PrehabilitationPREPA-STERNCT07893184
Feasibility of Physical Prehabilitation for High-Risk Patients Undergoing Cardiac Surgery Via Sternotomy
A study testing Physical Prehabilitation Intervention in people with Prehabilitation and Cardiac Surgery, run by Maastricht University Medical Center at 1 site in Netherlands.
Trial summary
Rationale Cardiac surgery via median sternotomy carries an elevated risk of postoperative complications and delayed functional recovery. Preoperative physical therapy aims to reduce the incidence and severity of postoperative adverse outcomes and to accelerate functional recovery. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Prehabilitation, Cardiac Surgery, Risk Assesment
- What is being tested?
- Physical Prehabilitation Intervention
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteNetherlands
- Study dates
- 17 Sep 2026to 30 Aug 2027
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age: ≥18 years.
- Surgical procedure: Scheduled to undergo elective CABG or AVR via median sternotomy;
- Allowed concomitant procedures: Isolated procedures or in combination with concomitant procedures (i.e., MAZE, Pulmonary Vein Isolation (PVI), clip Left Arterial Appendage (LAA)).
- High risk classification: Classified as High-Risk for postoperative complications or delayed functional recovery, identified via a two-stage screening process:
- Elevated Surgical Risk (Stage 1): Defined by a EuroSCORE II ≥1.33.
- Multivariable Confirmation (Stage 2): Further screening using the prediction model that integrates EuroSCORE II, cardiorespiratory fitness (FITmáx), frailty (EFS), and BMI.
- Waiting time: Expected waiting time > 4 weeks before surgery
- Communication: Able to understand and communicate in Dutch.
Who cannot join
- Procedure-related: Scheduled for combined CABG and AVR, or combined with MVP and/or TVP, or combined with aortic aneurysm repair
- Medical conditions, as described in the electronic medical record (EMR):
- Patients with a known Ascending Aorta Diameter (AAD) >45mm or any patient with an AAD > 40mm if they have an associated high-risk condition, including a known genetic connective tissue disorder or a history of aortic dissection.
- Recent acute coronary syndrome (< 3 weeks)
- Recent inflammatory myo-pericardial syndrome (< 1 month after remission) as recommended in the ESC Guidelines for the management of myo- and peri-carditis
- Conduction disturbances and/or arrhythmias with pacemaker (PM) or Implant-able Cardioverter Defibrillator (ICD) indication without a device implanted yet.
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- Decompensated heart failure or cardiomyopathy contraindicating exercise.
- Atrial fibrillation or other tachyarrhythmias with resting heart rate >120 bpm.
- Exercise and functional limitations, as described in the EMR:
- Left main coronary artery stenosis >80%
- History of frequent exercise-induced syncope's in Aortic valve Stenosis (AoS) and Aortic valve Insufficiency (AoI) patients
- Physical impairments that makes it impossible to complete the assessments and the prehabilitation program, as determined by an experienced physiother-apist.
- Cognitive impairment (e.g. dementia) that would impede understanding of study procedures, informed consent, or study questionnaires described by the medical specialist in the EMR.
- Incapacitated subjects as reported by the attending medical specialist in the medical record. (When any doubt arises, the patient will not be considered eligible).
- Exercise safety issues during the CPET at baseline measurement
- Serious-exercise induced ischemia
- Serious exercise-induced (supra-)ventricular arrhythmias
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Netherlands1 site
Maastricht University Medical Center
Maastricht, Limburg, 6229HX
About this study
Official title: Feasibility of a Physical Prehabilitation Programme for Patients at High Risk of In-Hospital Complications and Delayed Functional Recovery Awaiting Elective CABG or AVR Surgery Via Sternotomy: PREPA-STER
Rationale Cardiac surgery via median sternotomy carries an elevated risk of postoperative complications and delayed functional recovery. Preoperative physical therapy aims to reduce the incidence and severity of postoperative adverse outcomes and to accelerate functional recovery. However, current evidence on prehabilitation is inconsistent due to methodological heterogeneity. This study addresses the limitations of previous studies in four ways. First, a validated preoperative prediction model is used to select patients at high risk of in-hospital postoperative complications and delayed functional recovery. Second, a Cardiopulmonary Exercise Test (CPET) is performed at baseline to guide safe and effective intensity prescription. Third, as different patient populations are expected to benefit from different training programs, the prehabilitation program is tailored to the surgical indication: patients undergoing coronary artery bypass grafting (CABG) receive high-intensity interval training (HIIT), and patients undergoing aortic valve replacement (AVR) receive moderate continuous training. Fourth, physical activity and self-management are promoted by using a wearable physical activity monitor and Shared Decision-Making (SDM) to stimulate and track daily physical activity.
