Effect of High-Intensity Interval Training on Progression of Coronary Artery Vasculopathy in De Novo Heart Transplant Recipients

Purpose Coronary artery vasculopathy (CAV) leads to increased morbidity and mortality in heart transplant (HTx) recipients. We have previously shown that high-intensity interval training (HIT) in maintenance recipients significantly reduced CAV progression, as compared to a control group. Our hypothesis was that HIT compared to moderate intensity, continuous training (MICT) in de novo HTx recipients would show similar results. Methods 67 HTx recipients (mean ± SD age 49 ± 13, 72 (% men) were randomized to either nine months of HIT or MICT at mean 11 weeks (range 7 - 16) post HTx. The effect of training on CAV progression was assessed by matched intravascular ultrasound (IVUS) examinations at baseline and 12 months, and analyses were performed to measure change in Maximal Intimal Thickness (MIT), Percent Atheroma Volume (PAV) and Total Atheroma Volume (TAV). Results Age and sex were similar between the groups. Peak oxygen consumption (VO 2peak L/min ) improved with 12.5 ± 10.3 % in the HIT group vs. 8.7 ± 9.3 % in the MICT group (p=0.022). IVUS analysis revealed a relatively small increase in all the three main IVUS parameters in both groups: The mean ± SD increase in MIT was 0.08 ± 0.12mm in the HIT group vs. 0.06 ± 0.10 mm in the MICT group. The increase in PAV was 4.3 ± 5.6 % in the HIT group vs. 3.2 ± 3.9 % in the MICT group, and TAV increased with 20.0 ± 51.5 mm 3 in the HIT group vs. 25.7 ± 44.8mm 3 in the MICT group, but there were no significant differences between the groups (see Table 1). Furthermore, there were no significant correlations between VO 2peak and MIT, PAV or TAV in either of the groups. Conclusion The increase in VO2 peak was significantly greater in HIT patients as compared to the MICT group. However, there was no significant difference in progression of CAV between the two treatment groups. We await the results from the 3-year follow-up to evaluate potential long-term effects.