Postoperative Troponin Release Research Articles

Celsior® vs. St Thomas® cardioplegia: analysis of myocardial protection and clinical safety in neonates.

To compare the effectiveness and safety of Celsior® crystalloid solution to St Thomas® solution as cardioplegia in pediatric arterial switch surgery. A retrospective study was conducted on 180 patients who underwent arterial switch operation (ASO) between 2005 and 2019. The patients were divided into two groups: the St Thomas group receiving St Thomas solution and the Celsior® group receiving Celsior® solution. The study aimed to assess myocardial protection while evaluating clinical outcomes of patients between groups. Baseline characteristics not different between groups. The postoperative troponin release trends and blood lactate levels were not different between groups. However, the Celsior® group had a significant lower incidence of delayed sternal closure (9.7% vs. 19.5%; p = 0.09) and mechanical circulatory support (ECMO) (4.9% vs. 24.7%; p < 0.001) compared to the St Thomas group. The length of stay in the intensive care unit (ICU) was significantly shorter in the Celsior® group (4.6 ± 3.36 days vs. 8.72 ± 5.08 days, respectively; p < 0.001). There was no significant difference in 30-day mortality between the two groups (2.9% vs. 2.6%; p = 0.147). The study suggests that Celsior® solution is effective and safe for myocardial protection in pediatric arterial switch surgery. It may offer potential benefits such as reduced need for delayed sternal closure and ECMO support, as well as shorter ICU stay. However, the study has limitations including its retrospective design and the use of different cardioplegic solutions during different time periods. Further prospective randomized trials are needed for confirmation. ClinicalTrials.gov, ID: NCT04616222.

Association of High-Sensitivity Cardiac Troponin T With 30-Day and 5-Year Mortality After Cardiac Surgery

BackgroundThe relevance of perioperative myocardial injury (PMI) after cardiac surgery for 30-day mortality and long-term survival remains to be determined. ObjectivesThis study assessed the association of PMI after cardiac surgery, reflected by postoperative troponin release, with 30-day mortality and long-term survival after: 1) coronary artery bypass grafting (CABG); 2) isolated aortic valve replacement (AVR) surgery; and 3) all other cardiac surgeries. MethodsA consecutive cohort of 8,292 patients undergoing cardiac surgery with serial perioperative high-sensitivity cardiac troponin T (hs-cTnT) measurements was retrospectively analyzed. The relationship between postoperative hs-cTnT release and 30-day mortality or 5-year mortality was analyzed after adjustment with EuroSCORE II using a Cox proportional hazards model. hs-cTnT thresholds for 30-day and 5-year mortality were determined for isolated CABG (32.3%), AVR (14%), and other cardiac surgery (53.8%). ResultsHigh postoperative hs-cTnT levels were associated with higher 30-day mortality but not 5-year mortality. In CABG, median peak concentration of postoperative hs-cTnT was 1,044 ng/L, in AVR it was 502 ng/L, and in other cardiac surgery it was 1,110 ng/L. hs-cTnT thresholds defining mortality-associated PMI were as follows: for CABG, 2,385 ng/L (170× the upper reference limit of normal in a seemingly healthy population [URL]); for AVR, 568 ng/L (41× URL); and for other cardiac procedures, 1,873 ng/L (134× URL). hs-cTnT levels above the cutoffs resulted in an HR for 30-day mortality for CABG of 12.56 (P < 0.001), for AVR of 4.44 (P = 0.004), and for other cardiac surgery of 3.97 (P < 0.001). ConclusionsPMI reflected by perioperative hs-cTnT release is associated with the expected 30-day mortality but not 5-year mortality. Postoperative hs-cTnT cutoffs to identify survival-relevant PMI are higher than suggested in current definitions.

Del Nido versus blood cardioplegia in adult cardiac surgery: a meta-analysis.

Initially developed for myocardial protection in immature cardiomyocytes, del Nido cardioplegia has been increasingly used over the past decade in adult patients. Our aim is to analyse the results from randomized controlled trials and observational studies comparing early mortality and postoperative troponin release in patients who underwent cardiac surgery using del Nido solution and blood cardioplegia. A literature search was performed through three online databases between January 2010 and August 2022. Clinical studies providing early mortality and/or postoperative troponin evaluation were included. A random-effects meta-analysis with a generalized linear mixed model, incorporating random study effects, was implemented to compare the two groups. Forty-two articles were included in the final analysis for a total of 11 832 patients, 5926 of whom received del Nido solution and 5906 received blood cardioplegia. del Nido and blood cardioplegia populations had comparable age, gender distribution, history of hypertension and diabetes mellitus. There was no difference in early mortality between the two groups. There was a trend towards lower 24 h [mean difference -0.20; 95% confidence interval (CI) -0.40 to 0.00; I2 = 89%; P = 0.056] and lower peak postoperative troponin levels (mean difference -0.10; 95% CI -0.21 to 0.01; I2 = 0.87; P = 0.087) in the del Nido group. del Nido cardioplegia can be safely used in adult cardiac surgery. The use of del Nido solution was associated with similar results in terms of early mortality and postoperative troponin release when compared with blood cardioplegia myocardial protection.

