Kinetics of Highly Sensitive Troponin T after Cardiac Surgery. Biomed Res Int. 2015;2015:574546. [PMID: 26539512 PMCID: PMC4619841 DOI: 10.1155/2015/574546]

Prognostic Value of High-Sensitivity Troponin T After On-Pump Coronary Artery Bypass Graft Surgery

INTRODUCTION

High-sensitivity troponin T (hs-TnT), as a single or serial measurement to predict postoperative mortality and morbidity, appears to be attractive due to its direct relationship in assessing myocardial damage and the widespread availability of hs-TnT testing. Therefore, this study aimed to identify any prognostic value of hs-TnT in predicting in-hospital outcomes after coronary artery bypass graft (CABG) surgery.

METHOD

We identified all consecutive patients who underwent on-pump CABG between July 2011 and December 2018. To evaluate the prognostic value of hs-TnT after CABG, we assessed the probability and odds ratio (OR) of adverse events concerning the maximum value of postoperative hs-TnT (measured within 24 hrs). TnT was routinely collected at 0, 6, 12 and 72 hours postoperatively. Values were categorised into intervals of 200 for analysis. A fully Bayesian logistic regression of the adverse event with the troponin T interval (0-200) as the reference level was used. A subgroup analysis was performed in patients with normal and elevated preoperative hs-TnT (< or ≥30 ng/L). The pre-specified primary outcome was a major adverse cardiac or cerebrovascular event (MACCE), defined as a composite of death within 30 days of operation for any cause, myocardial infection (MI), or stroke.

RESULTS

1,318 people underwent on-pump CABG during this period. One hundred and twenty-three (123) (9.3%) experienced MACCE, 14 (1.1%) experienced death within 30 days, 105 (8.0%) experienced MI and 14 (1.1%) experienced stroke. Compared to the reference category (hs-TnT ≤200 ng/L) we found there was an increase in OR with increasing level of hs-TnT for MACCE (p<0.001), 30-day mortality (p=0.003), MI (p<0.001) and ICU stay >48 hours (p<0.001). However, there was no statistically significant association present between hs-TnT and stroke, readmission to the intensive care unit (ICU), return to theatre for bleeding, or new-onset renal dysfunction.

CONCLUSION

Peak hs-TnT level, greater than 400 ng/L, measured within 24 hours after CABG surgery is associated with MACCE, 30-day mortality, MI and ICU stay >48 hours. Prospectively designed trials, with clear prognostic and outcome variables, may provide further insight into the prognostic value of hs-TnT post-CABG.

Intensive care outcome of left main stem disease surgery: A single center three years’ experience

BACKGROUND

Left main coronary artery (LMCA) supplies more than 80% of the left ventricle, and significant disease of this artery carries a high mortality unless intervened surgically. However, the influence of coronary artery bypass grafting (CABG) surgery on patients with LMCA disease on morbidity intensive care unit (ICU) outcomes needs to be explored. However, the impact of CABG surgery on the morbidity of the ICU population with LMCA disease is worth exploring.

AIM

To determine whether LMCA disease is a definitive risk factor of prolonged ICU stay as a primary outcome and early morbidity within the ICU stay as secondary outcome.

METHODS

Retrospective descriptive study with purposive sampling analyzing 399 patients who underwent isolated urgent or elective CABG. Patients were divided into 2 groups; those with LMCA disease as group 1 (75 patients) and those without LMCA disease as group 2 (324 patients). We correlated ICU outcome parameters including ICU length of stay, post-operative atrial fibrillation, acute kidney injury, re-exploration, perioperative myocardial infarction, post-operative bleeding in both groups.

RESULTS

Patients with LMCA disease had a significantly higher prevalence of diabetes (43.3% vs 29%, P = 0.001). However, we did not find a statistically significant difference with regards to ICU stay, or other morbidity and mortality outcome measures.

CONCLUSION

Post-operative performance of Patients with LMCA disease who underwent CABG were comparable to those without LMCA involvement. Diabetes was more prevalent in patients with LMCA disease. These findings may help in guiding decision making for future practice and stratifying the patients’ care.

High-sensitivity cardiac troponin release after conventional and minimally invasive cardiac surgery

After cardiac surgery, a certain degree of myocardial injury is common. The arbitrarily proposed biomarker cut-off point in the Third Universal Definition for diagnosing coronary artery bypass grafting (CABG)–related perioperative myocardial infarction (PMI) is controversial and unvalidated for non-CABG surgery. Minimally invasive cardiac surgery is often thought to be associated with less myocardial damage compared to conventional surgical approaches. We conducted a real-life prospective study with serial sampling of high-sensitivity cardiac troponin T (hs-cTnT) in patients undergoing conventional and minimally invasive cardiac surgery. Four different types of cardiac surgery were performed in 400 patients (February 2014–January 2015): CABG, aortic valve replacement, minimally invasive mitral/tricuspid valve surgery through the HeartPort (HP) technique and combined CABG/valve surgery. Each group was further subdivided for comparison between the different surgical techniques. Blood samples were collected consecutively at intensive care unit (ICU) admission and 3, 6, 9, 12, 18, 24 and 48 h thereafter. The hs-cTnT values by peak timepoint differed significantly depending on the surgical approach. The overall peak timepoint for hs-cTnT occurred 6 h after ICU admission. The combined surgery and multiple-valve HP groups had the highest values (medians of 1067.5 (744.9–1455) ng/L and 1166 (743.7–2470) ng/L, respectively). The peak hs-cTnT values for patients developing PMI showed high variability. Differentiation between cardiac surgery–related necrosis and PMI remains challenging. This study emphasizes the importance of a clinically reliable biomarker cut-off value in addition to electrocardiography and echocardiography to optimize PMI diagnosis.

