Background: To evaluate temporal changes of left ventricular (LV) geometry and diastolic function after aortic valve replacement (AVR) in patients with aortic stenosis (AS), 38 patients (mean age, 57.8±12.1 years) underwent low-level supine bicycle exercise Doppler echocardiography (EDE) 59.2±33.0 months after AVR. During EDE, early diastolic peak velocity of transmitral flow (E) and annular movement (E’) was measured. EDE was performed in 19 sex- and age-matched controls for comparison. After AVR, LV mass index (LVMI)/LV end-diastolic volume index (LVEDVI) decreased up to 27.4±32.7%. Although pre-AVR E velocity was similar, pre-AVR E’ velocity was lower (4.3±1.6 versus 7.7±1.6 cm/sec, p<0.005) which resulted in higher E/E’ in AS patients (16.7±5.4 versus 9.3±1.8, p<0.001). Pre-AVR LVMI/LVEDVI showed negative correlation with E’ (r=0.499, p<0.001) and positive correlation with E/E’ (r=0.376, p=0.011). E/E’ did not change significantly after AVR (from 16.7±5.4 to 15.5±4.7, p=0.573) despite E’ increase after AVR (from 4.3±1.6 to 6.3±1.8 cm/sec, p<0.001). Both E and E’ increased progressively with exercise and the degree of E velocity increase during exercise was not different (p=0.675), whereas E’ velocity increase was more prominent in normal controls than in AS patients (p<0.001). The peak E/E’ during exercise was higher in AS patients (17.8±5.0 versus 10.4±1.7, p<0.05). Prevalence of patients with peak E/E’>13 during EDE was higher in AS patients (89.5% [34/39] versus 0% [0/19], p<0.001). When used separately in multivariate analysis, both pre-AVR and post-AVR LVMI/LVEDVI were the only independent factor associated with peak E/E’ during EDE. Conclusions Persistent LV diastolic dysfunction exists up to 5 years after uneventful AVR and failure in normal physiologic augmentation of LV relaxation during exercise associated with incomplete or inadequate regression of LVH is the main mechanism
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