Objective: We aimed to investigate the value of N-terminal pro-Brain Natriuretic Peptide (NT-proBNP) in combination with tissue Doppler imaging (TDI) to predict the presence of significant coronary artery (CAD) in patients with conventionally normal systolic and diastolic function.
Methods: Plasma NT-proBNP concentrations were measured in 87 patients who had been referred to coronary angiography with stable anginal symptoms, and preserved systolic and diastolic LV function in conventional echocardiography. Regional diastolic function was additionally assessed by TDI in all patients. Patients were then divided into 2 groups according to having normal or abnormal diastolic function with TDI. Group 1 had preserved diastolic function with conventional and TDI methods. Group 2 had conventionally normal function and abnormal regional function with TDI. Groups were divided into 2 subgroups according to the cut-off NT-proBNP value of 100 pg/ml. Coronary artery disease was classified as 0 (absence of >70% diameter stenosis in any coronary artery), 1, 2 or 3 vessel disease (with lesions >70%).
Results: The NT-proBNP levels were positively correlated with the number of coronary vessels involved. There was statistically significant difference between 0-2, 0-3, 1-3 vessels involvement, but no significant difference between 0-1, 1-2, 2-3 vessels involvement. In group 1 all patients with plasma NT-proBNP levels >100 pg/ml had severe CAD (p=0.003). But in group 2 only 60% of patients with NT-proBNP>100 pg/ml had severe CAD.
Conclusion: In patients with stable angina who have normal systolic and diastolic function, NT-proBNP is useful to predict the angiographic severity of CAD. In patients with unimpaired regional diastolic function, NT-proBNP may be valuable to predict the presence of severe CAD in stable angina.