PB0808 - Hemostatic response to exercise training in patients with continuous-flow left ventricular assist device

Monday, July 11, 2022

6:30 PM – 7:30 PM

Location: Exhibition

Presentation Format: In-Person

Presenting Author(s)

Chris Hoi Houng H. Chan, Dr

Senior Research Fellow
Griffith University
Brisbane, Queensland, Australia

Co-Author(s)

MP

Margaret R Passmore

Lab Manager
Faculty of Medicine, University of Queensland
Brisbane, Queensland, Australia
OT

Oystein Tronstad

Physiotherapist
Physiotherapy Department, The Prince Charles Hospital
Brisbane, Queensland, Australia
HS

Helen Seale

Physiotherapist
Physiotherapy Department, The Prince Charles Hospital
Brisbane, Queensland, Australia
MB

Mahé Bouquet

Lab assistant
Faculty of Medicine, University of Queensland
Brisbane, Queensland, Australia
AH

Airlie Hogan

VAD coordinator
Department of Cardiology, The Prince Charles Hospital
Brisbane, Queensland, Australia
NS

Nicolas Sowden

Cardiologist
Department of Cardiology, The Prince Charles Hospital
Brisbane, Queensland, Australia
DP

David Platts

Cardiologist
Department of Cardiology, The Prince Charles Hospital
Brisbane, Queensland, Australia
WC

Wandy Chan

Cardiologist
Department of Cardiology, The Prince Charles Hospital
Brisbane, Queensland, Australia
AD

Alexander M Dashwood

Cardiologist
Department of Cardiology, The Prince Charles Hospital
Brisbane, Queensland, Australia
DM

David C McGiffin

Heart Surgeon
Cardiothoracic Surgery & Transplantation, The Alfred Hospital
Melbourne, Victoria, Australia
AM

Andrew J Maiorana

Exercise physiologist
Allied Health Department, Fiona Stanley Hospital
Perth, Western Australia, Australia
JS

Jacky Y Suen

Senior Research Fellow
University of Queensland
Brisbane, Queensland, Australia
JF

John F Fraser

Professor
Faculty of Medicine, University of Queensland
Brisbane, Queensland, Australia
BM

Bart Meyns

Full professor at KU Leuven
Department of Clinical Cardiac Surgery, KU Leuven
Leuven, Vlaams-Brabant, Belgium
LF

Libera Fresiello

Research Fellow
Department of Clinical Cardiac Surgery, KU Leuven
Leuven, Vlaams-Brabant, Belgium
SJ

Steven Jacobs

Assistant professor at KU Leuven
Department of Clinical Cardiac Surgery, KU Leuven
Leuven, Vlaams-Brabant, Belgium

Background: Acquired von Willebrand syndrome and platelet dysfunction are commonly diagnosed, which contributing to bleeding complications, in patients with a continuous-flow left ventricular assist device (CF-LVAD).

Aims: We aimed to investigate whether exercise training can stimulate endothelial release of von Willebrand factor (vWF) and organ-reserved platelets into blood circulation by increasing the squeezing stress surrounding peripheral blood vessel walls and internal organs, potentially mitigating the bleeding risk in CF-LVAD patients.

Methods: In a prospective, two-centred comparative cohort study, 21 patients with an implanted CF-LVAD (HeartMate 3, n=12 and HeartWare Ventricular Assist Device, n=9) either performed exercise at maximal intensity (n=13) on an ergometer for approximately 10 minutes or sub-maximal intensity (n=8) on a treadmill for 30 minutes. Blood samples were taken pre- and post-exercise for full blood examination, platelet aggregometry, vWF multimeric analysis, rotational thromboelastometry, coagulation, fibrinolytic and endothelial bio-marker analysis.

Results: Exercise training resulted in an increased average platelet count (235 to 263 ×103/µL, p=0.000009), with adenosine diphosphate (31 to 40 U, p=0.000012), thrombin receptor activating peptide-6 (55 to 65 U, p=0.000002), and ristocetin (25 to 32 U, p=0.0095) induced-platelet aggregation also enhanced. Endothelial activation was demonstrated by increased overall vWF multimers (21.3% to 25.3% in high-molecular-weight, p=0.00005; 20.4% to 25.1% in intermediate-molecular-weight, P=0.00013; 27.9% to 31.8% in low-molecular-weight, P=0.0021), collagen-binding vWF activity (1.0 to 1.2 U/mL, p=0.0008), ADAMTS13 (1.1 to 1.2 µg/mL, p=0.0113), tissue plasminogen activator (2.7 to 3.0 ng/mL, p=0.036) and D-dimers (3.1 to 3.4 µg/mL, p=0.0012). Additionally, exercise shortened clot formation times (66 to 63 seconds, p=0.0002), with a corresponding increase in maximum clot firmness (65.8 to 67.2 mm, p=0.00004).

Conclusion(s): Irrespective of device type and exercise regime, our results demonstrate that exercise training alters hemostatic parameters with increased endothelial release of vWF, platelet number and function, suggesting a potential non-pharmacological role in mitigating bleeding risk in patients with CF-LVAD.