Hypertrophic cardiomyopathy and left ventricular non-compaction cardiomyopathy: two in one

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).