Clinical Relevance of Cardiac Troponin Assessment in Patients Undergoing Carotid Endarterectomy

Incidence of myocardial injury in patients submitted to carotid endarterectomy

Myocardial injury following noncardiac surgery (MINS) is associated with higher mortality and major adverse cardiovascular event rates in the short- and long-term in patients undergoing carotid endarterectomy (CEA). However, its incidence is still unclear in this subset of patients. Therefore, this systematic review with meta-analysis aims to determine the incidence of MINS in patients undergoing CEA. Three electronic databases MEDLINE, Scopus, and Web of Science were used to search for studies assessing the occurrence of MINS in the postoperative setting of patients undergoing CEA. The incidence of MINS was pooled by random-effects meta-analysis, with sources of heterogeneity being explored by meta-regression and subgroup analysis (general anesthesia vs. regional anesthesia). Assessment of studies' quality was performed using National Heart, Lung, and Blood Institute Study Quality Assessment Tool, and Risk of Bias 2 tools. Twenty studies were included, with a total of 117,933 participants. Four of them were RCTs, while the remaining were cohort studies. All observational cohorts had an overall high risk of bias, except for Pereira Macedo et al. Three of them had repeated population, thus only data from the most recent one was considered. On the other hand, all RCT had an overall low risk of bias. In patients under regional anesthesia, the incidence of MINS in primary studies ranged between 2% and 15.3%, compared to 0-42.5% for general anesthesia. The meta-analytical incidence of MINS after CEA was of 6.3% [95% CI 2.0-10.6%], but severe heterogeneity was observed (I2=99.1%). MINS appears to be relatively common among patients undergoing CEA. The observed severe heterogeneity points to the need for further larger studies adopting consistent definitions of MINS and equivalent cut-off values.

Contralateral Carotid Stenosis is a Predictor of Long-term Adverse Events in Carotid Endarterectomy

Contralateral carotid stenosis (clCS) has been described as a perioperative predictor of mortality after carotid endarterectomy (CEA). However, its predictive value on long-term cardiovascular events remains controversial. The study aims to assess the potential role of clCS as a long-term predictor of major adverse cardiovascular events (MACE) in patients who underwent CEA. From January 2012 to July 2020, patients undergoing CEA under regional anesthesia for carotid stenosis in a tertiary care and referral center were eligible from a prospective database, and a post hoc analysis was performed. The primary outcome consisted in the occurrence of long-term MACE. Secondary outcomes included all-cause mortality, stroke, myocardial infarction, acute heart failure, and major adverse limb events. A total of 192 patients were enrolled. With a median 50 months follow-up, chronic kidney disease (CKD) (mean survival time (MST) 51.7 vs. 103.3, p<0.010) and peripheral artery disease (PAD) (MST 75.1 vs. 90.3, p=0.001) were associated with decreased survival time. After propensity score matching (PSM), CKD (MST 49.1 vs. 106.0, p=0.001) and PAD (MST 75.7 vs. 94.0, p=0.001) maintained this association. On multivariate Cox regression analysis, contralateral stenosis was associated with higher MACE (hazard ratio (HR) = 2.035; 95% CI: 1.113-3.722, p=0.021 and all-cause mortality (HR = 2.564; 95% CI: 1.276-5,152 p=0.008). After PSM, only all-cause mortality (HR 2.323; 95% CI: 0.993-5.431, p=0.052) maintained a significant association with clCS. On multivariable analysis, clCS (aHR 2.367; 95% CI: 1.174-4.771, p=0.016), age (aHR 1.039, 95% CI: 1.008-1.070), CKD (aHR 2.803; 95% CI: 1.409-5.575, p=0.003) and PAD (aHR 3.225, 95% CI: 1.695-6.137, p<0.001) were independently associated with increased all-cause mortality. Contrary to MACE, clCS is a strong predictor of long-term all-cause mortality after CEA. However, MACE risk may compromise CEA benefits by other competitive events. Therefore, further studies are needed to establish the role of clCS on postoperative events and on patients' specific assessments in order to determine the best medical treatment and easy access to surgical intervention.

