Association of High-Sensitivity Troponin with Cardiac CT Angiography Evidence of Myocardial and Coronary Disease in a Primary Prevention Cohort of Men: Results from MACS

Prognostic Value of High-Sensitivity Cardiac Troponin in Women

High-sensitivity cardiac troponin assays have become the gold standard for diagnosing acute and chronic myocardial injury. The detection of troponin levels beyond the 99th percentile is included in the fourth universal definition of myocardial infarction, specifically recommending the use of sex-specific thresholds. Measurable concentrations below the proposed diagnostic thresholds have been shown to inform prognosis in different categories of inpatients and outpatients. However, clinical investigations from the last twenty years have yielded conflicting results regarding the incremental value of using different cut-offs for men and women. While advocates of a sex-specific approach claim it may help reduce gender bias in cardiovascular medicine, particularly in acute coronary syndromes, other groups question the alleged incremental diagnostic and prognostic value of sex-specific thresholds, ultimately asserting that less is more. In the present review, we aimed to synthesize our current understanding of sex-based differences in cardiac troponin levels and to reappraise the available evidence with regard to (i) the prognostic significance of sex-specific diagnostic thresholds of high-sensitivity cardiac troponin assays compared to common cut-offs in both men and women undergoing cardiovascular disease risk assessment, and (ii) the clinical utility of high-sensitivity cardiac troponin assays for cardiovascular disease prevention in women.

Cardiovascular risk factors and markers of myocardial injury and inflammation in people living with HIV in Nairobi, Kenya: a pilot cross-sectional study

OBJECTIVES

To determine the prevalence of cardiovascular disease (CVD) risk factors and explore associations with high-sensitivity cardiac troponin I (hscTnI) and high-sensitivity C-reactive protein (hsCRP) in people living with HIV (PLHIV) in Kenya.

DESIGN

Pilot cross-sectional study.

SETTING

Data were collected from community HIV clinics across two sites in Nairobi, Kenya, from July 2019 to May 2020.

PARTICIPANTS

Convenience sample of 200 PLHIV (≥30 years with no prior history of CVD).

OUTCOME MEASURES

Prevalence of cardiovascular risk factors and its association with hsTnI and hsCRP levels.

RESULTS

Across 200 PLHIV (median age 46 years, IQR 38-53; 61% women), the prevalence of hypercholesterolaemia (total cholesterol >6.1 mmol/L) and hypertension were 19% (n=30/199) and 30% (n=60/200), respectively. Smoking and diabetes prevalence was 3% (n=5/200) and 4% (n=7/200). HscTnI was below the limit of quantification (<2.5 ng/L) in 65% (n=109/169). High (>3 mg/L), intermediate (1-3 mg/L) and low (<1 mg/L) hsCRP levels were found in 38% (n=75/198), 33% (n=65/198) and 29% (n=58/198), respectively. Framingham laboratory-based risk scores classified 83% of PLHIV at low risk with 12% and 5% at intermediate and high risk, respectively. Older age (adjusted OR (aOR) per year increase 1.05, 95% CI 1.01 to 1.08) and systolic blood pressure (140-159 mm Hg (aOR 2.96; 95% CI 1.09 to 7.90) and >160 mm Hg (aOR 4.68, 95% CI 1.55 to 14) compared with <140 mm Hg) were associated with hscTnI levels. No associations were observed between hsCRP and CVD risk factors.

CONCLUSION

The majority of PLHIV-using traditional risk estimation systems-have a low estimated CVD risk likely reflecting a younger aged population predominantly consisting of women. Hypertension and hypercholesterolaemia were common while smoking and diabetes rates remained low. While hscTnI values were associated with increasing age and raised blood pressure, no associations between hsCRP levels and traditional cardiovascular risk factors were observed.

Associations of High-Sensitivity Troponin and Natriuretic Peptide Levels With Outcomes After Intensive Blood Pressure Lowering: Findings From the SPRINT Randomized Clinical Trial

Importance

Elevated high-sensitivity cardiac troponin T (hscTnT) and N-terminal pro-B-type natriuretic peptide (NTproBNP) levels are associated with risk of heart failure (HF) and mortality among individuals in the general population. However, it is unknown if this risk is modifiable.

