Echocardiographic Assessment of the Cardiomyopathies

Notes

Cards

• basicIII.C-001
  State the echocardiographic diagnostic wall-thickness criterion for HCM.
  → Unexplained LV wall thickness ≥ 15 mm in any segment (or ≥ 13 mm in a first-degree relative of a patient with HCM), not explained by loading conditions.
• basicIII.C-002
  Define resting-obstructive vs latent (provokable) HCM.
  → Resting-obstructive: LVOT gradient > 30 mmHg at rest. Latent-obstructive: rest gradient < 30 but ≥ 30 with provocation (Valsalva, amyl nitrite, exercise). Severe obstruction: > 50 mmHg.
• basicIII.C-003
  How does the CW jet shape of dynamic HCM obstruction differ from valvular AS?
  → HCM: late-peaking, 'dagger-shaped' or 'scimitar' concave-to-baseline systolic envelope. AS: early-peaking, symmetric parabolic envelope.
• basicIII.C-004
  Name three maneuvers that provoke LVOT obstruction in HCM.
  → Valsalva strain phase, amyl nitrite inhalation, standing (all decrease preload/afterload). Exercise also provokes. Squatting or hand-grip decreases obstruction.
• basicIII.C-005
  Which direction is the MR jet typically in HCM with SAM, and why?
  → Posteriorly directed. The anterior mitral leaflet moves into the LVOT (SAM), disrupting coaptation and creating a posteriorly directed MR jet.
• basicIII.C-006
  Give three factors that increase sudden cardiac death risk in HCM.
  → 1) Family history of SCD. 2) Unexplained syncope. 3) Non-sustained VT on Holter. 4) Wall thickness ≥ 30 mm. 5) Abnormal blood pressure response to exercise (flat or drop). LGE on cMRI also increases risk.
• basicIII.C-007
  How does the strain pattern in apical HCM differ from that of cardiac amyloid?
  → Apical HCM: REDUCED apical strain (thickened, dysfunctional apex). Cardiac amyloid: PRESERVED apical strain with reduced basal/mid strain ('cherry-on-top' apical sparing pattern).
• basicIII.C-008
  What ECG-echo mismatch is highly suggestive of cardiac amyloidosis?
  → Low QRS voltage on ECG despite echocardiographic LVH ('voltage-mass mismatch'). Amyloid infiltrates the myocardium, increasing wall thickness without proportional voltage.
• basicIII.C-009
  List four echo features of cardiac amyloidosis.
  → 1) Concentric LVH (often ≥ 12 mm). 2) 'Sparkling' or 'granular' myocardial appearance. 3) Bi-atrial enlargement. 4) Small pericardial effusion. 5) Thickened valve leaflets and interatrial septum. 6) Apical-sparing GLS pattern.
• basicIII.C-010
  Etiologies of dilated cardiomyopathy (name 5).
  → Idiopathic; familial (~30%); viral (Coxsackie B, adenovirus, HIV); toxic (alcohol, anthracycline, cocaine); tachycardia-induced; peripartum; endocrine (thyroid, acromegaly); nutritional (thiamine — beriberi, selenium — Keshan disease); autoimmune; infiltrative (as restrictive/mixed).
• basicIII.C-011
  What genetic condition combining skeletal and cardiac disease commonly presents with asymptomatic LV dysfunction until late in the disease course?
  → Duchenne muscular dystrophy — X-linked dystrophin mutation. Both skeletal and cardiac muscle affected; asymptomatic LV dysfunction early (limited activity), heart failure/arrhythmias later.
• basicIII.C-012
  Define peripartum cardiomyopathy.
  → New-onset LV EF < 45% during late pregnancy or within ~5 months postpartum, without another identifiable cause of heart failure.
• basicIII.C-013
  What is Takotsubo (stress) cardiomyopathy's classic morphology?
  → Apical akinesis/ballooning with basal hyperkinesis ('octopus pot' or 'apical ballooning'). Can produce dynamic LVOT obstruction from hyperdynamic base. Typically reversible over days-weeks.
• basicIII.C-014
  Jenni criteria for LV non-compaction?
  → End-systolic ratio of non-compacted to compacted LV myocardium > 2:1. Deep intertrabecular recesses that communicate with the LV cavity, typically at the apex and lateral wall.
• basicIII.C-015
  Two most common cardiac lesions in Chagas disease?
  → Apical LV aneurysm (dyskinesis with preserved basal function) and conduction disease (classically RBBB + left anterior fascicular block). Caused by Trypanosoma cruzi.
• basicIII.C-016
  Relative wall thickness cutoff most sensitive/specific for athletic remodeling vs early HCM?
  → RWT < 0.6 (eccentric remodeling from volume-based training) suggests athlete's heart. Concentric LVH with RWT > 0.6 raises concern for HCM.
• basicIII.C-017
  How does deconditioning distinguish athlete's heart from HCM?
  → Athlete's heart regresses (walls thin, chamber normalizes) with 3–6 months of deconditioning. HCM does not regress.
• basicIII.C-018
  Fabry disease — cardiac phenotype and key echo/ECG feature?
  → X-linked α-galactosidase A deficiency → glycolipid accumulation → concentric LVH mimicking HCM. Classic ECG: short PR interval. Echo: 'binary' appearance of the LV endocardium. Enzyme replacement therapy available.
• basicIII.C-019
  Etiologies of restrictive cardiomyopathy (name 4).
