心力衰竭患者脑型利钠肽与心功能和运动呼吸困难程度的关系

目的心力衰竭患者经常有心率增快和舒张功能异常,运动性呼吸困难是许多心脏病患者常见表现,本研究探讨心力衰竭患者血浆脑型利钠肽（BNP）水平与心脏功能参数及呼吸困难严重程度等因素的关系。方法对32例心力衰竭患者（心力衰竭组）进行多普勒超声心动图及血浆BNP和心房利钠肽（ANP）检测,并与30例心功能正常的健康成年人（对照组）的相同指标进行比较。另外,21例患者进行心肺运动试验,观察运动高峰BNP与心肺运动试验VE/VCO2斜率相关性。结果32例心力衰竭患者,其中18例为缺血性心脏病,14例扩张型心肌病,静态心率明显高于正常对照组（P〈0.05）,心力衰竭组左室内径明显增加（P〈0.05）,短轴缩短率明显异常（P〈0.05）。左房内径无明显增加,左室射血距离减低（P〈0.05）,舒张早期充盈速度无明显差别。心力衰竭组BNP水平[（13±11）pmol/L],较对照组[（4.6±2.1）pmol/L]明显增加（P〈0.05）。BNP与ANP水平呈正相关（r=0.73,P〈0.01）。心脏内径大小对BNP和ANP无明显影响。BNP水平与心率、射血时间、充盈时间、E/A比值明显相关,相关系数分别为-0.67、0.71、-0.41、0.62（P均〈0.01）,与左室内径和心房内径无相关性。ANP水平只与E/A比值高度相关（r=0.55,P〈0.05）。运动高峰BNP浓度与VE/VCO2斜率正相关（r=0.70,P〈0.01）。结论在心力衰竭患者中,血浆BNP水平能较好地反映心力衰竭患者的多普勒超声心动图心功能参数及运动呼吸困难程度的状况。

Brain natriuretic peptide in patients with heart failure:relation with left ventricular function and exercise breathness severity

Objective Rapid heart rate and diastolic dysfunction are common in patients with early stage of heart failure. Exercise breathness is main symptom in such patients. Atrial natriuretic peptide（ANP） is a cardiac hormon that secreated by increased atrial stretch. Positive correlation between plasma ANP concentrations and atrial pressures have been found in cardiac patients and healthy subjects. Brain natriuretic peptide （BNP） is released primarily in respons to ventricular wall stress. The aim of this study ,therefore ,was to determine the left ventricular ejection and filling function associated with higher ANP and BNP levels in patients with heart failure and to correlate exercise BNP with VE/VCO2 slop assessed by cardiopulmonary exercise test. Methods 30 normal subjects and 32 patients underwent complete m-mode and cross sectional echocardiography and Doppler ultrasound examination. Aortic flow velocity and diastolic flow velocity was recorded by pulsed wave Doppler. The following diastolic variables were measured： peak left ventricular ejection time and filling time and velocity. Peak early mitral filling velocity （ E wave ）, peak atrial filling velocity （A wave） and left ventricular filling time, E/A ratio were derived. ANP and BNP were assessed by radioimmunoassy at same time. Results In 32 patients with heart failure, 18 patients had ischemic heart disease, 14 patients had nonischemic heart disease. Resting heart rate in patients with heart failure were higher than normal subjects （ P 〈 0. 05 ）. Compared with normal subjects, left ventricular dimension increased（ P 〈 0. 05 ） and shortening fraction reduced （ P 〈 0. 05 ） , stroke distance reduced （ P 〈 0. 05 ）. Early diastolic filling velocity did not show significant difference（ P 〉 0. 05 ）. 2. ANP significantly correlated with BNP in patients with heart failure （ r = 0.73, P 〈 0. 01 ）, There are no significant difference between end-diastolic dimension 〉 6. 5 cm and end-diastolic dimension 〈 6. 5 cm in both ANP and BNP concentration （ P 〉 0. 05 ）. 3. Resting heart rate correlated with BNP （ r = - 0. 67, P 〈 0. 01 ）. BNP did not correlate with left ventricular size and atrial size. But significant correlated with left ventrieular ejection time （r = 0. 71, P 〈0.01） and filling time（r = -0.41,P〈0.01） as well as E/A ratio（r =0.62,P〈0.01）. ANP only correlated with E/A ratio（ r = 0. 55,P 〈 0. 01 ）. 4. Exercise BNP correlated with VE/VCO2 slop （ r = 0. 70, P 〈 0. 01 ） by cardiopulmonary exercise test. Conclusions ANP and BNP were elevated in early stage heart failure patients due to ischemic heart disease and dilated cradiomyopathy, significant correlated with cardiac function by Doppler echocardiogram. Exercise BNP related with VE/VCO2 slop in cardiopulmonary exercise test in such patients.