Disease of myocardium

1. Disease of myocardiumDisease of myocardium
2 categories2 categories
1.1. Primary or non specific idiopathic cardiomyopathyPrimary or non specific idiopathic cardiomyopathy
2.2. Specific heart muscle diseaseSpecific heart muscle disease
a)a) MyocarditisMyocarditis
b)b) Heart muscle disease in other associationHeart muscle disease in other association
 Toxic e.g. alcoholToxic e.g. alcohol
 Metabolic – hypokaelaemia, hyperkalaemia, hyperthyroidism,Metabolic – hypokaelaemia, hyperkalaemia, hyperthyroidism,
hypothyroidismhypothyroidism

2. MyocarditisMyocarditis
Inflammation of myocardium having leukocyte infiltration & degenerationInflammation of myocardium having leukocyte infiltration & degeneration
or non-ischaemic necrosis of myocytesor non-ischaemic necrosis of myocytes
EtiologyEtiology
1. Infective1. Infective
 Viral – Coxsackie A, Influenza, Entero, HIV, Adeno, CMVViral – Coxsackie A, Influenza, Entero, HIV, Adeno, CMV
 Chlamydia and RickettsiaChlamydia and Rickettsia
 Bacteria – diphtheria, Neisseria, BorreliaBacteria – diphtheria, Neisseria, Borrelia
 Fungal & Protozoa – Trypanosoma, Toxoplasma, TrichinellaFungal & Protozoa – Trypanosoma, Toxoplasma, Trichinella
2. Hypersensitivity2. Hypersensitivity
 SLE, RHD, graft rejectionSLE, RHD, graft rejection
 Drugs: penicillinDrugs: penicillin
3. Idiopathic3. Idiopathic
 Giant cell myocarditisGiant cell myocarditis

3. Myocarditis MorphologyMyocarditis Morphology
GrossGross
 Dilated, flabby heart, pale patches with hemorrhage giving mottledDilated, flabby heart, pale patches with hemorrhage giving mottled
appearance, abscess if bacterialappearance, abscess if bacterial
 All 4 chambers may show dilatationsAll 4 chambers may show dilatations
Dilated, globoid heart in myocarditis

4. MicroscopicMicroscopic
 Interstitial inflammatory infiltrate with myocyte necrosis, fibrosis, viralInterstitial inflammatory infiltrate with myocyte necrosis, fibrosis, viral
inclusion bodiesinclusion bodies
 Mononuclear cells – idiopathic or viralMononuclear cells – idiopathic or viral
 Neutrophils – bacterialNeutrophils – bacterial
 Eosinophils –hypersensitivity or protozoaEosinophils –hypersensitivity or protozoa
bacterial myocarditis with intralesional
bacteria
viral myocarditis with lymphocyte
infiltration

5. Primary cardiomyopathyPrimary cardiomyopathy
3 patterns3 patterns
 Dilated (congestive) cardiomyopathy.Dilated (congestive) cardiomyopathy.
 Hypertrophic cardiomyopathyHypertrophic cardiomyopathy
 Restrictive or obliterative cardiomyopathyRestrictive or obliterative cardiomyopathy

6. Dilated CardiomyopathyDilated Cardiomyopathy
 Heart (especially the left ventricle) is enlarged and the pumpingHeart (especially the left ventricle) is enlarged and the pumping
function is diminishedfunction is diminished
 Associated with hypertrophy, dilatation and systolic dysfunction ofAssociated with hypertrophy, dilatation and systolic dysfunction of
heartheart
 Gross – dilatation,Gross – dilatation,

7. Hypertrophic Obstructive Cardiomyopathy( HOCM)/Hypertrophic Obstructive Cardiomyopathy( HOCM)/
idiopathic hypertrophic subaortic stenosis( IHSS)idiopathic hypertrophic subaortic stenosis( IHSS)
 Heart muscle is thickened, which causes diastolic dysfunctionHeart muscle is thickened, which causes diastolic dysfunction
 And LA dilationAnd LA dilation

8. Restrictive CardiomyopathyRestrictive Cardiomyopathy
 uncommon cardiomyopathyuncommon cardiomyopathy
 Walls of the ventricles are stiff, but may not be thickened, and resistWalls of the ventricles are stiff, but may not be thickened, and resist
the normal filling of the heart with blood.the normal filling of the heart with blood.
 Atrial dilataion due to inadequate ventricular fillingAtrial dilataion due to inadequate ventricular filling
Endomyocardial fibrosis of a ventricular
wall. When extensive, this would cause
restrictive heart failure too.

9. Write short notes on myocarditisWrite short notes on myocarditis
Write short notes on pericarditisWrite short notes on pericarditis

10. Write short notes on myocarditisWrite short notes on myocarditis
Write short notes on pericarditisWrite short notes on pericarditis