Perioperative Myocardial Injury Research Articles

Correlation of angiotensin converting enzyme gene polymorphism with perioperative myocardial protection under extracorporeal circulation

ObjectiveTo observe the expression of angiotensin converting enzyme (ACE), angiotensin II (Ang II), cardiac troponin (cTn I), creatine kinase isozymes (CK-MB) and muscle red protein(Myo) after cardiopulmonary bypass (CPB), and to investigate the association of polymorphisms in angiotensin converting enzyme genes and myocardial injury. MethodsSixty-three patients suffered from rheumatic mitral stenosis and scheduled for mitral valve replacement with CPB, were randomly divided into three groups according polymorphisms in angiotensin converting enzyme genes: type II, type ID, type DD (each=21). Blood samples were withdrawn from artery before operation (T1), at the beginning of CPB (T2), 30 min after CPB (T3), (T4) at the end of CPB (T5), 2 h after CPB (T6), 6 h after CPB (T7) to measure the expression of ACE, Ang II, cTn I, CK-MB, Myo. ResultsThe level of ACE during and after CPB were significantly higher than those before CPB (P<0.05). As extension of CPB time, the expression of ACE was increased. The level of cTn I, CK-MB, Myo after CPB were significantly higher than those before CPB(P<0.05). The level of cTn I, CK-MB and Myo were highest at T7, T6 and T5 and T7, respectively. The level of ACE, Ang II cTn I in patients with DD genotype was significantly higher than the ID and II genotype (P< 0.05). Besides, the level of ACE, Ang II in patients with ID genotype was significantly higher than the II (P< 0.05). ConclusionsThere is certain correlation between CPB perioperative midterm ACE and cTn I, Myo, CK-MB. ACE DD genotype is a susceptibility gene of the CPB perioperative myocardial injury.

Abstract 9965: Prediction and Diagnosis of Perioperative Myocardial Infarction with High-sensitivity troponin T

Introduction The role of high-sensitivity troponin assays in the prediction and diagnosis of perioperative myocardial infarction is unknown. Methods This is an ancillary study of the Vitamins in Nitrous Oxide (VINO) Trial where 625 patients with or at risk for coronary artery disease undergoing major noncardiac surgery were studied..Plasma hsTnT (Roche) and standard troponin I (Siemens) were measured serially and 12-lead ECGs were obtained. Results At baseline 75% of patients (455/606) had a measurable preoperative hsTNT and 25% had a hsTnT &lt;3 pg/mL. The median hsTnT was 7.4 pg/mL (IQR 2.3 - 15.2). Postoperatively, 409/568 patients (72%) had an increase in hsTnT (median 2.9 pg/mL; IQR 0 - 7.4) and 159/569 (28%) had no change. The median peak hsTnT was 12.2 pg/mL (IQR 6.1 - 23.0). Peak and delta hsTnT and troponin I measurements were tightly correlated (r= 0.99 and 0.99, respectively). Eighty-two patients (13%) had a clinically relevant postoperative TnI elevation &gt;0.07 ng/mL and 30/605 (5%) had a myocardial infarction. Using the median preoperative hsTnT concentration of 7.4 pg/mL, patients above this level had a nearly 3-fold risk to develop a clinically significant postoperative troponin elevation (odds ratio 2.80, 95% CI: 1.69 - 4.63, p&lt; 0.001) and to develop postoperative myocardial infarction (odds ratio 2.94, 95% CI 1.29 - 6.71, p= 0.007). At 7.4 pg/mL, the sensitivity and specificity for postoperative troponin elevation were 71% and 54% and for postoperative myocardial infarction 73% and 52% (Figure 1). Conclusions: Preoperative hsTNT concentrations can be detected in most adult patients with or at risk for coronary artery disease before surgery and may be useful in preoperative risk-stratification for postoperative myocardial infarction. Postoperative increase in hsTnT (delta hsTnT) is common among patients with cardiovascular risk factors and may be useful as objective quantification of perioperative myocardial injury.

