Chronic Myocardial Injury and Risk for Stroke

Utility of cardiovascular magnetic resonance in patients with stable troponin elevation

AIMS

Cardiovascular magnetic resonance (CMR) imaging has a potential role in the evaluation of symptomatic patients with stable troponin elevation; however, its utility remains unexplored. We sought to determine the incremental diagnostic value of CMR in this unique cohort and assess the long-term clinical outcomes.

METHODS AND RESULTS

Two hundred twenty-five consecutive patients presenting with cardiac chest pain/dyspnoea, stable troponin elevation, and undergoing CMR assessment were identified retrospectively from registry database. The study cohort was prospectively followed for major adverse cardiac events (MACEs) (defined as composite of all-cause mortality and cardiovascular readmissions). The primary outcome measure was the diagnostic utility of CMR, i.e. percentage of patients for whom CMR identified the cause of stable troponin elevation. Secondary outcome measures included the incremental value of CMR and occurrence of MACE. CMR was able to identify the cause for stable troponin elevation in 160 (71%) patients. A normal CMR was identified in 17% and an inconclusive CMR in 12% of the patients. CMR changed the referral diagnosis in 59 (26%) patients. Utilizing a baseline prediction model (pre-CMR referral diagnosis), the net reclassification index was 0.11 and integrated discriminatory improvement index measured 0.33 following CMR. Over a median follow-up of 4.3 years (interquartile range 2.8-6.3), 72 (32%) patients experienced MACE.

CONCLUSION

CMR identified a cause for stable troponin elevation in 7 of 10 cases, and a new diagnosis was evident in 1 of 4 cases. CMR improved the net reclassification of patients with stable troponin elevation.

Elevation Mechanisms and Diagnostic Consideration of Cardiac Troponins under Conditions Not Associated with Myocardial Infarction. Part 2

This article proceeds with a discussion of the causes and mechanisms of an elevation in cardiac troponins in pathological conditions not associated with acute myocardial infarction. The second part of the article discusses the causes and mechanisms of cardiac troponins elevation in diabetes mellitus, arterial hypertension, hereditary cardiomyopathies, cardiac arrhythmias (atrial fibrillation, supraventricular tachycardia), acute aortic dissection, and diseases of the central nervous system (strokes, subarachnoidal hemorrhage). The final chapter of this article discusses in detail the false-positive causes and mechanisms of elevated cardiac troponins.

Predictors associated with increased troponin in acute decompensated and chronic heart failure patients

Background: Myocardial injury (INJ) expressed by elevated high-sensitivity troponin (hs-Tn) is common in heart failure (HF), due to cardiovascular and non-cardiac conditions. The mechanisms of INJ in acute decompensated HF (ADHF) versus chronic HF (CHF) are still debated. This study’s purpose was to evaluate the determinants of elevated hs-TnT in ADHF and CHF.

Methods: We retrospectively analyzed consecutive HF patients with hs-TnT measured on admission, hospitalized in a tertiary-care hospital. Rehospitalizations, acute coronary syndromes, embolisms, infections, autoimmunity and malignancy were excluded. Cut-off point for hs-TnT was 14 ng/L.

Results: Our study included 488 HF patients, 56.55% with ADHF. Mean age was 72.52±10.09 years. 53.89% were females. 67.75% ADHF and 45.75% CHF patients had elevated hs-TnT. Median hs-TnT was higher in ADHF versus CHF (21.05[IQR 12.74-33.81] vs 13.20[IQR 7.93-23.25], p<0.0001). In multivariable analysis in ADHF and CHF, log10NT-proBNP (HR=5.30, 95%CI 2.71–10.38, p<0.001, respectively HR=5.49, 95%CI 1.71–17.57, p=0.004) and eGFR (HR=0.72, 95%CI 0.62–0.85, p<0.001, respectively HR=0.71, 95%CI 0.55–0.93, p=0.014) were independent predictors for increased hs-TnT. Independent factors associated with elevated hs-TnT in ADHF were male sex (HR=2.52, 95%CI 1.31-4.87, p=0.006) and chronic pulmonary obstructive disease (COPD) (HR=10.57, 95%CI 1.26-88.40, p=0.029), while in CHF were age (HR=2.68, 95%CI 1.42-5.07, p=0.002) and previous stroke (HR=5.35, 95%CI 0.98-29.20, p=0.053).

Conclusion: HF severity, expressed by NT-proBNP levels, and kidney disease progression, expressed by eGFR, were independent predictors associated with increased hs-TnT in both ADHF and CHF. Specific independent predictors were also indentified in ADHF (male sex, COPD) and CHF (age, history of stroke).