Effects of Remote Ischemic Preconditioning on Decreasing Troponin Release in Patients Not Taking Sulfonylureas After Cardiac Surgery - A Meta-Analysis.

Remote ischemic preconditioning (RIPC) is a new noninvasive myocardial protection strategy that uses blood pressure cuf inflation to simulate transient non-fatal ischemia to protect the myocardium and reduce ischemia-reperfusion injury. Sulfonylureas may mask the effects of RIPC due to their cardioprotec-tive effect. This meta-analysis aimed to evaluate whether RIPC, in the absence of sulfonylureas, reduces troponin release in patients undergoing cardiac surgery. We conducted a meta-analysis of randomized controlled clinical trials to determine whether RIPC can reduce postoperative troponin release in cardiac surgery patients undergoing cardiopulmonary bypass without treatment with sulfonylureas. The data were normalized to equivalent units prior to the analysis. A random-effects model was used to provide more conservative estimate of the effects in the presence of known or unknown heterogeneity. Six studies with a total of 570 participants were included. The analysis showed that troponin release was lower in the RIPC group than in the control group at six hours (test of standardized mean differences = 0, Z=3.64, P<0.001) and 48 hours (Z=2.72, P=0.007) postoperatively. When the mean of cross-clamping time was > 60 minutes, RIPC reduced troponin release at six hours (Z=2.84, P=0.005), 24 hours (Z=2.64, P=0.008), and 48 hours (Z=2.87, P=0.004) postoperatively. In cardiac surgery patients who are not taking sulfonylureas, RIPC can reduce troponin release at six and 48 hours postoperatively; hence, RIPC may serve significant benefits in certain cardiac surgery patients.

Atrial nitroso-redox balance and refractoriness following on-pump cardiac surgery: a randomized trial of atorvastatin.

AimsSystemic inflammation and increased activity of atrial NOX2-containing NADPH oxidases have been associated with the new onset of atrial fibrillation (AF) after cardiac surgery. In addition to lowering LDL-cholesterol, statins exert rapid anti-inflammatory and antioxidant effects, the clinical significance of which remains controversial.Methods and resultsWe first assessed the impact of cardiac surgery and cardiopulmonary bypass (CPB) on atrial nitroso-redox balance by measuring NO synthase (NOS) and GTP cyclohydrolase-1 (GCH-1) activity, biopterin content, and superoxide production in paired samples of the right atrial appendage obtained before (PRE) and after CPB and reperfusion (POST) in 116 patients. The effect of perioperative treatment with atorvastatin (80 mg once daily) on these parameters, blood biomarkers, and the post-operative atrial effective refractory period (AERP) was then evaluated in a randomized, double-blind, placebo-controlled study in 80 patients undergoing cardiac surgery on CPB. CPB and reperfusion led to a significant increase in atrial superoxide production (74% CI 71–76%, n = 46 paired samples, P < 0.0001) and a reduction in atrial tetrahydrobiopterin (BH4) (34% CI 33–35%, n = 36 paired samples, P < 0.01), and in GCH-1 (56% CI 55–58%, n = 26 paired samples, P < 0.001) and NOS activity (58% CI 52–67%, n = 20 paired samples, P < 0.001). Perioperative atorvastatin treatment prevented the effect of CPB and reperfusion on all parameters but had no significant effect on the postoperative right AERP, troponin release, or NT-proBNP after cardiac surgery.ConclusionPerioperative statin therapy prevents post-reperfusion atrial nitroso-redox imbalance in patients undergoing on-pump cardiac surgery but has no significant impact on postoperative atrial refractoriness, perioperative myocardial injury, or markers of postoperative LV function.Clinical Trial Registration https://clinicaltrials.gov/ct2/show/NCT01780740

Routine use of del Nido cardioplegiacompared with blood cardioplegia in all types of adult cardiac surgery procedures.

