Troponin Marker for Acute Coronary Occlusion and Patient Outcome Following Cardiac Arrest

The Association between Troponin-I Clearance after the Return of Spontaneous Circulation and Outcomes in Out-of-Hospital Cardiac Arrest Patients

Background

Elevated levels of troponin-I (TnI) are common in out-of-hospital cardiac arrest (OHCA) patients. However, studies evaluating the prognostic value of TnI clearance in OHCA patients are lacking. We aimed to examine how TnI clearance (TnI-C) differed according to the neurological outcome group and mortality group at 6 months.

Methods

This retrospective observational study involved adults ( ≥ 18 years) who were treated for an OHCA between January 2019 and December 2022. The TnI-Cs were calculated for days 1 to 2 (TnI-C1st) and 2 to 3 (TnI-C2nd) after the return of spontaneous circulation (ROSC). The primary outcome was a poor neurological outcome at 6 months, defined by cerebral performance categories 3, 4, and 5. The secondary outcome was 6-month mortality.

Results

A total of 227 patients were included. A poor neurological outcome and mortality at 6-months were reported in 150 (66.1%) and 118 (52.0%) patients, respectively. The TnI-C1st was significantly lower in patients with a poor outcome compared with good outcome patients (neurological outcome at 6 months, 54.4% vs. 42.3%; 6-month mortality, 52.1% vs. 42.7%, respectively). In the multivariable analyses, a TnI-C1st < 50% was associated with a poor neurological outcome (odds ratio [OR] 2.078, 95% confidence interval [CI] 1.080-3.995, p = 0.028) and mortality (OR 2.131, 95% CI 1.114-4.078, p = 0.022) at 6 months.

Conclusions

After ROSC, TnI-C1st < 50% was associated with a poor neurological outcome and mortality at 6 months in OHCA patients.

Emergency Department Point-of-Care Tests during Cardiopulmonary Resuscitation to Predict Cardiac Arrest Outcomes

Introduction

This study evaluated the role of point-of-care tests (POCT) such as blood lactate, anion gap (AG), base deficit, pH, N-terminal pro B-type natriuretic peptide (NT-proBNP), and troponin as the predictors of cardiac arrest outcomes in the emergency department (ED).

Methods

We conducted a prospective, observational study in the ED of a tertiary care hospital in India. All the adult patients who received cardiopulmonary resuscitation (CPR) in the ED were included in the study. Blood samples were collected within 10 min of initiation of CPR for assay of POCTs. Outcomes assessed were the return of spontaneous circulation (ROSC), 24-h survival, survival to hospital discharge (STHD), survival at 7 days, and favorable neurological outcome (FNO) at day 7 of admission.

Results

One hundred and fifty-one patients were included in the study (median age: 50 years, 65% males). Out of 151 cases, ROSC, survival at 7 days, STHD, and FNO was observed in 86 patients, six patients, five patients, and two patients, respectively. "No-ROSC" could be significantly predicted by raised lactate (odds ratio [OR]: 1.14, 95% confidence interval: 1.07-1.22) and NT-proBNP (OR: 1.05, 1.01-1.09) values at the time of cardiac arrest. "24-h mortality" could be significantly predicted by the raised lactate (OR: 1.14, 1.01-1.28), low arterial pH (OR: 0.05, 0.01-0.52), raised AG (OR: 1.08, 1.01-1.15), and lower base deficit (<-15) (OR: 1.07, 1.01-1.14). None of the other POCTs was found to be a predictor of other cardiac arrest outcomes.

Conclusion

Among various POCTs, raised lactate assayed within 10 min of cardiac arrest can predict poor outcomes like "no-ROSC" and 24-h mortality.

Prognostic Value of Cardiac Troponin I in Patients with Ventricular Tachyarrhythmias

Besides the diagnostic role in acute myocardial infarction, cardiac troponin I levels (cTNI) may be increased in various other clinical conditions, including heart failure, valvular heart disease and sepsis. However, limited data are available regarding the prognostic role of cTNI in the setting of ventricular tachyarrhythmias. Therefore, the present study sought to assess the prognostic impact of cTNI in patients with ventricular tachyarrhythmias (i.e., ventricular tachycardia (VT) and fibrillation (VF)) on admission. A large retrospective registry was used, including all consecutive patients presenting with ventricular tachyarrhythmias from 2002 to 2015. The prognostic impact of elevated cTNI levels was investigated for 30-day all-cause mortality (i.e., primary endpoint) using Kaplan–Meier, receiver operating characteristic (ROC), multivariable Cox regression analyses and propensity score matching. From a total of 1104 patients with ventricular tachyarrhythmias and available cTNI levels on admission, 46% were admitted with VT and 54% with VF. At 30 days, high cTNI was associated with the primary endpoint (40% vs. 22%; log rank p = 0.001; HR = 2.004; 95% CI 1.603–2.505; p = 0.001), which was still evident after multivariable adjustment and propensity score matching (30% vs. 18%; log rank p = 0.003; HR = 1.729; 95% CI 1.184–2.525; p = 0.005). Significant discrimination of the primary endpoint was especially evident in VT patients (area under the curve (AUC) 0.734; 95% CI 0.645–0.823; p = 0.001). In contrast, secondary endpoints, including all-cause mortality at 30 months and a composite arrhythmic endpoint, were not affected by cTNI levels. The risk of cardiac rehospitalization was lower in patients with high cTNI, which was no longer observed after propensity score matching. In conclusion, high cTNI levels were associated with increased risk of all-cause mortality at 30 days in patients presenting with ventricular tachyarrhythmias.

Coronary angiography in patients after cardiac arrest without ST-elevation myocardial infarction : A retrospective cohort analysis

BACKGROUND

Coronary artery disease (CAD) is the most common cause of sudden cardiac arrest (SCA). Although coronary angiography (CAG) should be performed also in the absence of ST-elevation (STE) after sustained return of spontaneous circulation (ROSC), this recommendation is not well implemented in daily routine.

METHODS

A retrospective database analysis was conducted in a tertiary care center between January 2005 and December 2014. We included all SCA patients aged ≥ 18 years with presumed cardiac cause and sustained ROSC in the absence of STE at hospital admission. The rate and timing of CAG were defined as the primary endpoints. As secondary endpoints, the reasons pro and contra CAG were analyzed. Furthermore, we observed if the signs and symptoms used for decision making occurred more often in patients with treatable CAD.

RESULTS

We included 645 (53.6%) of the 1203 screened patients, CAG was performed in 343 (53.2%) patients with a diagnosis of occlusive CAD in 214 (62.4%) patients. Of these, 151 (71.0%) patients had occlusive CAD treated with coronary intervention, thrombus aspiration, or coronary artery bypass grafting. In an adjusted binomial logistic regression analysis, age ≥ 70 years, female sex, non-shockable rhythms, and cardiomyopathy were associated with withholding of CAG. In patients diagnosed and treated with occlusive CAD, initially shockable rhythms, previously diagnosed CAD, hypertension, and smoking were found more often.

CONCLUSION

Although selection bias is unavoidable due to the retrospective design of this study, a high proportion of the examined patients had occlusive CAD. The criteria used for patient selection may be suboptimal.

ST-Elevation Myocardial Infarction Complicated by Out-of-Hospital Cardiac Arrest

5-10% of ST-elevated myocardial infarctions (STEMI) present with out-of-hospital cardiac arrest (OHCA). Although this subgroup of patients carries the highest in-hospital mortality among the STEMI population, it is the least likely to undergo coronary angiography and revascularization. Due to the concomitant neurologic injury, patients with OHCA STEMI require prolonged hospitalization and adjustments to standard MI management. This review systematically assesses the course of patients with OHCA STEMI from development of the arrest to hospital discharge, assesses the limiting factors for their treatment access, and presents the evidence-based optimal intervention strategy for this high-risk MI population.

Diagnostic test accuracy of the initial electrocardiogram after resuscitation from cardiac arrest to indicate invasive coronary angiographic findings and attempted revascularization: A systematic review and meta-analysis

AIM

Conduct a diagnostic test accuracy systematic review and meta-analysis of the post-return of spontaneous circulation (ROSC) electrocardiogram (ECG) to indicate an acute-appearing coronary lesion and revascularization.

METHODS

We searched PubMed, EMBASE, CINAHL, Cochrane Library, and Web of Science through February 18, 2020. Two investigators screened titles and abstracts, extracted data, and assessed risks of bias using QUADAS-2. We estimated sensitivity (Sn), specificity (Sp), and likelihood ratios (LR) for all reported ECG features to indicate all reported reference standards. Random-effects meta-analysis pooled comparable studies without critical risk of bias. GRADE methodology evaluated the certainty of evidence.