Increased serum level of high sensitivity troponin T even prior to surgery can predict adverse events during carotid endarterectomy

OBJECTIVES

Perioperative stress affects the outcome of carotid endarterectomy performed under regional anesthesia. Here we aimed to explore the temporal profile of the stress marker cortisol and its relationship to high-sensitivity troponin-T, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1, and S100B as an indicator of blood-brain barrier alteration in the systemic circulation.

METHODS

Prospective part of the study: a total of 31 patients with significant carotid stenosis scheduled for carotid endarterectomy in regional anesthesia were enrolled. Follow-up part of the study and retrospective analysis of the outcome: each patient was followed up to five years and morbidity as well as mortality data were collected from an electronic database. Blood samples from each patient were serially taken; prior to surgery (T1), at the time of reperfusion (T2), 24 h (T3) and 72 h later postoperatively (T4), then the plasma concentration of each biomarker was measured. Besides, the clinical and surgical factors and perioperative adverse events were recorded.

RESULTS

More positive correlations were found between: the early change of S100B (T2-T1) and late change in plasma cortisol level (T4-T3) (r = 0.403; p < 0.05); the early change of cortisol (T2-T1) and the early postoperative change of plasma matrix metalloproteinase-9 level (T3-T2) (r = 0.432; p = 0.01); the plasma concentration of tissue inhibitor of metalloproteinase-1 at 24 postoperative hours and the late change in plasma high-sensitivity troponin-T level (T4-T3) (r = 0.705; p < 0.001). Five patients needed an intraoperative shunt in whom the high-sensitivity troponin-T was elevated even prior to surgery, but definitive stroke never occurred. Plasma matrix metalloproteinase-9 concentration at reperfusion independently predicted the five-year mortality with a cut-off value of 456 ng/ml (sensitivity: 86%, specificity: 84%, area 0.887, p = 0.002).

CONCLUSIONS

A higher intraoperative change in S100B level reflecting carotid endarterectomy induced acute silent brain ischemia was associated with more pronounced post-operative change of cortisol. An early elevation of cortisol was found to be associated with a delayed increase of matrix metalloproteinase-9. Importantly, an increased high-sensitivity troponin-T even prior to carotid endarterectomy may predict clamp intolerance, and elevated matrix metalloproteinase-9 at reperfusion suggests a poor outcome.

Red Blood Cell Distribution Width as a 5-Year Prognostic Marker in Patients Submitted to Carotid Endarterectomy

OBJECTIVE

Patients submitted to carotid artery endarterectomy (CEA) have a long-term risk of major adverse cardiovascular events (MACE) of 6-9% at 2 years. Hematological parameters have been shown to have a predictive function in atherosclerotic diseases, namely the red blood cell distribution width-coefficient of variation (RDW-CV). This parameter has been associated with worse outcomes such as myocardial infarction (MI), stroke, and all-cause mortality. This study aims to evaluate the potential role of preoperative hematologic parameters such as RDW-CV in predicting perioperative and long-term cardiovascular adverse events and mortality in patients submitted to CEA.

METHODS

From January 2012 to January 2019, 180 patients who underwent CEA with regional anesthesia in a tertiary care and referral center were selected from a prospective cohort database. Blood samples were collected preoperatively 2 weeks before admission, including a full blood count. The primary outcome included long-term MACE. Secondary outcomes included all-cause mortality, stroke, MI, acute heart failure, and major adverse limb events (MALE).

RESULTS

At baseline, 27.2% of patients had increased RDW-CV. Increased RDW-CV was independently associated with baseline hemoglobin (adjusted odds ratio [aOR] 0.715, 95% CI 0.588-0.869, p = 0.001) and atrial fibrillation (aOR 4.028, 95% CI 1.037-15.639, p = 0.001). After a median follow-up of 50 months, log-rank univariate analysis of RDW-CV demonstrated a significant association between increased RDW-CV and long-term all-cause mortality (log-rank <0.001), MACE (log-rank <0.001), and MI (log-rank = 0.017). After multivariate Cox regression analysis, increased RDW-CV was associated with increased long-term mortality (adjusted hazard ratio [aHR] 2.455, 95% CI 1.231-4.894, p = 0.011) and MACE (aHR 2.047, 95% CI 1.202-3.487, p = 0.008). A decreased hemoglobin to platelet ratio (aHR 2.650e-8, 95% CI 9.049e-15 to 0.078, p = 0.019) was also associated with all-cause mortality.

