Kälsch Hagen, Neumann Till, Erbel Raimund
Int J Cardiol. 2009 Mar 20;133(1):e22-4. doi: 10.1016/j.ijcard.2007.08.098. Epub 2008 Feb 21.
Plasma brain natriuretic peptide (BNP) is a useful adjunct to diagnose and monitor patient with heart failure, but there are comorbidities such as chronic kidney disease or chronic pulmonary disease, which influence the interpretation of BNP levels.
We present a case of a young and very obese patient (body mass index [BMI] 72.6 kg/m(2)), who was presented with acute global heart decompensation. Echocardiography revealed a dilated left ventricle with an ejection fraction of 20% by global distributed heart with enlarged right heart caves. Computed tomography and X-ray demonstrated an extreme cardiomegaly with cardio-thoracic ratio of 0.71. Remarkably, laboratory measurements revealed only a slight elevated concentrations of brain natriuretic peptide (BNP) (443.2 pg/ml) and his inactive component NT-proBNP (1710 pg/ml). Despite maximized heart care clinical condition of the patient aggravated continuously so that the patient died after 6 days because of heart insufficiency.
Obese patients (body mass index [BMI] >30 kg/m(2)) with any given severity of heart failure obviously express lower levels of BNP. Until now, the cause for this phenomenon is unclear. Therefore caution should be exercised in interpreting BNP levels in such patients.
血浆脑钠肽（BNP）是诊断和监测心力衰竭患者的有用辅助指标，但存在慢性肾病或慢性肺病等合并症时，会影响对BNP水平的解读。
我们报告一例年轻且极度肥胖的患者（体重指数[BMI]为72.6kg/m²），该患者出现急性全心功能不全。超声心动图显示左心室扩张，全心整体分布的射血分数为20%，右心腔扩大。计算机断层扫描和X线显示心脏极度增大，心胸比为0.71。值得注意的是，实验室检查仅显示脑钠肽（BNP）浓度略有升高（443.2pg/ml），其无活性成分NT-proBNP为（1710pg/ml）。尽管给予了最大程度的心脏护理，患者的临床状况仍持续恶化，最终在6天后因心力衰竭死亡。
患有任何给定严重程度心力衰竭的肥胖患者（体重指数[BMI]>30kg/m²）明显表现出较低水平的BNP。迄今为止，这种现象的原因尚不清楚。因此，对此类患者BNP水平的解读应谨慎。
