Supine ergometry induced changes of left ventricular function and pulmonary hypertension have an uneven prognostic relevance for asymptomatic aortic stenosis according to age and gender

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Risk stratification in the asymptomatic severe aortic stenosis (AS) remains a difficult task within the spectrum of its hemodynamic phenotypes, especially on aging demographics. Interplay of left ventricular function and AS hemodynamics may be studied using semisupine bicycle ergometry (SBE). Purpose Purpose of the study was to interrogate the prognostic relevance of SBE based evaluation of LV function and noninvasive hemodynamics in asymptomatic severe AS. Methods Seventy-eight asymptomatic severe AS patients (pts), followed up on valve clinic in a tertiary center (age 65±12 years, female 29), were referred for SBE. AS related cardiac events (independent decision for surgery, NYHA worsening) during a follow up of 33/21 months occurred in 25 pts (64% for age>65 vs 30% for age<65). Workload (Watts) and % achieved target heart rate (%targetHR) were considered surrogates for SBE efficiency. The following parameters (mean±SD) were estimated at rest(R) and SBE (Ex): Biplane LV ejection fraction (EF) and stroke volume (SV), 2D strain (SR), tricuspid peak gradient (TRPG), transmitral E/e, HR, systolic blood pressure (SBP), HR*SBP product and their respective % changes. Results Event group had a decreased SBE efficiency in workload (Watts: 59±16 vs 78±20, p<0.001), similar %target heart rate (73±13 vs 73±9), with differences among the continuous variables only in EFex (59±8 vs 63±7, p = 0.04) and %dLVEF (6±10 vs 12±10, p = 0.02). Categorical classification was performed for inadequate LV functional improvement at SBE, using the absolute cut off for <5% LVEF increase and the <3% for LVSR increase, as well as for an excessive increase in pulmonary hypertension at SBE, using the cut off for TRPG >55mmHg. Respective distribution of cases was similar for age category > or <=65 years (dEX <5: 46% vs 45%, dSR <3: 62% vs 87%, TRPGEx >55mmHg: 38% vs 48%, all p = ns). Kaplan Meier analysis for events using TRPG>55 was significant for females (log rank=3.2, p = 0.06/ figure1). Kaplan Meier analysis for events using dEF≥5 was significant for age <65 years (log rank =4.7, p = 0.03/figure2). LVSR cut off did not provide any difference in outcome. Conclusion SBE induced changes on LV function and pulmonary hypertension have an uneven risk stratification relevance according to age and gender. Dedicated algorithms to gender and age have to be applied for the improvement of prognostication in severe AS based on SBE.