CONCLUSION

RDW is a widely available and low-cost marker that independently predicts long-term mortality, MACE, and MI after CEA. This biomarker could prove useful in assessing which patients would likely benefit from CEA in the long term.

Reticulated Platelets as Predictor of Myocardial Injury and 30 Day Mortality After Non-cardiac Surgery

OBJECTIVE

A pre-operative marker for identification of patients at risk of peri-operative adverse events and 30 day mortality might be the percentage of young, reticulated platelets (pRP). This study aimed to determine the predictive value of pre-operative pRP on post-operative myocardial injury (PMI) and 30 day mortality, in patients aged ≥ 60 years undergoing moderate to high risk non-cardiac surgery.

METHODS

The incidence of PMI (troponin I > 0.06 μg/L) and 30 day mortality was compared for patients with normal and high pRP (≥2.82%) obtained from The Utrecht Patient Orientated Database. The predictive pRP value was assessed using logistic regression. A prediction model for PMI or 30 day mortality with known risk factors was compared with a model including increased pRP using the area under the receiving operator characteristics curve (AUROC).

RESULTS

In total, 26.5% (607/2289) patients showed pre-operative increased pRP. Increased pRP was associated with more PMI and 30 day mortality compared with normal pRP (36.1% vs. 28.3%, p < .001 and 8.6% vs. 3.6%, p < .001). The median pRP was higher in patients suffering PMI and 30 day mortality compared with not (2.21 [IQR: 1.57-3.11] vs. 2.07 [IQR: 1.52-1.78], p = .002, and 2.63 [IQR: 1.76-4.15] vs. 2.09 [IQR: 1.52-3.98], p < .001). pRP was independently related to PMI (OR: 1.28 [95% CI: 1.04-1.59], p = .02) and 30 day mortality (OR: 2.35 [95% CI: 1.56-3.55], p < .001). Adding increased pRP to the predictive model of PMI or 30 day mortality did not increase the AUROC 0.71 vs. 0.72, and 0.80 vs. 0.81.

CONCLUSION

In patients undergoing major non-cardiac surgery, increased pre-operative pRP is related to 30 day mortality and PMI.

Risk factors of postoperative major adverse cardiac events after radical cystectomy: implication of diastolic dysfunction

Radical cystectomy, which is a standard treatment of muscle invasive and high-grade non-invasive bladder tumour, is accompanied with high rates of postoperative complications including major adverse cardiac events (MACE). Diastolic dysfunction is associated with postoperative complications. We evaluated perioperative risk factors including diastolic dysfunction related with MACE within 6 months after radical cystectomy. The 546 patients who underwent elective radical cystectomy were included. Diastolic dysfunction was defined as early transmitral flow velocity (E)/early diastolic mitral annulus velocity (e′) > 15. Logistic regression analysis, Kaplan-Meier survival analysis and log-rank test were performed. MACE within 6 months after radical cystectomy developed in 43 (7.9%) patients. MACE was related with female (odds ratio 2.546, 95% confidence interval 1.166–5.557, P = 0.019) and diastolic dysfunction (odds ratio 3.077, 95% confidence interval 1.147–8.252, P = 0.026). The 6-month mortality were significantly higher in the MACE group, and hospital stay and intensive care unit stay were significantly longer in the MACE group compared to the non-MACE group. Accordingly, preoperative diastolic dysfunction (E/e′ > 15) was related with postoperative MACE and MACE was related with 6-month survival after radical cystectomy. These results suggest that preoperative diastolic dysfunction can provide useful information on postoperative complications.

Prevalence and risk factors of subclinical coronary artery disease in patients undergoing carotid endarterectomy: a retrospective cohort study

BACKGROUND

Coronary artery disease (CAD) is closely associated with carotid artery stenosis in the context of systemic arteriosclerosis, and it is a known perioperative risk factor for carotid endarterectomy (CEA). We aimed to evaluate the prevalence and risk factors of subclinical CAD in patients without known CAD undergoing CEA.

METHODS

This was a single-center, retrospective, observational study conducted between January 2013 and December 2016. Among the patients scheduled for elective CEA, 69 with no medical history of CAD and no clinical symptoms (mean age, 76.4±7.8 years; 71.0% men) underwent coronary computed tomography (CT). Coronary angiography (CAG) and subsequent fractional flow reserve (FFR) estimation were performed if necessary. Subclinical CAD was defined as newly found significant coronary lesions after coronary CT screening. Significant coronary lesions were defined as lesions that showed total or subtotal occlusion on coronary CT, had ≥75% stenosis on CAG, or had FFR≤0.80 in major coronary arteries.

RESULTS

The prevalence of subclinical CAD was 17.4% (12 of 69 patients). Among the patient characteristics assessed, only high-density lipoprotein cholesterol (HDL-C) levels were significantly different between patients with and those without subclinical CAD (45.8±10.1 vs. 59.7±16.7 mg/dL, P=0.0072). A multivariate analysis revealed that low HDL-C levels were independent risk factors for subclinical CAD after adjusting for possible confounders (adjusted odds ratio: 0.91, 95% confidence interval: 0.84-0.98, P=0.0099).

CONCLUSIONS

Subclinical CAD is a common finding and is associated with low HDL-C in patients without known CAD undergoing CEA.

Clinical and surrogate endpoints in future studies on outcome of carotid revascularization

This paper will provide a comparison of classical endpoints like stroke and mortality versus biochemical (non-STEMI) myocardial infarction and DW-MRI new brain lesions and will discuss the importance of cranial nerve lesion in CEA. An overview of possible endpoints of future randomized clinical trials will be given.

Routine Postoperative Cardiac Testing is Unnecessary after Carotid Endarterectomy

BACKGROUND

Routine laboratory testing to rule out myocardial infarction (MI) after carotid endarterectomy (CEA) is common in many centers. Its use in this patient population has not been thoroughly investigated. We hypothesize that routine testing for MI in post-CEA patients is of low yield and not cost-effective.

METHODS

A retrospective review of 291 consecutive CEAs from February 2011 to July 2015 was performed. Two patients were excluded: one for postoperative noncardiac death and one for preoperative MI. Patient demographics, medications, medical history, type of anesthesia, and postoperative laboratory results were reviewed. All patients had troponin-I and creatine kinase-MB levels taken postoperatively. A patient was judged to have an MI if troponin-I was greater than or equal to 0.6 ng/mL or CK-MB is >6.3 ng/mL. The incidence of postoperative MI was recorded, and a cost analysis was performed.

RESULTS

The mean age was 70.2 years (range: 42-92). Of all, 59.5% were male, and 92.4% had a history of hypertension. Preoperatively, 57.4% were on beta-blocker therapy, 86.5% on aspirin, and 52.2% on both. Most (80.6%) were on preoperative statin therapy, 26.9% had a prior history of MI (37.2% within 5 years of surgery), and 56.4% of patients had a prior coronary intervention (27.6% percutaneous, 28.7% coronary artery bypass grafting, and 11% both). All patients received general anesthesia. The mean procedure time was 121.5 min (range: 62-258). The mean postoperative length of stay was 2.6 days. Eight patients (2.7%) were judged to have acute MI, one of which was symptomatic. Three of the 8 (38%) had a prior history of MI. In asymptomatic patients, the peak level of troponin-I ranges from 0.52 to 3.64 ng/mL and that of CK-MB from 11.8 to 24 ng/mL. The symptomatic patient had chest pain and bradycardia. The patient had a peak troponin-I level of 1.59 ng/mL, with a CK-MB level of 11.5 ng/mL. All patients were treated medically. The cost per troponin-I and CK-MB is $27.78 and $31.44, respectively, in our institution. We estimate that eliminating routine postoperative troponin-I and CK-MB testing in patients who underwent CEA would have saved an estimated $51,343 over the course of treatment of the studied population.

CONCLUSIONS

Routine postoperative cardiac laboratory testing in asymptomatic patients after CEA increases the hospital cost. The low overall rate of postoperative MI suggests that cardiac testing is best reserved for symptomatic patients or those with clinical suspicion for MI.