Objective: To measure aortic stiffness and global left ventricular (LV) function in patients with ankylosing spondylitis (AS) and no clinical evidence of heart disease.
Methods: Fifty-seven consecutive patients with AS (54 males, three females, mean age 41.78+/-10.02 years) without clinical evidence of cardiac involvement and 78 healthy subjects (73 males, five females, mean age 39.92+/-9.11 years) underwent complete echocardiographic study. Aortic stiffness was determined non-invasively by aortic distensibility (AoD) and the global LV function was evaluated by the myocardial performance index (the Tei index).
Results: AoD in patients with AS [(2.21+/-0.24)x10(-6) cm(2) dyn(-1)] was decreased compared to controls [(2.58+/-0.19) )x10(-6) cm(2) dyn(-1), p<0.01], confirming that aortic stiffness is increased in AS. The LV Tei index was significantly increased in the patient group compared to the control group (0.392+/-0.031 vs. 0.370+/-0.034, p<0.01). The ejection fraction (EF) did not differ between the two groups (p>0.05). In multivariate linear regression analysis, AoD was significantly associated with the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and LV isovolumic relaxation time (IVRT) whereas the LV Tei index was associated with BASDAI and the LV mass index.
Conclusions: Patients with AS and no clinical evidence of cardiac disease have increased stiffness of the aorta and decreased global myocardial performance and both of these abnormal measurements correlate with disease activity. The abnormal Tei index may reflect an early manifestation of cardiac dysfunction in these patients.