https://orcid.org/0000-0003-1722-6164
A 22-year-old asymptomatic Caucasian woman was referred because of an elevated NT-pro-BNP level (1225 ng/L, normal <125 ng/L) and a positive family history of unclear cardiomyopathy. Her electrocardiogram showed sinus rhythm, left axis deviation with signs of left ventricular (LV) hypertrophy, and repolarization abnormalities (Panel A). The transthoracic echocardiography revealed an asymmetrical LV hypertrophy without signs of left ventricular outflow tract obstruction at rest or under provocative Valsalva manoeuvre (Supplementary material online, Video S1).
Imaging with cardiovascular magnetic resonance (CMR) confirmed asymmetrical LV hypertrophy with a maximum wall thickness of 18 mm. CMR also showed biventricular prominent trabeculation with multiple anterior, septal and inferior deep recesses (Panel B, Supplementary material online, Video S2) and a maximum ratio of non-compacted to compacted myocardium of 2.6 (Supplementary material online, Image). Biventricular volumes and global ejection fraction were normal with a mild hypokinesia of the hypertrophied LV segments. Late Gadolinium Enhancement and post-contrast T1 mapping demonstrated focal patchy fibrosis in the hypertrophied segments and at both right ventricular insertion points (Panel C, D).
This case demonstrates that features of both LV non-compaction (LVNC) and hypertrophic cardiomyopathy (HCM) can co-exist in the same patient. The question remains whether this is a sign of an overlap of two separate entities, or whether LVNC and HCM are two different phenotypical aspects of the same underlying genetic aetiology. Single inferobasal myocardial crypts are known to occur more frequently in patients with HCM-causing mutations and may be observed in phenotype-negative but genotype-positive patients with HCM. Sarcomere protein gene mutations, such as of myosin heavy chain and myosin-binding protein C, can be observed in both HCM and LVNC, suggesting a possible common genetic origin of these cardiomyopathies.
Both HCM and LVNC are associated with arrhythmia, sudden cardiac death, cardiac embolism and heart failure. Hence, repetitive risk stratification in view of primary preventive defibrillator implantation should be performed at 1–3 year intervals. Genetic testing—which was not done in the present case—might be helpful for diagnosis and risk stratification.
Supplementary data are available at European Heart Journal online.
All authors declare no funding for this contribution.
All authors declare no conflict of interest for this contribution.
Data available on request. The data underlying this article will be shared on reasonable request to the corresponding author.
