Trial Outcomes & Findings for Effect of Intradialytic Exercise on Left Ventricular Diastolic Function in Hemodialysis Patients (NCT NCT06584734)

The target population consisted on prevalent chronic kidney disease patients treated in the hemodialysis center at the National Institute of Cardiology between September 2023 and September 2024

Participants were screened for a baseline echocardiographic window adequate for diastolic function measurement and their physical ability to perform stationary cycling during hemodialysis. Patients were excluded if they experienced a major cardiovascular event or decompensated heart failure in the 3 months prior to enrollment

Of the 21 enrolled participants, questionnaire data were available and analyzable for 13 participants. Data from 8 participants were excluded due to incomplete or non-interpretable responses, limiting valid scoring of the instrument.

Classification of left ventricular diastolic function into ordinal grades based on the 2016 ASE/EACVI guidelines. Classification is determined by integrating E/A ratio, average E/e' ratio, indexed left atrial volume (LAVi), and tricuspid regurgitation (TR) velocity. Grade 1 (mild, impaired relaxation) is the least severe; Grade 2 (moderate, pseudonormal filling) represents intermediate severity; Grade 3 (severe, restrictive filling) is the most severe. Grading criteria: Grade 1 (mild - impaired relaxation): E/A \< 0.8, average E/e' ≤ 14, LAVi ≤ 34 ml/m², TR velocity ≤ 2.8 m/s; fewer than 2 positive criteria. Grade 2 (moderate - pseudonormal filling): E/A 0.8-2.0, with ≥ 2 of the following positive: average E/e' \> 14, LAVi \> 34 ml/m², TR velocity \> 2.8 m/s. Grade 3 (severe - restrictive filling): E/A \> 2.0, or E/A 0.8-2.0 with all three criteria positive.

Peak longitudinal deformation of the left atrium during the reservoir phase measured by 2D speckle tracking echocardiography. Expressed as a percentage (%). Higher values indicate better left atrial reservoir function and, indirectly, less elevation in left ventricular filling pressures.

Assessment of myocardial deformation using 2D speckle tracking echocardiography. Values are expressed as a negative percentage (%); more negative values indicate better longitudinal contraction (e.g., -17.4% is better than -15.5%)

Automated left ventricular ejection fraction (%), calculated using automated contour detection software applied to 2D echocardiographic images. Represents the proportion of blood ejected from the left ventricle with each heartbeat. Higher values indicate better left ventricular systolic function; values \>= 52% are considered within normal range.

Tricuspid annular plane systolic excursion (TAPSE), measured in millimeters (mm) by M-mode echocardiography at the lateral tricuspid annulus. Reflects right ventricular longitudinal systolic function. Higher values indicate better right ventricular function; values \>= 17 mm are considered within normal range.

Non-invasive estimate of left ventricular filling pressure calculated as the ratio of early diastolic mitral inflow velocity (E wave, pulsed-wave Doppler) to the average of septal and lateral mitral annular early diastolic velocities (e', tissue Doppler imaging). Higher values indicate elevated filling pressures.

Ratio of early diastolic (E wave) to late diastolic (A wave) mitral inflow velocities measured by pulsed-wave Doppler echocardiography with the sample volume placed at the mitral valve leaflet tips, apical four-chamber view. Reflects left ventricular relaxation and filling patterns.

Left atrial volume indexed to body surface area (ml/m\^2) measured by the biplane Simpson method using apical four-chamber and two-chamber views. Reflects left atrial structural remodeling as a marker of chronic elevation in left ventricular filling pressures. Lower values indicate less atrial remodeling and are associated with better diastolic function; values \<= 34 ml/m2 are within the normal range per ASE 2016 guidelines.

Peak tricuspid regurgitation velocity (cm/s) assessed by continuous-wave Doppler echocardiography, used to estimate right ventricular systolic pressure and pulmonary artery pressure per the 2016 ASE/EACVI diastolic function guidelines. Lower values are associated with lower estimated pulmonary pressures and less severe diastolic dysfunction; values \<= 2.8 m/s are within the normal range.

General Practice Physical Activity Questionnaire. Self-administered questionnaire for adults consisting of 3 questions assessing type and amount of physical activity at work, during leisure time, and usual walking pace. Classifies patients into 4 levels: Inactive, Moderately Inactive, Moderately Active, and Active. Higher activity levels represent better physical activity status; Active is the most favorable and Inactive is the least favorable category.

Total distance in meters (m) that a patient can quickly walk on a flat, hard surface in a period of 6 minutes based on the guidelines of the American and European Thoracic Societies by two medical interns, who are trained to perform the test. It assesses functional capacity and response to the exercise intervention. Greater distances indicate better functional exercise capacity.

Peak workload (maximal power output) is defined as the highest power output (in watts) achieved during a symptom-limited incremental CPET on a cycle ergometer, corresponding to the last fully completed workload stage or the highest workload maintained for ≥30 seconds. Higher values indicate greater maximal aerobic exercise capacity.

Power output (watts) achieved during a cardiopulmonary exercise test (CPET) at the point of the first ventilatory threshold (VT1) -- the exercise intensity above which ventilation begins to increase disproportionately to oxygen consumption. Higher values indicate greater aerobic exercise capacity and improved cardiovascular fitness.

Maximum rate of oxygen consumption (VO2 max) measured during incremental exercise on a cycle ergometer, expressed in milliliters per kilogram per minute (ml/kg/min). Reflects overall cardiorespiratory fitness and aerobic capacity. Higher values indicate better cardiovascular fitness; values \< 17.5 ml/kg/min in dialysis patients are associated with increased cardiovascular risk.

Left atrial reservoir strain assessed by 2D speckle tracking echocardiography at three study timepoints as a pre-specified sensitivity analysis. Expressed as percentage (%).

Automated left ventricular ejection fraction assessed by echocardiography using automated contour detection software at three study timepoints as a pre-specified sensitivity analysis. Expressed as percentage (%).

Ratio of early diastolic (E) to late diastolic (A) mitral inflow velocities measured by pulsed-wave Doppler echocardiography at three study timepoints as a pre-specified sensitivity analysis.

Left atrial volume indexed to body surface area (ml/m\^2) measured by biplane Simpson echocardiography at three study timepoints as a pre-specified sensitivity analysis.

Peak tricuspid regurgitation velocity (cm/s) assessed by continuous-wave Doppler echocardiography at three study timepoints as a pre-specified sensitivity analysis

Ratio of early mitral inflow velocity to the average mitral annular velocity (E/e') assessed at three study timepoints as part of the pre-specified echocardiographic sensitivity analysis. Higher values indicate elevated left ventricular filling pressures.