Clinical Significance of Using Stress Echocardiography for Cardiovascular Rehabilitation

Summary

Here, we present a protocol to measure cardiac function during exercise, using the stress echocardiography method in patients with heart failure. We then discuss the relevance of this method for clinicians and patients to develop its use in the clinical context.

Abstract

Studies performed in humans and animals using exercise have yielded many insights into cardiovascular physiology and mechanisms by which the heart, the myocardium, and the vessels respond to exercise stress. One of the clinical interests of stress echocardiography (SE) is to find slight dysfunctions that cannot be seen during routine exams at rest. The main steps of this SE protocol begin with patient preparation (e.g., hold caffeine, beta-blockers 24 h before SE, no contraindications) and a baseline assessment, including resting echocardiographic images (2D, Doppler, and optional strain imaging) in standard views (parasternal, apical, and subcostal). Then, the stress phase follows, using exercise on a dedicated bicycle with continuous monitoring of ECG, blood pressure, symptoms, and echocardiographic images. Immediately after peak stress, post-stress imaging is performed to rapidly acquire the same views, comparing wall motion, contractility, and Doppler-derived parameters to detect changes (e.g., ischemia, wall motion abnormalities, pressures). Another interest in measuring cardiovascular function during exercise is to better understand how the heart, the myocardium, and the vessels adapt in response to stress. SE also combines functional and imaging data that can improve heart failure phenotyping, and personalized treatment to improve patient care. To maximize the reliability of future studies using exercise, it is important to provide standardized methods allowing the measurement of cardiovascular function during exercise and to provide standardized exercise protocols. In this context, the present paper will focus on patients with heart failure. The objectives of the paper are to describe the stress echocardiography method and report the practical and clinical applications and discuss the relevance of this method for clinicians and patients.

Introduction

According to the World Health Organization (WHO), heart failure (HF) is defined as a complex syndrome in which the heart is unable to pump sufficient blood to meet the body's metabolic needs¹. This condition can result from systolic dysfunction, where the heart fails to contract properly, or diastolic dysfunction, where the heart does not fill adequately². HF is classified into two main categories: heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF)³. In HFrEF, the left ventricular ejection fraction (LVEF) is <40%, indicating decreased pumping capacity, while in HFpEF, the LVEF is normal or near-normal, but the heart exhibits increased stiffness, preventing adequate filling⁴. The methods commonly used to evaluate cardiac function include standard echocardiography, tissue Doppler imaging (TDI), and magnetic resonance imaging (MRI)⁵.

Standard echocardiography is a non-invasive technique that allows visualization of cardiac structures and real-time assessment of ventricular and valvular functions⁶. It uses ultrasound to create images of the heart, enabling observation of the cardiac wall movements, blood flow through the valves, and the size of the cardiac chambers⁷. Standard echocardiography is essential for diagnosing various cardiac conditions such as cardiomyopathies, valvular diseases, and congenital anomalies⁸.

TDI, an advanced echocardiographic modality, measures myocardial velocities, providing detailed information on diastolic and systolic function⁹. TDI is particularly useful for assessing myocardial relaxation and stiffness, as well as detecting subtle ventricular dysfunctions that may not be apparent on standard echocardiography⁵.

Cardiac MRI offers a precise evaluation of cardiac function, volumes, myocardial masses, and scar tissues¹⁰. This technique uses magnetic fields and radio waves to produce detailed images of the heart without using ionizing radiation¹¹. Cardiac MRI is considered the gold standard for volumetric and functional assessment of the heart¹². Additionally, it can identify the presence of fibrosis or myocardial scars, providing crucial information for treatment planning^13,14.

These evaluations are often performed at rest, which may not fully reveal potential cardiac dysfunctions¹⁵. For this reason, stress echocardiography (SE) was introduced as a crucial complementary method¹⁶. SE differs from rest echocardiography in its ability to evaluate the hemodynamic response of the heart to exertion. By simulating physical exercise or using pharmacological agents to induce cardiac stress, SE can uncover potential dysfunctions that remain invisible at rest¹⁵.

Exercise induction: During SE, the patient may be required to perform physical activity, such as walking or running on a treadmill, or pedaling on an ergometer bike¹⁷. Alternatively, medications like dobutamine or adenosine can be administered to increase heart rate and simulate exertion¹⁸. This approach evaluates the heart's ability to respond to increased demand for oxygen and nutrients, revealing functional and structural abnormalities not detectable at rest^19,20,21.

