Left ventricular diastolic function reaches its peak at the anaerobic threshold in heart failure
Y Desaki, J Morimoto, M Taniguchi, N Higashimoto, A TanakaAbstract
Background
While left ventricular (LV) diastolic function at rest is a well-established predictor of future cardiac events in heart failure (HF), its dynamic response during exercise remains unclear. Previous observations suggest that LV diastolic dimensions peak at the anaerobic threshold (AT) in HF patients. We hypothesized that diastolic function, as assessed by mean e', also reaches its maximum at the AT during a ramp exercise stress test. This study aimed to identify the maximal point of LV diastolic function using simultaneous cardiopulmonary exercise testing and stress echocardiography (CPET-SE).
Purpose
This study aimed to identify the maximal point of LV diastolic function using CPET-SE.
Methods
We enrolled 23 HF patients receiving guideline-directed medical therapy who underwent CPET-SE with a ramp exercise protocol. Echocardiographic parameters, including mean e' and cardiac output (CO), were measured at rest, 2 minutes after warm-up (WU), at the AT, and at peak exercise. These values were compared across each phase.
Results
Mean e' significantly increased and peaked at AT (rest: 5.5±1.3 cm/s; WU: 6.4±1.4 cm/s; AT: 8.5±2.5 cm/s; peak: 7.9±2.2 cm/s; p<0.05), whereas CO continued to rise and peaked at peak exercise (rest: 4.0±1.1 L/min; WU: 5.4±1.7 L/min; AT: 6.8±1.8 L/min; peak: 7.8±2.6 L/min; p<0.05).
Conclusions
In HF patients, LV diastolic function, as represented by mean e', peaks at the anaerobic threshold, while CO continues to rise until peak exercise. Given that resting diastolic function predicts adverse outcomes, the peak diastolic function during exercise, particularly at the AT, may have clinical significance in prognostic assessment.Result e'