Relationship between N-terminal pro-B-type natriuretic peptide (Nt-proBNP) and cardiac cycle efficiency in cardiac surgery.
N-terminal pro-B-type natriuretic peptide (Nt-proBNP) is a peptide released from myocardium in response to ventricular wall stress and dysfunction. Nt-proBNP plasma levels are elevated in a variety of cardiovascular disorders and are largely used for diagnosis and treatment of cardiac diseases. The cardiac cycle efficiency (CCE) is a haemodynamic variable that represents the left ventricle wall stress and the heart's effort to maintain an adequate blood flow to tissues. We investigated the relationship between Nt-proBNP and CCE values in patients undergoing cardiac surgery. Twenty-five patients undergoing aortic valve replacement were studied. Plasma Nt-proBNP concentrations were performed by electroluminescence immunoassay before starting surgery (t0), at the end of extracorporeal circulation (t1) and 3 hours after surgery (t2). CCE measurements were acquired at the same intervals and correlations with Nt-proBNP levels were calculated. Nt-proBNP plasma concentration was 1430 ± 341 pg/ml at t0, peaked significantly at t1 (2129 ± 561 pg/ml, p<0.001) and moderately decreased at t2 (1924 ± 477 pg/ml, p<0.05). A direct correlation between Nt-proBNP measured at t0 and t1 was found (r=0.91, p<0.001). Overall, a negative correlation between CCE and proBNP values was found (r=-0.89, p<0.01). Correlations between CCE and Nt-proBNP were -0.91, -0.83 and -0.88, at t0, t1 and t2, respectively (p<0.01). Nt-proBNP levels reflect the severity of left ventricle dysfunction in patients undergoing cardiac surgery. CCE correlated well with serum Nt-proBNP levels and seems to be a useful variable to monitor the left ventricular stress and recovery during the various phases of surgery.
Scolletta
S
S
Unit of Cardiothoracic Anaesthesia and Intensive Care, Department of Surgery and Bioengineering, University of Siena, Viale Bracci 1, 53100, Siena, Italy. scolletta@unisi.it
Ranaldi
G
G
Carlucci
F
F
Franchi
F
F
Romano
S M
SM
Biagioli
B
B
D000368:Aged; D000465:Algorithms; D001021:Aortic Valve / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000097:blood / Q000503:physiopathology / Q000601:surgery*; D006348:Cardiac Surgical Procedures; D004452:Echocardiography; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods*; D020097:Natriuretic Peptide, Brain / Q000097:blood*; D010446:Peptide Fragments / Q000097:blood*; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology*
D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain