Cross-sectional study of high-sensitivity cardiac troponins T and I in a hospital and community outpatient setting

Higher troponin T serum concentrations in hospital patients without diagnosed cardiac diseases compared to a population-based cohort

OBJECTIVES

Upper reference limits of high-sensitivity cardiac troponin T (hs-cTnT) are derived from healthy, population-based cohorts, and are frequently exceeded in hospitalized patients. In this study we aim to systematically examine the differences between in-hospital patients with no diagnosed cardiac diseases and a population-based cohort.

METHODS

Retrospective analyses were performed in two independent cohorts. We included 5,652 participants of the prospective population-based LIFE cohort as well as 9,300 patients having been treated at our hospital between 2014 and 2021. In both cohorts, subjects with diagnosed or suspected cardiac diseases were excluded. We used Spearman's rank correlation for correlation analyses of hs-cTnT serum concentrations and age. Sex- and age-adjusted 99th percentiles for hs-cTnT in subjects with preserved renal function were obtained in both cohorts.

RESULTS

In both cohorts, hs-cTnT serum concentrations positively correlated with age. Male sex was associated with higher hs-cTnT serum concentrations. Persons treated in hospital showed significantly higher hs-cTnT concentrations in females and males aged above 50. While in the population-based cohort only 99th percentile hs-cTnT results of females aged above 70 and males aged above 60 years exceeded the assay's upper reference limit, the 99th percentiles of in-hospital females over 40 years and males of all age groups exceeded this threshold.

CONCLUSIONS

Besides age and sex, hospitalization per se is correlated with higher serum concentrations of hs-cTnT in most age groups. Our results indicate, that unconditionally applying current hs-cTnT cut-offs to inpatients might overestimate myocardial infarction and potentially lead to overdiagnosis.

Risk factors for myocardial injury and death in patients with COVID-19: insights from a cohort study with chest computed tomography

AIMS

Whether pulmonary artery (PA) dimension and coronary artery calcium (CAC) score, as assessed by chest computed tomography (CT), are associated with myocardial injury in patients with coronavirus disease 2019 (COVID-19) is not known. The aim of this study was to explore the risk factors for myocardial injury and death and to investigate whether myocardial injury has an independent association with all-cause mortality in patients with COVID-19.

METHODS AND RESULTS

This is a single-centre cohort study including consecutive patients with laboratory-confirmed COVID-19 undergoing chest CT on admission. Myocardial injury was defined as high-sensitivity troponin I >20 ng/L on admission. A total of 332 patients with a median follow-up of 12 days were included. There were 68 (20.5%) deaths; 123 (37%) patients had myocardial injury. PA diameter was higher in patients with myocardial injury compared with patients without myocardial injury [29.0 (25th-75th percentile, 27-32) mm vs. 27.7 (25-30) mm, P < 0.001). PA diameter was independently associated with an increased risk of myocardial injury [adjusted odds ratio 1.10, 95% confidence interval (CI) 1.02-1.19, P = 0.01] and death [adjusted hazard ratio (HR) 1.09, 95% CI 1.02-1.17, P = 0.01]. Compared with patients without myocardial injury, patients with myocardial injury had a lower prevalence of a CAC score of zero (25% vs. 55%, P < 0.001); however, the CAC score did not emerge as a predictor of myocardial injury by multivariable logistic regression. Myocardial injury was independently associated with an increased risk of death by multivariable Cox regression (adjusted HR 2.25, 95% CI 1.27-3.96, P = 0.005). Older age, lower estimated glomerular filtration rate, and lower PaO2/FiO2 ratio on admission were other independent predictors for both myocardial injury and death.

CONCLUSIONS

An increased PA diameter, as assessed by chest CT, is an independent risk factor for myocardial injury and mortality in patients with COVID-19. Myocardial injury is independently associated with an approximately two-fold increased risk of death.

Clinical outcomes for chest pain patients discharged home from emergency departments using high-sensitivity versus conventional cardiac troponin assays

BACKGROUND

High-sensitivity cardiac troponin (hs-cTn) assays enhance detection of lower circulating troponin concentrations, but the impact on outcomes in clinical practice is unclear. Our objective was to compare outcomes of chest pain patients discharged from emergency departments (EDs) using hs-cTn and conventional troponin (cTn) assays.

METHODS

We conducted an observational study of chest pain patients aged 40-105 years who presented to an ED from April 1, 2013, to March 31, 2017, and were discharged home. We compared 30-day and 1-year outcomes of EDs that used hs-cTn versus cTn assays. The primary outcome was a composite of all-cause death, myocardial infarction or unstable angina. Comparisons were conducted with (1) no adjustment; (2) adjustment for demographic, socioeconomic, and hospital characteristics; and (3) full clinical adjustment.

