Kari Nytrøen
- Postdoctoral research fellow, PhD, M.Sc
Kari Nytrøen successfully defended her thesis "Chronotropic responses and effect of high intensity interval based aerobic exercise in heart transplant recipients." in February 2014.
Physiotherapist and doctoral candidate Kari Nytrøen found that high-intensity interval training is a safe and effective form of exercise that improves stamina, enduring muscle strength and overall health in stable heart transplant patients.
Interval training is known for its positive effects. Nytrøen and co-workers wanted to investigate whether interval training has the same good effect among heart transplant patients as it has in the rest of the population. This type of exercise has been considered "unphysiologic" for heart transplant patients as they lack nerve supply to the new heart, leading to reduced heart rate response.
In this thesis it was shown that the heart rate response is partially normalized in most patients one year after transplantation and that the interval training performed by patients on average 4 years after transplantation led to:
- Increased oxygen uptake / better fitness (13% increase)
- Increased endurance of muscle strength (17% increase)
- Better quality of life
- Decreased progression (> 50%) of vasculopathy (a special form of arteriosclerosis affecting cardiac transplant patients = cardiac allograft vasculopathy)
In conclusion, interval training is a safe and effective form of exercise that is recommended to improve the fitness and health of all heart transplant recipients well in way in the recovery process, given that their condition has remained stable and that they are othervise healthy. In addition to improved fitness and enduring muscle strength, interval training slows the development of vasculopathy, which may lead to reduced morbidity and mortality in this patient population.
Publications 2024
A Review of High-Intensity Interval Training in Heart Transplant Recipients: Current Knowledge and Future Perspectives
J Cardiopulm Rehabil Prev, 44 (3), 150-156
DOI 10.1097/HCR.0000000000000847, PubMed 38488139
Prevention and Rehabilitation After Heart Transplantation: A Clinical Consensus Statement of the European Association of Preventive Cardiology, Heart Failure Association of the ESC, and the European Cardio Thoracic Transplant Association, a Section of ESOT
Transpl Int, 37, 13191
DOI 10.3389/ti.2024.13191, PubMed 39015154
Prevention and rehabilitation after heart transplantation: A clinical consensus statement of the European Association of Preventive Cardiology, Heart Failure Association of the ESC, and the European Cardio Thoracic Transplant Association, a section of ESOT
Eur J Prev Cardiol, 31 (11), 1385-1399
DOI 10.1093/eurjpc/zwae179, PubMed 38894688
Prevention and rehabilitation after heart transplantation: A clinical consensus statement of the European Association of Preventive Cardiology, Heart Failure Association of the ESC, and the European Cardio Thoracic Transplant Association, a section of ESOT
Eur J Heart Fail, 26 (9), 1876-1892
DOI 10.1002/ejhf.3185, PubMed 38894693
Publications 2023
Prognostic value of intravascular ultrasound early after heart transplantation
Eur Heart J, 44 (48), 5160-5162
DOI 10.1093/eurheartj/ehad648, PubMed 37850514
Kinetics of Torque Teno virus in heart transplant patients
Hum Immunol, 84 (12), 110720
DOI 10.1016/j.humimm.2023.110720, PubMed 37867096
Factors Associated With Sinoatrial Reinnervation After Heart Transplantation
Transplant Direct, 9 (12), e1553
DOI 10.1097/TXD.0000000000001553, PubMed 37928482
Effects of high-intensity interval training on cardiac remodelling, function and coronary microcirculation in de novo heart transplant patients: a substudy of the HITTS randomised controlled trial
BMJ Open Sport Exerc Med, 9 (3), e001331
DOI 10.1136/bmjsem-2022-001331, PubMed 37440977
Publications 2022
[The Norwegian Health Archives Registry opens new doors for research]
Tidsskr Nor Laegeforen, 142 (16)
DOI 10.4045/tidsskr.22.0570, PubMed 36345643
Ready for SDM- evaluation of an interprofessional training module in shared decision making - A cluster randomized trial
Patient Educ Couns, 105 (7), 2307-2314
DOI 10.1016/j.pec.2022.03.013, PubMed 35365369
Predictors of Hypertension Development 1 Year After Heart Transplantation
Transplantation, 106 (8), 1656-1665
DOI 10.1097/TP.0000000000004068, PubMed 35238853
Publications 2021
Early Signs of Sinoatrial Reinnervation in the Transplanted Heart
Transplantation, 105 (9), 2086-2096
DOI 10.1097/TP.0000000000003580, PubMed 33323767
Strong evidence for parasympathetic sinoatrial reinnervation after heart transplantation
J Heart Lung Transplant, 41 (7), 898-909
DOI 10.1016/j.healun.2021.11.005, PubMed 34924265
Ready for SDM: evaluating a train-the-trainer program to facilitate implementation of SDM training in Norway
BMC Med Inform Decis Mak, 21 (1), 140
DOI 10.1186/s12911-021-01494-x, PubMed 33931046
A randomized clinical study using optical coherence tomography to evaluate the short-term effects of high-intensity interval training on cardiac allograft vasculopathy: a HITTS substudy
Clin Transplant, 36 (1), e14488
DOI 10.1111/ctr.14488, PubMed 34747048
Functional evidence of low-pressure cardiopulmonary baroreceptor reinnervation 1 year after heart transplantation
Eur J Appl Physiol, 121 (3), 915-927
DOI 10.1007/s00421-020-04586-0, PubMed 33389144
