Prediction of symptom development and aortic valve replacement in patients with low-gradient severe aortic stenosis.

AIMS: Current evidence on the prognostic value of exercise stress echocardiography (ESE) in asymptomatic patients with low-gradient severe aortic stenosis (AS) is limited. Therefore, this study aimed to elucidate its prognostic implications for patients with low-gradient severe AS and determine the added value of ESE in risk stratification for this population.

METHODS AND RESULTS: This retrospective observational study included 122 consecutive asymptomatic patients with either moderate [mean pressure gradient (MPG) < 40 mmHg and aortic valve area (AVA) 1.0-1.5 cm2 ] or low-gradient severe (MPG < 40 mmHg and AVA < 1.0 cm2 ) AS and preserved left ventricular ejection fraction (≥50%) who underwent ESE. All patients were followed up for AS-related events. Of 143 patients, 21 who met any exclusion criteria, including early interventions, were excluded, and 122 conservatively managed patients [76.5 (71.0-80.3) years; 48.3% male] were included in this study. During a median follow-up period of 989 (578-1571) days, 64 patients experienced AS-related events. Patients with low-gradient severe AS had significantly lower event-free survival rates than those with moderate AS (log-rank test, P < 0.001). Multivariable Cox regression analysis showed that the mitral E / e ' ratio during exercise was independently associated with AS-related events (hazard ratio = 1.075, P < 0.001) in patients with low-gradient severe AS.

CONCLUSION: This study suggests that asymptomatic patients with low-gradient severe AS have worse prognoses than those with moderate AS. Additionally, the mitral E / e ' ratio during exercise is a useful parameter for risk stratification in patients with low-gradient severe AS.