We evaluated CMR exams of 5 patients with a diagnosis of cardiac fibroma [(4 females, 80%), mean age 11 years (range 5-20)]. They had ECG alterations but no symptoms. All studies were performed using a 1.5 T MR Scanner.
The standard protocol comprises:
· bright blood cine images (steady-state free precession techniques) short axis, 2,3 and 4 chambers;
· T1 and T2 weighted images, double-inversion recovery fast-spin echo short axis (black-blood technique);
· first-pass perfusion images by fast gradient recalled-echo-planar technique immediately after a gadolinium bolus injection;
· delayed enhancement images using an inversion-recovery segmented gradient-echo sequence (to null normal myocardium) 10 minutes after gadolinium administration (cumulative dose, 0.1 mmol/kg gadobutrol), late gadolinium enhancement (LGE);
· T1-mapping, using a Modified-Look-Locker- Inversion-Recovery (MOLLI) sequence with 3 inversion pulses (4-(1)-3-(1)-2, Matrix 192 × 124, FOV 224 × 279 mm2);
· T1-mapping was repeated 10 min after the administration of contrast media for ECV calculation.
The evaluation of T1 relaxation-time and ECV values was based on 3 short-axis slices being representative for apical, mid and basal myocardium (Fig. 2).
Fig. 2: Fig. 2: native T1 mapping (a) and T1 mapping after the administration of contrast media (b). We used dedicated software to calculate the T1 values of the myocardium and the ECV on the three slices obtained (basal, mid and apical)
Fig. 2
Fibromas involve in all cases the interventricular septum with a mean size of 5.5 cm (Fig.3).
Fig. 3: Fig. 3: a) Girl 5 years old with a voluminous mass that arises in the posterior interventricular septum, mean size of 5.5 cm, which slightly reduces the size of the ventricular cavity, on the cine-short axis sequence; b) Young woman, 14-year-old, who came to our observation for suspected asymmetric septal hypertrophy: CMR shows the presence of a large mass in the basal and mild septum (cine- long axis 4 chamber)
Fig. 3
The T1 native values of the tumor were similar to the T1 of myocardial tissue (900±50 ms), although different in the same patient compared to healthy segments. The extracellular volume fraction (ECV) of the mass was higher than that of the myocardium (>40% vs. 23-26%, respectively) (Fig.4).
Fig. 4: Fig. 4: The T1 native values of the tumor is similar to the T1 of myocardial tissue (900±50 ms), although different in the same patient compared to healthy segments. The extracellular volume fraction (ECV) of the mass was higher than that of the myocardium (>40% vs. 23-26%, respectively
Fig. 4
The tumors were slightly hypointense on T2-weighted images (Fig.5) and isointense on T1-weighted images relative to muscle, due to their dense and fibrous nature.
Fig. 5: Fig.5: The tumor is slightly hypointense to myocardium on T2-weighted images due to their dense and fibrous nature; moreover, it shows a homogeneous signal.
Fig. 5
They showed little or no enhancement during the early phases after administration of intravenous contrast but hyperenhancement on LGE (Fig.6).
Fig. 6: Fig. 6: Cardiac fibroma shows little or no enhancement during the early phases after administration of intravenous contrast (a) and hyperenhancement on LGE (b)
Fig. 6