Journal-related Activities and Other Special Activities at the 2012 American Society of Anesthesiologists Annual Meeting

Journal-related Activities and Other Special Activities at the 2012 American Society of Anesthesiologists Annual Meeting

Cardioprotection during cardiac surgery

Coronary heart disease (CHD) is the leading cause of morbidity and mortality worldwide. For a large number of patients with CHD, coronary artery bypass graft (CABG) surgery remains the preferred strategy for coronary revascularization. Over the last 10 years, the number of high-risk patients undergoing CABG surgery has increased significantly, resulting in worse clinical outcomes in this patient group. This appears to be related to the ageing population, increased co-morbidities (such as diabetes, obesity, hypertension, stroke), concomitant valve disease, and advances in percutaneous coronary intervention which have resulted in patients with more complex coronary artery disease undergoing surgery. These high-risk patients are more susceptible to peri-operative myocardial injury and infarction (PMI), a major cause of which is acute global ischaemia/reperfusion injury arising from inadequate myocardial protection during CABG surgery. Therefore, novel therapeutic strategies are required to protect the heart in this high-risk patient group. In this article, we review the aetiology of PMI during CABG surgery, its diagnosis and clinical significance, and the endogenous and pharmacological therapeutic strategies available for preventing it. By improving cardioprotection during CABG surgery, we may be able to reduce PMI, preserve left ventricular systolic function, and reduce morbidity and mortality in these high-risk patients with CHD.

Risk factors for post-transplant low output syndrome

Due to a serious heart donor shortage, the criteria for acceptance for transplantation have been expanded. This study assesses donor-related factors associated with postoperative low output syndrome (LOS) and long-term survival of recipients. From 1999 to February 2011, 36 heart transplantations were performed at our institute, of which 28 donor hearts (78%) were considered to be marginal due to high inotropic requirement (n = 11), recent episode of cardiac arrest (n = 11), female to male transplantation (n = 11), reduced left ventricular contraction (n = 6), old age (n = 6), small donor heart (n = 5), donor-recipient size mismatch (n = 2), ventricular hypertrophy (n = 2) or prolonged ischaemic time (n = 1). St Thomas solution (n = 6) and Celsior (n = 30) were used for preservation. Ischaemic damage in post-transplant cardiac patients was graded by perioperative ischaemic myocardial injury (PIMI) score (scores 0-3). The donor age was 39 ± 11 years old, which was not significantly different to that of the recipients. 50% of the donors were female. Thirty-three donors (92%) required catecholamine at an average of 8.0 ± 5.2 µg/hg/min and echocardiogram findings showed that left ventricular ejection fraction was 65 ± 10%. All recipients survived during the perioperative period (one patient died from sepsis at 4 years after transplantation) for a 10-year survival rate of 95%. Severe primary graft dysfunction was observed in two patients who required intra-aortic balloon pumping or veno-arterial extra-corporeal membrane oxygenation, and five other patients showed postoperative LOS (cardiac index < 2.2 l/min/m(2)). Left ventricular diastolic diameter smaller than 36 mm (P = 0.0002), high inotropic requirement (P = 0.0089) and left ventricular ejection fraction less than 55% (P = 0.0383) were related to post-transplant LOS. All patients recovered cardiac function and were discharged from the intensive care unit after an average of 6 days. Although preservation with Celsior was not related to LOS, it had relationships with lower CKMB level (P = 0.0013) and lower PIMI score (P = 0.0054). Cautious donor selection is essential when the donor heart has a small ventricular diameter or requires a high level of inotropic support. However, long-term survival in recipients with marginal donor hearts can be anticipated with adequate treatment.

