High plasma brain natriuretic polypeptide level as a marker of risk for thromboembolism in patients with nonvalvular atrial fibrillation.
OBJECTIVE
Assessment of left atrial appendage (LAA) function with transesophageal echocardiography is useful for detecting patients at high risk for thromboembolism as a result of atrial fibrillation (AF). A recent study reported that the atrium is the main source of brain natriuretic polypeptide (BNP) in AF patients without overt heart failure. The purpose of this study was to assess a possible relationship between LAA function and plasma BNP levels in nonvalvular AF.


METHODS
Thirty-four consecutive patients with chronic nonvalvular AF (age, 69+/-9 years) underwent transesophageal echocardiography and plasma BNP measurement. Thirteen patients with a history of thromboembolism or echocardiographic evidence of thrombus (E + group) were compared with 21 AF patients without complications (E- group).


RESULTS
The E+ group patients demonstrated greater impairment of LAA velocity and higher plasma BNP levels than the E- group patients (LAA velocity: 12+/-6 versus 31+/-17 cm/s, P<0.05; plasma BNP: 126+/-53 versus 86+/-45 ng/L, P<0.05). Overall analysis of the continuous variables with multiple logistic regression analysis revealed that BNP was a significant predictor of thromboembolism. There was a weak but significant negative correlation between plasma BNP levels and LAA flow velocity (r=0.38, P<0.05). No intergroup difference in plasma atrial natriuretic polypeptide levels was found.


CONCLUSIONS
The present data suggest the usefulness of measuring plasma BNP levels, which may reflect augmented atrial secretion of BNP from the impaired atrial myocardium, in detecting patients at high risk for thromboembolic complications in nonvalvular AF.
Shimizu
Hiromi
H
Fourth Department of Internal Medicine, Shimane Medical University, Shimane, Japan.
Murakami
Yo
Y
Inoue
Shin-ichi
S
Ohta
Yoko
Y
Nakamura
Ko
K
Katoh
Harumi
H
Sakne
Takeshi
T
Takahashi
Nobuyuki
N
Ohata
Shuzo
S
Sugamori
Takashi
T
Ishibashi
Yutaka
Y
Shimada
Toshio
T
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020517:Atrial Appendage / Q000000981:diagnostic imaging / Q000503:physiopathology; D001281:Atrial Fibrillation / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D016279:Atrial Function, Left; D009320:Atrial Natriuretic Factor / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001783:Blood Flow Velocity; D002908:Chronic Disease; D017548:Echocardiography, Transesophageal; D004562:Electrocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism; D020097:Natriuretic Peptide, Brain / Q000097:blood* / Q000378:metabolism; D011237:Predictive Value of Tests; D018570:Risk Assessment; D013923:Thromboembolism / Q000097:blood* / Q000175:diagnosis / Q000209:etiology*
D015415:Biomarkers; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor