OBJECTIVE: Impedance Cardiography (ICG) has been shown to be a feasible and accurate method for non-invasive measurement of cardiac index (CI). Aim of this investigation was the correlation of hemodynamic variables under exercise as measured by a specific ICG-monitor (Solar IKG-Modul, Version 3.0, GE-Healthcare, Freiburg, Germany) with metabolic variables. METHODS: Ten healthy volunteers were included in the investigation doing ergometer exercise (5 min equilibration followed by 5 min each at 50, 75, 100 and 125 W). Hemodynamic parameters were obtained by ICG. Metabolic variables were assessed by indirect calorimetry with the Deltatrac II Metabolic monitor using a helmet system for spontaneous respiration. RESULTS: CI increased throughout exercise (baseline: 3.0 +/- 0.4 l/min/m(2); 125 W: 4.8 +/- 0.5 l/min/m(2)). Heart rate (baseline: 87.2 +/- 13.4 bpm; 125 W: 152.7 +/- 22.4 bpm) and contractility (velocity index) (baseline: 48.9 +/- 9.3/1000 s; 125 W: 70.5 +/- 10.0/1000 s) showed a continuous rise while the stroke index decreased after an initial rise (baseline: 35.0 +/- 4.6 ml/m(2); 50 W: 37.6 +/- 4.9 ml/m(2); 75 W: 41.2 +/- 5.9 ml/m(2); 125 W: 32.3 +/- 6.1 ml/m(2)). VO(2) (baseline: 335.2 +/- 84.1 ml/min; 125 W: 1298.9 +/- 282.3 ml/min) and VCO(2)(baseline: 255.4 +/- 74.5 ml/min; 125 W: 1342.5 +/- 282.5 ml/min) increased throughout exercise. There was a good correlation in the individual fits between hemodynamic and metabolic variables. CONCLUSION: CI in healthy volunteers, as measured by the Solar IKG-Modul, correlates well with O(2)-consumption and CO(2)-production in individual subjects, thus indicating the metabolic needs under exercise conditions in healthy individuals.
OBJECTIVE: Impedance Cardiography (ICG) has been shown to be a feasible and accurate method for non-invasive measurement of cardiac index (CI). Aim of this investigation was the correlation of hemodynamic variables under exercise as measured by a specific ICG-monitor (Solar IKG-Modul, Version 3.0, GE-Healthcare, Freiburg, Germany) with metabolic variables. METHODS: Ten healthy volunteers were included in the investigation doing ergometer exercise (5 min equilibration followed by 5 min each at 50, 75, 100 and 125 W). Hemodynamic parameters were obtained by ICG. Metabolic variables were assessed by indirect calorimetry with the Deltatrac II Metabolic monitor using a helmet system for spontaneous respiration. RESULTS: CI increased throughout exercise (baseline: 3.0 +/- 0.4 l/min/m(2); 125 W: 4.8 +/- 0.5 l/min/m(2)). Heart rate (baseline: 87.2 +/- 13.4 bpm; 125 W: 152.7 +/- 22.4 bpm) and contractility (velocity index) (baseline: 48.9 +/- 9.3/1000 s; 125 W: 70.5 +/- 10.0/1000 s) showed a continuous rise while the stroke index decreased after an initial rise (baseline: 35.0 +/- 4.6 ml/m(2); 50 W: 37.6 +/- 4.9 ml/m(2); 75 W: 41.2 +/- 5.9 ml/m(2); 125 W: 32.3 +/- 6.1 ml/m(2)). VO(2) (baseline: 335.2 +/- 84.1 ml/min; 125 W: 1298.9 +/- 282.3 ml/min) and VCO(2)(baseline: 255.4 +/- 74.5 ml/min; 125 W: 1342.5 +/- 282.5 ml/min) increased throughout exercise. There was a good correlation in the individual fits between hemodynamic and metabolic variables. CONCLUSION: CI in healthy volunteers, as measured by the Solar IKG-Modul, correlates well with O(2)-consumption and CO(2)-production in individual subjects, thus indicating the metabolic needs under exercise conditions in healthy individuals.
Authors: Milton Packer; William T Abraham; Mandeep R Mehra; Clyde W Yancy; Christine E Lawless; Judith E Mitchell; Frank W Smart; Rachel Bijou; Christopher M O'Connor; Barry M Massie; Ileana L Pina; Barry H Greenberg; James B Young; Daniel P Fishbein; Paul J Hauptman; Robert C Bourge; John E Strobeck; Srinvivas Murali; Douglas Schocken; John R Teerlink; Wayne C Levy; Robin J Trupp; Marc A Silver Journal: J Am Coll Cardiol Date: 2006-05-15 Impact factor: 24.094
Authors: Nirav Y Raval; Pierre Squara; Michael Cleman; Kishore Yalamanchili; Michael Winklmaier; Daniel Burkhoff Journal: J Clin Monit Comput Date: 2008-03-14 Impact factor: 2.502