# Haemostasis and fibrinolysis after regular high-intensity interval training in patients with coronary artery disease: a randomised controlled trial

PMID: 36428083
Journal: Open heart
Published: 2022-11-01
Authors: Kristiansen J, Grove EL, Sjúrðarson T, Rasmussen J, Mohr M, Kristensen SD, Hvas AM

## Question

Whether regular supervised high-intensity exercise training reduces platelet aggregation and coagulation and increases fibrinolysis in patients with stable coronary artery disease compared with standard medical care.

## Summary

This randomized controlled trial tested whether 12 weeks of supervised low-volume high-intensity whole-body endurance exercise changed haemostasis or fibrinolysis markers in stable coronary artery disease. One hundred sixty-nine patients were randomized and 142 completed the study. The exercise arm trained three times weekly on rowing ergometers, but platelet aggregation, thrombin generation, and clot lysis did not differ significantly from standard care after 12 weeks, despite prior reporting from the same trial that VO2peak improved by about 10% in the exercise group.

## Population

- Stable adults with angiographically confirmed coronary artery disease, mostly older men, randomized to supervised high-intensity rowing exercise or standard medical care.
- Sample size: 142
- Age: 67 +/- 9 years among completers.
- Sex: 83% male, 17% female among completers.
- Fitness level: Able to perform strenuous exercise; baseline VO2peak values were not reported in this article.
- Health status: Stable coronary artery disease; high use of antiplatelet therapy, statins, and cardiovascular medications.

## Methodology

- Randomized controlled trial with 1:1 allocation to supervised high-intensity exercise training plus standard care or standard care alone.
- 12 weeks, with blood sampling at baseline, 6 weeks, and 12 weeks.
- Department of Medicine, National Hospital of the Faroe Islands, Torshavn; supervised exercise on rowing ergometers.
- Randomized and controlled study design.

## Protocol

- Supervised low-volume high-intensity rowing exercise.
- Modality: Rowing ergometer.
- Sets or repetitions: Similar intervals throughout most of the training period; exact number of intervals was not specified in this article.
- Intensity: High-intensity exercise training; exact target not specified in this article.
- Session duration: 18 active minutes; total session duration not specified.
- Frequency: 3 sessions per week.
- Program length: 12 weeks.
- Progression: First 2 weeks lower intensity for familiarisation and rowing technique; similar intervals thereafter.
- Standard care.
- Modality: Usual daily routine and standard medical care.
- Program length: 12 weeks.
- Progression: Participants were encouraged not to alter exercise or lifestyle habits.

## Outcomes

### ADP-induced platelet aggregation
Status: no clear change
No significant between-group difference from baseline to 12 weeks.

Exercise delta -15 AU x min, 95% CI -70 to 40; standard care delta -26 AU x min, 95% CI -77 to 26; p=0.44.

### Endogenous thrombin potential
Status: no clear change
No significant between-group difference from baseline to 12 weeks, although a transient 6-week reduction in exercise was discussed.

Exercise median delta -5%, 95% CI -12 to 3; standard care median delta -6%, 95% CI -13 to 1; p=0.26.

### 50% clot lysis time
Status: no clear change
No significant between-group difference from baseline to 12 weeks.

Exercise median delta -9%, 95% CI -23 to 7; standard care median delta -17%, 95% CI -29 to -3; p=0.60.

### VO2peak
Status: improved
The exercise training programme was reported to improve VO2peak by about 10% in the exercise group only.

Exact values not provided in this article; the result is cited to a related protocol report.

## Practical Insights

- In stable CAD, HIIT may improve cardiorespiratory fitness without necessarily improving haemostasis or fibrinolysis biomarkers.
- Clinical HIIT evidence should preserve screening, supervision, medication context, and exclusion boundaries.
- A familiarisation phase can be important when using demanding whole-body ergometer modalities in older clinical populations.

## Limitations

- The exact interval structure and intensity target are not provided in this article.
- Aspirin and other common cardiovascular medications may mask platelet or haemostatic effects.
- Exercise-group completion was lower than standard care completion.
- Stable CAD results may not apply to patients shortly after acute coronary syndrome or revascularisation.

## Safety And Adherence

- No adverse events or injuries were reported in the extracted article text.
- The trial excluded several higher-risk cardiac and pulmonary conditions and anticoagulant treatment.
- All patients gave written informed consent and the Faroese ethical committee approved the study.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/36428083/) (pubmed)
- [DOI](https://doi.org/10.1136/openhrt-2022-002127) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9703332/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.