At what age should first-degree family members of individuals with Left Ventricular Non-Compaction (LVNC) be screened?

Screening Age for First-Degree Relatives of Individuals with LVNC

First-degree relatives of individuals with Left Ventricular Non-Compaction (LVNC) should begin screening at age 10-12 years and continue throughout life with periodic evaluations. 1

Initial Screening Recommendations

Children and Adolescents

• Age to begin screening: 10-12 years of age 1
• Frequency during adolescence: Every 12-18 months 1
• Earlier screening indicated for:
  • Family history of premature death from cardiomyopathy
  • Competitive athletes in intense training programs
  • Onset of symptoms (palpitations, dizziness, fatigue)
  • Clinical suspicion of early LV abnormalities 1

Adults

• Age 18-21 years: Continue screening every 5 years 1
• Beyond age 21: Continue periodic screening until at least middle age (50s) 1
• More frequent intervals are appropriate in families with:
  • Malignant clinical course
  • Late-onset LVNC 1

Screening Protocol Components

Each screening evaluation should include:

• 12-lead ECG
• Comprehensive transthoracic echocardiography 1
• Assessment for:
  • Excessive trabeculations (ratio of non-compact to compact myocardium ≥2) 2
  • LV systolic function
  • Regional wall motion abnormalities
  • Evidence of other cardiomyopathies 3

Rationale for Lifelong Screening

Several key factors support the need for lifelong periodic screening:

1. High familial prevalence: Studies show 25-30% of first-degree relatives of LVNC patients have cardiac abnormalities, including LVNC and other cardiomyopathies 4, 2

2. Variable penetrance and expression: LVNC can manifest at any age from birth through adulthood, with 63% of newly diagnosed relatives being asymptomatic 3

3. Delayed phenotype development: Similar to HCM, LVNC can develop later in life, making a single normal evaluation insufficient to rule out future disease 1

4. Varied presentation in family members: Relatives may present with LVNC, dilated cardiomyopathy, or other cardiac abnormalities rather than classic LVNC 4, 3

5. High risk of adverse outcomes: Early detection allows for appropriate management to prevent complications like heart failure, arrhythmias, and thromboembolism 5, 6

Special Considerations

• Asymptomatic carriers: Some individuals may have genetic mutations without obvious cardiac abnormalities but remain at risk for developing disease later 3

• Genetic testing: When available, genetic testing should complement imaging studies to identify at-risk family members 3

• Additional monitoring: Consider 24-hour ambulatory ECG monitoring to detect arrhythmias in relatives with any abnormal findings 1

• Early signs: Changes in LV strain and diastolic function can precede definitive hypertrophy and may warrant closer follow-up 1

Pitfalls to Avoid

• Missing subtle abnormalities: LVNC diagnosis is often missed initially; echocardiographers should be familiar with diagnostic patterns 6

• Premature reassurance: A normal echocardiogram at maturity does not definitively rule out future development of LVNC 1

• Inadequate follow-up duration: Continuing surveillance into adulthood is essential as LVNC can manifest later in life 5

• Focusing only on LVNC features: Screen for other cardiomyopathies as well, as family members may present with different phenotypes 3