P5265Influence of exercise position for evaluating diastolic function in HFpEF: exercise echocardiography associated with cardiopulmonary test

Abstract

Background: The diagnosis of heart failure with preserved ejection fraction (HFpEF) is potentiated during exercise echocardiography. However, it is unknown if exercise position can influence the cardiac diastolic function response. Purpose: We aimed to evaluate the influence of exercising on semi‐supine and supine positions compared to upright position on cardiac diastolic function, myocardial wall stress and cardiopulmonary capacity in patients with HFpEF. Method: We evaluated simultaneously the cardiac function (cardiac ultrasound machine), the myocardial wall stress (NT‐proBNP) and the cardiopulmonary responses (Metalyzer system and Metasoft®Studio software) of 24 patients (11 male, 68±7 years) with HFpEF (average left ventricular EF = 58±8%). The patients performed exercise at upright, semi‐supine and supine positions in randomized order and were evaluated at rest, during steady‐state submaximal exercise and post‐peak exercise (ramp protocol). One way ANOVA for repeated measures was aplied, followed by paired t‐test comparisons. Between subjects correlations were performed. P<0.05 was considered for significance. Results: At rest, supine and semi‐supine positions caused higher values in E and e' velocities when compared to upright position (P<0.02) and E/e' was similar between the all three positions (P>0.06). During submaximal exercise, supine position provoked higher absolute value in E (P=0.005) and lower value in IVRT (P=0.005) when compared to upright position. Considering the relative response to exercise (%), supine position provoked lower increase in E and e' compared to upright (P<0.02) and semi‐supine (P<0.04) positions. However, E/e' increased in the same proportion for all three positions (P>0.40). At post‐peak exercise, both supine and semi‐supine positions caused higher absolute values in E, A, E/A ratio and e' (P<0.02), and lower value in IVRT (P<0.01) compared to upright position. Only supine position led to lower absolute value of E/e' (P<0.04) and lower relative increase in E and E/e' (%), compared to semi‐supine and upright positions (P<0.03). NT‐proBNP values were not influenced by exercise positions (P>0.15). VO2 and O2 pulse presented similar relative response to exercise in all three positions (P>0.28). Peak e' correlated positively with VO2 peak (r=0.416, P=0.04) and peak work load (r=0.417, P=0.04). Rest E/e' and peak E/e' correlated negatively with VO2 peak (r= ‐0.400, P=0.05 and r= ‐0.445, P=0.03; respectively). Conclusions: Because of the influence of supine position on usual echocardiographic parameters for evaluating diastolic function during exercise and postpeak exercise, we recommend semi‐supine or upright position for assessing diastolic function up to maximal effort and to confirm the diagnosis of HFpEF. Exercise echocardiography can be certainly associated with cardiopulmonary exercise testing to aid on the diagnosis of HFpEF.