Left Ventricular Noncompaction Syndrome

Area of Science:

• Cardiology
• Genetics
• Medical Diagnostics

Background:

• Left ventricular noncompaction (LVNC) is a primary cardiomyopathy affecting the left ventricle, with potential right ventricular or biventricular involvement.
• It can co-occur with neuromuscular disorders, congenital heart defects, and chromosomal abnormalities.
• Current classifications are debated, with differing views from major cardiovascular societies regarding its genetic or unclassified status.

Purpose of the Study:

• To explore the classification challenges and diagnostic criteria of left ventricular noncompaction (LVNC).
• To discuss the genetic landscape and phenotypic overlap of LVNC with other cardiomyopathies.
• To highlight the implications of diagnostic criteria in various physiological states.

Main Methods:

• Review of existing literature and classification systems for LVNC.
• Analysis of diagnostic criteria based on trabeculated to compacted myocardium ratio.
• Examination of phenotypic overlap with hypertrophic and dilated cardiomyopathies.

Main Results:

• LVNC classification remains controversial due to its heterogeneity and differing societal categorizations.
• Diagnostic criteria for LVNC are found in individuals without cardiomyopathy, including athletes and pregnant women.
• The genetic basis of LVNC is complex, with significant overlap with other cardiomyopathies.

Conclusions:

• The traditional classification of LVNC is challenged by its complex genetics and diagnostic ambiguities.
• Accurate diagnosis of LVNC requires careful consideration of its heterogeneous nature and potential overlap with other conditions.
• Despite being often asymptomatic, LVNC carries risks including thromboembolic events, heart dysfunction, arrhythmias, and sudden cardiac death.