Cardiac troponin T and troponin I release during coronary artery surgery using cold crystalloid and cold blood cardioplegia.
OBJECTIVE
To evaluate and compare myocardial protection using cold crystalloid and blood cardioplegia by measuring release of cardiac Troponin T and Troponin I during coronary artery surgery.


METHODS
Forty two patients undergoing myocardial revascularization were prospectively randomised into two groups in whom myocardial protection was achieved with either antegrade cold (4 degrees C) crystalloid (CCP) (n = 21) St. Thomas' I cardioplegic solution. Serial venous blood samples were collected for measurement of cardiac Troponin T and Troponin I, prior to induction of anesthesia and at 4, 12, 24 and 48 h after removal of the aortic cross clamp.


RESULTS
There were no hospital deaths in the two groups and one patient in each group suffered a perioperative myocardial infarction. Rising levels of Troponin T and Troponin I were found in all patients. Serum concentrations increased as early as 4 h after removal of the aortic cross clamp, and reached a peak at 12 h postoperatively in both groups. These levels subsequently declined, but remained higher than preoperative values at 48 h. There were no differences between the two groups with respect to serum Troponin T and I release at 4, 12, 24 and 48 h, area under the respective curves, and peak Troponin T and I release. Serum Troponin levels were significantly higher in patients with unstable angina and in two patients who suffered a perioperative myocardial infarction.


CONCLUSIONS
Serum release of cardiac Troponin T and Troponin I is significantly raised in low risk patients undergoing myocardial revascularization. This release is similar when either cold crystalloid or cold blood cardioplegia are used. This may imply that both methods offer identical protection to the myocardium in a low risk group of patients.
Caputo
M
M
Bristol Heart Institute, Bristol Royal Infirmary, UK.
Dihmis
W
W
Birdi
I
I
Reeves
B
B
Suleiman
M S
MS
Angelini
G D
GD
Bryan
A J
AJ
D000368:Aged; D000787:Angina Pectoris / Q000097:blood / Q000601:surgery*; D000789:Angina, Unstable / Q000097:blood / Q000601:surgery; D015415:Biomarkers / Q000097:blood; D003080:Cold Temperature; D001026:Coronary Artery Bypass / Q000379:methods*; D000077324:Crystalloid Solutions; D005260:Female; D006324:Heart Arrest, Induced / Q000379:methods*; D006801:Humans; D007552:Isotonic Solutions; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D015425:Myocardial Reperfusion; D010952:Plasma Substitutes / Q000008:administration & dosage*; D011446:Prospective Studies; D012044:Regression Analysis; D015532:Rehydration Solutions / Q000008:administration & dosage*; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014336:Troponin / Q000097:blood*; D019210:Troponin I / Q000097:blood*; D020107:Troponin T
D015415:Biomarkers; D000077324:Crystalloid Solutions; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D015532:Rehydration Solutions; D014336:Troponin; D019210:Troponin I; D020107:Troponin T