Interval training improves vascular function in patients with repaired tetralogy of Fallot
In adults with repaired tetralogy of Fallot (ToF), high-intensity interval training is effective in improving quality of life (QoL), vascular function, exercise capacity, fibrinogen levels and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, according to a recent study.
The researchers randomized 27 adults (mean age 38.5±8.7 years; 63 percent female) with repaired ToF to receive either high-intensity interval training (n=9), moderate-intensity continuous training (n=9) or usual care (n=9).
With a mean adherence of 91.1 percent, both exercise interventions were safe and no deaths or adverse events were recorded. There were likewise no side effects, such as dizziness or palpitations, and significant changes in cardiac size and function.
Both exercise interventions resulted in significant improvements from baseline in workload capacity (p<0.05 for both), but only interval training was significantly associated with improvements in peak oxygen uptake (21.2–22.9 mL/kg/min; p<0.05).
Similarly, only interval training led to significant improvements from baseline in vascular function parameters such as pulse wave velocity (5.4–4.7 m/s; p<0.05) and flow-mediated dilation (8.4–12.9 percent; p<0.05). Improvements were also significantly better when compared with controls (p<0.05 for both).
In terms of serum biomarkers, interval training resulted in significantly higher high-density lipoprotein cholesterol levels (1.26–1.33 mmol/L; p<0.05) but significantly reduced fibrinogen (2.67–2.46 g/L; p<0.05) and NT-proBNP (202–190 ng/L; p<0.05) levels. The continuous training regimen did not result in these changes.
In contrast, a significant improvement in scores in the mental component of the 36-item Short Form Survey was associated with the continuous exercise regimen (87–93 points; p<0.05).
“Our findings suggest differential appreciation of both exercise types–namely, that high-intensity interval training improves [peak oxygen uptake], vascular function and disease specific biomarkers, whereas continuous training improves cardiac autonomic function and mental domain of QoL,” said researchers.