Zafeiris Louvaris1,2,3, Stavroula Spetsioti2, Vasileios Andrianopoulos4, Nikolaos Chynkiamis2,5, Helmut Habazettl6,7, Harrieth Wagner8, Spyros Zakynthinos2, Peter D Wagner8, Ioannis Vogiatzis2,3,5. 1. Faculty of Movement and Rehabilitation Sciences, Division of Respiratory Rehabilitation, Department Rehabilitation Sciences KU Leuven, University Hospitals Leuven, Leuven, Belgium. 2. 1st Department of Critical Care Medicine and Pulmonary Services, GP Livanos and M Simou Laboratories, Medical School of Athens University, Evangelismos Hospital, Athens, Greece. 3. Department of Physical Education and Sports Sciences, National and Kapodistrian University of Athens, Athens, Greece. 4. Institute for Pulmonary Rehabilitation Research, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany. 5. Department of Sport, Exercise and Rehabilitation, Faculty of Health and Life Sciences, Northumbria University, Newcastle, United Kingdom. 6. Institute of Physiology, Charite-University Medicine Berlin, Corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany. 7. Institute of Anesthesiology, German Heart Institute Berlin, Berlin, Germany. 8. Department of Medicine, University of California San Diego, La Jolla, California.
Abstract
INTRODUCTION: Impedance cardiography (IC) derived from morphological analysis of the thoracic impedance signal is now commonly used for noninvasive assessment of cardiac output (CO) at rest and during exercise. However, in Chronic Obstructive Pulmonary Disease (COPD), conflicting findings put its accuracy into question. OBJECTIVES: We therefore compared concurrent CO measurements captured by IC (PhysioFlow: COIC ) and by the indocyanine green dye dilution method (CODD ) in patients with COPD. METHODS: Fifty paired CO measurements were concurrently obtained using the two methods from 10 patients (FEV1 : 50.5 ± 17.5% predicted) at rest and during cycling at 25%, 50%, 75% and 100% peak work rate. RESULTS: From rest to peak exercise COIC and CODD were strongly correlated (r = 0.986, P < 0.001). The mean absolute and percentage differences between COIC and CODD were 1.08 L/min (limits of agreement (LoA): 0.05-2.11 L/min) and 18 ± 2%, respectively, with IC yielding systematically higher values. Bland-Altman analysis indicated that during exercise only 7 of the 50 paired measurements differed by more than 20%. When data were expressed as changes from rest, correlations and agreement between the two methods remained strong over the entire exercise range (r = 0.974, P < 0.001, with no significant difference: 0.19 L/min; LoA: -0.76 to 1.15 L/min). Oxygen uptake (VO2 ) and CODD were linearly related: r = 0.893 (P < 0.001), CODD = 5.94 × VO2 + 2.27 L/min. Similar results were obtained for VO2 and COIC (r = 0.885, P < 0.001, COIC = 6.00 × VO2 + 3.30 L/min). CONCLUSIONS: These findings suggest that IC provides an acceptable CO measurement from rest to peak cycling exercise in patients with COPD.
INTRODUCTION: Impedance cardiography (IC) derived from morphological analysis of the thoracic impedance signal is now commonly used for noninvasive assessment of cardiac output (CO) at rest and during exercise. However, in Chronic Obstructive Pulmonary Disease (COPD), conflicting findings put its accuracy into question. OBJECTIVES: We therefore compared concurrent CO measurements captured by IC (PhysioFlow: COIC ) and by the indocyanine green dye dilution method (CODD ) in patients with COPD. METHODS: Fifty paired CO measurements were concurrently obtained using the two methods from 10 patients (FEV1 : 50.5 ± 17.5% predicted) at rest and during cycling at 25%, 50%, 75% and 100% peak work rate. RESULTS: From rest to peak exercise COIC and CODD were strongly correlated (r = 0.986, P < 0.001). The mean absolute and percentage differences between COIC and CODD were 1.08 L/min (limits of agreement (LoA): 0.05-2.11 L/min) and 18 ± 2%, respectively, with IC yielding systematically higher values. Bland-Altman analysis indicated that during exercise only 7 of the 50 paired measurements differed by more than 20%. When data were expressed as changes from rest, correlations and agreement between the two methods remained strong over the entire exercise range (r = 0.974, P < 0.001, with no significant difference: 0.19 L/min; LoA: -0.76 to 1.15 L/min). Oxygen uptake (VO2 ) and CODD were linearly related: r = 0.893 (P < 0.001), CODD = 5.94 × VO2 + 2.27 L/min. Similar results were obtained for VO2 and COIC (r = 0.885, P < 0.001, COIC = 6.00 × VO2 + 3.30 L/min). CONCLUSIONS: These findings suggest that IC provides an acceptable CO measurement from rest to peak cycling exercise in patients with COPD.
Authors: Łukasz Lewicki; Katarzyna Kosmalska; Sebastian Liedtke; Maciej Karwowski; Janusz Siebert; Robert Sabiniewicz; Jakub Kiedrzyn; Adrian Kot; Marek Szołkiewicz Journal: Cardiol J Date: 2020-11-03 Impact factor: 2.737
Authors: Lukasz Lewicki; Marta Fijalkowska; Maciej Karwowski; Konrad Siebert; Grzegorz Redlarski; Aleksander Palkowski; Radoslaw Targonski; Janusz Siebert Journal: Cardiol J Date: 2019-10-23 Impact factor: 2.737