Primary Objective To investigate the feasibility of a personalized, procedure-specific prehabilitation program (four to six weeks) for high-risk patients scheduled for elective cardiac surgery via sternotomy, with respect to recruitment, adherence, drop-out, safety, and acceptance. The program consists of two physiotherapist-supervised group training sessions per week, promotion of physical activity, and unsupervised home-based exercise.
Read more
Secondary Objective To provide a preliminary evaluation of participant responses to the intervention, focusing on changes in cardiorespiratory fitness (WRpeak), peripheral muscle strength (1RM), inspiratory muscle strength (MIP), physical activity (time spent active per day), and health-related quality of life (SF-36).
Study design A prospective, single-center, longitudinal, mixed-methods pilot study conducted at Maastricht University Medical Center (MUMC+).
Study population High-risk patients (n=24), defined by EuroSCORE II, who are scheduled for elective cardiac surgery via sternotomy (CABG or AVR).
Main study parameters/endpoints The primary endpoint is the feasibility of the prehabilitation intervention with respect to recruitment, adherence, drop-out, safety, and acceptance.
Burden Participation involves a structured time commitment with clinic and home components. Total supervised clinic time is estimated at 11-15 hours, covering two baseline assessments, 8-12 training sessions, and the final evaluation and interview. Total time at home is estimated at 16.5-19 hours, covering daily diary completion and unsupervised home exercises. These ranges depend on the patient's time to surgery.
Risks and mitigation The risk of acute cardiac events during exercise is elevated in this high-risk population. This risk is mitigated by strict adherence to NVVC/MUMC+ absolute stop criteria, continuous medical supervision during all testing and training sessions, and individualized intensity prescription based on CPET. The risk is considered acceptable in relation to the scientific value of studying this specific high-risk cohort, which makes the study group-related.
Benefit and group relatedness Direct clinical benefit cannot be guaranteed, as this is a feasibility study. However, patients receive an intensive, personalized prehabilitation program that is designed to reduce the incidence and severity of postoperative adverse outcomes.
Read the detailed description
Cardiac surgery performed via median sternotomy is associated with a substantial risk of postoperative complications and delayed functional recovery. Preoperative physical therapy has been proposed as a strategy to optimize patients' physiological reserve before surgery and to improve postoperative outcomes. Although interest in prehabilitation for patients awaiting cardiac surgery has grown over the past decade, current evidence remains inconclusive due to several methodological limitations in the literature.
Addressing Methodological Gaps
The proposed study addresses four critical limitations of previous research:
- Lack of objective risk stratification Most studies investigating prehabilitation have enrolled patients awaiting cardiac surgery without accounting for individual surgical risk, preoperative physical fitness, or frailty. These factors are known to independently predict adverse postoperative outcomes. Few studies to date have attempted to target "high-risk" patients, and those that did relied on general selection criteria (e.g., age >65 years, sedentary behavior, or clinical frailty). Crucially, none have used a validated prediction model to objectively identify the patients most likely to benefit. The most recently published randomized controlled trial, by López-Hernández et al., recommended that future research focus on improving risk stratification and identifying subgroups most likely to benefit. The investigators hypothesize that preoperative screening is needed to identify patients truly in need of prehabilitation, so that the intervention can be targeted to those most likely to gain clinical benefit. This pilot study directly addresses this primary gap. To address this limitation, the investigators recently developed and internally validated prediction models that classify patients as high- or low-risk for postoperative in-hospital complications and delayed recovery of physical functioning. The classification consists of a two-stage screening process. Patients with an elevated surgical risk (measured by the EuroSCORE II) undergo further screening with a multivariable prediction model. This model integrates surgical risk (EuroSCORE II), cardiorespiratory fitness (FITmáx), and frailty (Edmonton Frail Scale, EFS). The investigators hypothesize that prehabilitation is particularly beneficial for patients classified as high-risk by this model, ensuring that specialized care is delivered to those most in need.
- Suboptimal cardiorespiratory fitness assessment The majority of previous studies performed suboptimal baseline testing of cardiorespiratory fitness, resulting in insufficient exercise intensity during the prehabilitation period. Most trials prescribed training intensities based on submaximal tests such as the six-minute walk test (6MWT) or formula-based heart rate estimates. Both lack the precision to accurately quantify cardiorespiratory fitness and to guide an appropriate exercise prescription. Consequently, it remains unknown whether these patients received an adequate training stimulus. Only two studies have used Cardiopulmonary Exercise Testing (CPET), the gold standard for quantifying cardiorespiratory fitness and guiding individualized training intensity. Steinmetz et al. administered CPET-guided endurance training (2 × 10 minutes per session), whereas López-Hernández et al. applied a CPET-guided interval training protocol consisting of 2-minute high-intensity and 3-minute low-intensity intervals. Although both studies reported improvements in 6MWT distance, only the latter showed significant gains in maximal oxygen uptake (VO2max), suggesting that training modality and intensity are critical determinants of the physiological response. To address this second limitation, the study therefore includes a baseline CPET with two explicit goals: first, to ensure that the chosen training intensities provide an adequate training stimulus, and second, to ensure that these intensities are safe.
- Patient heterogeneity and uniform protocols Patients undergoing cardiac surgery form a heterogeneous population, differing substantially in underlying cardiac disease and planned surgical procedure. Previous prehabilitation studies have largely used a single, uniform preoperative training protocol, irrespective of the underlying disease or anticipated surgery. The investigators hypothesize, however, that the training program must be adapted to the underlying cardiac disease. Patients undergoing Coronary Artery Bypass Grafting (CABG) and Aortic Valve Replacement (AVR), for instance, differ significantly in cardiovascular pathophysiology and hemodynamic responses to exercise. Patients awaiting CABG typically present with coronary artery disease and may tolerate high-intensity interval training (HIIT), whereas patients awaiting AVR often exhibit fixed cardiac output and are potentially at higher risk during peak exertion. Procedure-specific training protocols and stratified analyses are therefore warranted. To address this third limitation, and given that HIIT produces greater improvements in cardiorespiratory fitness than moderate-intensity continuous training (MICT), the study proposes CPET-guided, procedure-specific training: HIIT for CABG patients and MICT for AVR patients.
- Inadequate monitoring of daily physical activity
A poor preoperative physical activity level is another known risk factor for adverse postoperative outcomes after cardiac surgery. Many previous prehabilitation trials either did not systematically monitor and stimulate daily physical activity (PA) or relied on subjective self-report questionnaires with limited reliability. This methodological gap resulted in inadequate promotion and objective monitoring of PA in daily life outside of supervised sessions.
To address this fourth limitation, and to enhance self-management and adherence, the program integrates validated, objective PA monitoring using a wearable physical activity monitor (accelerometer). To promote sustained PA behavior, objective feedback is coupled with individualized goal setting guided by Shared Decision-Making (SDM) between patient and physiotherapist. This strategy ensures that feedback is precise and patient-aligned, which is crucial for sustained behavioral change.
Novel elements
To address these gaps, the proposed study introduces four novel elements:
- Delivering physical prehabilitation to patients classified as high-risk for postoperative complications and delayed recovery of physical functioning.
- Prescribing individualized training intensities based on CPET.
- Targeting two homogeneous patient populations, each receiving a procedure-specific training program.
- Incorporating objective physical activity monitoring and Shared Decision-Making to promote self-management and improve physical activity behavior.
