Remote Ischemic Preconditioning Does Not Improve the Six Minutes Walk Test Performance in Chronic Heart Failure...

Cycles of ischemia and reperfusion induced with a pressure cuff on a skeletal muscle, also know as remote ischemic preconditioning (RIPC), appears to improve performance in different time-trial events in healthy individuals. Our primary goal was to assess the effect of RIPC in heart failure (HF) patients' functional capacity using the six-minute walk test (6MWT). A randomized crossover design comparing RIPC (4 × five-minutes of upper arm ischemia) to the SHAM procedure was done in 15 patients prior to a 6MWT. The primary outcome measure was the total distance walked in a standardized 6MWT (20m corridor). Metabolic and hemodynamic responses were measured using gas exchange analysis with a portable metabolic analyzer and peripheral skeletal muscle oxygen saturation (smO₂) with near-infrared spectroscopy. The total distance travelled during 6MWT was not significantly different between the RIPC (347 ± 63 m) and the SHAM procedure (352 ± 65 m; p = 0.514). Relative oxygen uptake did not change when comparing interventions: 10.26 ± 2.01 ml/kg/min vs 10.69 ± 2.51 ml/kg/min (RIPC vs SHAM, respectively, p = 0.278). As well, no significant differences were observed for heart rate, respiratory exchange ratio, smO₂, and ventilation. Even though HF patients tolerated well the RIPC intervention, it did not provide any significant improvement in functional capacity and other physiological parameters in our sample of patients.