Several studies reported the safety and potential benefits of single-dose Del Nido cardioplegia (DNC) in selected adult cardiac surgery (ACS) procedures. However, studies are scarce on routine use of DNC in more complex procedures and patients with a high risk profile. We sought to compare DNC with cold blood cardioplegia (BC) in all types of ACS including complex procedures. Data for 305 consecutive unselected patients who underwent ACS procedures (July/2017 to November/2019) were included. DNC was routinely used whenever is available (n = 231) and if not available, cold BC is used (n = 74). All categories of ACS procedures (primary or redo) were included. Repeated measures analysis was performed to compare baseline, peak, and trough Troponins levels in both groups. Linear regression analysis was used to identify independent predictors of peak Troponins level. The two groups were comparable in baseline characteristics including euro score (ES II), risk profile, and surgical complexity. DNC was associated with lower cardiopulmonary bypass (CPB) and cross-clamp times, cardioplegia volume, and number of cardioplegia doses (p < .001). Importantly, DNC was associated with lower postoperative Troponin level (p = .001), shorter duration of inotropic support (p = .02), and shorter intensive care unit stay (p = .04). On linear regression analysis, DNC was an independent predictor of lower postoperative peak Troponin (t = -3.5, p < .001). Routine use of DNC in all types of ACS procedures compared with BC was associated with significantly shorter CPB and clamp times, significantly lower postoperative troponin release, and shorter duration of inotropic support.

Single-Shot Cold Histidine-Tryptophan-Ketoglutarate Cardioplegia for Long Aortic Cross-Clamping Durations in Neonates

More than 30% of European pediatric cardiac surgery centers use single-dose cold histidine-tryptophan-ketoglutarate cardioplegia (Custodiol; Dr Franz Köhler Chemie GmbH, Bensheim, Germany). In neonates with transposition of the great arteries, arterial switch surgery (ASO) implies aortic division, and it is unknown whether repeated ostial cannulation causes intimal insult and affects long-term results, and therefore, single-dose Custodiol is appealing. The present study investigated the association among myocardial no-flow duration, postoperative troponins, and postoperative outcomes in neonates undergoing ASO with Custodiol cardioplegia. Retrospective analysis of the association among myocardial no-flow duration, postoperative troponin release (concentration magnitude × measurement duration within 48 h), and outcomes using stratification according to coronary anatomy and attending surgeon. Single-institutional, tertiary pediatric cardiac surgery unit of a university hospital. The study comprised 101 neonates undergoing ASO. None. The mean age of patients was 6.1 ± 5.4 days, the cardiopulmonary bypass duration was 108.7 ± 54.1 minutes, the temperature during cross-clamping was 31.1°C ± 1.7°C, the duration of mechanical ventilation was 4 (3-6) days, the length of intensive care unit stay was 7 (5-8) days, delayed sternal closure occurred in 32 (31.7%) patients, and no patients died. The myocardial no-flow duration averaged 62.3 ± 14.6 minutes and was linked with both troponin release (p = 0.04) and low cardiac output syndrome, as assessed by the requirement for delayed sternal closure (p = 0.03), regardless of cardiopulmonary bypass duration and temperature. Eighty-two percent of the patients with myocardial no-flow duration >74 minutes necessitated delayed sternal closure. Single-dose Custodiol may be inadequate for prolonged cross-clamping durations without myocardial perfusion in neonates.

Postoperative troponin release is associated with major adverse cardiovascular events in the first year after noncardiac surgery

IntroductionTroponin elevations after intermediate-to-high risk noncardiac surgery are common and can predict mortality. However, the prognostic value for early and late major adverse cardiovascular events (MACE) is less well investigated. The authors evaluated the relationship between postoperative troponin release and MACE in the first year after noncardiac surgery. MethodsThis observational cohort registry comprised data of patients aged ≥60 years undergoing intermediate-to-high risk noncardiac surgery between July 2012 and 2015, at the Erasmus University Medical Center, Rotterdam, the Netherlands. High-sensitivity troponin T was measured on day 1 to 3 after surgery. Peak troponin values were divided into four categories: <14 ng·L−1, 14–49 ng·L−1, 50–149 ng·L−1 and ≥150 ng·L−1. The primary endpoint MACE was defined as the occurrence of myocardial infarction, angina, revascularization therapy or cerebrovascular accident in the first year after surgery. The incidence of MACE and all-cause mortality was calculated using Kaplan-Meier estimates. Cox regression was used to estimate risks for both endpoints. ResultsIn total, 3085 patients were included for analyses and peak troponin elevation above 14 ng·L−1 was present in 1678 (54.4%) patients. The overall incidence for one-year MACE was 5.8% (3.4%, 6.1%, 10.4% and 40.6% per increasing troponin category) with adjusted HR (95% CI) 1.32 (0.85–2.06), 2.53 (1.42–4.53) and 10.24 (5.91–17.75) for the consecutive increasing categories. One-year mortality occurred in 14.6% and showed a similar stepwise increase with adjusted HR (95% CI) 1.25 (0.98–1.60), 2.39 (1.72–3.32) and 3.79 (2.60–5.54). ConclusionOur dataset demonstrates a graded relationship between postoperative troponin release and occurrence of MACE in the first year after intermediate-to-high risk noncardiac surgery.

Improvement of mitochondrial function in human atrial tissue by remote ischemic conditioning

IntroductionRemote ischemic preconditioning (RIPC), repeated cycles of brief limb ischemia/reperfusion, attenuates postoperative troponin release in patients undergoing surgical coronary revascularization and improves clinical outcome in some, but not all studies. Mitochondria are the end‐effectors of cardioprotection by local ischemic conditioning maneuvers in experimental studies. Here, we now analyzed mitochondrial function in response to RIPC in human atrial tissue.MethodsPatients undergoing elective surgical coronary revascularization under isoflurane anesthesia were randomized to RIPC by 3× 5 min/5 min upper arm blood pressure cuff inflation/deflation or placebo (n=30/30), and their right atrial appendages were harvested prior to ischemic cardioplegic arrest. Cardioprotection was reflected by a 14% decrease with RIPC vs. placebo in the area under the curve of serum troponin I/T concentrations over 72 h after surgery. Mitochondria were isolated from the atrial tissue (n=10/10). Mitochondrial function, i.e. mitochondrial respiration, adenosine triphosphate (ATP) production, reactive oxygen species (ROS) production and calcium retention capacity (CRC) to estimate mitochondrial permeability transition pore (mPTP) opening, was measured at physiological temperature of 37°C. Data are given as mean±SEM.ResultsAssociated with the observed cardioprotection in patients, mitochondrial function was improved by RIPC. Basal respiration was not different between RIPC and placebo. ADP‐stimulated complex I respiration was significantly greater with RIPC than with placebo. Mitochondrial complex IV respiration and maximal oxygen uptake of uncoupled mitochondria were not different between RIPC and placebo, reflecting an equal loading of viable mitochondria (Figure 1A). The mitochondrial ATP production (Figure 1B) was greater whereas mitochondrial ROS production (Figure 1C) was less with RIPC than with placebo. CRC of mitochondria (Figure 1D) was improved with RIPC in comparison to placebo, with and without cyclosporine A.ConclusionIn human myocardium, mitochondria are an intracellular target of protection by RIPC.Support or Funding InformationSupported by: German Research Foundation (SFB 1116 B8)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Prognostic value of postoperative high-sensitivity troponin T in patients with different stages of kidney disease undergoing noncardiac surgery

BackgroundEmerging evidence suggests that postoperative troponin release is a strong and independent predictor of short-term mortality. However, evaluating elevated troponins in patients with chronic kidney disease (CKD) is still controversial and is often disregarded. This study examines morbidity along with short- and long-term mortality risk associated with elevated high-sensitivity troponin T (hsTnT) in patients with different stages CKD undergoing noncardiac surgery. MethodsThis observational cohort comprised 3262 patients aged ≥60 yr who underwent noncardiac surgery. Postoperative hsTnT concentrations were divided into normal [<14 ng l−1 (reference)], low (14–49 ng l−1), moderate (50–149 ng l−1), and high (≥150 ng l−1) groups. A threshold of 50 ng l−1 was used to dichotomize hsTnT. The study endpoints were 30-day and long-term all-cause mortality, and postoperative myocardial infarction. ResultsPostoperative hsTnT was associated with a stepwise increase in 30-day and long-term mortality risk: low hsTnT adjusted hazard ratio (HR) 1.4 [95% confidence interval (CI): 1.1–1.7], moderate hsTnT adjusted HR 3.1 (95% CI: 2.3–4.3), high hsTnT adjusted HR 5.5 (95% CI: 3.6–8.4). Postoperative hsTnT ≥50 ng l−1 was associated with 30-day and long-term mortality risk for each stage of CKD. Elevated troponin concentrations in severe CKD (estimated glomerular filtration rate <30 mL min−1 1.73 m−2), however, did not predict short-term death. ConclusionsElevated postoperative hsTnT is associated with a dose-dependent increase in 30-day and long-term mortality risk in each stage of CKD with an estimated glomerular filtration rate ≥30 ml min−1 1.73 m−2.

MortalitY in caRdIAc surgery (MYRIAD): A randomizeD controlled trial of volatile anesthetics. Rationale and design

ObjectiveThere is initial evidence that the use of volatile anesthetics can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalization following coronary artery bypass graft (CABG) surgery. Nevertheless, small randomized controlled trials have failed to demonstrate a survival advantage. Thus, whether volatile anesthetics improve the postoperative outcome of cardiac surgical patients remains uncertain. An adequately powered randomized controlled trial appears desirable. DesignSingle blinded, international, multicenter randomized controlled trial with 1:1 allocation ratio. SettingTertiary and University hospitals. InterventionsPatients (n=10,600) undergoing coronary artery bypass graft will be randomized to receive either volatile anesthetic as part of the anesthetic plan, or total intravenous anesthesia. Measurements and main resultsThe primary end point of the study will be one-year mortality (any cause). Secondary endpoints will be 30-day mortality; 30-day death or non-fatal myocardial infarction (composite endpoint); cardiac mortality at 30day and at one year; incidence of hospital re-admission during the one year follow-up period and duration of intensive care unit, and hospital stay. The sample size is based on the hypothesis that volatile anesthetics will reduce 1-year unadjusted mortality from 3% to 2%, using a two-sided alpha error of 0.05, and a power of 0.9. ConclusionsThe trial will determine whether the simple intervention of adding a volatile anesthetic, an intervention that can be implemented by all anesthesiologists, can improve one-year survival in patients undergoing coronary artery bypass graft surgery.

Multicentre double-blind randomized controlled trial of perhexiline as a metabolic modulator to augment myocardial protection in patients with left ventricular hypertrophy undergoing cardiac surgery.

Patients undergoing cardiac surgery require adequate myocardial protection. Manipulating myocardial metabolism may improve the extent of myocardial protection. Perhexiline has been shown to be an effective anti-anginal agent due to its metabolic modulation properties by inhibiting the uptake of free fatty acids into the mitochondrion, and thereby promoting a more efficient carbohydrate-driven myocardial metabolism. Metabolic modulation may augment myocardial protection, particularly in patients with left ventricular hypertrophy (LVH) known to have a deranged metabolic state and are at risk of poor postoperative outcomes. This study aimed to evaluate the role of perhexiline as an adjunct in myocardial protection in patients with LVH secondary to aortic stenosis (AS), undergoing an aortic valve replacement (AVR). In a multicentre double-blind randomized controlled trial of patients with AS undergoing AVR ± coronary artery bypass graft surgery, patients were randomized to preoperative oral therapy with either perhexiline or placebo. The primary end point was incidence of inotrope use to improve haemodynamic performance due to a low cardiac output state during the first 6 h of reperfusion, judged by a blinded end points committee. Secondary outcome measures included haemodynamic measurements, electrocardiographic and biochemical markers of new myocardial injury and clinical safety outcome measures. The trial was halted early on the advice of the Data Safety and Monitoring Board. Sixty-two patients were randomized to perhexiline and 65 to placebo. Of these, 112 (54 perhexiline and 48 placebo) patients received the intervention, remained in the trial at the time of the operation and were analysed. Of 110 patients who achieved the primary end point, 30 patients (16 perhexiline and 14 placebo) had inotropes started appropriately; there was no difference in the incidence of inotrope usage OR of 1.65 [confidence interval (CI): 0.67-4.06] P = 0.28. There was no difference in myocardial injury as evidenced by electrocardiogram odds ratio (OR) of 0.36 (CI: 0.07-1.97) P = 0.24 or postoperative troponin release. Gross secondary outcome measures were comparable between the groups. Perhexiline as a metabolic modulator to enhance standard myocardial protection does not provide an additional benefit in haemodynamic performance or attenuate myocardial injury in the hypertrophied heart secondary to AS. The role of perhexiline in cardiac surgery is limited.

Volatile compared with total intravenous anaesthesia in patients undergoing high-risk cardiac surgery: a randomized multicentre study

The effect of anaesthesia on postoperative outcome is unclear. Cardioprotective properties of volatile anaesthetics have been demonstrated experimentally and in haemodynamically stable patients undergoing coronary artery bypass grafting. Their effects in patients undergoing high-risk cardiac surgery have not been reported. We performed a multicentre, randomized, parallel group, controlled study among patients undergoing high-risk cardiac surgery (combined valvular and coronary surgery) in 2008-2011. One hundred subjects assigned to the treatment group received sevoflurane for anaesthesia maintenance, while 100 subjects assigned to the control group received propofol-based total i.v. anaesthesia. The primary outcome was a composite of death, prolonged intensive care unit (ICU) stay, or both. Thirty day and 1 yr follow-up, focused on mortality, was performed. All 200 subjects completed the follow-up and were included in efficacy analyses, conducted according to the intention-to-treat principle. Death, prolonged ICU stay, or both occurred in 36 out of 100 subjects (36%) in the propofol group and in 41 out of 100 subjects (41%) in the sevoflurane group; relative risk 1.14, 95% confidence interval 0.8-1.62; P=0.5. No difference was identified in postoperative cardiac troponin release [1.1 (0.7-2) compared with 1.2 (0.6-2.4) ng ml(-1), P=0.6], 1 yr all-cause mortality [11/100 (11%) compared with 11/100 (11%), P=0.9], re-hospitalizations [20/89 (22.5%) compared with 11/89 (12.4%), P=0.075], and adverse cardiac events [10/89 (11.2%) compared with 9/89 (10.1%), P=0.8]. There was no observed beneficial effect of sevoflurane on the composite endpoint of prolonged ICU stay, mortality, or both in patients undergoing high-risk cardiac surgery. ClinicalTrials.gov: identifier NCT00821262. Eudra CT (2008-001752-43).

Myocardial protection with prophylactic oral metoprolol during coronary artery bypass grafting surgery: evaluation by troponin I

IntroductionBiochemical markers of myocardial injury are frequently altered after cardiac surgery. So far there is no evidence whether oral beta-blockers may reduce myocardial injury after coronary artery bypass grafting. ObjectiveTo determine if oral administration of prophylactic metoprolol reduces the release of cardiac troponin I in isolated coronary artery bypass grafting, not complicated by new Q waves. MethodsA prospective randomized study, including 68 patients, divided in 2 groups: Group A (n=33, control) and B (n=35, beta-blockers). In group B, metoprolol tartrate was administered 200 mg/day. The myocardial injury was assessed by troponin I with 1 hour and 12 hours after coronary artery bypass grafting. ResultsNo significant difference between groups regarding pre-surgical, surgical, complication in intensive care (15% versus 14%, P=0.92) and the total number of hospital events (21% versus 14%, P=0.45) was observed. The median value of troponin I with 12 hours in the study population was 3.3 ng/ml and was lower in group B than in group A (2.5 ng/ml versus 3.7 ng/ml, P<0,05). In the multivariate analysis, the variables that have shown to be independent predictors of troponin I release after 12 hours were: no beta-blockers administration and number of vessels treated. ConclusionThe results of this study in uncomplicated coronary artery bypass grafting, comparing the postoperative release of troponin I at 12 hours between the control group and who used oral prophylactic metoprolol for at least 72 hours, allow to conclude that there was less myocardial injury in the betablocker group, giving some degree of myocardial protection.

Adenosine instead of supranormal potassium in cardioplegia: It is safe, efficient, and reduces the incidence of postoperative atrial fibrillation. A randomized clinical trial

We aimed to evaluate the efficacy and safety of a cold crystalloid cardioplegic solution with adenosine (1.2 mmol/L) instead of supranormal potassium. Sixty low-risk patients scheduled for elective coronary artery bypass grafting (CABG) were randomized to receive standard cold crystalloid hyperkalemic cardioplegia (hyperkalemic group) or normokalemic cardioplegia in which supranormal potassium was replaced with 1.2 mmol/L adenosine (adenosine group). End points were postoperative release of troponin T and creatine kinase MB, hemodynamics measured by PiCCO arterial thermodilution catheters, perioperative release of markers of endothelial activation and injury, and clinical course. The adenosine group had a significantly shorter time to arrest than did the hyperkalemic group (mean ± standard deviation, 11 ± 5 vs 44 ± 18 seconds; P < .001). Three hearts in the adenosine group were probably not adequately drained and received additional hyperkalemic cardioplegia to maintain satisfactory cardioplegic arrest. There were no differences between groups with respect to perioperative release of markers of endothelial activation or injury and no differences between groups in postoperative release of troponin T or creatine kinase MB. Postoperative hemodynamics including cardiac index were similar between groups. The incidence of postoperative atrial fibrillation was significantly lower in the adenosine group than in the hyperkalemic group (4 vs 15; P = .01). Adenosine instead of hyperkalemia in cold crystalloid cardioplegia is safe, gives more rapid cardiac arrest, and affords similar cardioprotection and maintenance of hemodynamic parameters, together with a marked reduction in the incidence of postoperative atrial fibrillation.

Red Blood Cell Transfusion Is Associated With Troponin Release After Elective Off-Pump Coronary Artery Bypass Surgery

Increased troponin levels after coronary artery bypass surgery are associated with increased risk of early and late mortality. We hypothesized that perioperative blood transfusion is associated with increased postoperative troponin release. Complete data on perioperative blood transfusion and troponin I were available for 140 patients who underwent isolated, elective off-pump coronary artery bypass graft surgery. Linear regression analysis showed that red blood cell (RBC) transfusion (p=0.007) was an independent predictor of troponin I levels on the first postoperative day. The RBC transfusion was associated with a high risk of type V myocardial infarction as indicated by troponin I levels greater than 6.6 μg/L on the first postoperative day (9 of 58 patients [15.5%] versus 1 of 82 patients [1.2%], p=0.002; adjusted analysis odds ratio 14.878, 95% confidence interval: 1.829 to 121.033). This finding did not change when hemoglobin and hematocrit nadirs were included in the analysis. Repeated-measure test showed that any blood product transfusion (p=0.040), any blood product transfusion on the operation day (p=0.025), any RBC transfusion (p=0.014), and RBC transfusion on the operation day (p=0.026) were associated with increased postoperative troponin I release. These findings persisted even after adjusting for hemoglobin and hematocrit nadirs. Red blood cell transfusion is associated with increased troponin I release after elective off-pump coronary artery bypass graft surgery independently of hemoglobin and hematocrit nadirs. These findings suggest that prevention of major bleeding requiring blood transfusion may be cardioprotective during coronary surgery. Further studies are needed to verify whether troponin release is affected simply by RBC transfusion or by unstable hemodynamic conditions in presence of mild and severe anemia.

Timing of Preoperative Aspirin Discontinuation and Outcome After Elective Coronary Artery Bypass Graft Surgery

Whether aspirin should be discontinued before coronary artery bypass grafting is controversial. The potential benefits and harms associated with late use of aspirin (no discontinuation or discontinuation <3 days before surgery) were investigated in this retrospective, multicenter study. Retrospective, multicenter study. Two university hospitals and one central hospital. A consecutive series of 859 patients who underwent elective coronary artery bypass grafting from January 2008 through December 2010. Aspirin (100 mg/day) was used <3 days before surgery in 240 patients and was discontinued >3 days before surgery in 619 patients. In the overall series, similar in-hospital mortality, amount of postoperative blood loss, rate of re-exploration for excessive bleeding, and use of blood products were observed in the study groups. However, aspirin discontinuation >3 days before surgery tended to be associated with a higher postoperative stroke rate (1.9% v 0.4%, p = 0.13). Such a trend was observed after off-pump (1.9% v 0%, p = 0.58) and on-pump (2.0% v 0.6%, p = 0.46) surgery. Among 153 pairs matched by the propensity score, patients with aspirin discontinued >3 days before surgery had a significantly higher rate of postoperative stroke (5.9% v 0.7%, p = 0.02) and tended to have a higher risk of the composite adverse outcome endpoint (19.6% v 12.4%, p = 0.09). The postoperative release of troponin I was similar in the study groups. Late or no discontinuation of low-dose aspirin before coronary artery bypass grafting may decrease the risk of postoperative stroke without increased postoperative bleeding and need for blood transfusion. These findings and the risk of cardiovascular events possibly occurring at the time of its discontinuation suggest that the use of aspirin until the day of elective coronary surgery may be beneficial.

Sevoflurane vs. propofol in patients with coronary disease undergoing mitral surgery: a randomised study

Myocardial ischemic damage is reduced by volatile anaesthetics in patients undergoing low-risk coronary artery bypass graft surgery; few and discordant results exist in other settings. We therefore performed a randomised controlled trial (sevoflurane vs. propofol) to compare cardiac troponin release in patients with coronary disease undergoing mitral surgery. Patients with coronary artery disease undergoing mitral surgery were randomly allocated to receive either sevoflurane (50 patients) or propofol (50 patients) as main hypnotic. The primary endpoint of the study was peak post-operative cardiac troponin release defined as the maximum value among the post-operative values measured at intensive care unit arrival, 4 h later, on the first and second post-operative day. There was no significant difference in post-operative peak troponin release, the median (25th-75th percentiles) values being 14.9 (10.1-22.1) ng/ml and 14.5 (8.8-17.6) ng/ml in the sevoflurane and propofol groups, respectively (P = 0.4). Fentanyl administration was different between the two groups: 1347 ± 447 μg in patients receiving sevoflurane and 1670 ± 469 μg in those receiving propofol, P = 0.002. The 1-year follow-up identified two patients who died in the propofol group (one myocardial infarction and one low cardiac output syndrome) and one in the sevoflurane group (myocardial infarction). In this study, patients with coronary artery disease undergoing mitral surgery did not benefit from the cardioprotective properties of halogenated anaesthetics. Sevoflurane anaesthesia was not associated to lower cardiac troponin release when compared with propofol anaesthesia.

327 The clinical significance of troponin release after coronary artery bypass surgery: does the new universal definition of post-operative myocardial infarction fit well with the long-term prognosis?

In the new (2007) universal definition for myocardial infarction (MI), the type-5 corresponded to MI after coronary revascularization, with cardiac enzymes release >5x normal values (N) required after coronary artery bypass graft (CABG) surgery. However, data on long-term prognosis of patients with post-operative troponin release are scarce. We followed up 826 consecutive patients operated for CABG between 1998 and 2002 in our institution. Post-operative troponin Ic (Tr-Ic) release has been systematically monitored. The primary outcome was total mortality. The secondary outcome was composite and combined: death, acute coronary syndrome, stroke, coronary or peripheral revascularization. Among the 693 men and 133 women (age 66.1 ± 9.3 yrs), post-operative Tr-Ic peak >5xN, >10xN and >20xN were at 54.8%, 29.6% and 15.6%, respectively. During the follow-up period (6.5 ± 2.7 yrs), 146 (17.6%) deceased, and 302 (36.6%) met the composite outcome. Only the survival curves of those with Tr-Ic peak >10xN were significantly poorer than those without type-5 MI (Figure). Adjusted for age, sex, use of beta-blockers and statins, CVD risk factors, NYHA stage, LVEF <40%, number of bypasses, on/off-pump surgery, atrial fibrillation, peripheral artery or chronic kidney disease, only Tr-Ic >20xN was associated with mortality, and Tr-Ic >10xN was predictive for the composite outcome (table). This series with the longest follow-up ever published confirms the prognostic value of troponin release after CABG. However, the current type-5 MI definition after CABG is not specific enough to stratify the long-term post-operative prognosis. Higher thresholds are mandatory. Table-Post-CABG troponin and long-term prognosis (abstract 327). Mortality Composite endpoint Tr-Ic peak HR (95%CI) p HR (95%CI) p < 5xN ref ref 5 to <10 xN 1.02 (0.65–1.61) ns 1.14 (0.84–1.55) ns 10 to <20 xN 1.33 (0.78–2.26) ns 1.45 (1.02–2.07) 0.04 20 xN 1.81 (1.14–2.88) 0.01 1.38 (1.00–1.94) 0.05 Figure - Survival according to post-CABG troponin

The efficacy and safety of clopidogrel in vascular surgery patients with immediate postoperative asymptomatic troponin T release for the prevention of late cardiac events: Rationale and design of the Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echo-VII (DECREASE-VII) trial

Major vascular surgery patients are at high risk for developing asymptomatic perioperative myocardial ischemia reflected by a postoperative troponin release without the presence of chest pain or electrocardiographic abnormalities. Long-term prognosis is severely compromised and characterized by an increased risk of long-term mortality and cardiovascular events. Current guidelines on perioperative care recommend single antiplatelet therapy with aspirin as prophylaxis for cardiovascular events. However, as perioperative surgical stress results in a prolonged hypercoagulable state, the postoperative addition of clopidogrel to aspirin within 7 days after perioperative asymptomatic cardiac ischemia could provide improved effective prevention for cardiovascular events. DECREASE-VII is a phase III, randomized, double-blind, placebo-controlled, multicenter clinical trial designed to evaluate the efficacy and safety of early postoperative dual antiplatelet therapy (aspirin and clopidogrel) for the prevention of cardiovascular events after major vascular surgery. Eligible patients undergoing a major vascular surgery (abdominal aorta or lower extremity vascular surgery) who developed perioperative asymptomatic troponin release are randomized 1:1 to clopidogrel or placebo (300-mg loading dose, followed by 75 mg daily) in addition to standard medical treatment with aspirin. The primary efficacy end point is the composite of cardiovascular death, stroke, or severe ischemia of the coronary or peripheral arterial circulation leading to an intervention. The evaluation of long-term safety includes bleeding defined by TIMI criteria. Recruitment began early 2010. The trial will continue until 750 patients are included and followed for at least 12 months. DECREASE-VII is evaluating whether early postoperative dual antiplatelet therapy for patients developing asymptomatic cardiac ischemia after vascular surgery reduces cardiovascular events with a favorable safety profile.