Myocardial injury in major aortic surgery.
OBJECTIVE
The purpose of this study was to examine the effects of major aortic surgery and its associated oxidative stress and injury on the myocardium.


METHODS
Plasma from 27 patients who underwent thoracoabdominal aortic aneurysm (TAAA) repair and 17 patients who underwent infrarenal aortic aneurysm (AAA) repair was collected at incision, aortic crossclamping, and reperfusion and 1, 8, and 24 hours thereafter. Samples were assayed for the myocardial specific protein troponin-T, total antioxidant status, and lipid hydroperoxides.


RESULTS
Ten patients experienced cardiac dysfunction in the first 24 hours after surgery (eight patients in the TAAA group and two patients in the AAA group). Immediately after reperfusion, total antioxidant status levels dropped in all patients with TAAA and with AAA; this was more marked in patients with TAAA, leading to a significant difference between the two groups at this time point and for up to 1 hour thereafter (P <.01). Patients with TAAA showed a sharp rise in lipid hydroperoxide levels immediately after reperfusion, and levels were significantly higher than in patients with AAA (P =.0007). In patients with AAA, no significant change in troponin-T was observed throughout the study period; whereas in patients with TAAA, levels were significantly elevated at 8 and 24 hours after reperfusion (P <.01). Troponin-T levels significantly correlated with total antioxidant status (r = -0.5) and lipid hydroperoxides (r = 0.78) but not with systolic blood pressure.


CONCLUSIONS
Supracoeliac aortic crossclamping is associated with a significant release of the myocardial injury marker troponin-T. This seems to correlate with the severity of oxidative rather than hemodynamic stresses. Ameliorating oxidative injury during TAAA surgery may therefore have a cardioprotective effect.
Hafez
H M
HM
Academic Surgical and Regional Vascular Unit, Division of Surgery and Anaesthetics, Imperial College Medical School at St Mary's Hospital, UK.
Berwanger
C S
CS
McColl
A
A
Richmond
W
W
Wolfe
J H
JH
Mansfield
A O
AO
Stansby
G
G
D018806:APACHE; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000975:Antioxidants / Q000032:analysis; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000601:surgery*; D001794:Blood Pressure / Q000502:physiology; D002315:Cardiopulmonary Bypass; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D016014:Linear Models; D008054:Lipid Peroxides / Q000097:blood; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000209:etiology*; D009206:Myocardium / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology; D013997:Time Factors; D020107:Troponin T / Q000097:blood
D000975:Antioxidants; D008054:Lipid Peroxides; D020107:Troponin T