Objective

To test the hypothesis that elevated hscTnT and NTproBNP levels would identify individuals with the greatest risk for mortality and HF and the largest benefit associated with intensive systolic blood pressure (SBP) lowering.

Design, Setting, and Participants

This is a nonprespecified post hoc analysis of the multicenter, prospective, randomized clinical Systolic Blood Pressure Intervention Trial (SPRINT), conducted from October 20, 2010, to August 20, 2015. A total of 9361 patients without diabetes with increased risk for cardiovascular disease were randomized to receive intensive vs standard SBP lowering. Statistical analysis was performed on an intention-to-treat basis from September 30, 2019, to July 29, 2021.

Interventions

Participants were randomized to undergo intensive (<120 mm Hg) or standard (<140 mm Hg) SBP lowering. High-sensitivity cardiac troponin T and NTproBNP levels were measured from stored specimens collected at enrollment, with elevated levels defined as 14 ng/L or more for hscTnT (to convert to micrograms per liter, multiply by 0.001) and 125 pg/mL or more for NTproBNP (to convert to nanograms per liter, multiply by 1.0).

Main Outcomes and Measures

The primary outcome of this ancillary study was HF and mortality.

Results

Of the 9361 participants enrolled in SPRINT, 8828 (5578 men [63.2%]; mean [SD] age, 68.0 [9.5] years) had measured hscTnT levels and 8836 (5585 men [63.2%]; mean [SD] age, 68.0 [9.5] years) had measured NTproBNP levels; 2262 of 8828 patients (25.6%) had elevated hscTnT levels, 3371 of 8836 patients (38.2%) had elevated NTproBNP, and 1411 of 8828 patients (16.0%) had both levels elevated. Randomization to the intensive SBP group led to a 4.9% (95% CI, 1.7%-7.5%) absolute risk reduction (ARR) over 4 years in death and HF (421 events) for those with elevated hscTnT and a 1.7% (95% CI, 0.7%-2.5%) ARR for those without elevated levels. Similarly, for those with elevated NTproBNP, the ARR for death and HF over 4 years was 4.6% (95% CI, 2.3%-6.5%) vs 1.8% (95% CI, 0.9%-2.5%) in those without elevated levels. For those with elevated levels of both biomarkers, the ARR for death and HF over 4 years was 7.8% (95% CI, 3.3%-11.3%) vs 1.7% (95% CI, 0.8%-2.3%) in those with neither biomarker elevated. No significant treatment group by biomarker category interactions were detected.

Conclusions and Relevance

Intensive SBP control led to large absolute differences in death and HF among patients with abnormal hscTnT and NTproBNP levels. These findings demonstrate that risk associated with elevation of these biomarkers is modifiable with intensive BP control. A prospective, randomized clinical trial is needed to evaluate whether these biomarkers may help guide selection of patients for intensive SBP lowering.

Trial Registration

ClinicalTrials.gov Identifier: NCT01206062.

A Test in Context: Interpretation of High-Sensitivity Cardiac Troponin Assays in Different Clinical Settings

High-sensitivity cardiac troponin (hs-cTn) assays have the ability to detect minute troponin concentrations and resolve minor changes in biomarker concentrations. Clinically, this allows for the ability to rapidly identify or exclude acute myocardial injury in the setting of acute chest discomfort-thus providing more rapid evaluation for acute myocardial infarction-but the improvements in troponin assays also create avenues for other applications where troponin release from the cardiomyocyte might confer prognostic information. These situations include cardiovascular risk assessment across a wide range of clinical circumstances, including apparently-well individuals, those at risk for heart disease, and those with prevalent cardiovascular disorders. The optimal hs-cTn threshold for each circumstance varies by the assay used and by the population assessed. This review will provide context for how hs-cTn assays might be interpreted depending on the application sought, reviewing results from studies leveraging hs-cTn for applications beyond "acute myocardial infarction diagnostic evaluation."