RESULTS

Overall, 48 studies reported 94 combinations of ECG features and reference standards with wide variation in their definitions. Most studies had risks of bias from selection for coronary angiography and blinding to the ECG and/or reference standard. Meta-analysis combined 6 studies for STE and acute coronary lesion (Sn 0.70 [95% CI 0.54-0.82]; Sp 0.85 [95% CI 0.78-0.90]; LR + 4.7 [95% CI 3.3-6.7]; LR- 0.4 [95% CI 0.2-0.6]) and 4 studies for STE and revascularization (Sn 0.53 [95% CI 0.47-0.58]; Sp 0.86 [95% CI 0.80-0.91]; LR + 3.9 [95% CI 2.8-5.5]; LR- 0.5 [95% CI 0.5-0.6]). Overall certainty of evidence was low with substantial heterogeneity.

CONCLUSIONS

Based on low certainty evidence, STE had good classification for acute coronary lesion and fair classification for revascularization. STE was more specific than sensitive for these outcomes and no single ECG feature excluded them. Uniform definitions and terminology would greatly facilitate the interpretation of subsequent studies.

Post-resuscitation myocardial dysfunction in out-of-hospital cardiac arrest patients randomized to immediate coronary angiography versus standard of care

Background

Immediate coronary angiography with subsequent percutaneous coronary intervention (PCI) has the potential to reduce post-resuscitation myocardial dysfunction in out-of-hospital cardiac arrest (OHCA) patients. The aim of this study was to see if immediate coronary angiography, with potential PCI, in patients without ST-elevation on the ECG, influenced post-resuscitation myocardial function and cardiac biomarkers.

Methods

A secondary analysis of the Direct or Subacute Coronary Angiography in Out-of-Hospital Cardiac Arrest (DISCO) trial (ClinicalTrials.gov ID: NCT02309151). Patients with bystander-witnessed OHCA, without ST-elevations on the ECG were randomly assigned to immediate coronary angiography within two hours of cardiac arrest (n = 38) versus standard-of-care with deferred angiography (n = 40). Outcome measures included left ventricle ejection fraction (LVEF) at 24 h, peak Troponin T levels, lactate clearance and NT-proBNP at 72 h.

Results

In the immediate-angiography group, median LVEF at 24 h was 47% (Q1-Q3; 30–55) vs. 46% (Q1-Q3; 35–55) in the standard-of-care group. Peak Troponin-T levels during the first 24 h were 362 ng/L (Q1-Q3; 174–2020) in the immediate angiography group and 377 ng/L (Q1-Q3; 205–1078) in the standard-of-care group. NT-proBNP levels at 72 h were 931 ng/L (Q1-Q3; 396–2845) in the immediate-angiography group and 1913 ng/L (Q1-Q3; 489–3140) in the standard-of-care group.

Conclusion

In this analysis of OHCA patients without ST-elevation on the ECG randomized to immediate coronary angiography or standard-of-care, no differences in post-resuscitation myocardial dysfunction parameters between the two groups were found. This finding was consistent also in patients randomized to immediate coronary angiography where PCI was performed compared to those where PCI was not performed.

Efficacy of serum blood urea nitrogen, creatinine and electrolytes in the diagnosis and mortality risk assessment of patients with acute coronary syndrome

BACKGROUND

Although blood urea nitrogen (BUN), creatinine (Cr) and electrolytes are not the mainstay of diagnosis in acute coronary syndrome (ACS) patients but they may have a role in providing a more detailed view of the complications and mortality rates. The aim of this study was to determine the efficacy of these parameters in the diagnosis and mortality risk-assessment of patients with ACS.

METHODOLOGY

A total of 200 patients with ACS were recruited in this prospective study. The relationship of serum BUN, Cr and electrolytes with cardiac enzymes, Global Registry of Acute Coronary Events (GRACE) and mortality was assessed during a 6-months follow-up. Statistical test like multivariate linear regression and binary logistic regression analysis were applied.

RESULTS

On multivariate linear regression analysis, serum potassium (K) (Unstandardized Coefficient B=-3.77; p=0.04) showed significant negative association with Creatine Kinease and serum BUN (Unstandardized Coefficient B=0.52; p=0.001) showed significant positive association with Troponin I. The patients with GRACE>105 had significantly higher levels of serum BUN and Cr. Receiver operating characteristic curves showed that area under curve (AUC) of BUN (0.7) was higher than AUC of Cr (0.5). Multiple adjusted model showed that patients with BUN>32.5mg/dl were almost 20 times more likely to be associated with mortality as compared to reference group.

CONCLUSION

In addition to cardiac enzymes, K along with BUN and Cr may serve as important aid in diagnosis of ACS. BUN and Cr may also serve as important tools in mortality-risk assessment of ACS patients.