Left ventricular function in children with the Marfan syndrome.

Aortic dilatation and heart valve lesions are common in the Marfan syndrome but whether primary alterations occur in left ventricular (LV) function has not been studied hitherto. LV size, mass and systolic as well as diastolic function were studied by M-mode and Doppler echocardiography and cine magnetic resonance imaging in 22 Marfan children aged 3.0-15.4 years and in 22 age-matched healthy children. No child had significant valve disease. Heart rate and systolic blood pressure were comparable in the groups but diastolic blood pressure was higher in the controls (67 +/- 7 mmHg vs 62 +/- 8 mmHg, P = 0.030). No statistically significant differences were found in LV size, mass or systolic function. The Marfan children had slower LV peak diameter lengthening rates (106 +/- 27 mm.s-1 vs 132 +/- 29 mm.s-1, P = 0.004), prolonged relaxation times (155 +/- 22 ms vs 140 +/- 19 ms, P = 0.023), slower deceleration of the early transmitral velocity (580 +/- 144 cm.s-1 vs 720 +/- 160 cm.s-2, P = 0.006), and smaller early-to-late peak velocity ratios (1.99 +/- 0.40 vs 2.29 +/- 0.46, P = 0.031). These data indicate that LV early diastolic function (relaxation) is impaired in the Marfan syndrome. Weakened elastic recoil due to the underlying connective tissue abnormality may best explain this novel observation.