Dobutamine stress echocardiography revealed a significant linear relation between transaortic pressure difference and flow in 68% of patients with aortic stenosis, with slopes varying by severity (p=0.0055).
Observational (n=50)
valor p: p=0.0055
OBJECTIVE To investigate the relation between transaortic pressure difference and flow in patients with aortic stenosis. METHODS 50 asymptomatic patients with all grades of aortic stenosis were studied using dobutamine stress echocardiography. Individual plots of mean pressure drop against flow were drawn. Comparisons were made between grades of aortic stenosis as defined by the continuity equation. RESULTS A significant linear relation between pressure difference and flow was found in 34 patients (68%). There was a significant curvilinear relation in four (8%), while no significant regression line could be fitted in 12 (24%). In the 34 patients with linear fits, the slopes (mean (SD)) were 0.08 (0.07) in mild, 0.10 (0.04) in moderate, and 0.22 (0.16) in severe aortic stenosis (p = 0.0055). CONCLUSIONS Transaortic pressure difference can be related directly to flow in many patients with all grades of aortic stenosis. However, there are individual differences in slope and intercept suggesting that resistance calculated at rest may not always be representative. Raw pressure drop/flow plots may be an alternative method of describing valve function.
Takeda et al. (Thu,) conducted a observational in Aortic stenosis (n=50). Dobutamine stress echocardiography vs. Comparisons between grades of aortic stenosis was evaluated on Relation between transaortic pressure difference and flow (p=0.0055). Dobutamine stress echocardiography revealed a significant linear relation between transaortic pressure difference and flow in 68% of patients with aortic stenosis, with slopes varying by severity (p=0.0055).