Hemodynamic measurements: SE provides a more complete view of cardiac function, allowing cardiologists to measure how cardiac output, volumes, and diameters (end-systolic and end-diastolic) adapt to exertion¹⁷. For example, it allows tracking changes in the diameter of cardiac chambers and measuring ejection fraction under stress²². This technique is particularly useful for detecting myocardial ischemia, dynamic valvular insufficiencies, and abnormal increases in intracardiac pressures²².

More precisely, exercise stress aims at targeting a heart rate ≥ 85% of age-predicted maximum. While pedaling on a semi-supine bicycle ergometer, SE allows the analysis of cardiac responses to exercise from rest to peak exercise and recovery following generally the Bruce protocol. Thus, SE offers the potential to detect ischemia and delayed abnormalities. However, key contraindications must be considered, including acute decompensated heart failure, severe aortic stenosis, or uncontrolled arrhythmias, while limitations such as poor acoustic windows or chronotropic incompetence may reduce test sensitivity. This approach balances comprehensive functional assessment with careful risk stratification in high-risk populations like heart failure patients.

By evaluating these parameters under stress, SE significantly improves clinical diagnosis by offering a more comprehensive understanding of heart behavior¹⁵. It helps identify patients at increased risk of cardiovascular events and tailor therapeutic strategies¹⁵.

For patients suffering from HF, SE offers the advantage of enabling more precise treatment tailored to the severity of their condition²². By accurately identifying cardiac dysfunctions, doctors can customize treatment and training programs, thereby improving quality of life and clinical outcomes¹⁶. The SE's ability to provide detailed information on the heart's response to exertion helps target therapeutic interventions better, reducing the risk of complications and repeated hospitalizations¹⁵.

The overall goals of this methodological article are to present the SE protocol, report on the practical and clinical applications of this technique in patients with HFrEF¹⁶ and discuss the clinical relevance of SE and present previous studies conducted in HF patients²². Stress echocardiography represents a powerful diagnostic tool that reveals cardiac dysfunctions not detectable at rest¹⁶. By providing a more complete view of the heart's response to exertion, it enhances clinical diagnosis and allows for more personalized treatments¹⁵. This article aims to demonstrate the importance of SE in the management of HF, particularly in patients with HFrEF, and to highlight its practical clinical applications²².

In addition, while the use of SE in HFrEF is well established, its methodological relevance to HFpEF and mildly reduced ejection fraction (HFmrEF) is also recognized²³. In these populations, SE can reveal impaired cardiac reserve and stress-induced elevations in left ventricular filling pressures (e.g.,via E/e′ ratio) and pulmonary artery systolic pressure, which may remain within normal limits at rest.

Thus, SE offers a reproducible and physiologically relevant methodology for unmasking latent cardiac dysfunction across the spectrum of heart failure phenotypes, with significant diagnostic and prognostic implications. Moreover, SE enables dynamic evaluation of systolic and diastolic function, myocardial strain, and contractile reserve, offering valuable insights into disease mechanisms and therapeutic responses in mice²⁴. Its ability to detect early or subtle impairments in cardiac performance makes SE a powerful tool in translational cardiovascular research, bridging experimental findings with clinical relevance. We hope that this method will be used routinely by clinicians in the future.

Protocol

The protocol described below follows the guidelines of the Université Paris Cité's human research ethics committee; written informed consent has been obtained from the patients involved.

Below is the fully detailed resting echocardiography methodology.

1. Patient preparation

1. Place the patient in a left lateral decubitus position for rest echocardiography and then install the patient on the semi-supine bicycle for SE.
2. Place the electrodes for accurate correlation with the cardiac cycle.

