Antithrombin after cardiac surgery: implications on short and mid-term outcome.
BACKGROUND
Antithrombin (AT) drop during cardiac surgery has been described. The causes and the effects of this phenomenon are not clear. The objective of the study is to evaluate the relationship of AT postoperative values on short and mid-term outcome after cardiac surgery.


METHODS
Between January and June 2005, 405 patients, who underwent cardiac operations at our Institution had AT values available preoperatively and postoperatively. Using Receiver Operating Characteristic curves, a cut-off equal to 63.7% for ICU-arrival AT was chosen in order to divide the entire population in two groups (117 patients with ICU-arrival AT < 63.7%, Low AT group, and 288 patients with ICU-arrival AT > or = 63.7%, High AT group). Objective of the study was to evaluate the predictive role of ICU-arrival AT < 63.7% on in-hospital mortality and morbidity and on 18 months follow-up after cardiac surgery.


RESULTS
ICU-arrival AT was significantly lower than preoperative AT (90.7 +/- 16.3% vs. 71.2 +/- 15.1%, P < 0.0001). Patients in the Low AT group were older, more often female, had a worse Euroscore and required longer CPB duration and cross clamp time. They had significantly higher preoperative and postoperative D-dimer levels. ICU arrival AT < 63.7% was not associated with increased in-hospital mortality but it was an independent risk factor for longer mechanical ventilation, need of inotropic support, excessive bleeding and blood products transfusion. ICU arrival-AT < 63.7% was associated with worse survival during 18 months follow up (92.3% vs. 85.4% in the High AT and Low AT group, respectively, P = 0.05).


CONCLUSIONS
Low AT after cardiac surgery is associated with higher incidences of peri-operative complications and worse survival in the mid-term. Future studies should clarify the pathophysiologic mechanism of this findings and possible therapeutic directions.
Paparella
Domenico
D
Dipartimento di Emergenza e Trapianti di Organo (D.E.T.O.), Division of Cardiac Surgery, University of Bari, Piazza Giulio Cesare 11, Bari, 70100, Italy. dpaparella@cardiochir.uniba.it
Cappabianca
Giangiuseppe
G
Scrascia
Giuseppe
G
Fiore
Giuseppe
G
Paramythiotis
Andreas
A
Di Bari
Nicola
N
Liuzzi
Maria Pia Trisorio
MP
Ibrahim
Mohamed F
MF
Fiore
Tommaso
T
de Luca Tupputi Schinosa
Luigi
L
D000368:Aged; D020152:Antithrombin III Deficiency / Q000453:epidemiology* / Q000209:etiology; D016913:Blood Component Transfusion / Q000706:statistics & numerical data; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000706:statistics & numerical data; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000706:statistics & numerical data; D002423:Cause of Death; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011183:Postoperative Complications / Q000453:epidemiology / Q000401:mortality; D011184:Postoperative Period; D012121:Respiration, Artificial / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D016019:Survival Analysis; D016896:Treatment Outcome