| BackgroundChronic heart failure has become an important public problem which is a serious threat to human health. According to the left ventricular systolic function is normal or not, heart failure can be divided into two kinds:systolic heart failure (SHF) and diastolic heart failure (DHF). Both of the etiology, pathogenesis, treatment and prognosis of them are different, but the signs and symptoms of both are very similar. It is very difficult to identify the two kinds of heart failure only by clinical symptoms. Therefore finding objective, quick, accurate indexes to guide the diagnosis and treatment of heart failure is in great need in the clinical work.Electrocardiogram is one of the conventional check in patients with chronic heart when admitted to hospital. The QRS complex duration reflect the depolarization functions of left and right ventricles, which are correlated with left ventricular quality, end-diastolic diameter and wall thickness positively. Patients with chronic heart failure will have QRS complex duration changed due to worse cardiac function, myocardial ischemia, increased tension on ventricular wall,which will affect the transmission systems and bipolar effect of heart. Plasma N-terminal pro B-type natriuretic peptide (NT-proBNP) is mainly synthetized and secreted by the ventricle muscle cell. Its main effect is natriuretic diuresis, the dilation of blood vessels and reducing cardiac load. The synthesis and secretion are regulated according to the tension of ventricular wall. So it can be used to judge the severity of heart failure, but is not an independent index for the judgment of the types of chronic heart failure.ObjectiveTo determinate electrocardiogram QRS complex duration, plasma NT-proBNP level and related echocardiography indexes in patients with different clinical phenotypes of chronic heart failure and to explore the correlation of electrocardiogram QRS complex duration, plasma N-terminal-pro-brain natriuretic peptide (NT-proBNP), left ventricular ejection fraction (LVEF) and left ventricular end-diastolic dimension(LVEDd) in patients with SHE To further evaluate clinical value of measuring QRS complex duration and plasma NT-proBNP at the same time so as to offer information for the diagnosis and differential diagnosis of chronic heart failure.Methods162patients with chronic heart failure were divided into two groups according to left ventricular ejection fraction(LVEF):systolic heart failure group(SHF group, LVEF≤45%, n=75) and diastolic heart failure group(DHF group, LVEF>45%, n=87).Datas of electrocardiogram QRS complex duration, plasma NT-proBNP, LVEF and LVEDd were obtained and compared in162patients with chronic heart failure and63normal control subjects. The correlation analysis was made between QRS complex duration and plasma NT-proBNP, LVEF and LVEDd respectively in SHF group.Resultsl.The QRS complex duration was significantly increased in patients in SHF group (138.20+2.55)ms than that in DHF group (100.93+27.13)ms, P<0.05or control group(80.56+7.76)ms, P<0.05.2. Plasma level of NT-proBNP was (1446.01+26.03)pg/ml in SHF group and (664.07+35.75)pg/ml in DHF group, which were both significantly higher than the control group(104.96+47.84)pg/ml，P<0.01and plasma level of NT-proBNP was significantly higher in SHF group than that in DHF group(P<0.01).3. The QRS complex duration was correlated positively with plasma levels of NT-proBNP and LVEDd (r=0.776,0.869，P<0.01) and was correlated negatively with LVEF(r=-0.917，P<0.01) in SHF group.Conclusion1. In patients with chronic heart failure, patients with systolic heart failure have longer QRS complex duration than patients with diastolic heart failure; QRS complex duration has correlation with left ventricular systolic function, the wider QRS complex is, the more worse the systolic function does the left ventricular has, and the more worse the prognosis is.2. QRS complex duration is significantly correlated with plasma NT-proBNP, LVEF and LVEDd in patients with chronic heart failure. As QRS complex duration was prolonged, the level of plasma NT-proBNP increased, LVEF decreased while LVEDd gradually increased.3. QRS complex duration indicates to be an effective biological parameter for assessing different types of heart dysfunction in CHF and it is of guiding significance for medicine application when combined with the measurement of plasma NT-proBNP. |