  → Cardiac amyloid (AL, ATTR), sarcoidosis, hemochromatosis, endomyocardial fibrosis (Löffler / hypereosinophilic syndrome), and radiation.
• basicIII.C-020
  How does sarcoidosis typically appear on echo?
  → Patchy involvement — can mimic DCM, HCM (basal septal thinning is characteristic), or restrictive. Often accompanied by conduction disease (AV block) and ventricular arrhythmias. FDG-PET or cMRI often needed for diagnosis.
• basicIII.C-021
  How does arrhythmogenic RV cardiomyopathy (ARVC/D) present on echo?
  → RV outflow tract enlargement, regional RV aneurysms/microaneurysms ('bulges'), reduced RV FAC (< 33%). Task Force Criteria also include ECG features (epsilon wave, T-wave inversions V1–V3) and family history.
• basicIII.C-022
  For HCM, which strain finding correlates with clinical outcome?
  → E/e′ predicts clinical outcome. Higher E/e′ correlates with worse prognosis. Reduced GLS also correlates with adverse outcomes.
• basicIII.C-023
  Endomyocardial fibrosis (Löffler / hypereosinophilic) — echo features?
  → Apical LV and RV obliteration with layered thrombus, restrictive filling, and biatrial enlargement. Associated with peripheral eosinophilia (hypereosinophilic syndrome).
• basicIII.C-024
  Which type of amyloid is more common with cardiac involvement — AL or ATTR?
  → Historically AL (immunoglobulin light chain, in myeloma). Now increasingly recognized wild-type ATTR (age-related, older men) — treatable with tafamidis. Hereditary ATTR (mutant) also occurs.
• basicIII.C-025
  What is Loeffler's endocarditis and how does it differ from tropical endomyocardial fibrosis?
  → Löffler endocarditis: temperate-zone hypereosinophilic syndrome with acute necrotic phase → thrombotic phase → fibrotic phase. Tropical endomyocardial fibrosis: endemic in equatorial Africa/Asia; presents in the fibrotic stage. Both cause restrictive cardiomyopathy with layered apical thrombus.
• basicIII.C-026
  How does apical HCM (Yamaguchi variant) present on ECG and echo?
  → ECG: giant negative T-waves in precordial leads. Echo: apical wall thickness ≥ 15 mm confined to LV apex; 'spade-shaped' LV cavity at end-diastole; reduced apical strain. No LVOT obstruction (unlike septal HCM).
• basicIII.C-027
  Give two ECG features that suggest cardiac amyloidosis in a patient with LVH on echo.
  → 1) Low QRS voltage (< 5 mm in limb leads, < 10 mm in precordial leads) despite echo LVH — 'voltage-mass mismatch.' 2) Pseudo-infarct pattern (Q waves) in absence of true infarction.
• basicIII.C-028
  Which specific noninvasive test can diagnose ATTR cardiac amyloid without biopsy?
  → Technetium-99m pyrophosphate (99mTc-PYP) scintigraphy. Grade 2 or 3 uptake (myocardial-to-contralateral chest ratio > 1.5 at 1 hour) in the ABSENCE of a monoclonal protein is diagnostic for ATTR.
• basicIII.C-029
  How does cardiac sarcoidosis differ from HCM on echo?
  → HCM: symmetric or asymmetric LVH with preserved LV function, no LGE bimodal pattern. Sarcoid: patchy involvement — often 'basal septal thinning' with regional wall-motion abnormalities, conduction disease (AV block), and multifocal LGE on cMRI. Sarcoid can also mimic DCM.
• basicIII.C-030
  Define non-obstructive HCM.
  → HCM (unexplained LV wall thickness ≥ 15 mm) WITHOUT a resting or provoked LVOT gradient > 30 mmHg. May still have significant symptoms and SCD risk.
• basicIII.C-031
  State three medications useful in symptomatic obstructive HCM.
  → 1) β-blockers (first-line, reduce heart rate, LVOT gradient). 2) Non-DHP calcium channel blockers (verapamil, diltiazem — second-line if β-blocker contraindicated). 3) Disopyramide (potent negative inotrope). Mavacamten (cardiac myosin inhibitor) is now approved for obstructive HCM.
• basicIII.C-032
  What is Takotsubo cardiomyopathy's key echocardiographic feature?
  → Apical akinesis or ballooning with basal hyperkinesis (the classic 'apical ballooning' pattern). Also 'inverted Takotsubo' with basal hypokinesis is described. Reversible over days-weeks in most patients.
• basicIII.C-033
  Which LGE pattern on cMRI suggests HCM vs sarcoid vs amyloid?
  → HCM: patchy midwall LGE, often at RV insertion points or areas of maximal hypertrophy. Sarcoid: multifocal midwall or subepicardial LGE, often patchy. Amyloid: diffuse global subendocardial LGE that becomes transmural in advanced disease.
• basicIII.C-034
  How is LV non-compaction defined on echo?
  → Jenni criteria: end-systolic ratio of non-compacted to compacted layer > 2:1. Deep intertrabecular recesses that communicate with the LV cavity. Apical and lateral segments most commonly involved.
• basicIII.C-035
  How does dobutamine stress echo differentiate hibernating myocardium from scar?
  → Hibernating myocardium shows CONTRACTILE RESERVE — improvement at low dose (5–10 μg/kg/min); may show biphasic response at higher doses (worsening = ischemia + viability, best surgical target). Scar shows NO contractile reserve at any dose.