Cardiopulmonary Exercise Testing In Patients With Heart Failure–normal Ejection Fraction

[Objective] To assess the clinical and predictive value of cardiopulmonary exercise testing(CPET) used in heart failure with normal left ventricular ejection fraction(HFNEF) to evaluate exercise tolerance. [Methods] A total of 82 patients were enrolled in this sudy. Among them, 41 patients were normal heart function as control group and 41 were diagnosed as HFNEF as HFNEF group. CPET and UCG(ultrasonic cardiogram) indicators were collected in the third day after admission. Person's and pattial correlations were used to perform to compare CPET and UCG.[Results] The age, gender, coronary heart disease, diabetes, smoking, drug use(angiotensin converting enzyme inhibitors ACEI, ?-blocker), body mass index(BMI) and serum creatinine levels at baseline were similar between exercise group and non-exercise group(P>0.05). Compared with the control group.the HFNEF group showed a lower peak oxygen uptake(Peak VO2)(26.66±7.88 VS 22.39±5.35,P=0.029), carbon dioxide production(VCO2)(1.77±0.64 VS 1.52±0.42,P=0.044), oxygen uptake at anaerobic threshold(AT)(1.33±0.50 VS 1.11±0.30,P=0.021), and a higher minute ventilation/carbon dioxide production(VE/VCO2)(30.54±4.47 VS 32.54±4.37,P=0.043). The difference of peak rate(HR Peak), end-tidal carbon dioxide(PET CO2) and respiratory exchange ratio(RER) was not statistically significant. Pearson correlation revealed that mitral peak velocity of early filling/ early diastolic mitral annular velocity( E/E',10.141±2.05) was significantly correlated with peak oxygen uptake[Peak VO2,(24.15±8.31)ml/kg/min](r=-0.287,P=0.046), carbon dioxide production [VCO2,(1.63±0.51)l/min](r=-0.429,P=0.002),partial pressure of end-tidal carbon dioxide [PET CO2,(39.50±7.77)mm Hg]( r=-0.282, P=0.050), minute ventilation/carbon dioxide production(VE/VCO2,31.69±5.32)(r=0.411,P=0.003). Early diastolic mitral annular velocity[E',(6.46±1.60)cm/s] was relevant to Peak VO2(r=0.351,P=0.013),VCO2(r=0.452,P=0.001),Peak VO2(r=0.310,P=0.013),VE/VCO2(r=-0.434,P=0.002),respiratory exchange ratio(RER,1.18±0.13)(r=0.350,P=0.014). After adjustment, partial correlation revealed that VCO2 was significantly correlated with E / E'(r =-0.322, P = 0.043) and E 'peak(r = 0.385, P= 0.014). VE/VCO2 was relevant to E / E '(r = 0.389, P = 0.013) and E' peak related(r =-0 331, P = 0.037). VO2 peak was significantly correlated wiht EF(r =-0.407,P = 0.009), ESV(r = 0.392, P = 0.012) and LVDS(r = 0.365, P = 0.021) related. [Conclusion] Exercise tolerance in HFNEF patients has limited. For HFNFE patients,CPET has high values of assessment and prognosis.