Effects of dobutamine on Doppler echocardiographic indexes of aortic stenosis

J Am Coll Cardiol. 1996 Nov 1;28(5):1206-13. doi: 10.1016/S0735-1097(96)00287-2.


Objectives: This study sought to assess the diagnostic implications of the flow dependence of Doppler echocardiographic indexes of aortic valve stenosis.

Background: Although valve area has been shown to change with alterations in flow rate, the diagnostic consequences of this phenomenon remain unknown. Valve resistance has been suggested as a more stable index for evaluating aortic stenosis.

Methods: A low dose dobutamine protocol was performed in 35 patients with aortic stenosis. Hemodynamic indexes were obtained by Doppler echocardiography at baseline and at each dobutamine dose.

Results: As a result of the shortening of the systolic ejection period, flow increased from (mean +/- SD) 164 +/- 48 to 229 +/- 102 ml/s (p < 0.0001). At peak flow, valve area increased by 28% (from 0.5 +/- 0.2 to 0.6 +/- 0.3 cm2, p < 0.0001), whereas valve resistance decreased by 4% (from 498 +/- 252 to 459 +/- 222 dynes.s.cm-5, p = 0.04). This observed change in resistance was smaller than that for valve area (p < 0.01). The flow dependence of valve area varied among individual patients (p < 0.0001). Multivariate analysis identified calcific degenerative etiology (beta 0.29, p = 0.002), left ventricular velocity of fiber shortening (beta 0.22, p = 0.01), baseline flow (beta -0.28, p = 0.04) and amount of flow increased induced by dobutamine (beta 0.90, p < 0.0001) as factors related to valve area flow dependence.

Conclusions: Although all Doppler echocardiographic indexes of aortic stenosis are affected by flow, valve resistance is more stable than valve area under dobutamine-induced hemodynamic changes. Baseline valve area may be unreliable in patients with calcific degenerative aortic stenosis and low output states.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Aortic Valve / drug effects
  • Aortic Valve / physiopathology
  • Aortic Valve Stenosis / diagnostic imaging*
  • Aortic Valve Stenosis / physiopathology
  • Dobutamine*
  • Echocardiography, Doppler*
  • Female
  • Hemodynamics / drug effects
  • Humans
  • Male
  • Middle Aged
  • Regional Blood Flow / drug effects


  • Dobutamine