Polymorphism in the protease‐activated receptor‐4 gene region associates with platelet activation and perioperative myocardial injury

Protease-activated receptors (PAR)-1 and -4 are the principal receptors for thrombin-mediated platelet activation. Functional genetic variation has been described in the human PAR1 gene, but not in the PAR4 gene (F2RL3). We sought to identify variants in and around F2RL3 and to determine their association with perioperative myocardial injury (PMI) after coronary artery bypass graft surgery. We further explored possible mechanisms for F2RL3 single nucleotide polymorphism (SNP) associations with PMI including altered receptor expression and platelet activation. Twenty-three SNPs in the F2RL3 gene region were genotyped in two phases in 934 Caucasian subjects. Platelets from 43 subjects (23 major allele, 20 risk allele) homozygous for rs773857 (SNP with the strongest association with PMI) underwent flow cytometry to assess PAR4 receptor number and response to activation by a specific PAR4 activating peptide (AYPGKF) measured by von Willebrand factor (vWf) binding and P-selectin release and PAC-1 binding. We identified a novel association of SNP rs773857 with PMI (OR = 2.4, P = 0.004). rs773857 risk allele homozygotes have significantly increased platelet counts and platelets showed a significant increase in P-selectin release after activation (P = 0.004). We conclude that rs773857 risk allele homozygotes are associated with risk for increased platelet count and hyperactivity.

Effect of remote ischemic preconditioning on clinical outcomes in patients undergoing coronary artery bypass graft surgery (ERICCA): rationale and study design of a multi-centre randomized double-blinded controlled clinical trial

Novel cardioprotective strategies are required to improve clinical outcomes in high risk patients undergoing coronary artery bypass graft (CABG)±valve surgery. Remote ischemic preconditioning (RIC), in which brief episodes of non-lethal ischemia and reperfusion are applied to the arm or leg, has been demonstrated to reduce perioperative myocardial injury following CABG±valve surgery. Whether RIC can improve clinical outcomes in this setting is unknown and is investigated in the effect of remote ischemic preconditioning on clinical outcomes (ERICCA) trial in patients undergoing CABG surgery. (ClinicalTrials.gov Identifier: NCT01247545). The ERICCA trial is a multicentre randomized double-blinded controlled clinical trial which will recruit 1,610 high-risk patients (Additive Euroscore ≥5) undergoing CABG±valve surgery using blood cardioplegia via 27 tertiary centres over 2years. The primary combined endpoint will be cardiovascular death, non-fatal myocardial infarction, coronary revascularization and stroke at 1year. Secondary endpoints will include peri-operative myocardial and acute kidney injury, intensive care unit and hospital stay, inotrope score, left ventricular ejection fraction, changes of quality of life and exercise tolerance. Patients will be randomized to receive after induction of anesthesia either RIC (4 cycles of 5min inflation to 200mmHg and 5min deflation of a blood pressure cuff placed on the upper arm) or sham RIC (4 cycles of simulated inflations and deflations of the blood pressure cuff). The findings from the ERICCA trial have the potential to demonstrate that RIC, a simple, non-invasive and virtually cost-free intervention, can improve clinical outcomes in higher-risk patients undergoing CABG±valve surgery.

Evaluation of Myocardial Cell Injuries and Oxidative Stress Mechanisms in Neonates and Infants after Surgical Correction of Congenital Heart Disease

Background and aims: Despite advances in pediatric cardiac surgery, perioperative myocardial injury can be the major determinant of postoperative dysfunction after cardiac surgery. The objective was to investigate the pathology-related differences in 29 infants with congenital heart disease that led to death.

Perioperative Myocardial Injury and Hemostasis in Patients Undergoing Endovascular Aneurysm Repair for Asymptomatic Infrarenal Abdominal Aortic Aneurysm