2. Image acquisition

1. Left Ventricle (LV)
   1. Measure the end-diastolic (EDD) and end-systolic (ESD) dimensions of the LV, as well as wall thickness (normal range: 0.6-1.0 cm). Analyze segmental motion to detect abnormalities such as hypokinesia.
      1. For 2D Mode Acquisition with a Parasternal Long Axis View (PLAX), select 2D mode by pressing the corresponding button. Use the trackball to optimize the image and obtain a clear view of the LV in PLAX.
      2. To measure End-Diastolic (EDD) and End-Systolic Dimensions (ESD), press Freeze when the LV is at maximal diastole. Measure the EDD by pressing Measure, select LV Measurements from the menu, use the trackball to place the cursors on the endocardial interfaces of the interventricular septum and the posterior wall, and validate the measurement by pressing Enter. Next, release Freeze, advance to maximal systole, then press Freeze again. Measure the ESD by placing the cursors similarly to measure the ESD and validate the measurement.
      3. To measure the wall thickness in diastole, use the 2D mode and select Wall Thickness from the measurement menu. Then, measure the thickness of the interventricular septum and the posterior (inferolateral) wall by placing cursors on the corresponding endocardial and epicardial limits, ensuring the measurements are within the range of 0.6 to 1.0 cm. Finally, validate the measurements.
      4. To analyze segmental Motion, use the 2D mode and observe the motion of the interventricular septum and posterior wall throughout the cardiac cycle, looking for abnormalities, such as hypokinesia, by noting any reduction in thickening or motion of these segments during systole.
      5. To proceed with the recording and verification, press Save to store all measurements and observations. Then, review the data through the Patient Data menu to ensure accuracy.
2. Mitral valve and aortic valve
   1. Observe the mobility and synchronization of the anterior and posterior leaflets. Confirm that the opening is wide and symmetrical without prolapse and tethering is seen. For aortic valve analyses, check for tricuspid configuration and cusp movements. Ensure complete opening in systole and closure in diastole.
   2. To analyze these valves, select 2D mode and position the probe in the PLAX view. To optimize the quality of the image, use the trackball for clear visualization of the aortic/mitral valve, fine-tune gain, depth, and focus.
   3. To observe the leaflets, select the 2D mode and observe the mobility of the anterior and posterior leaflets. Check also the synchronization of movements throughout the cardiac cycle.
      1. To detect the prolapse, use the zoom function for a detailed inspection; if necessary, press Zoom and select the area of interest using the trackball.
         NOTE: It is important to look for signs of prolapse, such as a leaflet moving beyond the aortic/mitral annular plane during systole.
      2. To switch to Apical Four-Chamber View, reposition the probe to obtain the apical four-chamber view and adjust the image using the trackball and adapt the gain and the zoom to visualize the four cavities of the heart into the image settings. Then, press freeze to capture key images and press save to save images and video. Alternatively, prepare a report of the observations using the report menu.
3. Aortic root
   1. To measure the diameter at the sino-tubular junction (normal range: 2.0-3.7 cm), select the 2D mode and position the transducer in the PLAX view. Use the trackball to optimize the image of the aortic root and adjust image settings (gain, depth, focus) for better clarity.
   2. Freeze the image when the aortic root is clearly visualized in diastole and press the measure button to select aortic dimensions. Place the first cursor at the exact point where the sinuses of Valsalva end and position the second cursor at the sino-tubular junction. To validate the measurement, press enter and record it by pressing the save button.
4. Left Atrium (LA)
   1. To measure the dimensions and volumes of the LA (normal anteroposterior diameter: <4.0 cm for men, <3.8 cm for women), select the 2D mode and position the probe in the PLAX view to obtain a clear view of the LA. Adjust the image using the trackball and fine-tune the gain and depth settings. To measure the anteroposterior diameter, press freeze at the end of systole, select measure, and choose LA measurements. Use the trackball to place the cursors on the anterior and posterior walls of the LA and confirm the measurement by pressing enter.
   2. To calculate the volume of the LA, switch to the apical four-chamber view and press freeze at the end of the systole. Select trace from the measure menu and trace the internal contour of the LA using the trackball. Confirm the calculation by pressing enter and save to record and store the measurements and images.
5. Parasternal short axis (PSAX) view
   1. To obtain this view, rotate the probe 90° from the PSAX view and point the probe index towards the left shoulder.
   2. To evaluate the mobility and thickness of the left ventricular papillary muscles (normal thickness: 0.6-1.0 cm), select 2D mode, position the probe to visualize the papillary muscles, and press freeze during diastole. Then, select measure | LV measurements from the menu. Use the trackball to place the cursors on the edges of the papillary muscle and confirm the measurement by pressing enter. To record the measurements, press save.
