Thyroid hormone signalling is altered in response to physical training in patients with end-stage heart failure and mechanical assist devices: potential physiological consequences?
Adamopoulos S, Gouziouta A, Mantzouratou P, et al.Interact Cardiovasc Thorac Surg. 2013;17(4):664-8.
Aims
To investigate the physiological consequences of thyroid hormone signalling if altered by physical training in participants with end-stage heart failure and mechanical assist devices.
Interventions
Patients undergo training which includes respiratory physiotherapy, early mobilization, progressive aerobic and resistance exercise. In addition they performed exercise training using a bicycle or treadmill at home for 45 minutes four times per week. The control group were advised to walk every day for 30-40 minutes and did not receive exercise training.
Participants
26 patients implanted with either intracorporeal left ventricular assist device or with extracorporeal or biventricular assist device.
Outcomes
The outcomes included measurements of thyroid receptor protein and total and phosphorylated protein kinase b and c-jun n-terminal kinase and thyroid hormone levels.
Follow-up
Not reported.
CET Conclusions
This paper presents the results of a secondary study conducted alongside a trial of physical training regimens following the insertion of a Ventricular Assist Device (VAD) for heart failure. After insertion of VAD the patients in the training group had a significant increase in plasma T3 levels, while T4 and TSH levels were unchanged. Expression of thyroid hormone receptor protein TRα1 within myocardial cell nuclei was increased following training compared to the control group. Levels of activated AKT were increased, while JNK was decreased representing activation of growth signalling pathways following training in hearts with implanted VAD. All patients still progressed to transplantation.
Data analysis
Per protocol analysis
Trial registration
Not reported.