97 Value of Cardiopulmonary Exercise and Non-invasive Haemodynamic assessment during Exercise in Patients with Asymptomatic Severe Aortic Stenosis

Background Timing of aortic valve replacement in patients with severe asymptomatic aortic stenosis (VD) is controversial. Exercise testing may uncover symptoms and early cardiac dysfunction. However there is little information on the value of cardiopulmonary exercise (CPX) testing combined with haemodynamic assessment during exercise in this patient group. We report preliminary results of CPX and haemodynamic data in this patient cohort. Methods 21 consecutive patients with severe VD underwent maximal CPX tests. Central haemodynamics including cardiac output were measured non-invasively at rest and during peak exercise. The results were compared to normal values from a cohort of healthy controls and depicted as % of predicted for normal healthy controls. Results The following preliminary observations were made and are depicted on the graphs: (1) All patients except one (5%) had peak oxygen consumption (VO 2max ) within the ranges for healthy controls. (2) Five patients (24%) had cardiac power output (CPO max ) below the range for healthy controls. (3) When plotted together relative to healthy controls the CPOmax of patients with severe VD were lagging below the VO2max, suggesting measurement of VO 2max alone may not pick out the ones with early cardiac dysfunction. Conclusion Haemodynamic assessment during exercise using direct indicators of cardiac function may be more sensitive than conventional cardiopulmonary exercise parameters in detecting early cardiac dysfunction in patients with severe asymptomatic aortic stenosis.