Value of exercise echocardiography in paradoxical low gradient severe aortic stenosis

European Heart Journal

3 October 2022

Organised by:

Abstract

Low-flow and/or low-gradient paradoxical severe aortic stenosis (AS) is a controversial entity from a diagnostic and prognostic point of view. We aimed to assess the role of exercise echocardiography (ExE) in asymptomatic or equivocal symptoms patients with this condition.

Methods

Fifty patients (mean age 74±11 years, 70% women) with severe AS (aortic valve area [AVA] <1 cm²) and low-flow low-gradient (stroke volumen <35 ml/m²; mean gradient <40 mmHg), or only low gradient (n=27) AS, and preserved LV ejection fraction (LVEF >50%) were studied by treadmill ExE. AVA, gradients, LVEF and wall motion score index (WMSI) were assessed.

Results

Maximal achieved workload was 6.7±2.2 metabolic equivalents (METs), and LVEF (%) increased with exercise from 59±8 to 63±10. Symptoms were elicited in 14 patients (8 angina; 6 dyspnea). Five patients had wall motion abnormalities (WMAs) at rest (10%) and 18 at exercise (36%). Angiography showed CAD in 19 patients (exercise WMAs in 10) and was normal in 17 (exercise WMAs in 3). Maximum/mean transaortic gradients increased from 51±12/28±7 mmHg to 68±19/35±8 mmHg with exercise. Fourteen patients had mean gradient ≥40 mmHg with exercise (28%). There was a trend towards smaller AVA at rest and exercise in patients with exercise mean gradient ≥40 mmHg (0.78 vs 0.87 cm², p=0.06; and 0.83 vs 0.97 cm², p=0.07). During follow-up of 20±17 months, there were 35 events: 2 deaths, 3 admittances for cardiac failure, 2 myocardial infarctions, 26 prosthesis implantations due to worsening (with coronary intervention in 8), and 2 revascularizations. Independent predictors of events were treatment with digoxine (HR=31.3, 95% CI: 5.2–187.5, p<0.001) and exercise WMSI (HR=12.3, 95% CI: 3.6–41.8, p<0.001).

Conclusions

ExE offers supplementary information in low gradient severe AS. In 1/3 symptoms developed. Also in 1/3 there was significant increase in gradients. The presence of exercise WMAs was able to predict outcome.

Funding Acknowledgement

Type of funding sources: None.