- Conditions
- Prehabilitation, Cardiac Surgery, Risk Assesment, Aortic Valve, Coronary Artery Bypass Graft, Training
- Being tested
- Physical Prehabilitation Intervention
- Keywords
- Prehabilitation, Perioperative care, Cardiac surgery, CABG, AVR, Training intervention, Promotion of physical activity, Interval training, CPET, Preoperative exercise, preoperative training
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Physical Prehabilitation InterventionBehavioural
Also called Preoperative physical exercise, Prehabilitation
All study participants will undergo elective CABG or AVR within approximately five weeks or more following baseline assessment. The preoperative physical inter-vention will span a minimum of four to a maximum of six weeks (which means that they minimally participated in 8 to maximal 12 supervised training sessions) and consists of: • Two physiotherapist-supervised group training sessions per week consisting of: 1.Cardiorespiratory Fitness Training (based on CPET): CABG follow interval training; AVR follow continue training; 2.Peripheral Muscle Strength Training; 3.Inspiratory Muscle Strength Training (on indication); • Promotion of physical activity using wearable physical activity monitoring and goal-setting tailored to the individual's capacity and preferences.• Unsupervised home-based exercise (e.g., walking or cycling, strength exercises) tailored to the individual's capacity and preferences.
| Study group | Role | What they receive |
|---|---|---|
| High risk patients awaiting Coronary Artery Bypass Grafting or Aortic Valve Replacement | Experimental | Elective patients awaiting cardiac surgery via sternotomy (CABG or AVR) and are considerd through a two stage screening proces as high risk for in-hospital complications or delayed recovery of physical functioning.
two-stage screening process:
* Elevated Surgical Risk (Stage 1): Defined by a EuroSCORE II ≥1.33.
* Multivariable Confirmation (Stage 2): Further screening using the prediction model that integrates EuroSCORE II, cardiorespiratory fitness (FITmáx), frailty (EFS), and BMI. Receives: Behavioral: Physical Prehabilitation Intervention |
What is being measured
The primary outcome is the main question the study is designed to answer.
Recruitment - Recruitment rate
Number of included patients within the study period (n,%)
Measured: Week 0
Recruitment (Ineligibility rate due to CPET safety criteria
Number of patients withdrawn due to safety criteria (n,%)
Measured: Week 0
Adherence - Attendance rate for physiotherapist-supervised groups sessions
Number of attended sessions / total number of planned sessions (n,%)
Measured: Week 0-4~6
Adherence rate - Exercise Relative Dose Intensity ExRDI cardiorespiratory training (%)
ExRDI cardiorespiratory training = completed exercise dose intensity / prescribed exercise dose intensity.
Interval training (CABG) • Completed = Σ (completed work-interval duration [min] × completed work rate [WR]). • Prescribed = Σ (prescribed work-interval duration [min] × prescribed work rate [WR]).
Continuous training (AVR) • Completed = total completed duration [min] × completed work rate [WR].
- Prescribed = total prescribed duration [min] × prescribed work rate [WR]. ExRDI cardiorespiratory training is calculated for each participant individually, cumulative for all training sessions; and cumulative for all participants.
Measured: Week 0-4~6
Adherence rate - EXRDI peripheral strength training (%)
ExRDI peripheral strength training = completed exercise dose intensity / prescribed exercise dose intensity.
- Completed = completed weight [kg] × sets [N] × repetitions [N] per exercise.
- Prescribed = prescribed weight [kg] × sets [N] × repetitions [N] per exercise.
ExRDI peripheral strength training is calculated per participant per training session for each exercise and for all four exercises cumulative. And cumulative for all training sessions; and cumulative for all participants.
Measured: Week 0-4~6
Adherence rate - ErXDI inspiratory strength training (%)
ExRDI inspiratory strength training = completed exercise dose intensity / prescribed exercise dose intensity.
- Completed volume = completed resistance × sets [N] × repetitions [N].
- Prescribed volume = prescribed resistance × sets [N] × repetitions [N]. ExRDI inspiratory strength training will be calculated once weekly for each participant during the supervised training session. The weekly value will be accumulated across all supervised sessions and aggregated across participants.
