Effects of High-Intensity Interval Training on Cardiopulmonary Function in Patients with Acute Myocardial Infarction...

This study aims to explore the efficacy and safety of high-intensity interval training (HIIT) in patients with acute myocardial infarction (AMI) with or without cardiac arrest (CA).

A retrospective analysis of 100 patients with AMI who underwent primary percutaneous coronary intervention was conducted. Fifty patients experienced CA, whereas the other fifty did not. A HIIT program was performed three times per week for a 12-week duration. The target heart rate (THR) method was used to guide the intensity of exercise. The cardiopulmonary function indices include maximum oxygen uptake (VO₂ max), anaerobic threshold (AT), ventilatory efficiency (E/CO₂ slope), oxygen uptake efficiency slope (OUES), metabolic equivalents (METs), oxygen pulse (VO₂/HR), and heart rate recovery at 1 minute (HRR₁).

After HIIT, VO₂max in the CA group increased from 21.96±4.40 to 23.85±3.28 mL/kg/min (95% CI: 1.31 to 2.47; P <0.001). AT increased from 15.01±3.09 to 15.97±2.09 mL/kg/min (95% CI: 0.41 to 1.51; P =0.001), while the VE/VCO₂ slope decreased from 29.26±3.14 to 27.56±4.42 L/l (95% CI: -3.01 to -0.39; P =0.047). OUES increased from 1762.49±653.77 to 1960.08±527.43 (95% CI: 55.00 to 340.18; P =0.0078). METs increased from 6.27±1.25 to 6.81±0.93 (95% CI: 0.37 to 0.71; P <0.001). Additionally, oxygen pulse (O₂/HR) increased from 12.32±2.08 to 13.74±0.90 mL (95% CI: 0.87 to 1.97; P <0.001), and HRR₁ improved from 16.65±7.75 to 20.1±6.64 (95% CI: 0.87 to 6.03; P =0.010); similar improvements were also observed in the non-CA group. The adverse events during rehabilitation were comparable between the two groups.

Overall, HIIT-based rehabilitation was associated with significant improvements in cardiopulmonary function, with comparable outcomes in AMI patients with and without CA.