Test de esfuerzo con consumo de oxígeno en insuficiencia cardíaca avanzada: influencia de la comorbilidad en su valor pronóstico

Abstract

INTRODUCTION: Exercise intolerance is one of the main symptoms of heart failure (HF) and maximal oxygen uptake (V02 max) is a key para meter to assess it. OBJECTIVES: Our primary objective was to identify which clinical parameters are the most important determinants of V02 max in a cohort of HF. As a secondary objective, we aimed to evaluate the impact of the main comorbidities associated with HF on V02 max. METHODS We conducted a retrospective observational study that included patients with HF seen in the specialized Cardiology unit of the Complejo Hospitalario Universitario de A Coruña (CHUAC) who underwent CPET between 2009 and 2019 as part of the standard clinical protocol. Follow-up will extend until December 2020. Collect baseline clinical characteristics as well as specific variables in relation to the CPET. RESULTS: Six variables remained as independent predictors of V02 máx: older age, worse NYHA functional class, higher plasma NT-proBNP value and higher body mass index (BMI) were statistically significantly and independently associated with lower V02 max. In addition, higher TAPSE and a higher plasma hemoglobin value were associated with higher V02 max value. In the univariate survival analysis, we observed an increased risk of death or cardiac transplantation according to lower V02 max values; however, this association lost its statistical significance after multivariate adjustment far the 6 clinical determinants of V02 max and, therefore, was not shown to be independent. The overall discriminative ability of VO2 max to classify the risk of death ar cardiac transplantation at 1-year follow-up was low (a rea under the ROC curve= 0.63). The cutoff points VO2 max <14 ml/kg/min and VO2 max <12 ml/kg/min presented a sensitivity of 29% and 17% and a specificity of 88% and 95%, respectively, far predicting such a combined event. We observed a marked variation in the positive and negative predictive values of the test in the different time eras and clinical subgroups analyzed. CONCLUSIONS: Our work highlights the importance of associated clinical conditions as determinants of exercise tolerance in patients with HF, and reinforces the importance of proper management of comorbidities to improve functional capacity in these individuals. lt also highlights the need to interpret the prognostic value of the cardiopulmonary stress test differently depending on the clinical characteristics and associated comorbidities of the patient.