Publications 2020
Ready for shared decision making: Pretesting a training module for health professionals on sharing decisions with their patients
J Eval Clin Pract, 26 (2), 610-621
DOI 10.1111/jep.13380, PubMed 32114700
Effect of high-intensity interval training in young heart transplant recipients: results from two randomized controlled trials
BMC Sports Sci Med Rehabil, 12, 35
DOI 10.1186/s13102-020-00180-1, PubMed 32518655
Long-term effects of high-intensity training vs moderate intensity training in heart transplant recipients: A 3-year follow-up study of the randomized-controlled HITTS study
Am J Transplant, 20 (12), 3538-3549
DOI 10.1111/ajt.16087, PubMed 32484261
High-intensity interval training and health-related quality of life in de novo heart transplant recipients - results from a randomized controlled trial
Health Qual Life Outcomes, 18 (1), 283
DOI 10.1186/s12955-020-01536-4, PubMed 32807179
Publications 2019
Autonomic cardiovascular control changes in recent heart transplant recipients lead to physiological limitations in response to orthostatic challenge and isometric exercise
Eur J Appl Physiol, 119 (10), 2225-2236
DOI 10.1007/s00421-019-04207-5, PubMed 31407088
Effect of High-Intensity Interval Training in De Novo Heart Transplant Recipients in Scandinavia
Circulation, 139 (19), 2198-2211
DOI 10.1161/CIRCULATIONAHA.118.036747, PubMed 30773030
Response by Nytrøen et al to Letter Regarding Article, "Effect of High-Intensity Interval Training in De Novo Heart Transplant Recipients in Scandinavia"
Circulation, 140 (17), e735-e736
DOI 10.1161/CIRCULATIONAHA.119.042458, PubMed 31634012
Publications 2018
Rapid methods including network meta-analysis to produce evidence in clinical decision support: a decision analysis
Syst Rev, 7 (1), 168
DOI 10.1186/s13643-018-0829-z, PubMed 30342549
Clinical features and determinants of VO2peak in de novo heart transplant recipients
World J Transplant, 8 (5), 188-197
DOI 10.5500/wjt.v8.i5.188, PubMed 30211027
Importance of physical capacity and the effects of exercise in heart transplant recipients
World J Transplant, 8 (1), 1-12
DOI 10.5500/wjt.v8.i1.1, PubMed 29507857
Publications 2017
The development and feasibility of a personal health-optimization system for people with bipolar disorder
BMC Med Inform Decis Mak, 17 (1), 102
DOI 10.1186/s12911-017-0481-x, PubMed 28693482
Immediate response in markers of inflammation and angiogenesis during exercise: a randomised cross-over study in heart transplant recipients
Open Heart, 4 (2), e000635
DOI 10.1136/openhrt-2017-000635, PubMed 29225901
Publications 2016
Patient-Important Outcomes in the Long-Term Treatment of Bipolar Disorder: A Mixed-Methods Approach Investigating Relative Preferences and a Proposed Taxonomy
Patient, 9 (2), 91-102
DOI 10.1007/s40271-015-0128-x, PubMed 25990222
Long-term effects of high-intensity interval training in heart transplant recipients: A 5-year follow-up study of a randomized controlled trial
Clin Transplant, 31 (1)
DOI 10.1111/ctr.12868, PubMed 27865004
Publications 2015
What matters to patients? A systematic review of preferences for medication-associated outcomes in mental disorders
BMJ Open, 5 (4), e007848
DOI 10.1136/bmjopen-2015-007848, PubMed 25854979
Design and rationale of the HITTS randomized controlled trial: Effect of High-intensity Interval Training in de novo Heart Transplant Recipients in Scandinavia
Am Heart J, 172, 96-105
DOI 10.1016/j.ahj.2015.10.011, PubMed 26856221
Peak oxygen uptake and self-reported physical health are strong predictors of long-term survival after heart transplantation
Clin Transplant, 30 (2), 161-9
DOI 10.1111/ctr.12672, PubMed 26589579
Publications 2013
Effect of exercise in heart transplant recipients
Am J Transplant, 13 (2), 527
DOI 10.1111/ajt.12046, PubMed 23356900
[Exercise after heart transplantation--old principles needs reevaluation]
Tidsskr Nor Laegeforen, 133 (19), 2030-1
DOI 10.4045/tidsskr.13.0903, PubMed 24129530
Exercise after heart transplantation: An overview
World J Transplant, 3 (4), 78-90
DOI 10.5500/wjt.v3.i4.78, PubMed 24392312
Effect of high-intensity interval training on progression of cardiac allograft vasculopathy
J Heart Lung Transplant, 32 (11), 1073-80
DOI 10.1016/j.healun.2013.06.023, PubMed 23906899
Heart transplant systolic and diastolic function is impaired by prolonged pretransplant graft ischaemic time and high donor age: an echocardiographic study
Eur J Cardiothorac Surg, 44 (2), e97-104
DOI 10.1093/ejcts/ezt233, PubMed 23657552
Publications 2012
High-intensity interval training improves peak oxygen uptake and muscular exercise capacity in heart transplant recipients
Am J Transplant, 12 (11), 3134-42
DOI 10.1111/j.1600-6143.2012.04221.x, PubMed 22900793
Muscular exercise capacity and body fat predict VO(2peak) in heart transplant recipients
Eur J Prev Cardiol, 21 (1), 21-9
DOI 10.1177/2047487312450540, PubMed 22659939
One year of high-intensity interval training improves exercise capacity, but not left ventricular function in stable heart transplant recipients: a randomised controlled trial
Eur J Prev Cardiol, 21 (2), 181-91
DOI 10.1177/2047487312469477, PubMed 23185084
Publications 2011
Chronotropic responses to exercise in heart transplant recipients: 1-yr follow-up
Am J Phys Med Rehabil, 90 (7), 579-88
DOI 10.1097/PHM.0b013e31821f711d, PubMed 21765276