Age-related changes in mitral annular disjunction: A retrospective analysis using enhanced cardiac CT.

AIMS

The current recognition of mitral annular disjunction (MAD) as an anatomical abnormality potentially associated with ventricular arrhythmias has sparked controversy regarding its prevalence and clinical implications. This study aimed to investigate the prevalence and extent of MAD in individuals with no significant structural abnormalities involving the left heart using enhanced cardiac CT, while also exploring potential factors, such as age, that may be associated with MAD.

METHODS

Systolic datasets of cardiac CT from 742 subjects were retrospectively included. MAD was determined by rotating orthogonal multiplanar reconstruction images around the central axis of the mitral annulus. The maximal distance of disjunction (D) and segments involved (SI, 0 to 5 basal segments at left ventricular wall) was quantified to evaluate the extent of separation.

RESULTS

In total, 449 (60.5%) had MAD. Subjects with MAD were significantly older (51.3 ± 19.9 years vs. 29.6 ± 20.3 years, P < 0.001). Age was found to be an independent relevant factor for MAD (OR = 1.059; 95%CI: 1.033, 1.085; P < 0.001). Subjects with MAD were then divided into 4 subgroups (G1: ≤20 years, G2: 21-40 years, G3: 41-60 years, G4: ≥61 years). D and SI of each age subgroup were 1.9 ± 0.2 mm, 2.0 ± 1.2 (G1, n = 36), 2.7 ± 0.8 mm, 2.9 ± 1.3 (G2, n = 51), 3.0 ± 0.8 mm, 3.0 ± 1.3 (G3, n = 183), and 3.0 ± 1.0 mm, 3.7 ± 1.1 (G4, n = 179). Age was an independent relevant factor associated with D (R = 0.132; β = 0.014; 95%CI: 0.004, 0.024; P = 0.007) and SI (OR = 1.030; 95%CI: 1.005, 1.055; P = 0.016).

CONCLUSIONS

MAD is a common finding on cardiac CT. Its prevalence and extent increase with age.