Use of (all-blood) miniplegia versus crystalloid cardioplegia in an experimental model of acute myocardial ischemia

Comparison of Bretschneider HTK and Blood Cardioplegia (4:1): A Prospective Randomized Study

BACKGROUND

We compared the effect of intermittent blood and histidine-tryptophan-ketoglutarate (HTK) solution of Bretschneider on myocardial histopathology and perioperative outcome.

METHODS

Forty adult cardiac surgery patients were grouped into two (n = 20 for each): (1) Intermittent blood cardioplegia (IBC): had repeated cold 4:1 blood cardioplegia and (2) HTK: had a single dose of cold HTK for cardioprotection. Creatine kinase (CK)-MB, Troponin-I (cTn-I), pH, and lactate were studied in coronary sinus blood before and after aortic cross-clamping (AXC) and systemic blood at postoperative 6th, 24th, and 48th hours. Myocardial biopsy was performed before and after AXC for light microscopy. Vacuolation, inflammation, edema, and glycogen were graded semiquantitatively (from 0 to 3). The myocardial apoptotic index was evaluated via the terminal deoxynucleotidyl transferase dUTP nick end labeling.

RESULTS

There were no differences in perioperative clinical outcomes between the groups. The coronary sinus samples after AXC were more acidotic (7.15 ± 0.14 vs. 7.32 ± 0.07, p = 0.001) and revealed higher CK-MB (21.0 ± 12.81 vs. 12.60 ± 11.80, p = 0.008) in HTK compared with IBC. The HTK had significantly a higher amount of erythrocyte suspension intraoperatively compared with IBC (0.21 ± 0.53 vs. 1.68 ± 0.93 U, p = 0.001). Microscopically, myocardial edema was more pronounced in HTK compared with IBC after AXC (2.25 ± 0.91 vs. 1.50 ± 0.04, p = 0.013). While a significant increase in the apoptotic index was seen after AXC in both groups (p = 0.001), no difference was detected between the groups (p = 0.417).

CONCLUSION

IBC and HTK have a similar clinical outcome and protective effect, except for more pronounced myocardial edema and increased need for intraoperative transfusion with HTK.

Myocardial protection in on-pump coronary artery bypass grafting surgery: analysis of the effectiveness of the use of retrograde Celsior®

BACKGROUND

We analyzed the adequacy of the myocardial protection achieved with a single dose of retrograde crystalloid Celsior®, compared with an accepted standard (microplegia), in on-pump coronary artery bypass grafting surgery (CABG).

METHODS

This was a retrospective comparative clinical study conducted in a single institution that included all the patients operated on who had elective isolated on-pump CABG, from March 2006 to June 2014. We evaluated maximum postoperative troponin T (TnT) as a marker of myocardial damage, adjusted for possible confounders using propensity score matching. We also analyzed markers of recovery of myocardial function, and the safety of the intravenous use of Celsior®.

RESULTS

During the study period, 261 patients were included, divided in two groups: (a) continuous retrograde blood-based microplegia (114 patients); (b) retrograde single-dose crystalloid Celsior® (147 patients). The propensity score adjusted maximum TnT was significantly lower in the Celsior group [average treatment effect = -0.55 ng/dl; 95% confidence interval (CI) -1.10 to -0.1 ng/dl; p = 0.048]. There were no differences in the postoperative use of intra-aortic balloon of counterpulsation or in the requirements of high-dose inotropic medications. In-hospital mortality was equivalent in both study groups ( p = 0.73); surgical re-exploration because of bleeding was equivalent ( p = 0.37). There were no differences in prolonged mechanical ventilation ( p = 0.65) and intensive care unit length of stay ( p = 0.87).

CONCLUSION

An isolated single dose of retrograde Celsior® may be an effective and safe myocardial protection strategy in on-pump CABG.

Perioperative serum troponin I levels are associated with higher risk for atrial fibrillation in patients undergoing coronary artery bypass graft surgery

Atrial fibrillation (AF) remains a frequent complication after coronary artery bypass graft surgery (CABG). We evaluate the association of AF occurrence and serum cardiac troponin I (cTnI) levels in the early postoperative period after CABG. Between April 2009 and January 2010, 95 consecutive patients with sinus rhythm who underwent CABG were evaluated. The patients were divided into two groups according to their postoperative rhythms: sinus rhythm group (SR) and AF group (AF). Demographic, clinical variables, and troponin I were evaluated at the pre- and postoperative times. There were no clinical or demographic differences between the two groups. The postoperative troponin I in the SR group was lower than that in the AF group (0.66 ± 1.62 vs. 2.07 ± 5.01 ng/ml; P = 0.029). Using the receiver operating characteristic curves was found as the best cut-off value to predict AF occurrence at the value of 0.901 ng/ml. Using this value of cTnI, a sensitivity of 60% and a specificity of 87% for AF onset prediction were observed. The cTnI serum levels at the postoperative period after CABG were higher in patients who subsequently developed AF. The cut-off value of 0.901 ng/ml is useful for prediction and preventive therapeutic actions.