Table 2. Non-invasive cardiac output data at rest and during exercise. Data are means (±SD). Rest Normals CHF and Normal CO Response CHF and Abnormal CO Response p value Cardiac output (L·min-1) 5.4±1.7 4.5±1.4 5.7±1.4 0.03 Cardiac index (L·min-1·M-2) 2.9±0.78 2.2±0/61* 3.0±0.81*†  0.003 Dx/dt (ohme·sec-1) 171.3±107 92.3±52 225.4±151 <0.001 VET (msec) 174.3±36 167.3±21 154.5±17 0.14 Ejection fraction 56.5±9 43.4±17 43.0±19 0.05 Peak Exercise Cardiac output (L·min-1) 20.0±10.0 19.7±6.5 11.1±4.4*†  0.002 Cardiac index (L·min-1·M-2) 10.6±4.7 9.8±3.3 5.6±1.7*†  <0.001 Dx/dt (ohme·sec-1) 557.8±239 429.9±194 322.4±141†  0.01 VET (msec) 143.6±17 142.5±11 148.7±13 0.39 p value represents ANOVA main effect between groups. p < 0.05 vs CHF patients with a normal cardiac output response. p <0.05 vs normal subjects. VET = ventricular ejection time. Dx/dt = peak aortic flow.