The Research Of Glomerular Filtration Rate Level In Heart Failure Patients And Its Influential Factors

Reserch backgroundChronic heart failure (CHF) is a severe clinical syndrome, it is not only for the heart pump function decline, also accompanied by kidneys, lungs, liver and other organs dysfunction. In the initial stage of CHF, there is neurohormonal-mediated myocardial remodeling, and the heart pump function is still capable of compensation, along with the progress of the disease, the pump function decompensated, and heart failure symptoms come. Reduced cardiac output leading to decreased renal blood flow, decreased glomerular filtration rate and renal dysfunction. Between the heart and kidney, there are pathological physiological changes which affect each other, neurohormonal and renin-angiotensin-aldosterone system activate as the central link, form a vicious cycle. Therefore, early detection and treatment of other organs' anomaly accompanied with heart failure, can play an active role for improving the prognosis of heart failure.Recently, lots of studies have pointed out that renal insufficiency can be used as an independent risk factor for cardiovascular disease, impaired renal function of patients may be prompted to aggravation of heart failure. glomerular filtration rate is the best indicator of renal function for accurate assessment of renal function, which have important clinical significance. There are many ways for measuring GFR. The determination of inulin clearance rate is the best way to estimate glomerular filtration rate, but it's not suitable for clinical use, only suitable for scientific research. Radionuclide glomerular filtration rate can be determined accurately, which reflect the glomerular filtration rate accurately, but the price is expensive, not suitable for clinical screening and repeated measurement, and also not suitable for pregnant and lactating women. The convenient formula for estimating glomerular filtration rate are MDRD formula, simplified MDRD formula, Cockcroft-Gault formula and formula based on Cystatin C (Cys c). At present, there are quite a number of clinical researches on the glomerular filtration rate in patients with heart failure in foreign countries, but there is only few report of the relationship between glomerular filtration rate and different cardiac function, In this research, we analyzed and discussed the relationship between glomerular filtration rate and different cardiac function(647 cases of heart failure patients).Object647 patients with heart failure were divided into 2 groups, acute heart failure group(18 patients) and chronic heart failure group(629 patients),629 CHF patients were divided into 4 groups according to the New York Heart Association (NYHA) criteria, The number of NYHAⅠ-Ⅳwas 236,138,132,59 respectively,54 patients who did not have heart failure were involved as control group. we calculated the glomerular filtration rate by MDRD formula, simplified MDRD formula, Cockcroft-Gault formula and formula based on Cystatin C (Cys c), analyzed and discussed the relationship between glomerular filtration rate and different cardiac function and the relationship between glomerular filtration rate and left ventricular ejection fraction(LVEF), N-terminal pro-brain natriuretic peptide(NT-proBNP), C-reactive protein(CRP), uric acid(UA).MethodsCollect the information of CHF patients and control group patients.647 patients with heart failure were divided into 2 groups, acute heart failure group(18 patients) and chronic heart failure group(629 patients),629 CHF patients were divided into 4 groups according to the New York Heart Association (NYHA) criteria, The number of NYHAⅠ-Ⅳwas 236,138,132,59 respectively,54 patients who did not have heart failure were involved as control group. we calculated the glomerular filtration rate by MDRD formula, simplified MDRD formula, Cockcroft-Gault formula and formula based on Cystatin C (Cys c), and examine the level of left ventricular ejection fraction(LVEF), N-terminal pro-brain natriuretic peptide(NT-proBNP), C-reactive protein(CRP), uric acid(UA), serum creatinine(Scr), Blood Urea Nitrogen(Bun), albumin(Alb), Cystatin C (Cys c).The formula we commonly used in clinic includes:(1) MDRD formula: GFR=170×Scr-0.999×age-0.0176×bun-0.170×alb0.318×(0.762 female); (2) simplified MDRD formula:GFR=186.3×(Scr)-1.154×(age)-0.203×(0.742 female)。(3) Cockcroft-Gault formula:GFR=Ccr×0.84×1.73/BSA; Ccr=[(140-age)×weight(kg)×(0.85 female)]/(72×Scr); BSA=0.007184 X weight0.425×height0.725. (4) formula based on Cystatin C (Cys c):GFR=66.8 X Cys c-1.30。The unit in formulas above:GFR (ml/min·1.73m2),age(year),weight(kg) height (cm),Scr(mg/dl),bun(mg/dl),alb(g/dl),Cys c (mg/l)。