pictures: cardiomyopathy Flashcards
Dilated cardiomyopathy definition and pathogensis
- Progressive cardiac dilation and systolic dysfunction, usually with dilated hypertrophy.
- Pathogenesis:
- Thought to be familial in 30-50% of cases (TTN mutations may account for 20% of all cases); usually autosomal dominant.
- Alcohol is strongly linked to DCM
- Myocarditis
- Cardiotoxic drugs/substances: doxorubicin, cobalt, iron overload
Dilated cardiomyopathy
Morphology and Presentation
Dilated cardiomyopathy
- Morphology:
- dilation of all chambers
- mural thrombi are common
- functional regurgitation of valves
- Presentation
- usually manifests between ages 20-50
- progressive CHF → dyspnea, exertional fatigue, ↓ EF arrhythmias
- embolism
Takotsubo cardiomyopathy
- Takotsubo cardiomyopathy
- “Broken heart syndrome”
- Excess catecholamines following extreme emotional or psychological stress
- >90% women, ages 58-75
- Symptoms and signs similar to acute myocardial infarction
- Apical ballooning of the left ventricle with abnormal wall motion and contractile dysfunction
Arrhythmogenic right ventricular cardiomyopathy
- Arrhythmogenic right ventricular cardiomyopathy
- Right ventricular failure and arrhythmias
- Myocardium of the RIGHT ventricular wall replaced by adipose and fibrosis
- Causes ventricular tachycardia and fibrillation, sudden death Familial (usually autosomal dominant)

- Arrhythmogenic right ventricular cardiomyopathy
- Right ventricular failure and arrhythmias
- Myocardium of the right ventricular wall replaced by adipose and fibrosis
- Causes ventricular tachycardia and fibrillation, sudden death Familial (usually autosomal dominant)

- Arrhythmogenic right ventricular cardiomyopathy
- Right ventricular failure and arrhythmias
- Myocardium of the right ventricular wall replaced by adipose and fibrosis
- Causes ventricular tachycardia and fibrillation, sudden death Familial (usually autosomal dominant)

Hypertrophic cardiomyopathy
- A genetic disorder leading to myocardial hypertrophy and diastolic dysfunction, leading to reduced stroke volume and often ventricular outflow obstruction
- Numerous mutations known, involving sarcomeric proteins
- Most commonly β-myosin heavy chain
- Morphology: massive myocardial hypertrophy, often with marked septal hypertrophy. Microscopically, myocyte disarray.
White bits in the ventricular wall indicate interstitial fibrosis/scarring

- Hypertrophic cardiomyopathy: image shows interstitial fibrosis (scarring).
- A genetic disorder leading to myocardial hypertrophy and diastolic dysfunction, leading to reduced stroke volume and often ventricular outflow obstruction
- Numerous mutations known, involving sarcomeric proteins
- Most commonly β-myosin heavy chain
- Morphology: massive myocardial hypertrophy, often with marked septal hypertrophy. Microscopically, myocyte disarray.

Amyloid (restrictive cardiomyopathy)
- Extracellular deposition of proteins which form an insoluble β-pleated sheet.
- May be systemic (myeloma) or restricted to the heart (usually transthyretin)
- Certain mutated versions of transthyretin are more amyloidogenic
- Amyloid can involve different parts of the heart, but when deposits are in the interstitium of the myocardium, a restrictive cardiomyopathy results
- Image shows pale and pink pattern typical for protein deposition- still needs to be proven with congo red stain (the neon green stain)

- Amyloid (restrictive cardiomyopathy): image shows congo red stain, apple green neon shows protein
- Extracellular deposition of proteins which form an insoluble β-pleated sheet.
- May be systemic (myeloma) or restricted to the heart (usually transthyretin)
- Certain mutated versions of transthyretin are more amyloidogenic
- Amyloid can involve different parts of the heart, but when deposits are in the interstitium of the myocardium, a restrictive cardiomyopathy results.
Restrictive cardiomyopathy
- Decreased ventricular compliance (increased stiffness), leading to diastolic dysfunction.
- May be secondary to deposition of material within the wall
- (amyloid), or increased fibrosis (radiation).
- Ventricles are usually of normal size, but both atria can be enlarged.

