Hemodynamic correlates of atrial natriuretic peptide concentration in unselected patients with heart disease of different etiologies.
BACKGROUND
Although a large number of studies have investigated the relationship between atrial natriuretic peptide (ANP) concentrations and circulatory abnormalities, it is presently unsettled as to whether this parameter provides valuable information in unselected patients with heart disease of different etiologies regardless of the presence of left ventricular dysfunction or heart failure.


OBJECTIVE
The aim was to evaluate the correlation between ANP, hemodynamics and parameters of ventricular function in a large series of consecutive patients and to define the predictive value of ANP for the identification of specific circulatory abnormalities.


METHODS
Cardiac catheterization was performed in 167 consecutive patients (62% males; mean age 62 yrs; range 18-85) and ANP serum levels were determined concomitantly by single antibody immune assay. Underlying etiology was: ischemic (67), valvular (72), idiopathic (12) and miscellaneous (16). Data management included: comparison of patients according to ANP values > or < 50% percentile of the cumulative distribution curve (i.e. 140 pg/ml); analysis of ANP concentrations according to the presence of normal or abnormal ventricular filling pressures; correlation between hemodynamic parameters and ANP concentrations; correlation of ANP with ventricular function in the whole population and in subgroups; calculation of sensitivity and specificity of ANP for the identification of abnormal filling pressures.


RESULTS
Mean ANP concentration was 181 +/- 139 pg/ml. Patients with ANP < 140 had significantly lower right-sided pressures but similar ventricular volumes and ejection fractions. By multivariate analysis, the single independent predictor of ANP was wedge pressure (p < 0.0001). Regarding etiology, severe mitral regurgitation was associated with the highest ANP levels (259 +/- 122 pg/ml), although the difference was not significant. The presence of abnormal left and right ventricular filling pressures was associated with significantly higher levels of ANP (p < 0.0001). A level of 125 pg/ml proved to be fairly sensitive (79%) but poorly specific (66%) for the detection of an abnormal wedge pressure. ANP was related to ventricular function only in the small subgroup of patients with dilated cardiomyopathy, where a significant negative correlation was found with both left ventricular (r = -0.72; p = 0.008) and right ventricular ejection fraction (-0.71; p = 0.01).


CONCLUSIONS
In unselected cardiac patients, ANP is confirmed to be a marker of left ventricular filling pressure in spite of poor specificity. Ventricular function appears to be related to ANP concentrations only in the subgroup of patients with pure heart-muscle disease.
La Vecchia
L
L
Divisione di Cardiologia, Ospedale Civile S. Bortolo, Vicenza.
Fortunato
A
A
Varotto
L
L
Bonanno
C
C
Paccanaro
M
M
Ometto
R
R
Vincenzi
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D009320:Atrial Natriuretic Factor / Q000097:blood*; D006328:Cardiac Catheterization / Q000379:methods / Q000706:statistics & numerical data; D017023:Coronary Angiography; D005260:Female; D006331:Heart Diseases / Q000097:blood* / Q000175:diagnosis / Q000503:physiopathology*; D006439:Hemodynamics; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric
D009320:Atrial Natriuretic Factor