Extra-Mitral Abnormalities in Nonsyndromic Mitral Valve Prolapse Assessed By Means of Cardiovascular Magnetic...

Mitral valve prolapse (MVP) reflects a connective tissue abnormality of the mitral leaflets, but systemic manifestations beyond the valve in nonsyndromic MVP remain uncertain. Cardiovascular magnetic resonance (CMR) allows a comprehensive assessment of cardiac chambers, aortic dimensions, and skeletal indexes. We investigated systemic morphofunctional features suggestive of connective tissue alterations in nonsyndromic MVP.

In this single-centre, retrospective case-control study, 120 patients with MVP without more than mild mitral or aortic regurgitation, bicuspid aortic valve, hypertension, competitive sport, or known or suspected syndromic connective tissue disease were matched 2:1 for age, sex, body surface area (BSA), and body mass index with 60 control subjects undergoing CMR.

Compared with control subjects, subjects with MVP showed greater aortic annulus (12.9 ± 1.8 mm/m² vs 12.1 ± 1.3 mm/m²; P = 0.003), aortic root (18.5 [interquartile range (IQR) 17.1-20.3] vs 17.3 [IQR 15.8-18.7] mm/m²; P < 0.001), Haller index (2.7 [IQR 2.4-3.0] vs 2.6 [IQR 2.4-2.8]; P = 0.021), and kyphosis angle (37.0 [IQR 29.0-40.0] vs 27.5 [IQR 22.0-31.5]; P < 0.001). Subjects with MVP also exhibited higher extracellular volume, T2-mapping values, left ventricular end-diastolic and end-systolic volumes and mass, and left atrial volume. After controlling for sex, age, and BSA, MVP remained associated with the dimensions of the aortic annulus (β = 1.34; P = 0.001), aortic root (β = 1.93; P = 0.001), Haller index (β = 0.21; P = 0.008), and kyphosis angle (β = 8.46; P < 0.001). No excess of other connective tissue disorder features was observed compared with control subjects.

In this patient cohort, nonsyndromic MVP was associated with subtle but significant morphofunctional changes in the cardiac chambers, proximal aorta, and thoracic skeleton. Whether these findings potentially reflect underlying connective tissue disorders, warrants further longitudinal studies on their genetic background and clinical implications.