- Lymphocytic infiltrate, consistent with viral myocarditis
- Myocarditis
- Inflammation of the myocardium, most commonly due to a virus.
- Coxsackie A and B viruses are most common
- Other infectious causes include
- rypanosomes (Chagas disease)
- Various bacteria and fungi
- Noninfectious causes include
- Immune mediated reactions, including RF, SLE, drug hypersensitivity


- Transposition of the great arteries
- Results in two separate circuits, incompatible with life after birth unless a shunt is present for mixing of blood from the two circuits
- Approximately one third have a VSD
- Two thirds have a patent foramen ovale or PDA
- Right ventricle becomes hypertrophic (supports systemic circulation) and the left ventricle atrophies.
- Without surgery, patients will die within a few months

- Tetrology of Fallot (classically R–> L shunting)
- Four cardinal features:
- VSD
- Obstruction of RV outflow tract
- Aorta overrides the VSD
- RV hypertrophy
- Heart is enlarged and “boot shaped” because of the right ventricular hypertrophy
- Clinical severity depends on the degree of subpulmonary stenosis
- Mild stenosis: L to R shunt.
- Classic TOF is R to L shunting with cyanosis
ASD
- Atrial septal defect
- Usually asymptomatic until adulthood
- The left-to-right shunting causes volume overload on the right side, which may lead t
- Pulmonary hypertension
- Right heart failure
- Paradoxical embolization
- May be closed surgically, with normal survival
VSD
Ventricular septal defect (heart becomes “dusky red”)
- Most common form of congenital heart disease
- Effects depend on size, and presence of other heart defects Many small VSDs close spontaneously
- Large VSDs may cause significant shunting, leading to
- Right ventricular hypertrophy
- Pulmonary hypertension, which can ultimately reverse flow through the shunt, leading to cyanosis
Patent ductus arteriosis
- Patent ductus arteriosis
- May fail to close when infants are hypoxic, and/or have defects associated with increased pulmonary vascular pressure (VSD)
- PDA produces a harsh machinery-like murmur Effect is determined by the shunt’s diameter
- Large shunts can increase pulmonary pressure and eventually shunt reversal and cyanosis
- May fail to close when infants are hypoxic, and/or have defects associated with increased pulmonary vascular pressure (VSD)
what are the L–R shunts mentioned in class?
VSDs, ASDs, PDA
what are the R–> L shunts mentioned in class?
w and w/out VSD, TOF ??
in a congenital R–> L shunt compared to a congenital L–> R shunt
Right-to-left shunts. Cyanosis is seen soon postnatally

- Coarctation of the aorta: infantile form
- Narrowing of the aorta, generally seen with a PDA (infantile form), or without a PDA (adult form).
- Degree of narrowing is variable, with variable clinical effect
- Coarctation with PDA manifests at birth: may produce cyanosis in the lower half of the body
- Coarctation without PDA – usually asymptomatic
- Hypertension in upper extremities, hypotension in lower extremities
- Claudication and cold lower extremities
- May eventually see concentric LV hypertrophy

- Coarctation of the aorta: adult form
- Narrowing of the aorta, generally seen with a PDA (infantile form), or without a PDA (adult form).
- Degree of narrowing is variable, with variable clinical effect
- Coarctation with PDA manifests at birth: may produce cyanosis in the lower half of the body
-
Coarctation without PDA – usually asymptomatic
- Hypertension in upper extremities, hypotension in lower extremities
- Claudication and cold lower extremities
- May eventually see concentric LV hypertrophy
RAE vs LAE
- RIGHT ATRIAL ENLARGEMENT (RAE)
- – P wave
- – pulmonale peaked P wave with
- amplitude greater than .25 (2.5 mm) mv in leads II, III AVF
- amplitude greater than .1 mv in leads V1 & V2
- – P wave has a slight rightward axis
- – pulmonale peaked P wave with
- Left atrial enlargement (LAE)
- P wave
- mitrale “M” signs to P wave
- broad, notched P wave duration .11 sec
- amplitude of terminal negatively directed portion in V1 to greater than .1 mV or 1 mm deep and .04 sec wide
- slight axis of P wave
- mitrale “M” signs to P wave
causes of LAE vs RAE
LAE: MS, MR
RAE: Associated with TV disease or pul hypertension
- – COPD, PE, MS or MR are causes of pul hypertension

LAE

Romhilt‐Estes Scoring System for LVH
1a. R or S in limb lead: 20mm or more
1b. S in V1, V2, or V3: 25 mm or more
1c. R in V5, V6: 30 mm or more
2. Any ST shift (without digitalis)
3. Typical “strain” ST‐T (with digitalis)
4. LAD ‐ 30◦ or more

Left ventricular hypertrophy, arrow points to a “strain pattern”
Sokolow Lyon Criteria
Sokolow Lyon Criteria for LVH
R in I + S in III > 25 mm R in AVL > 11 mm RinV6 >26mm
which leads are used to determine LVH?
- limb leads (I, II, III) + precordal leads (V1-V6)
- Limb leads need @ least
- R or S wave @ least 20 mm
- PreCo leads need @ least
- 25 mm S wave in V1-2 or V3
- 30 mm R wave in V5-V6

LVH: leads 1-3 R or S wave 20 mm or more, precordal leads V1-3 S wave 25 mm or more, V5-6 R wave 30 mm or more

LVH with straining pattern, inverted T wave
causes of dominant R waves in V1
RVH
• Posterior or lateral MI
• WPW
• Hypertrophic cardiomyopathy • Muscular dystrophy
• Normal variant