Prevalence and Clinical Impact of Myocardial Crypts in FBN1 mutation: New Insights from CT Imaging in Marfan Syndrome

Myocardial crypts are narrow invaginations of the left ventricular myocardium, detectable by cardiac MRI or CT. While common in healthy individuals (6–7% prevalence), they are more frequent in patients with myocardial disarray, such as those with hypertrophic cardiomyopathy. Similar myocardial disarray abnormalities have been described in Marfan syndrome with FBN1 mutation. We hypothesized that myocardial crypts may be more prevalent in Marfan syndrome and could potentially serve as markers of aortic disease severity. We performed a single-center retrospective study at CHU de Caen, a tertiary referral center for Marfan syndrome and related disorders. We reviewed previously acquired ECG-gated thoracic CT scans (Siemens Somatom Definition AS+ 128-slice) performed as part of the diagnostic workup in individuals with clinically and/or genetically confirmed Marfan syndrome or related conditions. A total of 101 patients with Marfan syndrome or related disorders were included, of whom 55 had confirmed FBN1 mutations. Myocardial crypts were identified in 12 FBN1+ patients (prevalence 21.8%). This prevalence was significantly higher than in the general population (21.8% vs. 6.7%, p < 0.001). No significant differences were observed between FBN1+ patients with or without myocardial crypts regarding the prevalence of mitral valve prolapse, aortic dissection, aortic surgery, arrhythmia, or left ventricular dysfunction. However, age at first aortic surgery tended to be lower in FBN1+ patients with myocardial crypts (26,4 [4–42] years vs. 38 [13–63] years, p = 0.05) Myocardial crypts appear to be more prevalent in patients with FBN1+ Marfan syndrome compared to the general population. They do not appear to correlate with a more severe phenotype. However, they may represent a novel imaging marker that could contribute to the diagnostic assessment of connective tissue disorders.