Left ventricular non-compaction (LVNC) is a rare congenital cardiomyopathy characterized by prominent trabeculations and deep recesses in the left ventricle. Development of LVNC occurs during embryonic myocardial maturation and may vary in severity; diagnostic criteria encompass echocardiographic and cardiac magnetic resonance imaging methods. Management lacks specific treatments, though family screening and genetic testing are recommended, alongside devices for patients with decreased systolic function.

1. LEFT VENTRICULAR NON- COMPACTION
SHORT REVIEW
DR MAHENDRA
CARDIOLOGY,JIPMER
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2. INTRODUCTION
• Spongy appearance of the myocardium first described by
Grant in 1926.
• Developmental considerations-
• development of the myocardial architecture which passes
through four distinct steps
• (i) early heart tube
• (ii) emergence of trabeculations
• (iii) trabecular remodeling
• (iv) development of the multilayered spiral system
• Emergence of trabeculations and trabecular remodeling are
the key steps to understand LVNC
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3. • Emergence of trabeculations-
• emerge after looping of the primitive heart tube at the end of
the fourth week of gestation.
• trabeculation patterns are ventricle-specific
• trabeculations in the LV are generally thicker and the
corresponding intertrabecular spaces are larger at this
embryonic stage.
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4. • Trabecular remodeling-
• remodelling starts after completion of ventricular septation at
8 weeks of gestation in human.
• Increase in ventricular volumes results in compression of the
trabeculations with an increase in the thickness of the
compacted myocardium.
• compaction process coincides with the invasion of epicardial
coronary arteries and vascularization of the myocardium
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5. • progresses from-
• epicardium to the endocardium
• base to the apex
• septum to the free wall in the LV
• more in LV than right ventricle
• time of arrest of normal embryonic myocardial maturation
determines the severity and extension of LVNC
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8. • Left ventricular noncompaction cardiomyopathy rare
congenital disorder characterized by
1. Prominent LV trabeculae
2. Deep intertrabecular recesses communicate with venricular
cavity
3. Thin compacted layer
4. Noncompacted and compacted ratio >2 in end systole
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9. • persistent sinusoids
• describe ventriculo-coronary arterial communications or
intertrabecular spaces connecting the ventricular cavity with
the epicardial coronary artery system through the capillary
bed.
• seen in pulmonary atresia with intact ventricular septum.
• hypertrabeculation-
• increased number of normally formed trabeculations
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12. PREVALENCE
• In adults based on Echo ranges fom 0.014% to 1.3%
• In Australian children with cardiomyopathy prevalence higher-
5% to 9.2%.
• phenotype of noncompaction can vary even within familial
cases and range from clinically benign to fatal.
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13. Genetics of LVNC
• Sporadic and familial form.
• AD more common than X-linked inheritance
• Familial recurrence between 18 and 50%
• Mutations in the G4.5 gene on Xq28 resulting Barth syndrome
with DCM and LVNC in a pediatric population.
• Loci for LVNC were also described on chromosome 1, 5, and
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15. • Acquired NCLV-
• Young athlete
• Pregnancy
• Sickle cell anemia
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19. CLASSIFICATION
• AHA classifies LVNC as a genetic cardiomyopathy.
• ESC and WHO classify LVNC as an unclassified
cardiomyopathy.
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20. Diagnostic criteria-
• Normal variants-
• Boyd et al. reported the frequency and localization of
prominent LV trabeculations at autopsy in 474 normal hearts
• 53% of them exhibited two or more.
• More than three prominent trabeculations were observed in
only 3%.
• but none of the hearts had more than five.
• Most of the trabeculations (85%) were septomarginal bundles
inserting into both the free wall and the septum
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21. Non-compaction
(California criteria)
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23. Zurich criteria
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24. Vienna criteria
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26. Limitations of echocardiographic criteria
• poor correlation between three echocardiographic definitions
• 24% of the study population fulfilled one or more
echocardiographic definitions for LVNC.
• only 30% fulfilled all three criteria.
• 8% of apparently healthy individuals also satisfied one or
more diagnostic criteria for LVNC
• Contrast echocardiogram is useful to better image
intertrabecular spaces
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31. Cardiac magnetic resonance imaging
• Method of choice to confirm or rule out the diagnosis of LVNC
• The NC areas are most commonly found in the apical and
lateral portions of the left ventricle
• ratio of NC to C layers > than 2.3 at end diastole (Petersen et
al.)
• Trabeculated LV mass >20% of global LV mass (Jacquier et al.)
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Zuccarino et al. AJR:204 May 2015

34. • Differential diagnosis-
• Apical form of hypertrophic cardiomyopathy, a combination of
both apical hypertrophic cardiomyopathy and LVNC
• hypertensive cardiomyopathy
• endocardial fibroelastosis
• abnormal chords
• Apical thrombus, or tumours
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35. ASSOCIATED CONDITIONS
• Coronary cameral fistulas
• LVOT abnormalities
• Ebstein’s anomaly
• Bicuspid aortic valve
• Transposition of great vessels
• Metabolic diseases and genetic syndromes, including the
Barth syndrome, the Charco-Marie-Tooth disease
• Muscular dystrophy
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37. MANAGEMENT
• No specific treatment available
• Family members of proband should be screened using ECHO
• Genetic testing may useful in identifying familial forms
• Anticoagulation-(INR 2-3)
1. Decreased systolic function with EF below 40%
2. History of thromboembolism
3. Atrial fibrillation
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38. • ICD/biventricular pacing-
• no robust data available for guideline
• indication for device therapy as per current guideline.
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41. Take home message
• Many pt with trabeculae but normal LV function diagnosed
as NVLC.
• Should not labeled unless truly meet diagnostic criteria.
• Jenni criteria appear to best at present.
• Trabeculation may progress or change under physiologic
condition like pregnancy, serial evaluation is necessary.
• Difference in LV mass and trabecular feature between racial
background
• Screening of relative is crucially important.
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42. THANK YOU
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