Table 1 Measures of resting and low-dose dobutamine stress echocardiography in a patient with low flow, low gradient, low EF aortic stenosis
Echocardiographic parameters | Resting | Stage I 5 μ/kg/min | Stage II 10 μ/kg/min | Stage III 15 μ/kg/min | Stage IV 20 μ/kg/min |
|---|---|---|---|---|---|
Heart rate (beat per minute) | 52 | 54 | 53 | 55 | 60 |
Peak aortic jet velocity (m/s) | 2.6 | 2.6 | 3.0 | 3.0 | 3.4 |
Mean pressure gradient (mmHg) | 16 | 17 | 22 | 22 | 26 |
Peak LVOT velocity (m/s) | 0.69 | 0.73 | 0.93 | 0.93 | 1.04 |
Aortic valve area (cm2) | 0.93 | 0.82 | 1.02 | 1.06 | 1.07 |
Stroke volume index (ml/m2) | 32 | 31 | 39 | 40 | 43 |
Systolic ejection time (ms) | 346 | 343 | 322 | 323 | 300 |
Flow rate (ml/s) | 168 | 159 | 208 | 217 | 255 |
LV ejection fraction (%) | 42 | NA | NA | NA | 50 |
Septal S′ (cm/s) | 6 | NA | NA | NA | 8 |
Lateral annular S′ (cm/s) | 7 | NA | NA | NA | 12 |