing stages, myocytes are , myocytes are replaced by fibroblasts (scar tissue). replaced by fibroblasts (scar tissue).

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– In In giant cell myocarditisgiant cell myocarditis, giant cells are , giant cells are present in the myocardium with or without present in the myocardium with or without granulomas.granulomas.

Tuberculosis, syphilis, rheumatoid arthritis, Tuberculosis, syphilis, rheumatoid arthritis, rheumatic heart disease, or with fungal or rheumatic heart disease, or with fungal or parasitic infections. parasitic infections.

The characteristic cell probably is histiocytic in The characteristic cell probably is histiocytic in origin and usually is found in nonviral origin and usually is found in nonviral myocarditis. myocarditis.

Similar cells have been noted in patients with Similar cells have been noted in patients with myocarditis associated with drugs such as myocarditis associated with drugs such as phenylbutazonephenylbutazone. .

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– Systemic lupus erythematosusSystemic lupus erythematosus (SLE) may (SLE) may demonstrate demonstrate myocardialmyocardial fibrinoid lesionsfibrinoid lesions found in the connective tissue with an found in the connective tissue with an accompanying cellular reaction. accompanying cellular reaction.

This reaction also may affect the valves, most This reaction also may affect the valves, most notably, the mitral and aortic valves. notably, the mitral and aortic valves.

Libman and SacksLibman and Sacks describe this latter type of describe this latter type of endocarditis. endocarditis.

Although the predominant cardiac manifestation Although the predominant cardiac manifestation of SLE is pericarditis, myocardial involvement of SLE is pericarditis, myocardial involvement with CHF can occurwith CHF can occur

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Viral MyocarditisViral Myocarditis

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Aspergillus MyocarditisAspergillus Myocarditis

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Pyemic MyocarditisPyemic Myocarditis

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Complications: Complications: – Congestive heart failureCongestive heart failure– Pulmonary edemaPulmonary edema– Cardiogenic shockCardiogenic shock– Cardiac failureCardiac failure– Recurrent myositisRecurrent myositis– Dysrhythmia/ArrhythmiaDysrhythmia/Arrhythmia– Thromboembolism.Thromboembolism.

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Secondary cardiomyopathiesSecondary cardiomyopathiesAlcoholAlcoholCChemotherapy (doxo- and daunorubicin; Adriamycin)hemotherapy (doxo- and daunorubicin; Adriamycin)Cathecolamines and PCathecolamines and Pheochromocytomaheochromocytoma ("catecholamine heart", with single-fiber necrosis as in ("catecholamine heart", with single-fiber necrosis as in cocaine heart)cocaine heart)Peripartum cardiomyopathyPeripartum cardiomyopathyAmyloidosisAmyloidosisHemochromatosisHemochromatosisHyper-/hypo- thyroidismHyper-/hypo- thyroidismPompe's glycogenosisPompe's glycogenosisDuchenne's & Friedreich'sDuchenne's & Friedreich's Disease DiseaseEEnd-stage HIV infectionnd-stage HIV infection

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AlcoholAlcoholAlcohol or its metabolites (especially acetaldehyde) Alcohol or its metabolites (especially acetaldehyde) has a direct toxic effect on the myocardiumhas a direct toxic effect on the myocardiumCChronic alcoholism may be associated with hronic alcoholism may be associated with thiamine deficiency, introducing an element of thiamine deficiency, introducing an element of beriberi heart diseasberiberi heart diseasee

Adriamycin and Other DrugsAdriamycin and Other DrugsSome of the Some of the chemotherapeutic agents doxorubicin chemotherapeutic agents doxorubicin ((aadriamycin) and daunorubicin are well recognized driamycin) and daunorubicin are well recognized causes of toxic myocardial injurycauses of toxic myocardial injuryMany other agents, such as lithium, Many other agents, such as lithium, phenothiazines, and cocaine, have been implicated phenothiazines, and cocaine, have been implicated in myocardial injuryin myocardial injuryCocaine also causes catecholamine-induced cell Cocaine also causes catecholamine-induced cell damagedamage

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Peripartum cardiomyopathyPeripartum cardiomyopathy

PPregnancy invokes the possibilities of regnancy invokes the possibilities of – hypertensionhypertension– volume overloadvolume overload– nutritional deficiencynutritional deficiency– other metabolic derangementother metabolic derangement– immunologic reactionimmunologic reaction

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AmyloidosisAmyloidosis

Cardiac amyloidosis may appear along Cardiac amyloidosis may appear along with systemic amyloidosis or may affect with systemic amyloidosis or may affect only the heart, particularly in the aged only the heart, particularly in the aged (senile isolated cardiac amyloidosis)(senile isolated cardiac amyloidosis)

Clinically important amyloid deposits can Clinically important amyloid deposits can occur in the hearts of patients with occur in the hearts of patients with multiple multiple myelomamyeloma

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HHereditary hemochromatosis and ereditary hemochromatosis and hemosiderosishemosiderosis

Most commonly with a dilated patternMost commonly with a dilated patternIron deposition is more prominent in Iron deposition is more prominent in ventricles than atria and in the working ventricles than atria and in the working myocardium than in the conduction myocardium than in the conduction systemsystemMicroscopyMicroscopy– marked accumulation of hemosiderin within marked accumulation of hemosiderin within

cardiac myocytescardiac myocytes ( (intracellularintracellular))– Varying degrees of cellular degeneration Varying degrees of cellular degeneration

and fibrosisand fibrosis

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