Abstract 5729: Use of Strain and Strain Rate Imaging in the Assessment of Regional Left Ventricular Deformation: A Study in Adult Unoperated Patients with Marfan Syndrome
Background: Marfan syndrome (MFS) is a connective tissue disorder caused by mutations in the FBN1 gene. Recent studies demonstrated primary myocardial impairment in MFS using conventional echocardiography. Strain rate imaging constitutes a validated novel technique in quantifying regional changes in myocardial deformation. We sought to investigate the spatial distribution of left ventricular (LV) systolic abnormalities seen in MFS using strain rate imaging.
Methods: Seventeen un-operated MFS patients, 10 men and 7 women (mean age 36.4±3.0 years) and 19 controls matched for age, sex and body surface area, were studied. No patient had more than trivial valvular disease. All subjects underwent an echocardiographic examination. Ejection fraction (EF) was measured by Simpson’s method. 2D colour Doppler data was recorded using parasternal and apical 4-, 2- and 3-chamber views to evaluate radial and longitudinal LV systolic function respectively. Measurements were averaged over 3 consecutive cardiac cycles.
Results: Values are presented as mean ± SE. EF was significantly lower in MFS patients compared to controls (64.60±1.53% vs 71.73±0.85%, p=0.0004). Regional radial peak systolic strain rate (SRsys) was significantly reduced in the basal and mid- LV posterior wall segments when compared with controls (3.38±0.22 1/s vs 4.0±0.14 1/s, p=0.02 and 72.23±4.50% vs 93.62±2.48%, p=0.0003, respectively). Systolic strain (ϵSYS) was also significantly reduced in the same posterior wall segments (3.08±0.13 1/s vs 3.95±0.18 1/s, p=0.0005 and 66.57±3.47% vs 95.94±3.11%, p=0.0001, respectively). Both longitudinal SRsys and ϵSYS were significantly reduced in the basal, mid- and apical segments of the interventricular septum, lateral, inferior, anterior and posterior LV walls in MFS patients. In a multiple regression analysis including age, sex and systolic blood pressure, MFS was strongly correlated with reduced regional systolic LV deformation (p<0.001).
Conclusions: Our preliminary data showed a uniform reduction in regional LV systolic deformation in MFS patients. This could be attributed to fibrillin-1 deficiency in the cardiac extracellular matrix. Treatment may need to be tailored to prevent further deterioration by supporting LV function.