Healthcare and Resource Use in Patients With Stable High-Sensitivity Cardiac Troponin T Levels

Patients with elevated but stable levels of high-sensitivity cardiac troponin (hs-cTn) have a high risk of premature death and cardiovascular events. This study aimed to investigate the association between stable hs-cTnT levels and healthcare and resource use in patients with chest pain in the emergency department (ED). We included all patients who presented with chest pain and stable hs-cTnT levels without any concurrent acute medical condition at Karolinska University Hospital, Stockholm, Sweden, from 2011 to 2014. A negative binomial regression model was used to calculate incidence rates and incidence rate ratios with 95% confidence intervals (CIs) for the number of hospital visits, hospital days, and investigations performed during follow-up, in different categories of hs-cTnT levels (reference: hs-cTnT <5 ng/l). A total of 19,437 patients were included. During a follow-up of 4.1 years, 36,617 hospital visits and 206,808 hospital days were observed. Yearly rates of hospital visits and days gradually rose with increasing hs-cTnT levels from 0.3 and 1.27 (<5 ng/l) to 1.7 and 13 (≥50 ng/l) per person. In patients with hs-cTnT levels >14 ng/l, adjusted risks of in-hospital days were more than doubled (adjusted incidence rate ratio (95% CI) 2.31 (2.14 to 2.50), 2.88 (2.55 to 3.26), and 2.89 (2.45 to 3.40) in patients with hs-cTnT levels of 15 to 29, 30 to 49, and ≥50 ng/l, respectively) compared with the reference. Computed tomography, but not coronary angiography, increased with increasing hs-cTnT levels. In conclusion, stable hs-cTnT levels are associated with a higher rate of hospitalization, length of hospital stay, and resource use in patients with chest pain.

Neurological Manifestations in Critically Ill Patients With COVID-19: A Retrospective Study

Background: The complications of coronavirus disease 2019 (COVID-19) involved multiple organs or systems, especially in critically ill patients. We aim to investigate the neurological complications in critically ill patients with COVID-19. Methods: This retrospective single-center case series analyzed critically ill patients with COVID-19 at the intensive care unit of Tongji Hospital, Wuhan, China from February 5 to April 2, 2020. Demographic data, clinical and laboratory findings, comorbidities and treatments were collected and analyzed. Results: Among 86 patients with confirmed COVID-19, 54 patients (62.8%) were male, and the mean (SD) age was 66.6 (11.1) years. Overall, 65% patients presented with at least one neurological symptom. Twenty patients (23.3%) had symptoms involving the central nervous system, including delirium, cerebrovascular diseases and hypoxic-ischemic brain injury, while 6 patients (7%) had neuromuscular involvement. Seven of 86 patients exhibited new stroke and 6 (7%) cases were ischemic. A significantly higher prevalence of antiphospholipid antibodies was observed in patients with ischemic stroke than in those without stroke (83.3 vs. 26.9%, p < 0.05). Patients with ischemic stroke were more likely to have a higher myoglobulin level, and a lower hemoglobin level. Conclusions: The clinical spectrum of neurological complications in critically ill patients with COVID-19 was broad. Stroke, delirium and neuromuscular diseases are common neurological complications of COVID-19. Physicians should pay close attention to neurological complications in critically ill patients with COVID-19.

Non-coronarogenic causes of increased cardiac troponins in clinical practice

Cardiospecific isoforms of troponins are the most sensitive and specific biomarkers for the diagnosis of myocardial infarction. However, though elevated troponin levels indicate myocardial damage, they do not determine the cause and mechanism of the damage. With the new highly sensitive methods, very minor damages of the heart muscle can be detected. Myocardial damage can occur in many non-coronarogenic diseases. In this review, we discuss the mechanisms of elevation, the diagnostic value of cardiac troponins in the renal failure, tachyarrhythmias, endocarditis, myocarditis, pericarditis, sepsis, neurogenic pathologies (stroke), pulmonary embolism. In addition, we pay attention to the main reasons for a false-positive increase of the concentration of cardiac troponins: heterophilic antibodies, rheumatoid factor, alkaline phosphatase, cross-reactions with skeletal muscle troponins.

Association Between High-Sensitivity Cardiac Troponin and Risk of Stroke in 96 702 Individuals: A Meta-Analysis

Background and Purpose- Our study aim was to estimate risk of incident stroke based on levels of hs-cTn (high-sensitivity cardiac troponin), a specific biomarker indicating myocardial injury, in the general population, patients with atrial fibrillation, and patients with previous stroke. Methods- Embase, PubMed, and Web of Science were searched until March 14, 2019 to identify relevant articles. Randomized controlled trials and cohort studies assessing the risk of incident stroke based on hs-cTn were eligible. Pooled adjusted hazard ratios including 95% CI were calculated using a random-effects model due to study heterogeneity per population, coding of hs-cTn (categorical/continuous data), per hs-cTn subunit (T or I), for low risk of bias, and for all-cause and ischemic stroke separately. Results- We included 17 articles with 96 702 participants. In studies conducted in the general population (n=12; 77 780 participants), the pooled adjusted hazard ratio for incident stroke was 1.25 (CI, 1.10-1.40) for high versus low hs-cTn (as defined by included studies) during an average follow-up of 1 to 20 years (median 10). When categorical data were used, this was increased to 1.58 (CI, 1.26-1.90). The results were robust when accounting for stroke classification (all-cause stroke/ischemic stroke), hs-cTn subunit, risk of bias, and coding of hs-cTn. In patients with atrial fibrillation (4 studies; 18 725 participants), the pooled adjusted hazard ratio for incident stroke was 1.95 (CI, 1.29-2.62) for high versus low hs-cTn. Due to lack of data (one study, 197 participants), no meta-analysis could be performed in patients with previous stroke. Conclusions- This meta-analysis suggests that hs-cTn can be regarded as a risk marker for incident stroke, with different effect size in different subgroups. More research about the association between hs-cTn and incident stroke in high-risk populations is needed, especially in patients with history of ischemic stroke.