| Objective:The heart failure with normal ejection fraction (HFNEF) has become a highly prevalent medical syndrome, which is characterized by high morbidity and mortality rates. Rapid and accurate diagnosis of this condition is essential for optimizing the therapeutic management. The diagnosis for HFNEF remains unclear up to now, resulting in higher rate of missed diagnosis and misdiagnosis. The HFNEF are characterized more often with elevated left ventricular filling pressure (LVFP), so a definitive diagnosis can be made when the LVFP is elevated. Looking for simple non-invasive indicator of LVFP is significant. Recently, the ratio of the early diastolic transmitral flow velocity by pulsed wave Doppler echocardiography to the early diastolic mitral annular velocity by tissue Doppler imaging (E/E') has been shown to be the most accurate non-invasive predictor of elevated LVFP. Plasma N-terminal pro-brain natriuretic peptide (NT-proBNP) also has been reported to correlate well with LVFP. The research studies suggest that the both seem to be helpful for diagnostic of HFNEF, but the both have low sensitivity or low specificity, neither have been alone adopted in the HFNEF. There are limitations to both, and their diagnostic value in HFNEF are still controversial. The aim of this study was to investigate the value of combing E/E'and NT-proBNP in the diagnosis of HFNEF, and investigated the relationship between E/E'and NT-proBNP levels.Methods:From May 2009 to April 2010, a total of 136 patients (70 women,66 men,44-88 years, mean age 70.2±9.9 y) were enrolled in this study. Among 83 inpatients were selected, with cardiac structural abnormalities or remodeling, who have concomitant cardiovascular disease (such as hypertension, atrial fibrillation, diabetes mellitus, coronary heart disease, hypertrophic cardiomyopathy, etc.). All patients have normal left ventricular ejection fraction (LVEF>50%). All patients were confirmed without following clinical setting:significant valvular heart disease, anemia, hyperthyreosis, renal failure, liver failure, etc.83 inpatients were divided into group 2 and group 3 according to whether HFNEF:group 2 (patients with cardiac disease who have not developed symptomatic heart failure, n=41), group 3 (patients with HFNEF, n=42). Over the same period, 53 cases of healthy persons were selected for the group 1. Group 1 and group 2 which were called as non-HFNEF group together, were comparison of group 3 (HFNEF group). All subjects carried out a comprehensive echocardiography testing (including E/E'). Meanwhile, the plasma NT-proBNP levels were also examined. We compared E/E' and NT-proBNP among the three groups, and analysed the correlation between E/E'and NT-proBNP. The standard used to diagnose the HFNEF were E/E'>15, NT-proBNP>220pg/ml as well the combination of E/E'>15 and NT-pro BNP>220pg/ml, respectively. The both of serial test and parallel test were included in the combination referred to above. According to the three diagnostic standard, the sensitivity, specificity, rate of missed diagnosis, misdiagnosis rate, agreement rate, positive and negative predictive value, positive and negative likelihood ratio were calculated.Results:1. There was no significant difference among three groups in age and sex. And concomitant cardiovascular diseases such as hypertension, atrial fibrillation, diabetes mellitus, coronary heart disease and hypertrophic cardiomyopathy were also no significant difference between group 2 and group 3 (P>0.05).2. All of the echocardiographic parameters except LVEF among the three groups were significantly different. Compared with group 1 and group 2, the left atrial diameter and the level of E significantly increased in group 3, the value of E' peak was significantly low (P<0.05). Compared with group 1, the both of the wall thickness and the left ventricular internal diameter significantly increased in group 2 and group 3 (P<0.05), but the both of the parameters were no difference between group 2 and group 3. The ratio of E/A was significantly lower in group 2 than group 1, but there was no significant change in group 3.3. The value of LnE/E'and LnNT-proBNP were significantly high in group 3, compared with group 1 and group 2 (P<0.05). Compared with group 1, LnNT-proBNP was also high in group 2 (P<0.05), but LnE/E'was no significant difference.4. In all of the patients, there was significant correlation between LnE/E'and LnNT-proBNP (r=0.729, P<0.01). LnE/E'also showed a significant correlation with LnNT-proBNP in group 2 (r=0.364, P<0.05) and group 3 (r=0.447, P<0.01), but showed no correlation in group 1.5. Using the E/E'>15 for judging criteria of HFNEF, sensitivity, specificity, rate of missed diagnosis, misdiagnosis rate, agreement rate, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, were 45.2%,95.7%,54.8%,4.3%,80.1%, 82.6%,79.6%,10.51,0.57, respectively. Using NT-proBNP>220pg/ml for judging criteria, the above of the diagnostic parameters were 85.7%,85.1%, 14.3%,14.9%,85.3%,72.0%,93.0%,5.75,0.17, respectively. Serial test were 45.2%,97.9%,54.8%,2.1%,81.6%,90.5%,80.0%,21.52,0.56, parallel test were 85.7%,83.0%,14.3%,17.0%,83.8%,69.2%,92.9%,5.04, 0.17, respectively.Conclusions:The both of Doppler E/E'and plasma NT-proBNP have been shown to be reliable in diagnostic of HFNEF. The ratio of E/E'>15 has high specificity and positive predictive value, which can increase the accuracy of diagnosis and reduce the misdiagnosis. The plasma NT-proBNP has high sensitivity and negative predictive value, which was interest to aid in the early screening HFNEF and excluding HFNEF. It also can reduce missed diagnosis. There was a significant correlation between the mitral E/E'and the plasma NT-proBNP. Combining of the E/E'and the NT-proBNP can be used more accurately diagnostic HFNEF, specificity, positive predictive value and positive likelihood ratio were best, when use serial test (E/E'>15 and NT-proBNP>220pg/ml) to diagnose HFNEF. Serial test had a highly diagnostic value.
|
PDF Full Text Request