Clinical utility of B-type natriuretic peptide for estimating left ventricular filling pressures in unselected elderly patients undergoing diagnostic coronary angiography.
BACKGROUND
B-type natriuretic peptide (BNP) and echocardiographic tissue Doppler indices (TDI) predict elevated filling pressures, but few data exist comparing these methods while adjusting for clinical variables. We hypothesized that BNP would provide incremental value for estimating left ventricular end-diastolic pressure (LVEDP).


METHODS
Clinical data, echocardiograms, and BNP levels were obtained in 182 geriatric patients undergoing diagnostic left-heart catheterization. Patients with severe valvular disease or acute myocardial infarction were excluded. LVEDP and standard echocardiographic measurements, including early (E) and late (A) mitral inflow velocities and early (Em) mitral annular velocities by TDI, were measured in blinded fashion.


RESULTS
Mean age was 71 years, 51% were female, and 19% were nonwhite. Univariate correlations with LVEDP (p < or = 0.05) included functional class, beta-blocker use, body-mass index (BMI), heart rate, blood urea nitrogen (BUN), hemoglobin, peak tricuspid regurgitation velocity, left atrial volume index, E/A ratio, deceleration time, septal E/Em ratio and BNP. Linear regression analysis revealed independent correlations of LVEDP with BMI (p = 0.002), BUN (p = 0.011), and E/A ratio (p < 0.001). After adjusting for these variables, BNP was an independent correlate of LVEDP (p = 0.001). Predictors of LVEDP > or = 20 mmHg by logistic regression included higher BMI (p = 0.002), lower heart rate (p = 0.042), and septal E/Em ratio < 15 (p = 0.023). BNP was an independent predictor of LVEDP > or = 20 mmHg after adjustment for these variables (p = 0.037, c-statistic 0.663).


CONCLUSIONS
Standard clinical variables offer only modest utility for predicting LV filling pressures. BNP provides incremental value for estimating LVEDP, and elevated BNP is an independent predictor of increased LVEDP among older patients undergoing diagnostic cardiac catheterization.
Stolker
Joshua M
JM
Mid America Heart Institute of Saint Luke's Hospital, 4401 Wornall Road, Kansas City, MO 64111, USA. jstolker@yahoo.com
Rich
Michael W
MW
D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D015992:Body Mass Index; D017023:Coronary Angiography; D003971:Diastole / Q000502:physiology*; D015150:Echocardiography, Doppler; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000502:physiology; D009200:Myocardial Contraction / Q000502:physiology*; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D012039:Regional Blood Flow / Q000502:physiology; D012044:Regression Analysis; D015203:Reproducibility of Results; D016277:Ventricular Function, Left / Q000502:physiology*
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain