Impedance cardiography applied to maximal arm cranking exercise: a matter of sampling and processing strategy
| Autor: | Marc Francaux, Daniel Theisen, Xavier Sturbois, T Daniel, Jacques Michotte de Welle |
|---|---|
| Přispěvatelé: | UCL - MD/IEPR - Institut d'éducation physique et de réadaptation |
| Rok vydání: | 1998 |
| Předmět: |
Adult
Male medicine.medical_specialty Cardiac output Signal conditioning Physical Therapy Sports Therapy and Rehabilitation Cardiography Impedance Ensemble-averaging Sampling (signal processing) Internal medicine Heart rate medicine Central hemodynamics Humans Orthopedics and Sports Medicine Cardiac Output Exercise End-systolic volume Mathematics medicine.diagnostic_test Hemodynamics Stroke Volume Stroke volume Surgery Impedance cardiography Time derivative Breathing Cardiology Artifacts |
| Zdroj: | Medicine and Science in Sports and Exercise, Vol. 30, no. 8, p. 1321-1327 (1998) |
| ISSN: | 0195-9131 |
| Popis: | PURPOSE: A new ensemble-averaging (EA) approach was developed with the goal of investigating central hemodynamics by transthoracic impedance cardiography during maximal arm cranking. This EA procedure of the first time derivative of impedance changes (dZ/dt) over several cardiac cycles differs from previously reported techniques with respect to cycle selection strategy, according to fixed criteria, and processing methods. METHODS: First, the primary elements of the Kubicek stroke volume (SV) formula, as determined by EA, were compared with the values determined by the standard hand-processing (HP) method over a large range of cardiac outputs. RESULTS: Results showed a very high reliability for ventricular ejection time (r = 0.996), (dZ/dt)min (r = 0.995), SV (r = 0.977), and heart rate (r = 0.999). Second, the EA procedure was applied to six subjects performing a continuous, multistage arm cranking test to volitional fatigue. The present technique allowed for an effective filtering of movement and breathing artifacts of the original signal. Thus, interpretation of the dZ/dt wave form was convenient, even at maximal arm cranking power outputs up to 120 W. Stroke volume ranged from 63.83 to 127.18 mL.beat-1, showing no significant variations with oxygen consumption. Cardiac output increased linearly with oxygen uptake, reaching a mean maximal value of 16 L.min-1. CONCLUSION: The present procedure opens a new field of application to impedance cardiography, permitting to measure cardiac output during maximal arm cranking exercise. |
| Databáze: | OpenAIRE |
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