NIVA derived from ECG signals yielded equivalent threshold estimates for heart rate (mean difference -0.46 bpm) and exercise load compared to the reference-standard VT2 in healthy adults.
Cross-Sectional (n=74)
Yes
Does ECG-derived ventilatory phase analysis (NIVA) accurately determine the second ventilatory threshold compared to standard cardiopulmonary exercise testing in healthy adults?
ECG-derived ventilatory phase analysis (NIVA) provides an accurate, non-invasive estimation of the second ventilatory threshold comparable to standard cardiopulmonary exercise testing.
Effect estimate: Mean difference -0.46 bpm (95% CI -2.10; 1.17)
p-value: p=<0.001
Abstract A ubiquitously available and accurate non-invasive ventilatory threshold assessment (NIVA) would substantially improve real-world performance assessment evaluation in both clinical and elite sports settings. We hypothesised that ECG-derived ventilatory phase analysis achieves reference-standard accuracy for second ventilatory threshold (VT2) determination. 74 healthy adults performed stepwise cardiopulmonary exercise testing with simultaneous lactate sampling to retrieve VT2 and lactate-based (Dmax; LT2) thresholds. Threshold agreement was evaluated for heart rate (HR) and exercise load (W) between VT2, LT2, age-estimated HR (HR-Est) and NIVA. In 66 assessable datasets, NIVA and VT2 yielded equivalent threshold estimates for HR (− 0.46 bpm; 90% CI − 2.10;1.17) and exercise load (0.46 W; 90% CI − 2.35; 3.27). VT2 and HR-Est diverged (HR − 7.22 bpm, p < 0.001; load − 6.26 W; p < 0.001). LT2 was available in 58 subjects and differed from both VT2 ( p < 0.001) and NIVA ( p < 0.001). Correlations supported these findings, with close associations between VT2 and NIVA (HR r = 0.84; load r = 0.96). NIVA derived a high-intensity performance threshold from ECG signals with reference-standard fidelity and showed close agreement with CPET-derived VT2. Its performance and accessibility make it attractive for frequent reassessment of a VT2-aligned threshold without the need for spiroergometry or lactate measurements. Validation across devices, protocols, populations, and real-world signal conditions is warranted.
Heinz et al. (Tue,) conducted a cross-sectional in Healthy adults (n=74). Non-invasive ventilatory threshold assessment (NIVA) vs. Cardiopulmonary exercise testing (CPET) derived second ventilatory threshold (VT2) was evaluated on Heart rate at second ventilatory threshold (Mean difference -0.46 bpm, 95% CI -2.10; 1.17, p=<0.001). NIVA derived from ECG signals yielded equivalent threshold estimates for heart rate (mean difference -0.46 bpm) and exercise load compared to the reference-standard VT2 in healthy adults.