For unsupervised inspiratory strength training, diary entries will be reviewed with the participant during the weekly supervised session. Patients will record the number of sets and repetitions performed each day, from which the completed exercise dose intensity will be derived. Prescribed volumes will be based on the individual's target resistance, sets, and repetitions for that week.
Supervised and unsupervised ExRDI values will be calculated and analyzed separately.
Measured: Week 0-4~6
Adherence - ExRDI Physical activity and unsupervised home-based exercises (%)
ExRDI physical activity and unsupervised home-based exerises = completed physical activity volume / prescribed physical activity volume.
- Completed volume = PAM measured activity (min/day)
- Prescribed volume = goal activity (min/day) ExRDI physical activity and unsupervised home-based exercises is calculated and evaluated per participant in the week during supervised training session. And cumulative for all weeks; and cumulative for all participants.
Measured: Week 0-4~6
Reasons for not having executed a training session as intended
Reasons for not having executed a training session as intended (e.g., low saturation, high blood pressure, the intended training intensity could not be sustained, tiredness, etc.)
Measured: Week 0-4~6
Reasons for not having executed a training session as intended stratified by trainings type
Reasons for not having executed a training session as intended (e.g., low saturation, high blood pressure, the intended training intensity could not be sustained, tiredness, etc.)
Measured: Week 0-4~6
Drop-out rate (%)
Number of participants who dropped out divided by the total number of participants
Measured: Week 0-4~6
Reasons for drop-out
Reasons for drop-out
Measured: Week 0-4~6
Acceptance - Experiences with the physical prehabilitation intervention
Patient-reported experiences with the prehabilitation program (semi-structured interviews).
Measured: Evaluation (after the whole training intervention).
Acceptance - Suitability of the physical prehabilitation intervention and study procedures
Patient-perceived suitability of the intervention and study procedures (semi-structured interviews).
Measured: Evaluation (after the whole training intervention).
Acceptance - Barriers and enablers regarding participation in the study
Patient-perceived barriers and facilitators to participation (semi-structured interviews).
Measured: Evaluation (after the whole training intervention).
Secondary outcomes (8)
Safety - Serious adverse events
A serious adverse event (n, %) is any untoward medical occurrence or effect that
- results in death;
- is life threatening (at the time of the event);
- requires hospitalization or prolongation of existing inpatients' hospitalization;
- results in persistent or significant disability or incapacity;
- is a congenital anomaly or birth defect; or
- any other important medical event that did not result in any of the outcomes listed above due to medical or surgical intervention but could have been based upon appropriate judgement by the investigator.
An elective hospital admission will not be considered as a serious adverse event.
In addition, within the context of this study, events such as (near-)collapse, chest pain, palpitations, or the use of emergency medication will be classified as SAEs if they meet the criteria outlined above (e.g., leading to EHH evaluation, hospitalization, or acute medical intervention).
Measured: From baseline to three month after surgery
Safety - Study related adverse events
The following events are considered potentially study-related adverse events (n,%) when occurring during or in temporal relation to the intervention:
- early termination of the training, because of the occurrence of one of the subjective or objective termination criteria (as described in section 5.1)
- (near-)collapse
- severe muscle pain lasting >2 days
- dizziness
- severe nausea
- palpitations or chest pain during exertion
- administration of pre-defined medication as needed (pro re nata, PRN) (e.g., Nitroglycerin) for acute symptoms arising during or immediately following the intervention.
Temporal classification rule:
- Events occurring during or within 1 hour after a training session are considered directly intervention-related unless proven otherwise.
- Events occurring more than 1 hour after the intervention are assessed on a case-by-case basis by the responsible physician, taking into account clinical context, temporal relationship, and alternative explanations.
Measured: From baseline to three month after surgery
Preliminary evaluation of changes in cardiorespiratory fitness
- WRpeak (W/kg) as determined by the Steep Ramp Test (SRT)
- Estimated VO2max (ml/kg/min) determined by FitMáx.
Measured: Baseline (Week 0) and evaluation (after the whole training intervention).
