Correlation Study Of Cardiopulmonary Exercise Test Parameters With NT-proBNP And MR-proANP In Heart Failure With Preserved Ejection Fraction Patients

Background:Heart failure with preserved ejection fraction(HFpEF)has an insidious and diverse etiology,and its main clinical feature is left ventricular diastolic dysfunction.However,the pathophysiology and pathogenesis of HFpEF are still unclear,and its morbidity and mortality are still on the rise.Cardiopulmonary exercise test(CPET)can quantitatively and objectively evaluate cardiopulmonary reserve function,and exercise endurance through real-time monitoring of the dynamic changes of oxygen consumption and carbon dioxide output of the body during exercise.It is the gold standard for evaluating cardiac function in patients with heart failure.Compared with traditional exercise tests,CPET provides a comprehensive assessment of the lung,cardiovascular,muscle,and cellular oxidation systems involved.Brain natriuretic Peptide(BNP)and N-terminal pro-Brain natriuretic Peptide(NT-proBNP)is widely used in clinical markers of heart failure,usually in the ventricular pressure and ventricular volume load increases secretion of such cases,not only has high diagnostic value in clinic,and can also be used to evaluate the severity and prognosis of heart failure.Atrial natriuretic peptide(ANP)is secreted by atrial myocytes and released into the peripheral blood when the atria are pulled.As an intermediate fragment of its precursor,midregional pro-atrial natriuretic peptide(MR-proANP)can accurately reflect the production of ANP and has good stability.MR-proANP is an emerging marker of heart failure that has been deeply studied in recent years.Recent studies have found that MR-proANP is better than NT-proBNP in the diagnosis,disease assessment and prognosis of HFpEF,and has higher clinical application value.In clinical work,we recommend patients with heart failure to assess their cardiopulmonary function through CPET,so as to accurately stratify their risk and develop individualized exercise prescriptions.However,currently,CPET has high requirements and is difficult to be popularized,and some patients with heart failure cannot tolerate the test due to their own conditions.With the deepening of research in recent years,It was found that NT-proBNP was significantly correlated with CPET core parameters and was an independent predictor.MR-proANP as more emerging markers of heart failure in recent years,the application in HFpEF value superior to the NT-proBNP,but the correlation between CPET parameters and has not yet been reported,so in this study,we analyzed the HFpEF CPET core parameters of the patients and the NT-proBNP,MR-proANP correlation,aimed to find an easy for cardiopulmonary function and a valuable serum marker to predict the extent of the damage,simplify and optimize the process of clinical decision making..Objective:This study intends to evaluate the exercise endurance and cardiopulmonary function status of HFpEF patients through CPET,and to explore the correlation between NT-proBNP,MR-proANP and CPET core indexes of HFpEF patients.MR-proANP is expected to be a serum indicator to predict the cardiopulmonary function of HFpEF patients,so as to more accurately assess the condition and formulate treatment strategies.Methods:We choice 61 patients with HFpEF(HFpEF group)in The Fifth Affiliated Hospital of Zhengzhou University from August 2018 to December 2019,and we choice 43 volunteers(control group)and the age,sex,body mass index that matches over the same period in our hospital.All enrolled patients underwent CPET,and the plasma was collected at rest and the content of MR-proANP and NT-proBNP was detected.we analyzed the correlation between NT-proBNP and MR-proANP levels and CPET core parameters.According to the New York Heart Association(NYHA),we put HFpEF group divided into two subgroups,named the NYHA Ⅱ group and NYHA Ⅲ subgroup,including 27 patients of NYHAⅡ group,34 patients with NYHAⅢ group,compared between the two subgroups of cardiopulmonary function and plasma of MR-proANP,、NT-proBNP level difference.Results:In HFpEF group,The results of CPET showed that AT(mL/min,mL·kg-1.min-1和%pred)、PeakVO2(mL/min,mL·kg-1.min-1 and%pred)and peak heart rate,diastolic blood pressure,exercise time were significantly lower than the control group,VE/VCO2Slope were higher than control group,The differences were statistically significant(P<0.05).There was no significant difference in other indicators(P>0.05).In HFpEF group,NYHAII subgroup of patients with AT(mL/min,mL·kg-1·min-1 and%Pred),PeakVO2(mL/min,mL·kg-1·min-1 and%Pred)were higher than NYHAⅢ subgroup,VE/VCO2Slope were lower,the difference was statistically significant(P<0.05),the rest of the indicators there was no statistically significant difference between the two subgroups(P>0.05).By Pearson correlation analysis,in HFpEF group,PeakVO2 was negatively correlated with the NT-proBNP(r=0.529,P<0.05),MR-proANP(r=0.564,P<0.05)and NYHA classification(r=-0.533p<0.05)and were not correlated with age,、BMI,、peak heart rate、peak systolic blood pressure and peak diastolic blood pressure(P>0.05).The VE/VCO2 Slope of HFpEF group was negatively correlated with the NT-proBNP(r=0.540,P<0.05),MR-proANP(r=0.422,P<0.05),and NYHA(r=0.397,P<0.05),and was not correlated with age、BMI、peak heart rate、peak systolic blood pressure and peak diastolic blood pressure(P>0.05).Multiple linear regression analysis showed that NT-proBNP and MR-proANP were independent predictors of PeakVO2 and VE/VCO2Slopes(P<0.05).ROC curve showed that NT-proBNP and MR-proANP had certain value in predicting PeakVO2(mL·kg-1·min-1)<20,<14 and VE/VCO2Slpoe>34(P<0.05).Conclusions:1.The exercise tolerance and cardiopulmonary function of HFpEF patients were decreased,and the cardiopulmonary function of HFpEF groups with NYHA grades was different,NYHA grade of HFpEF patients is inversely proportional to cardiopulmonary function,CPET core index more accurately,comprehensively reflect HFpEF patients heart function damage degree.2.The PeakVO2 and VE/VCO2Slopes of HFpEF patients are significantly correlated with NT-proBNP and MR-proANP.The increased plasma levels of NT-proBNP and MR-proANP are independent predictors of cardiopulmonary function decline in HFpEF patients.It is of great clinical value to indirectly predict the cardiopulmonary function through the easily obtained blood biochemical indexes,which provides a new perspective for the clinical management of HFpEF patients.