Noncompaction of the LV Myocardium: Echocardiographic Diagnostic Criteria and the Problem of Overdiagnosis
Echocardiographic Criteria for Diagnosing LVNC
Several echocardiographic criteria are used to differentiate benign left ventricular trabeculation from pathological noncompaction myocardium (LVNC).
| Criterion | Diagnostic Threshold for LVNC |
|---|---|
| Jenni | Ratio of noncompacted endocardial (N) to compacted epicardial (C) myocardium N/C > 2 (measured from PSAX at end-systole) |
| Chin (index) | Ratio X/Y < 0.5 |
| Sollberger | More than three trabeculations protruding from the LV wall (with myocardial echogenicity), apical to the papillary muscles, visible in a single plane at end-diastole |
Additional Components of Jenni's Criteria
In addition to the N/C ratio > 2, Jenni's criteria include: absence of associated cardiac anomalies, presence of multiple prominent trabeculations at end-systole, and communication of trabecular recesses with the ventricular cavity.
According to Sollberger's criteria, perfusion of intertrabecular spaces from the LV cavity, visualized by color Doppler mapping, is important.
Methodological Aspects of the Study
When performing echocardiography to assess LVNC, consider the following:
• Optimal image resolution and correct focus positioning in the apical area are important.
• In suboptimal acoustic windows, intravenous ultrasound contrast agents can be used for better visualization of trabecular spaces.
Differential Diagnosis and the Problem of Overdiagnosis
Benign LV trabeculation should be distinguished from pathological LVNC based on the given criteria. The differential diagnosis includes: intramyocardial hematoma/abscess, thrombi, fibroma, false chords, and apical hypertrophic cardiomyopathy (HCM).
Frequently asked questions
What N/C ratio corresponds to the LVNC diagnosis according to Jenni's criteria?
The ratio of noncompacted (N) to compacted (C) myocardium greater than 2 (N/C > 2), measured from PSAX at end-systole.
In which phase of the cycle and from which view is the measurement taken according to Jenni?
The thickness of the compacted and noncompacted layers is measured from the parasternal short axis (PSAX) at end-systole.
What does the Chin index consider?
LVNC is determined by a ratio of X/Y < 0.5.
With which conditions is LVNC differentiated?
With intramyocardial hematoma/abscess, thrombi, fibroma, false chords, and apical HCM.
What should be done in case of poor acoustic windows?
Use intravenous ultrasound contrast agents for better visualization of trabecular spaces; optimal resolution and focus positioning in the apical area are important.