RESULTS

Among the 394,910 patients, 62,138 (15.7%) were evaluated at hs-cTn EDs and 332,772 (84.3%) were evaluated at cTn EDs. Patients discharged from hs-cTn EDs were less likely to have diabetes, hypertension, or prior heart disease. At 30 days, the unadjusted primary outcome rate was lower in hs-cTn EDs (0.9% vs 1.0%, P < .001). The 30-day hazard ratios for the primary outcome were 0.84 (95% CI 0.77-0.92) for no adjustment and 0.98 (95% CI 0.88-1.08) for full adjustment. Over 1 year, patients discharged from hs-cTn EDs had significantly fewer primary outcomes (3.7% vs 4.1%, P < .001) and lower hazard ratio (0.93; 95% CI 0.89-0.98) even after full adjustment.

CONCLUSIONS

Hs-cTn testing was associated with a significantly lower adjusted hazard of myocardial infarction, angina, and all-cause hospitalization at 1 year but not 30 days.

Perioperative myocardial injury in revascularized coronary patients who undergo noncardiac surgery

BACKGROUND

Whether high-sensitivity cardiac troponin elevation during the perioperative period is associated with poor clinical outcome in revascularized coronary patients who undergo noncardiac surgery remains unclear. We investigated the effects of perioperative troponin elevation on the long-term clinical outcomes of patients with a history of coronary revascularization.

METHODS

We analyzed patients whose pre- or postoperative high-sensitivity cardiac troponin I (hs-cTnI) assay results were available. Patients were divided into two groups according to hs-cTnI levels. The patient groups were analyzed separately according to whether hs-cTnI was assessed preoperatively or postoperatively. The primary outcome was all-cause death during the follow-up period.

RESULTS

Median follow-up duration was 25 months (interquartile range 11-50). In the propensity-matched analysis, the risk of all-cause death during follow-up was higher in the group with elevated hs-cTnI group than in the normal group (12.7% vs 6.3%; hazard ratio [HR], 2.67; 95% confidential interval [CI], 1.04-6.82; p = 0.04). In the propensity-matched analysis of preoperative hs-cTnI levels, we found no significant difference between the groups in the rate of all-cause death (12.9% vs. 11.9%; HR, 1.06; 95% CI, 0.45-2.50; p = 0.89). In the postoperative propensity-matched analysis, all-cause death was higher in patients with elevated hs-cTnI than in those with normal levels (14.9% vs. 5.9%; HR, 2.80; 95% CI, 1.01-7.77; p = 0.048).

CONCLUSION

In revascularized coronary patients who underwent noncardiac surgery, postoperative (but not preoperative) hs-cTnI elevation was associated with all-cause death during follow-up. Larger datasets are needed to support this finding.

Novel Risk Stratification Assays for Acute Coronary Syndrome

PURPOSE OF REVIEW

Since identification of aspartate aminotransferase as the first cardiac biomarker in the 1950s, there have been a number of new markers used for myocardial damage detection over the decades. There have also been several generations of troponin assays, each with progressively increasing sensitivity for troponin detection. Accordingly, the "standard of care" for myocardial damage detection continues to change. The purpose of this paper is to review the clinical utility, biological mechanisms, and predictive value of these various biomarkers in contemporary clinical studies.

RECENT FINDINGS

As of this writing, a fifth "next" generation troponin assay has now been cleared by the US Food and Drug Administration for clinical use in the USA for subjects presenting with suspected acute coronary syndromes. Use of these high-sensitivity assays has allowed for earlier detection of myocardial damage as well as greater negative predictive value for infarction after only one or two serial measurements. Recent algorithms utilizing these assays have allowed for more rapid rule-out of myocardial infarction in emergency department settings. In this review, we discuss novel assays available for the risk assessment of subjects presenting with chest pain, including both the "next generation" cardiac troponin assays as well as other novel biomarkers. We review the biological mechanisms for these markers, and explore the positive and negative predictive value of the assays in clinical studies, where reported. We also discuss the potential use of these new markers within the context of future clinical care in the modern era of higher sensitivity troponin testing. Finally, we discuss advances in new platforms (e.g., mass spectrometry) that historically have not been considered for rapid in vitro diagnostic capabilities, but that are taking a larger role in clinical diagnostics, and whose prognostic value and power promise to usher in new markers with potential for future clinical utility in acute coronary syndrome.

The relationship of plasma creatinine (as eGFR) and high-sensitivity cardiac troponin and NT-proBNP concentrations in a hospital and community outpatient population

OBJECTIVES

While persons with overt renal failure have a well-described rise in troponin and NT-proBNP, it is less well described what the relationship is between cardiac markers and persons with impaired renal function, not requiring dialysis.

DESIGN & METHODS

We have collected ALL samples referred to our pathology practice over a 24h period and measured hs-cTnI, hs-cTnT, NT-proBNP, calculated the eGFR, and related our measurements to clinical outcomes.

RESULTS

For both men and women, for all of hs-cTnI, hs-cTnT and NT-proBNP, there was a graded response, as renal function worsened, the concentration of the cardiac marker increased.

CONCLUSIONS

There is a graded inverse relationship between eGFR and the concentrations of hs-cTnI, hs-cTnT and NT-proBNP. For women only there appeared to be an increase in mortality at lowest eGFR.