Exercise Mildly Increases Transaortic Gradients in Aortic Stenosis With Preserved Ejection Fraction: An Invasive Hemodynamic Study
ABSTRACT
Background
The assessment of aortic stenosis (AS) severity remains a challenge in some patients, and hemodynamic exercise testing has been proposed as a diagnostic tool in this population. However, the current understanding of exercise hemodynamics in AS is limited.
Methods
Retrospective review of 34 adults (aged ≥ 18 years) with ≥ moderate AS and preserved left ventricular ejection fraction (LVEF) undergoing exercise invasive hemodynamics (supine cycle protocol) with simultaneous measurement of aortic and left ventricular pressures.
Results
Age was 77.1 (IQR 68.6; 84.1) years, and 50% were female. LVEF was 62.1 ± 6.6%. All patients were symptomatic. Resting aortic valve area (AVA) was 1.0 ± 0.2 cm2 and aortic valve (AV) systolic mean gradient 22.0 ± 7.3 mmHg. At peak exercise (40 [IQR 30; 60] W), AV systolic mean gradient (Δ3 [0.6; 7] mmHg, p < 0.001) and AVA (Δ0.2 [0; 0.6] cm2, p = 0.002) significantly increased, while stroke volume (SV) did not (Δ6.8 ± 19.4 ml; p = 0.07). Exercise-induced changes in AV systolic mean gradient were directly related to changes in cardiac output (r = 0.53, p = 0.003), being inversely related to exercise systemic vascular resistance (r = −0.60, p = 0.002). Elevated pulmonary artery wedge pressure was present in 41.2% at rest (≥ 15 mmHg) and 69.7% during exercise (≥ 25 mmHg).
Conclusions
Symptomatic patients with ≥ moderate AS and preserved LVEF experience small increases in AV mean gradient with exercise, and unlike the normal physiological response to exercise, there was no significant increase in SV. In most patients, AVA rose during exercise. Exercise-induced elevation in filling pressures was highly prevalent.
Conflicts of Interest
The authors declare no conflicts of interest.
Open Research
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
