Assessing for Noncompaction

Cardiomyopathy.

Is it Too Often Diagnosed?

Soheila Talebi.MD

Cardiologist / Cardiovascular imaging

Assistant Professor of Medicine

Mount Sinai St. Luke's

No Disclosures

Cardiomyopathy

Cardiomyopathies represent a group of diseases of the

myocardium with adverse effects on the heart muscle size,

shape, and function.

Traditionally cardiomyopathies were defined according to

phenotypical appearance.

Non compaction Cardiomyopathy

(NCCM)

The traditional classifications seem over simplistic

An increased awareness of this myocardial phenotype & the high quality of advanced cardiovascular imaging have a potential for :

Overdiagnosis

Overtreatment

Unnecessary follow-up

Incorporate the morphologic findings with molecular and genetic information.

Physiologic Reversible Remodeling

Sources: https://giphy.com/gifs/running-run-walk-5UDsrMd6ctz6KDXyIo and https://giphy.com/gifs/feels-really-pregnancy-EvSiDRE8oO4PC

Ethnic

Ethnic subgroups, in particular black individuals

who appear to have more pronounced

trabeculation, and are therefore more likely to

be mislabeled

Trabeculated (Non-Compacted) and Compact Myocardium in Adults: The Multi-Ethnic Study of Atherosclerosis

Pathologic remodeling

Hypertrophy of the myocardium does not

automatically imply hypertrophic cardiomyopathy.

As volume or pressure load results in hypertrophy of

the myocardium, it can also result in the

morphological appearance of LVNC, which is

different from NCCM

Failure of proliferation of

compact wall rather than

failure compaction of the

pre-existing trabecular layer

Genetic

Genetics play an important role in NCCM because 17% to 50% of patients have a family member with cardiomyopathy

In most families, an autosomal dominant pattern of inheritance is observed with variable penetrance

Sarcomere gene mutations are the most common identified and most of the genes involved are also implicated in hypertrophic and dilated CM.

Clinical manifestations include :

Clinical symptoms range from severe prenatal

manifestations to asymptomatic cardiomyopathy

presenting in adults

LV dysfunction, congestive heart failure

Ventricular tachycardia

Sudden cardiac death,

Thromboembolic complications

Role Of Imaging

Imaging has a fundamental role in the

diagnosis of LVNC such as :

Echocardiography

Cardiac MRI

CT Scan

Advantages of cardiac MRI

Cine imaging performed in different cardiac planes well

depicts the two-layered myocardium

MRI better shows myocardial trabeculae at end-diastole.

The extent of myocardial trabeculations can be accurately

assessed.

Cardiac MRI should be performed to confirm the diagnosis

of LVNC

Cardiac MRI

An end-diastolic ratio between noncompacted and compacted

layers greater than 2.3 is considered diagnostic of myocardial

noncompaction.

A thin compacted layer is a prerequisite for the diagnosis. The

maximal compacted thickness of < 8 mm was proposed as a

specific marker and prevent overdiagnosis

Cardiac MRI

Noncompacted myocardium should be measured in a plane

perpendicular to the compacted myocardium.

Generally use short-axis images to measure compacted and

noncompacted segments in the mid-cavity and basal

segments.

Cardiac MRI

When myocardial trabeculations are located principally at the

apex, short-axis images may not be perpendicular to the LV long

axis.

In this case four-chamber views to assess noncompaction-to-

compaction ratio is recommended

Late Gadolinium Enhancement

Erwin Oechslin, and Rolf Jenni JACC 2018;71:723-726

2018 American College of Cardiology Foundation

Key points

NCCM cardiomyopathy should not be defined only by Morphology

Physiologic remodeling & Pathologic remodeling

Prominent trabeculation is seen in some ethnic subgroup

In imaging report the term “noncompaction cardiomyopathy” should be replaced with a description of the trabeculations, along with risk factors such as ejection fraction, abnormal myocardial enhancement and LV dilation

Healthy subject not be labeled as a patient with LVNC, with a

life-long impact on this individual and on the health care

system

The critical judgment of a clinician must determine the

individual care plan, because the myocardial morphologic

phenotype is only 1 piece of the diagnostic puzzle