Predictors of exercise capacity and symptoms in severe aortic stenosis

AIMS: This study investigated the association between invasive and non-invasive estimates of left ventricular (LV) filling pressure and exercise capacity, in order to find new potential candidates for risk markers in severe aortic valve stenosis (AS). METHODS AND RESULTS: Twenty-nine patients with AS, aortic valve area (AVA) < 1 cm(2), performed a symptom-limited multistage supine bicycle exercise test. Immediately before the exercise test, the pulmonary capillary wedge pressure (PCWP), Doppler index for LV filling (E/e'), and left atrial (LA) volume were measured. Symptomatic status was determined by senior staff doctors blinded to the results of this study. All patients terminated the exercise test because of dyspnoea. There were no significant differences in AVA between asymptomatic patients (n = 9) and symptomatic patients (n = 20), and AVA did not correlate with exercise capacity (r = -0.16, P = NS). In contrast, PCWP, LA volume, and E/e' were significantly increased in the symptomatic group and they all correlated with exercise capacity (r = -0.66, -0.75, and -0.62, respectively, P < 0.001). Receiver operating characteristic curve analysis confirmed that PCWP, LA volume index, and E/e' all provided incremental information [area under the curve (AUC) = 0.90, 0.92, and 0.90, respectively, P < 0.05] over AVA index (AUC = 0.66, NS) in predicting symptomatic status. CONCLUSION: PCWP, LA volume, or E/e' is closely related to exercise capacity and symptomatic status, and may therefore be important markers of disease severity in AS. Clinical Trials.gov Identifier: NCT00252317 (http://clinicaltrials.gov/ct2/results?term=NCT00252317).