   3. To analyze the chordae tendineae and apical segments for movement abnormalities, select the 2D mode and position the probe in the apical four-chamber view. Adjust the image using the trackball for a clear visualization of the chordae tendineae connecting the papillary muscles to the mitral valve leaflets. For detailed analyses, use the zoom function and select the area of interest with the trackball. To confirm the images, press freeze and record it or the video clips; press save.
6. Right Ventricle (RV)
   1. To measure the RV EDD (<2.8 cm) and the free wall thickness (0.3-0.5 cm), select the 2D mode and position the probe in the apical four-chamber view.
   2. To measure the RV EDD, freeze the image at the end of the diastole, press measure, and select RV measurements from the menu. Adjust the depth to focus the image on RV. Then, use the trackball to position the cursors on the RV free and septal walls at the tricuspid annulus level and validate the measurement by pressing enter.
   3. To measure the RV free wall thickness, reposition the probe for a better view of the RV free wall. Freeze the image at the end of diastole and select RV wall thickness from the measurement menu. Position the cursors on the endocardial and epicardial boundaries of the RV free wall, validate the measurement by pressing enter, and record it by pressing save.
7. Right and Left Atria (RA and LA)
   1. To measure the dimensions and volumes of the right and left atria (LA volume index < 34 ml/m², RA width < 4.5 cm), select the 2D mode and position the probe in the apical four-chamber view and apical two-chamber view in biplane. Use the trackball to optimize the image for clear visualization of both atria.
   2. To measure the LA volume, freeze the image at end-systole, press measure, and select LA volume. Use the trackball to trace the internal contour of the LA, excluding the pulmonary veins and left atrial appendage after verifying that the LA volume index is <34 mL/m² Validate and save the measurement by pressing enter and save, respectively.
   3. To measure the RA dimensions, freeze the image at end-systole, press measure, and select RA dimensions. Use the trackball to position the cursors at the widest point of the RA width. Validate and save the measurement by pressing enter and save, respectively.
8. To measure LV dimensions (LV End-Diastolic Diameter [LVEDD]: 3.9-5.3 cm for women, 4.2-5.9 cm for men) and RV dimensions, and assess systolic and diastolic function (Ejection Fraction [EF]: 55-70%), activate the 2D mode, position the probe for Apical Four-Chamber View (A4C), and position it at the heart's apex (lower tip) by placing the probe index toward the patient's head. Use the trackball to visualize the center of cardiac chambers on the screen, and adjust the depth to include both LV and RV.
   1. To measure LV dimensions, freeze the image at end-diastole, press measure, and select LV measurements. Place the cursors for LVEDD as follows: upper Cursor on the endocardium of the interventricular septum and lower Cursor on the endocardium of the LV lateral wall. Validate the measurement by pressing enter.
   2. To measure the RV dimensions, freeze the image at end-diastole, press measure, and select RV measurements. Place the cursors for RVEDD as follows: upper cursor on the endocardium of the RV free wall and lower cursor on the endocardium of the interventricular septum. Validate the measurement by pressing enter.
   3. To evaluate LV systolic function, press Simpson's method (EF Biplane) and acquire the images in A4C view. Rotate the probe approximately 60° counterclockwise to obtain an Apical Two-Chamber View (A2C) and center the LV on the screen. Trace the endocardial contours at end-diastole and end-systole for both A4C and A2C views using the trackball. Wait for the device to calculate EF (normal range between 55% and 70%) automatically once contours are traced.
   4. To evaluate LV diastolic function, press PW Doppler and place the sample volume at the mitral valve leaflet tips. To record a Doppler spectrum, press update.
      1. To measure E and A waves, freeze the image and proceed to the measurement of the the peak velocity of the E wave, A wave, and E/A (confirm that it is >1). To record data, press update.
      2. Measure the E Wave deceleration time (normal range: 160-240 ms) using the Tissue Doppler Imaging (TDI). Activate the TDI by pressing TDI or Tissue Doppler and place the cursor on the mitral annulus at the septal and lateral walls. To record data, press update.
      3. To measure e', freeze the image and note the mean e' velocity. Confirm that the E/e' ratio is <8. To record data, press update.
9. To observe the motion of the tricuspid valve leaflets to detect abnormalities, position the probe to obtain the A4C, place it at the heart's apex, and turn the probe index toward the patient's head. Then, activate the 2D mode and use the trackball to place the cursor at the center of the tricuspid valve on the screen. Adjust the depth to include the tricuspid valve and adjacent structures. To capture images, press freeze and record it by pressing save.
10. To measure mitral flow to assess left ventricular diastolic function by calculating the E/A ratio (>1) and the E-wave deceleration time (normal range: 160-240 ms), position the probe for A4C, place it at the heart's apex, and turn the probe index toward the patient's head. Activate the Pulsed-Wave Doppler by pressing PW Doppler and place the sample volume at the mitral valve leaflets, just below the mitral annulus in the left ventricle. To record the Doppler Spectrum, press update to start recording the Doppler spectrum.
