Cardiopulmonary Exercise Testing Parameters' Variability in Hemodialysis Patients.

This is an observational study with a cross-over design performed in the Department of Nephrology and the Third Department of Cardiology in Hippokration Hospital of Thessaloniki in Greece. For the purposes of this study, hemodialysis patients fulfilling the inclusion/exclusion criteria, as well as controls without CKD, were invited to participate. All included patients signed a written informed consent form. The study protocol was approved by the Ethics Committee of the School of Medicine, Aristotle University of Thessaloniki. All procedures and evaluations are performed according to the Declaration of Helsinki 2013 Amendment. Baseline evaluation includes the recording of demographics and anthropometric characteristics, medical history, concomitant medications and dialysis-related parameters, as well as physical examination and venous blood sampling for routine laboratory tests. Hemodialysis patients will be evaluated at two time points (at the end of the long and at the end of the short interdialytic interval), while controls at one time point. All the participants will undergo spirometry, CPET, cardiac ultrasound, lung ultrasound and bioelectrical impedance analysis.