Abstract 12461: Cardiopulmonary Exercise Testing in 117 Moderate to Severe Aortic Stenosis Patients; A Prospective, Descriptive Study
Background: We hypothesized that cardiopulmonary exercise testing (CPET) compared to conventional exercise testing (CET) generates more conclusive results and differentiates patients with truly asymptomatic aortic stenosis (AS) from symptomatic AS and functional limitations due to other causes.
Methods: CET with additional CPET information were performed in 117 patients, median age 72 years (range 44-90), with asymptomatic or questionably symptomatic AS with AVA<1,3 cm2 or Vmax>3,5m/s.
Results of CPET were interpreted according to Wassermann algorithm and CET after the international guidelines. An abnormal CPET as peak oxygen uptake (pVO2) <80% of expected (i.e., true functional class II) or reproducible symptoms (dyspnea, angina, dizziness or syncope). False positive CET was defined as asymptomatic and non-reproducible blood pressure drop or non-reproducible dizziness. Trans thoracic echocardiography and BNP were performed and analysed for all patients. Supplemental tests were done (i.e., angiogram) if indicated.
Results: CPET was conclusive in 115 compared to 89 patients examined by CET (p<0.05). CET yielded a false positive result in 16 cases. We observed discrepancies between clinical functional classification and pVO2 in 37%. Non-AS-related abnormal CPET was due to ischemic heart disease, predominant lung disease or low effort. There were no differences between patients with normal CPET and those with abnormal CPET with regard to age, max velocity, AVA, E/E', BNP, or valvuloarterial impedance (Zva) (Table 1). During a mean follow-up of 233 days (±144) no deaths or instances of heart failure were observed.
Conclusions: In patients with moderate to severe AS, including older and sedentary persons, CPET is feasible, and compared to CET gives more conclusive results and helps differentiate between patients with truly asymptomatic AS and functional limitations due to AS or other causes.
- © 2011 by American Heart Association, Inc.