    NOTE: Measure E and A waves and E/A, E-Wave Deceleration Time as previously described (steps 2.8.4.1 and 2.8.4.2).
11. To measure Tricuspid Annular Plane Systolic Excursion (TAPSE) to assess the right ventricular systolic function (normal: >1.6 cm), position the probe for A4C, place it at the heart's apex, and turn the probe index toward the patient's head. Use the trackball to center all four chambers on the screen and adjust the depth to clearly visualize the tricuspid annulus. Then, activate the M-Mode, position the M-Mode cursor over the tricuspid annulus, at the junction between the right ventricle and the valvular annulus using the trackball, and press update to begin real-time recording of the tricuspid annulus motion. Once a complete cardiac cycle is recorded, press freeze to stop and hold the image, press measure, place the first cursor at the lowest point of the annulus motion (end-diastole) and the second cursor at the highest point of the annulus motion (end-systole), press validate to confirm the measurement, observe the TAPSE value, and press save to store the image and the TAPSE measurement.
12. Apical two-chamber (A2C) view
    1. To evaluate the basal, mid, and apical segments of the anterior and inferior walls of the LV for motion and myocardial thickness (normal range: 0.6-1.0 cm), activate the 2D mode, center the LV on the screen, including the apex and base using the trackball, and adjust the depth to include the full length of the LV. Position the focus at the level of the segments of interest (anterior and inferior walls - normal thickness: 0.6-1.0 cm).
13. To assess the size and function of the four cardiac chambers, position the probe under the xiphoid process (subcostal view), slightly to the right of the midline. Direct the probe index toward the patient's head at a 15-30° angle and activate the 2D mode. Center the four cardiac chambers on the screen and adjust the depth to include all cardiac structures. For RA and LA, assess the size, shape, and filling; for RV and LV, assess wall thickness, contractility, and valve motion; press save to store relevant images.
14. To measure the diameter (to be <2.1 cm) and collapsibility of the inferior vena cava, from the subcostal view, tilt the probe to the patient's right and slightly downward to align the IVC longitudinally. Adjust the depth and gain to obtain a clear image of the IVC and its junction with the right atrium, and activate the 2D mode and freeze image when the IVC is at its maximum diameter during expiration. Press measure and select IVC measurement; then, place the first cursor on the inner edge of the anterior IVC wall, 1-2 cm upstream of the right atrium and the second cursor on the inner edge of the posterior opposite wall. Press enter to validate the measurement.
    1. For the collapsibility of the inferior vena cava, into the same operating mode, instruct the patient to take a deep inspiration and observe the reduction in IVC diameter during inspiration. Collapsibility > 50% indicates normal right atrial pressure. Press save to store images and measurements.
       NOTE: Normal IVC (<2.1 cm) and collapsibility >50%: Low right atrial pressure (0-5 mmHg) and dilated IVC or collapsibility <50%: Elevated right atrial pressure (>10 mmHg).
15. To visualize the aortic arch and its main branches (brachiocephalic artery, left common carotid artery, left subclavian artery) to detect abnormalities such as coarctations, dilations, or congenital anomalies, place the probe in the suprasternal notch (depression above the sternum). Direct the probe index toward the spine (toward the back of the patient lying in the supine position with the neck slightly extended to facilitate access), activate the 2D mode, and center the aortic arch on the screen using the trackball. Adjust the depth to include the entire aortic arch and its branches, and identify the curvature of the ascending aorta transitioning into the descending aorta, the first branch visible arising from the aortic arch, the left common carotid artery, the second branch seen to the left of the brachiocephalic trunk, and the third branch, located more laterally. Then, press freeze when a representative image is captured and save to store the image.
16. Cardiac output evaluation
    1. Assess the cardiac output (normal range at rest: 4-8 L/min) in the PSLA view, using the apical five-chamber (A5C) or three-chamber (A3C) views at the LV outflow tract (LVOT). Activate the 2D mode, press PW Doppler, place the sample volume within the LVOT (just below the aortic valve), and record the velocity-time integral (VTI) of the blood flow through the LVOT during systole. To record the Doppler spectrum, press update and wait for the cardiac output (CO) to be calculated as follows:
       Cardiac output CO = SV (stroke volume) x HR (heart rate)
       Where SV = LVOT CSA × LVOT VTI and CSA = π × (LVOT/2)².
17. Specific measurements and parameters
    1. Estimate the LV systolic function by the EF using the Biplane Simpson's method (normal values 55-70%) and Global longitudinal strain (GLS) (normal: -20% to -22%)²⁵.
    2. Estimate the LV diastolic function by measuring the E/A ratio (> 1) and the E-wave deceleration time (160-240 ms), e' and E/e' ratio (< 8) using the pulsed Doppler on mitral annulus velocity and by the tricuspid regurgitation gradient using the continuous Doppler (normal values < 35 mmHg)²⁶.

