Effects of high‐intensity interval training in patients with coronary artery disease after percutaneous coronary intervention: A systematic review and meta‐analysis

AIM: To evaluate whether high‐intensity interval training (HIIT) was superior to low‐intensity training or usual care among patients after percutaneous coronary intervention. The hypothesis was that HIIT would help patients after percutaneous coronary intervention (PCI) improve cardiopulmonary function, lipid profiles and in‐stent restenosis. DESIGN: A systematic review and meta‐analysis were conducted according to the Preferred Reporting Items for Systematic Review and Meta‐analysis (PRISMA)2009 Checklist. METHODS: Randomized controlled trials (RCTs) focusing on HIIT programme in patients after PCI were searched in Cochrane Library, Web of Science Core Collection, EMbase, PubMed, China National Knowledge Infrastructure (CNKI) and SinoMed from the inception to 24 March 2020. Standard Mean difference (SMD) and 95% confidence intervals (CI) were performed to summarize the effect sizes. RESULTS: Six RCTs (247 patients) met the criteria. HIIT programme had a statistically significant effect on raising left ventricular ejection function (LVEF) (SMD = 0.38, 95%CI [0.03, 0.73], I (2) = 3%), VO(2peak) (SMD = 0.94, 95%CI [0.61, 1.28], I (2) = 0%), as well as improving the serum level of high‐density lipoprotein (SMD = 0.55, 95%CI [0.06, 1.03], I (2) = 0%) and late luminal loss (SMD = −0.65, 95%CI [−1.07, −0.23], I (2) = 0%). But HIIT had no prominent effect on improving heart rate (SMD = −0.04, 95%CI [−0.29, 0.21], I (2) = 0%). Summarily, HIIT programme appears to be favourable for CAD patients after PCI by improving cardiopulmonary function, such as LVEF and VO(2peak), as well as reducing late luminal loss in per stented arteries. Nevertheless, HIIT has no advantage for adjusting heart rate. More researches with rigorous methods are warranted to explore the controversy about lipid profiles.