Preliminary evaluation of changes in peripheral muscle strength
-8-10-repetition maximum (8-10-RM, kg) determined indirectly via validated submaximal RM tests on leg press, chest press, leg extension, and vertical traction equipment.
Measured: Baseline (Week 0) and evaluation (after the whole training intervention).
Preliminary evaluation of changes in inspiratory muscle strength
-Maximum Inspiratory Pressure (MIP) (cmH2O)
Measured: Baseline (Week 0) and evaluation (after the whole training intervention).
Physical activity behaviour and home based exercise program
Physical activity is measured objectively using the ankle-worn PAM AM500 3-axis accel-erometer (min/day)
Measured: Continuously during intervention.
Postoperative in-hospital complications
Data extraction of usual care data for Nederlandse Hart Regristratie (NHR). (n,%)
Measured: After hospitalization/ discharge
Postoperative recovery of functioning
Data extraction of usual care data modified Iowa Level of Assistance Scale (mILAS) daily assessments by a physiotherapist (days til independence)
Measured: After hospitalization/ discharge
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Oct 2026
- Study start17 Sep 2026
- Primary completion30 Jun 2027 (estimated)
- Study completion30 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (6)Papers the sponsor has linked to this study.
- Other trials for PrehabilitationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Pilot - Feasibility study
- Masking
- None (open label)
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Maastricht University Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07893184
- Sponsor's protocol ID
- NL011105-304211
- Acronym
- PREPA-STER
- Status last verified
- Oct 2026
- First submitted
- 31 Dec 2025
- Last updated
- 23 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Individual Participant Data (IPD) will be shared upon reasonable request. Requests will be reviewed individually.
Publications
Marmelo F, Rocha V, Moreira-Goncalves D. The impact of prehabilitation on post-surgical complications in patients undergoing non-urgent cardiovascular surgical intervention: Systematic review and meta-analysis. Eur J Prev Cardiol. 2018 Mar;25(4):404-417. doi: 10.1177/2047487317752373. Epub 2018 Jan 17.
PubMed 29338307Steinmetz C, Bjarnason-Wehrens B, Walther T, Schaffland TF, Walther C. Efficacy of Prehabilitation Before Cardiac Surgery: A Systematic Review and Meta-analysis. Am J Phys Med Rehabil. 2023 Apr 1;102(4):323-330. doi: 10.1097/PHM.0000000000002097. Epub 2022 Sep 23.
PubMed 36149383Lopez-Hernandez A, Gimeno-Santos E, Navarro-Ripoll R, Arguis MJ, Lopez-Baamonde M, Sanz-de la Garza M, Sandoval E, Castella M, Martinez-Palli G. Multimodal prehabilitation as a strategy to reduce postoperative complications in cardiac surgery: A randomised controlled trial. Eur J Anaesthesiol. 2025 Nov 1;42(11):987-996. doi: 10.1097/EJA.0000000000002236. Epub 2025 Jul 16.
PubMed 40673713van der Hoofd Z, van Dijk-Huisman HC, Bongers BC, Scheenstra B, Maessen J, Lenssen AF. Preoperative Physical Fitness and Short-Term Postoperative Outcomes in Patients Undergoing Elective Cardiac Surgery: A Retrospective Cohort Study. Semin Cardiothorac Vasc Anesth. 2026 Sep;30(3):160-171. doi: 10.1177/10892532261427827. Epub 2026 Feb 21.
PubMed 41721796van der Hoofd, Z., et al., Predicting In-Hospital Complications and Delayed Recovery in Patients undergoing Cardiac Surgery via Sternotomy: Development and Internal Validation of Multivariable Predictions Models Submitted, 2025.
Steinmetz C, Bjarnason-Wehrens B, Baumgarten H, Walther T, Mengden T, Walther C. Prehabilitation in patients awaiting elective coronary artery bypass graft surgery - effects on functional capacity and quality of life: a randomized controlled trial. Clin Rehabil. 2020 Oct;34(10):1256-1267. doi: 10.1177/0269215520933950. Epub 2020 Jun 16.
PubMed 32546065