3. Stress echocardiography methodology

1. Patient preparation and protocol
   1. Perform the SE before and after training 1-3 days after the cardiopulmonary testing, on a cycle ergometer in a semi-supine position and in a partial left decubitus position using the same ramp protocol (10 watts/min). Stop the exercise when the patient presents a respiratory exchange ratio > 1.05, exhaustion due to fatigue, or clinical symptoms like blood pressure or ECG abnormalities.
   2. Determine three main workloads (W): the W1 corresponding to rest, W2 to the first ventilatory threshold (VT1), and W3 to peak exercise.
   3. During the exercise tests, record the heart rate (HR), systolic (SBP), and diastolic (DBP) blood pressures at the beginning of each minute and at peak exercise.
   4. Measure gas exchange parameters breath by breath and average them every 15 s for minute ventilation (VE, L/min), O₂ consumption (VO₂, L/min), and CO₂ production (VCO₂, L/min) using a gas analyzer system. Determine peak oxygen consumption (VO₂peak) and VE/VCO₂ slope and calculate oxygen pulse (VO₂/HR) and HR reserve (HRR) (HRpeak - HRrest).
   5. Perform SE during the CPET and obtain images using anultrasound apparatus. Record cine loops from apical 4-chamber and PSAX views. Obtain two-dimensional grayscale harmonic images at a rate of 65-90 frames/s. Acquire images in cine loop format triggered to the QRS complex.
   6. Analyze all images offline and measure different parameters during SE such as: LV systolic function (LVEF (=EDV - ESV / EDV) x 100); LV stroke volume (SV) (=π x (LVOT diameter)² / 4) x VTI); CO (= HR x SV)), LV diastolic function (E wave, A wave, LV E/A and E/e' ratios), LV dimensions (LV EDV and ESV), LVOT diameter and subaortic velocity time integral (VTI) (measure 3-10 mm below the aortic annulus.
      NOTE: The arterio-venous oxygen difference (mLO₂/L) can also be calculated as follows: oxygen uptake/CO.
2. Contractile reserve and other measurements
   1. Assess other useful parameters during SE such as:
      1. Determine the LV Contractile Reserve by measuring the stress/rest ratio of LV elastance (SBP peak / LVESV peak) / (SBP rest / LVESV rest).
      2. Determine the RV systolic function by measuring by the S wave.
      3. Estimate the PASP from tricuspid regurgitation using the modified Bernoulli equation (ΔP = 4xV₂² where V₂ = maximum flow velocity across the aortic valve).
      4. Estimate the RV function by the peak RV S minus the rest RV S.
      5. Measure changes between rest and peak exercise of CO, LV E/e' ratio, RV S wave, PASP, and HRR.
         NOTE: For a more didactic description of resting echocardiography methodology, refer to the Supplemental File 1.

Results

Patients' characteristics and exercise capacity

The elements below represent examples of typical profiles of patients followed in the cardiac rehabilitation departments of the Corentin Celton and the Paris Saint Joseph hospitals.

Mr. B: 71 years old, New York Heart Association (NYHA): 2, ejection fraction: 37%
Dilated cardiomyopathy + Cardiac Resynchronization Therapy
Exercise test: 70 watts, Peak of VO₂ 14.9 mL·kg^-1·mi...

Discussion

The findings from this study underscore the importance and utility of the SE in the comprehensive evaluation of patients with HFrEF. By employing a combination of resting echocardiography and SE, this study provides insights into the hemodynamic and functional changes that occur under stress conditions, which are often not apparent during rest.

Diagnostic value of stress echocardiography
One of the key advantages of SE over resting echocardiography is its ability to reve...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
CPX Vyntus	Vyvaire Medical	N/A	Respiratory gas exchange analyzer for cardiopulmonary exercise testing
EchoPac PC-SW 113	GE Healthcare	N/A	Software dedicated to visualize and analyze for cardiac ultrasound data
SanaBike  1.01	Ergosana - Schiller group	N/A	Bicycle ergometer
Vivid 9 Dimension	GE Healthcare	N/A	Echocardiograph