A statistical software package(SPSS 13.0) were employed for data analyze. All data were showed ad mean±standard deviation(x±s). Means between two groups were compared by two-independent sample t-test. Means among groups were analyzed by one-way ANOVA. After the Levene test of homogeneity of variance, if the homogeneity of variance of data was well, LSD test was applied for inner-group, if the homogeneity of variance of data was not well, Dunett test was applied for inner-group. The correlation between two normal distribution measurement data was showed by Pearson correlation. The difference was statistically significant if P <0.05.Resultsl.The relationship between heart function and GFR estimated by simplified MDRD formulaThe GFR estimated by simplified MDRD formula decreased in control group, NYHAⅡgroup, NYHAⅠgroup, NYHAⅢgroup, NYHAⅣgroup and acute heart failure group gradually. There is significant difference between NYHAⅠ group and acute heart failure group, control group. There is significant difference between NYHAⅡgroup and NYHAⅢgroup, NYHAⅣgroup, control group. There is significant difference between NYHAⅢgroup and control group. There is significant difference between NYHAⅣgroup and control group. There is significant difference between acute heart failure group and control group (P <0.05). There is no significant difference among other groups.2. The relationship between heart function and GFR estimated by MDRD formulaThe GFR estimated by MDRD formula decreased in control group, NYHAⅡgroup, NYHAⅠgroup, NYHAⅢgroup, NYHAⅣgroup and acute heart failure group gradually. There is significant difference between NYHAⅠgroup and NYHAⅢgroup, NYHAⅣgroup,acute heart failure group. There is significant difference between NYHAⅡgroup and NYHAⅢgroup, NYHA IV group, acute heart failure group, control group. There is significant difference between NYHAⅢgroup and NYHA IV group, control group. There is significant difference between NYHA IV group and control group. There is significant difference between acute heart failure group and control group (P<0.05). There is no significant difference among other groups.3. The relationship between heart function and GFR estimated by Cockcroft-Gault formulaThe GFR estimated by Cockcroft-Gault formula decreased in control group, acute heart failure group, NYHAⅡgroup, NYHAⅠgroup, NYHAⅣgroup and NYHAⅢgroup gradually. There is significant difference between NYHAⅡgroup and NYHAⅢgroup, NYHA IV group. There is significant difference between NYHAⅢgroup and control group. There is significant difference between NYHAⅣgroup and control group. There is no significant difference among other groups.4. The relationship between heart function and GFR estimated by formula based on Cystatin C The GFR estimated by formula based on Cystatin C decreased in control group, NYHAⅡgroup, NYHAⅠgroup, NYHAⅢgroup, NYHAⅣgroup and acute heart failure group gradually. There is significant difference between NYHAⅡgroup and NYHAⅢgroup, NYHA IV group. There is significant difference between NYHAⅢgroup and control group. There is significant difference between NYHAⅣgroup and control group. There is significant difference between acute heart failure group and control group. There is no significant difference among other groups.5.The correlation among formulasPearson correlation test showed that, eGFR(sMDRD) with eGFR(MDRD), eGFR(Cockcroft-Gault) and eGFR(Cys c) had positive correlations(r=0.965,0.886, 0.727 respectively, P<0.001). eGFR(MDRD) with eGFR(Cockcroft-Gault) and eGFR(Cys c) had positive correlations(r=0.895,0.731 respectively, P<0.001). eGFR(Cockcroft-Gault) and eGFR(Cys c) had positive correlations. (r=0.708, P <0.001).6. The correlation between NT-proBNP and GFRPearson correlation test showed that, NT-proBNP with eGFR(sMDRD), eGFR(MDRD), and eGFR(Cockcroft-Gault) had negative correlations(r=-0.307,-0.381,-0.308 respectively, P<0.001).7. The correlation between LVEF and GFRPearson correlation test showed that, LVEF with eGFR(sMDRD), eGFR(MDRD) and eGFR(Cockcroft-Gault) had positive correlations(r=0.109,0.140,0.180 respectively, P<0.05).8. The correlation between UA and GFRPearson correlation test showed that, UA with eGFR(sMDRD), eGFR(MDRD), eGFR(Cockcroft-Gault) and eGFR(Cys c) had negative correlations(r=-0.315,-0.400,-0.383,-0.295 respectively, P<0.001).9. The correlation between CRP and GFRPearson correlation test showed that, CRP with eGFR(sMDRD), eGFR(MDRD) and eGFR(Cockcroft-Gault) had negative correlations(r=-0.167,-0.206,-0.240 respectively,P<0.05).10.The GFR between normal LVEF CHF patients and low LVEF CHF patientsThere is no significant difference between two group.(74.47±30.49 ml/min·1.73m2 vs.70.77±8.11 ml/min·1.73m2,P=0.251)Cnclusion1.The eGFR is lower in CHF patients than that in control group, and it shows a decreasing trend with the increase of heart function classification.2.The GFR estimated by four formulas shows positive correlation with each other.3.The eGFR in CHF patients has negative correlation with NT-proBNP, UA and CRP, has positive correlation with LVEF.4. The eGFR level had no significant difference between normal LVEF CHF patients and low LVEF CHF patients.