B-type natriuretic peptide and impedance cardiography at the time of routine echocardiography predict subsequent heart failure events.
BACKGROUND
Detection of heart failure (HF) in stable outpatients can be difficult until an overt event occurs. This study sought to determine whether the combination of B-type natriuretic peptide (BNP) and impedance cardiography (ICG) could be used in a nonacute clinical setting to risk stratify and predict HF-related events in stable outpatients.


RESULTS
Patients undergoing routine outpatient echocardiography underwent ICG and BNP testing and were followed for one year for HF-related events (Emergency Department [ED] visit or hospitalization due to HF or all-cause death). A total of 524 patients were analyzed, resulting in 57 HF-related events; 16 ED visits, 17 hospitalizations, and 24 all-cause deaths. Using Cox regression analyses, BNP and systolic time ratio index (STRI) by ICG proved to be the strongest predictors of future HF-related events. Patients with a BNP >100 pg/ml and STRI >0.45 sec(-1) had a significantly lower event-free survival rate than those with a high BNP and low STRI (67% versus 89%, P=.001). In patients with LV dysfunction only, if both BNP and STRI values were high, the relative risk of a HF-related event increased by 12.5 (95 % C.I. 4.2-36.7), when compared with patients with a low BNP and low STRI (P<.001).


CONCLUSIONS
In a nonacute clinical setting, both BNP and ICG testing can provide unique predictive power of long-term HF-related events in a stable cohort of patients with and without LV dysfunction.
Castellanos
Luis R
LR
Division of Cardiology, Department of Medicine Veteran's Affairs San Diego Healthcare System, La Jolla, CA 92161, USA.
Bhalla
Vikas
V
Isakson
Susan
S
Daniels
Lori B
LB
Bhalla
Meenakshi A
MA
Lin
Jeannette P
JP
Clopton
Paul
P
Gardetto
Nancy
N
Hoshino
Max
M
Chiu
Albert
A
Fitzgerald
Robert
R
Maisel
Alan S
AS
D000368:Aged; D002307:Cardiography, Impedance; D015331:Cohort Studies; D016001:Confidence Intervals; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality; D006801:Humans; D008297:Male; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D016019:Survival Analysis; D013997:Time Factors; D018487:Ventricular Dysfunction, Left
D020097:Natriuretic Peptide, Brain