(1) To report the incidence of myocardial injury in patients undergoing endovascular aortic aneurysm repair (EVAR) through the routine measurement of perioperative cardiac troponin-T (cTnT) and (2) to investigate and correlate changes in perioperative cTnT levels with any concomitant hemostatic derangement. Prospective study of 30 patients undergoing elective EVAR for infrarenal abdominal aortic aneurysm. Cardiac TnT was assayed at 24 hours postoperatively. Plasma thrombin antithrombin III complex (TAT), plasminogen activator inhibitor 1 (PAI-1), tissue plasminogen activator (t-PA) activity, and soluble P-selectin (sP-selectin) were assayed preoperatively and at 24 hours postoperatively. Five (17%) patients demonstrated elevated cTnT levels at 24 hours; 3 patients had no clinical evidence of myocardial injury. There was a positive correlation between cTnT and TAT levels at 24 hours post-EVAR (r = .38, P = .039, Kendall-tau B = 0.26). Endovascular aortic aneurysm repair is associated with a significant risk of perioperative myocardial injury that is underdetected clinically and associated with a procoagulopathic state.

Failure to recapture cardioprotection with high-dose atorvastatin in coronary artery bypass surgery: a randomised controlled trial

The acute administration of atorvastatin has been reported to reduce myocardial infarct size in animal studies. However, this cardioprotective effect is lost with the chronic administration of atorvastatin, although it can be recaptured by administering an acute high-dose of atorvastatin. We hypothesised that pre-treatment with high-dose atorvastatin, on a background of chronic standard 'statin' therapy, would reduce myocardial injury in patients undergoing elective coronary artery bypass graft (CABG) surgery. One hundred and one consenting patients undergoing elective CABG surgery at a single tertiary cardiac centre were recruited into two randomised controlled, single-blinded clinical studies. Study 1: 45 patients were randomised to receive either 160mg of atorvastatin 2h preoperatively and 24h following surgery or their standard statin therapy. Study 2: 56 patients were randomised to receive either 160mg of atorvastatin 12h preoperatively and 24h following surgery or their standard statin therapy. Blood samples for troponin T and creatine kinase were taken prior to surgery and then at 6, 12, 24, 48 and 72h post-surgery. Cardiac enzyme levels at each time point and the total area-under curve (AUC) were calculated. The group characteristics and surgical methods were well matched. High-dose atorvastatin was not associated with any significant side effects. There was no significant difference in serum troponin T or creatine kinase in either study at each time point or over 72h. Study 1: AUC, troponin T: atorvastatin 29.6±34.8μg/L versus control 25.0±22.0μg/L:P>0.05. Creatine kinase: atorvastatin 33,544±20,063IU/L versus control 30,620±10,776IU/L:P>0.05. Study 2: AUC, troponin T: atorvastatin 21.8±14.3μg/L versus control 20.9±8.7μg/L:P>0.05. Creatine kinase: atorvastatin 36,262±28,821IU/L versus control 33,448±14,984:P>0.05. There were no differences in postoperative outcomes. We report that the administration of high-dose atorvastatin to low risk patients undergoing elective CABG surgery, who are already on standard dose 'statin' therapy is safe, but does not further reduce perioperative myocardial injury.

Toll-like Receptor Signaling during Myocardial Ischemia

Acute myocardial infarction and myocardial ischemia are leading causes of short- and long-term morbidity and mortality in the perioperative period. In part, this relates to the fact that treatment options for a myocardial infarction in surgical patients are extremely limited. For example, anti-coagulation or treatment with highly effective inhibitors of platelet aggregation may not be an option due to the risk for bleeding from the operative site. Therefore, it is not surprising that the search for new pharmacologic approaches to treat myocardial ischemia or to render the myocardium more resistant to limited oxygen availability is an area of intense investigation for perioperative scientists.1-4 In fact, the introduction of intraoperative beta-blockers for cardio-protection from ischemia was one of the most significant alterations in anesthesia practice during the past fifteen years. In line with the search for novel therapeutic approaches to render the myocardium more resistant to ischemia, a very exciting research study by Wang et al. from the research laboratory of Dr. Wei Chao from the Anesthesia Center for Critical Care Research of the Massachusetts General Hospital in Boston provides new insight into signaling pathways involving toll-like receptor (TLR)-elicited cardio-protection from ischemia.1

Increased preoperative C-reactive protein contributes to perioperative myocardial injury

Objectives: C-reactive protein (CRP) is known to be associated with an increased cardiovascular risk. In order to find out if an increased preoperative CRP contributes to perioperative myocardial injury in patients undergoing coronary artery bypass grafting (CABG) we investigated the correlation between CRP and parameters of myocardial injury.

Effect of creatine phosphate on perioperative myocardial injury caused by living donor fiver transplantation in adult patients

Objective To investigate the effect of creatine phosphate on perioperative myocardial injury caused by living donor liver transplantation(LDLT)in adult patients.Methods Forty ASA Ⅱ -Ⅳ patients(liver function Child-Pugh grade B or C)aged 45-62 yr weighing 47-91 kg undergoing LDLT were randomly divided into 2 groups(n = 20 each): control group(group C)and creatine phosphate group(group CP).In group CP,creatine phosphate 30 mg/kg was injected intravenously at skin incision followed by creatine phosphate infusion at 4 mg· kg- 1 · h- 1 until the end of surgery.In group C,equal volume of normal saline was infused instead of creatine phosphate.HR,MAP,CVP,PCWP,CO and SvO2 were recorded immediately before skin incision,at 5 and 30 min of anhepatic phase,at 5 and 30 min of neohepatic phase and at the end of operation.Blood samples were taken from central vein immediately before skin incision(baseline,T0),at 30 min of anhepatic phase(T1),at 30min of neohepatic phase(T2),at the end of operation(T3)and at 4 and 24 h after operation(T4,5)for determination of serum cardiac troponin I(cTnI)and creatine kinase MB(CK-MB)concentrations and lactate dehydrogenase(LDH)activity.Postoperative adverse events were recorded.Results The serum cTnI and CK-MB concentrations and LDH activity were significantly increased at T2-5 as compared with the baseline value at T0 in both groups(P ＜0.05 or 0.01).MAP and CO were significantly higher from 5 min of neohepatic phase to the end of operation,the serum cTnI and CK-MB concentrations and LDH activity were significantly lower at T2-5,and the incidence of ventricular arrhythmia was significantly lower in group CP than in group C(P ＜ 0.05 or 0.01).Conclusion Creatine phosphate can attenuate perioperative myocardial injury caused by LDLT in adult patients. Key words: Phosphocreatine; Liver transplantation; Myocardial reperfusion injury

The protective effect of Dexmedetomidine on perioperative myocardial injury in elderly hypertension patients

Objective To determine the effect of dexmedetomidine in elderly.hypertension patients undergoing hip replacement surgery.Methods Thirty patients with hypertension of Ⅱ degree aged ＞ 65yr undergoing hip replacement surgery were randomly divided into dexmedetomidine group(D) and control group(C) with 15 cases each.Anesthesia induction and maintenance were same in two groups.In group D,dexmedetomidine Was administered intravenously at 0.7 μg/(kg·h)after a bolus infusion at 1μg/(kg·h)for 10 min.Changes of HR、SBP、DBP were monitored before anesthesia,after induction,intubation and extubation,The changes in ST segment were recorded before anesthesia,after intubation and immediately after extubation.Results HR、SBP、DBP decreased significantly after induction compared with that of before anesthesia in two groups(P＜0.05,P＜0.01)while group D were lower than that of group C after intubation and immediately after extubation.The cases of ST segment showing myocardial injury were significantly differences between group D and group C(5 VS 1)(P＜0.05).Conclusion Dexmedetomidine intravenously could attenuate the degree of myocardial damage in elderly hypertension patients undergoing hip replacement surgery. Key words: Dexmedetomidine; Hypertension; Myocardial protection

Remote muscle salvage by regional substrate enhancement during on-bypass beating-heart treatment of cardiogenic shock

Surgical revascularization for postinfarction cardiogenic shock carries 20-50% mortality. Beating-heart techniques have been favoured, but their impact on the avoidance of additional myocardial injury is unknown. Ten consecutive patients with postinfarction cardiogenic shock, unsuitable anatomy for percutaneous coronary intervention (Syntax score 34.0±7.5; triple-vessel disease, 10/10; left main stenosis, 5/10), and no associated cardiac procedure, were selected for salvage/emergent on-pump beating-heart coronary bypass surgery. Remote muscle was sequentially substrate-enhanced reperfused through the grafts after construction of distal anastomoses. Early/late mortality, preoperative/peak postoperative enzyme release, and baseline/pre-discharge ventricular function were analysed. One early death occurred. Patients received 2.9±0.6 grafts, always employing the left internal mammary artery. Cardiopulmonary bypass duration was 140±62 min. Left ventricular ejection fraction (29.4±5.8 vs. 37.5±8.3%), wall motion score index (2.10±0.29 vs. 1.86±0.28), and end-systolic volume index (42.1±11.5 vs. 33.1±14.0 ml/m(2)) acutely improved (P≤0.001), whereas functional mitral regurgitation decreased from 1.4±0.8 to 0.8±0.4 (P=0.051). Total creatine kinase levels significantly increased (P=0.017), but myocardial band isoenzyme did not (P=0.18). After 3.1±1.4 years, eight patients are alive and seven are free of recurrent heart failure. Satisfactory functional outcome can be achieved with beating-heart on-pump revascularization for postinfarction cardiogenic shock. Perioperative enzyme releases and ventricular functional variables may suggest reduced perioperative myocardial injury.

Predictors of Cardiac Troponin Release After Mitral Valve Surgery

Although cardiac troponin I (cTnI) measurement is used extensively as a marker of perioperative myocardial injury, limited knowledge exists in noncoronary artery bypass graft surgery. Observational study. Single-center intensive care unit. None. One hundred eighty-five consecutive adult patients undergoing mitral valve surgery for predominant mitral regurgitation were enrolled and underwent measurement of cTnI at 24 hours after surgery. CTnI release after mitral valve surgery was significantly associated with an adverse outcome. The optimal cTnI value for predicting adverse outcomes was 14 ng/mL. Univariate preoperative predictors of cTnI release were prior use of diuretics (p = 0.04) or a rheumatic (p = 0.006), ischemic (p = 0.004), or myxomatous (p = 0.005) etiology to mitral disease, whereas intraoperative variables predictive of cTnI release were cross-clamp time (p = 0.005), cardiopulmonary bypass time (p < 0.001), need for mitral valve replacement (p = 0.024), number of electrical cardioversions (p = 0.03), patent foramen ovale closure (p = 0.03), tricuspid valve repair (p = 0.04), need for epinephrine/norepinephrine (p = 0.004) or intra-aortic balloon pump (p = 0.03) in the operating room; and, finally, the surgeon who performed the surgery (p = 0.014). There were no postoperative predictors of excessive cTnI release. In multivariate analysis, the only predictors of cTnI release were the cardiopulmonary bypass time (odds ratio, 1.42; confidence intervals, 1.019-1.064; p = 0.001) and the infusion of epinephrine/norepinephrine in the operating room (odds ratio, 4.002; confidence intervals, 1.238-12.929; p = 0.02). After mitral surgery, the need for epinephrine/norepinephrine perioperatively and the cardiopulmonary bypass time independently predict a cTnI release significantly related to an adverse outcome.

Chromosome 9p21 Variant Predicts Mortality After Coronary Artery Bypass Graft Surgery

Recent genome-wide association studies have identified several chromosome 9p21 single nucleotide polymorphisms associated with coronary artery disease and myocardial infarction in nonsurgical populations. We have recently demonstrated an independent association between these 9p21 variants and perioperative myocardial injury after isolated primary coronary artery bypass graft (CABG) surgery. This study investigated the association of a 9p21 variant with mortality in patients after CABG surgery and its prognostic value to improve the EuroSCORE. In a 2-center, prospective, observational study of 846 white primary CABG surgery patients, we genotyped rs10116277, the 9p21 variant with the strongest association to perioperative myocardial injury in our cohort. To estimate the utility of rs10116277 for predicting all-cause mortality within 5 years after surgery, a Cox proportional hazard model was constructed to estimate the hazard ratios (HR) and 95% confidence intervals (CI) while adjusting for demographics and clinical covariates. The homozygote minor allele of rs10116277 was associated with significantly increased risk of all-cause mortality even after adjusting for other clinical predictors of mortality in a Cox proportional hazards model (HR, 1.7; 95% CI, 1.1-2.7; P=0.026). Addition of rs10116277 to the logistic EuroSCORE also significantly improved model prediction for mortality (HR, 1.82; 95% CI, 1.15-2.88; P=0.01). The 9p21 variant rs10116277 is independently associated with all-cause mortality after primary CABG surgery in whites and significantly improves the predictive value of the logistic EuroSCORE. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00281164.

Revised Cardiac Risk Index (Lee) and Perioperative Cardiac Events as Predictors of Long-Term Mortality in Patients Undergoing Endovascular Abdominal Aortic Aneurysm Repair

Conclusion: Long-term mortality is high after endovascular repair of abdominal aortic aneurysm (AAA). In the setting of endovascular AAA repair, the Lee Index may be useful for stratifying short-term and long-term mortality in high-risk patients. Summary: Perioperative myocardial infarction remains a vexing problem. In very high-risk vascular surgical patients, perioperative myocardial ischemic injury may be as high as 18% to 35% (J Vasc Surg 2006;43:533-538). Although a large majority of patients survive a perioperative myocardial ischemic event, they are at risk of increased late mortality (J Vasc Surg 1994;20:598-604). Because it appears long-term survival is not improved by endovascular aneurysm repair (EVAR) vs conventional open AAA repair, it is reasonable to investigate whether patients undergoing EVAR can be stratified according to the Revised Cardiac Risk Index (Lee). This was a retrospective review from a single academic medical center involving 225 patients with AAA treated with EVAR between 1999 and 2006. The goal was to determine if the Lee Index is useful is stratifying patients by risk of both perioperative cardiac morbidity and long-term all-cause mortality. Data were collected from physician quality assurance databases, office records, and medical records. There were no in-hospital cardiac deaths. The major cardiac adverse event (MACE) rate perioperatively was 6.2%. Long-term all-cause mortality was 23%. By univariate analysis, a history of coronary artery disease (likelihood ratio [LR], 8.7; P = .023), history of congestive heart failure (LR, 4; P = .042), and a Revised Cardiac Risk Index (RCRI) ≥3 (LR, 8.6; P = .004) were all predictors of perioperative MACE. Long-term all-cause mortality was associated with a history of coronary artery disease (LR, 10.7; P = .002), perioperative cardiac events (LR, 15.9; P < .0001), echocardiographic evidence of myocardial infarction (LR, 8.5; P = .006), and exercise tolerance of only on block (LR, 8.4; P = .005). Long-term mortality is increased after perioperative cardiac events within the RCRI ≥3 subgroup (LR, 6.1; P = .019). Comment: It would seem logical that a patient who develops a myocardial ischemic event after EVAR should undergo further evaluation for coronary artery disease. Long-term survival appears significantly impaired after EVAR, and more so after even a minor myocardial infarction following EVAR. Whether the minor perioperative myocardial event is a cause of long-term mortality or merely a marker of long-term increased cardiac risk is a question that deserves further investigation.

Heart-Type Fatty Acid Binding Protein Is an Independent Predictor of Death and Ventricular Dysfunction After Coronary Artery Bypass Graft Surgery

Heart-type fatty acid binding protein (hFABP) functions as a myocardial fatty acid transporter and is released into the circulation early after myocardial injury. We hypothesized that hFABP is superior to conventional cardiac biomarkers for predicting early perioperative myocardial injury after coronary artery bypass graft (CABG) surgery. A prospective cohort study of 1298 patients undergoing primary CABG with cardiopulmonary bypass (CPB) was performed at 2 institutions. Four plasma myocardial injury biomarkers (hFABP; cardiac troponin I [cTnI]; creatine kinase, MB [CK-MB] fraction; and myoglobin) were measured at 7 perioperative time points. The association among perioperative cardiac biomarkers and ventricular dysfunction, hospital length of stay (HLOS), and up to 5-year postoperative mortality (median 3.3 years) was assessed using Cox proportional hazard models. We defined in-hospital ventricular dysfunction as a new requirement for 2 or more inotropes, or new placement of an intraaortic balloon pump, or ventricular assist device either during the intraoperative period after the patient separated from CPB or postoperatively in the intensive care unit. The positive and negative predictive values of mortality for hFABP are 13% (95% confidence interval [CI], 9%-19%) and 95% (95% CI, 94%-96%), respectively, which is higher than for cTnI and CK-MB. After adjusting for clinical predictors, both postoperative day (POD) 1 and peak hFABP levels were independent predictors of ventricular dysfunction (P < 0.0001), HLOS (P < 0.05), and 5-year mortality (P < 0.0001) after CABG surgery. Furthermore, POD1 and peak hFABP levels were significantly superior to other evaluated biomarkers for predicting mortality. In a repeated-measures analysis, hFABP outperformed all other models of fit for HLOS. Patients with POD2 hFABP levels higher than post-CPB hFABP levels had an increased mortality compared with those patients whose POD2 hFABP levels decreased from their post-CPB level (hazard ratio, 10.9; 95% CI, 5.0-23.7; P = 7.2 × 10(-10)). Mortality in the 120 patients (10%) with a later hFABP peak was 18.3%, compared with 4.7% in those who did not peak later. Alternatively, for cTnI or CK-MB, no difference in mortality was detected. Compared with traditional markers of myocardial injury after CABG surgery, hFABP peaks earlier and is a superior independent predictor of postoperative mortality and ventricular dysfunction.

Acute kidney injury after coronary artery bypass grafting: Does rhabdomyolysis play a role?

In clinical situations in which rhabdomyolysis is common, renal dysfunction association with myoglobinemia is well described. After coronary artery bypass grafting, a rapid increase in serum myoglobin concentration is generally seen, but whether it might independently increase the risk of acute kidney injury remains to be determined. The study population consisted of 731 consecutive patients undergoing coronary artery bypass grafting. Creatine kinase, myoglobin, and creatinine concentrations were assessed in each patient preoperatively and postoperatively. Acute kidney injury was defined as an absolute increase in serum creatinine concentration of 0.3 mg/dL or greater. Overall, 295 (40.3%) of 731 patients had acute kidney injury. Patients' risk profiles were significantly worse in those with acute kidney injury, and 31 (4.2%) of 731 patients required dialysis. Acute kidney injury was associated with a higher increase in serum myoglobin concentration after 1 hour from aortic declamping (534 microg/mL [interquantile range, 354-733 microg/mL] vs 377 microg/mL [interquantile range, 278-528 microg/mL], P < .0001), which persisted at 24 and at 48 hours. After adjusting for confounding factors, myoglobin concentration was found to independently predict postoperative acute kidney injury (odds ratio, 1.0011 [1 microg/mL increase]; 95% confidence interval, 1.0003-1.0019; P = .005), and this result persisted when patients with perioperative myocardial infarction were excluded from the analysis (odds ratio, 1.0007; 95% confidence interval, 1.0002-1.0009; P = .01). Myoglobin concentration had a better accuracy to discriminate patients having acute kidney injury than creatine kinase concentration at any time. An increase in laboratory findings of muscle injury postoperatively, especially serum myoglobin concentration, predicts the incidence of acute kidney injury and renal replacement therapy requirement, as reported in other surgical settings. Perioperative myocardial injury cannot totally explain the occurrence of increased myoglobinemia. These results suggest an important role of skeletal muscle breakdown and necrosis in determining an increased myoglobinemia concentration after coronary artery bypass grafting.