Biomarkers in the Diagnosis, Management, and Prognostication of Perioperative Right Ventricular Failure in Cardiac Surgery-Are We There Yet?

Right ventricular failure (RVF) is a major risk factor for end organ morbidity and mortality following cardiac surgery. Perioperative RVF is difficult to predict and detect, and to date, no convenient, accurate, or reproducible measure of right ventricular (RV) function is available. Few studies have examined the use of biomarkers in RVF, and even fewer have examined their utility in the perioperative setting of patients undergoing cardiac surgery. Of the available classes of biomarkers, this review focuses on biomarkers of (1) inflammation and (2) myocyte injury/stress, due to their superior potential in perioperative RV assessment, including Galectin 3, ST2/sST2, CRP, cTN/hs-cTn, and BNP/NT-proBNP. This review was performed to help highlight the importance of perioperative RV function in patients undergoing cardiac surgery, to review the current modalities of RV assessment, and to provide a review of RV specific biomarkers and their potential utilization in the clinical and perioperative setting in cardiac surgery. Based on current evidence, we suggest the potential utility of ST2, sST2, Gal-3, CRP, hs-cTn, and NT-proBNP in predicting and detecting RVF in cardiac surgery patients, as they encompass the multifaceted nature of perioperative RVF and warrant further investigation to establish their clinical utility.

Clinical Relevance of Troponin T Profile Following Cardiac Surgery

Background: Peak post-operative cardiac troponin T (cTnT) independently predicts mid- and long-term outcome of cardiac surgery patients. A few studies however have reported two peaks of cTnT over the first 48–72 h following myocardial reperfusion. The aim of the current study was to better understand underlying reasons of these different cTnT profiles and their possible relevance in terms of clinical outcome.

Methods: All consecutive adult cardiac surgical procedures performed with an extra-corporeal circulation during a >6 years period were retrospectively evaluated. Patients with a myocardial infarction (MI) < 8 days were excluded. cTnT profile of patients with at least one value ≥1 ng/mL value were categorized according to the time occurrence of the peak value. Univariable and multivariable analysis were performed to identify factors influencing early vs. late increase of cTnT values, and to verify the correlation of early vs. late increase with clinical outcome.

Results: Data of 5,146 patients were retrieved from our prospectively managed registry. From 953 with at least one cTnT value ≥1 ng/mL, peak occurred ≤ 6 h (n = 22), >6 to ≤ 12 h (n = 366), >12 to ≤ 18 h (n = 176), >18 to ≤ 24 h (171), >24 h (218). Age (OR: 1.023; CI: 1.016–1.030) and isolated CABG (OR: 1.779; CI: 1.114–2.839) were independent predictors of a late increase of cTnT over a limit of 1 ng/ml (p < 0.05), whereas isolated valve procedures (OR: 0.685; CI: 0.471–0.998) and cross-clamp duration (OR: 0.993; CI: 0.990–0.997) independently predicted an early elevation (p < 0.05). Delayed elevation as opposed to early elevation correlated with a higher rate of post-operative complications including MI (19.8 vs. 7.2%), new renal insufficiency (16.3 vs. 6.7%), MACCE (32.0 vs. 15.5%), or death (7.4 vs. 4.4%).

Conclusion: Profile of cTnT elevation following cardiac surgery depends on patients' intrinsic factors, type of surgery and duration of cross-clamp time. Delayed increase is of higher clinically relevance than prompt post-operative elevation.

Acute kidney injury induces high-sensitivity troponin measurement changes after cardiac surgery

BACKGROUND

The value of cardiac troponin as a risk assessment tool for cardiac disease in the setting of end-stage renal diseases (ESRD) is not equivalent to its value in those with normal renal function. This consideration had not been studied in settings of acute kidney injury (AKI). We aim to explore the diagnostic value of high sensitive troponin T (hsTnT) in the settings of cardiac surgery-induced AKI.

METHODS

Single center observational retrospective study. Based on the AKI Network, patients divided into 2 groups, group I without AKI (259 patients) and group II with AKI (100 patients) where serial testing of hsTnT and creatine kinase (CK)-MB were followed in both groups. Patients with (ESRD) were excluded.

RESULTS

The mean age in our study was 55.1 ± 10.2 years. High association of AKI (27.8%) was found in our patients. Both groups were matched regarding the age, gender, body mass index, the association of diabetes or hypertension, and Euro score. AKI group had significantly higher mortality 5% vs group I 1.1% (p = 0.03). The hsTnt showed a significant sustained rise in the AKI group as compared to the non-AKI group, however CK-MB changes were significant initially but not sustained. The AKI group was more associated with heart failure 17.9% vs 4.9% (p = 0.001); and post-operative atrial fibrillation, 12.4% vs 2.9% (p = 0.005). Lengths of ventilation, stays in ICU and in hospital were significantly higher in the AKI group.

CONCLUSIONS

Unlike the CK-MB profile, the hsTnT showed significant changes between both groups all over the course denoting possible delayed clearance in patients with AKI.