Cardiovascular Biomarkers and Imaging in Older Adults: JACC Council Perspectives

Cardiovascular Aging and Risk Assessment: How Multimodality Imaging Can Help

Aging affects the cardiovascular system, and this process may be accelerated in individuals with cardiovascular risk factors. The main vascular changes include arterial wall thickening, calcification, and stiffening, together with aortic dilatation and elongation. With aging, we can observe left ventricular hypertrophy with myocardial fibrosis and left atrial dilatation. These changes may lead to heart failure and atrial fibrillation. Using multimodality imaging, including ultrasound, computed tomography (CT), and magnetic resonance imaging, it is possible to detect these changes. Additionally, multimodality imaging, mainly via CT measurements of coronary artery calcium or ultrasound carotid intima-media thickness, enables advanced cardiovascular risk stratification and helps in decision-making about preventive strategies. The focus of this manuscript is to briefly review cardiovascular changes that occur with aging, as well as to describe how multimodality imaging may be used for the assessment of these changes and risk stratification of asymptomatic individuals.

Management of Acute Coronary Syndromes in Older People: Comprehensive Review and Multidisciplinary Practice-Based Recommendations

Managing health care for older adults aged 75 years and older can pose unique challenges stemming from age-related physiological differences and comorbidities, along with elevated risk of delirium, frailty, disability, and polypharmacy. This review is aimed at providing a comprehensive analysis of the management of acute coronary syndromes (ACS) in older patients, a demographic substantially underrepresented in major clinical trials. Because older patients often exhibit atypical ACS symptoms, a nuanced diagnostic and risk stratification approach is necessary. We aim to address diagnostic challenges for older populations and highlight the diminished sensitivity of traditional symptoms with age, and the importance of biomarkers and imaging techniques tailored for older patients. Additionally, we review the efficacy and safety of pharmacological agents for ACS management in older people, emphasizing the need for a personalized and shared decision-making approach to treatment. This review also explores revascularization strategies, considering the implications of invasive procedures in older people, and weighing the potential benefits against the heightened procedural risks, particularly with surgical revascularization techniques. We explore the perioperative management of older patients experiencing myocardial infarction in the setting of noncardiac surgeries, including preoperative risk stratification and postoperative care considerations. Furthermore, we highlight the critical role of a multidisciplinary approach involving cardiologists, geriatricians, general and internal medicine physicians, primary care physicians, and allied health, to ensure a holistic care pathway in this patient cohort.

Elevated Troponins and Diagnosis of Non-ST-Elevation Myocardial Infarction in the Emergency Department

Background In the emergency department (ED), the diagnosis of non-ST-elevation myocardial infarction (NSTEMI) is primarily based on the presence or absence of elevated cardiac troponin levels, ECG changes, and clinical presentation. However, limited data exist regarding the incidence, clinical characteristics, and predictive value of different cardiac diagnostic tests and outcomes in patients with non-acute coronary syndrome (ACS)-related troponin elevation. Our study aimed to determine the percentage of patients with elevated troponin levels who had true ACS and identify various risk factors associated with true ACS in these patients. Methodology This was a single-center retrospective study. We performed a chart review of patients who presented to the ED from January 1, 2016, to December 31, 2017, and were admitted to the hospital with an elevated cardiac troponin I level in the first 12 hours after ED presentation with a diagnosis of NSTEMI. True ACS was defined as (a) patients with typical symptoms of ischemia and ECG ischemic changes and (b) patients with atypical symptoms of myocardial ischemia or without symptoms of ischemia and new segmental wall motion abnormalities on echocardiogram or evidence of culprit lesion on angiography. A logistic regression model was used to determine the association between risk factors and true ACS. Results A total of 204 patients were included in this study. The mean age of the study group was 67.4 ± 14.5 years; 53.4% (n = 109) were male, and 57.4% (n = 117) were Caucasian. In our study, 51% of patients were found to have true ACS, and the remaining 49% had a non-ACS-related elevation in troponins. Most patients without ACS had alternate explanations for elevated troponin levels. The presence of chest pain (odds ratio (OR) = 3.7, 95% confidence interval (CI) = 1.8-7.7, p = 0.001), tobacco smoking (OR = 4, 95% CI = 1.06-3.8, p = 0.032), and wall motion abnormalities on echocardiogram (OR = 3.8, 95% CI = 1.8-6.5, p = 001) were associated with increased risk of true ACS in patients with elevated troponins. Conclusions Cardiac troponin levels can be elevated in hospitalized patients with various medical conditions, in the absence of ACS. The diagnosis of ACS should not be solely based on elevated troponin levels, as it can lead to expensive workup and utilization of hospital resources.

Systematic Review of Literature Citing the ISCHEMIA Trial

PURPOSE OF REVIEW

Optimal therapy for patients with chronic coronary artery disease (CCD) has long been a topic under investigation and a subject of debate. Seeking to clarify appropriate management, the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial compared medical management versus coronary angiography for patients with stable ischemic heart disease. Its reception in the medical community has been met with both acclaim and criticism. In light of such disparate views of this trial, a systematic review of the literature citing the ISCHEMIA trial was performed.

RECENT FINDINGS

All articles citing the ISCHEMIA trial on PubMed as of July 21, 2023, were compiled and underwent qualitative analysis. A total of 430 articles were evaluated; 109 (25.3%) did not offer substantial commentary on ISCHEMIA and cite it as background evidence for further study. Of the commentary articles, the majority (224, 52.1%) gave balanced, honest appraisals of the ISCHEMIA trial. A total of 46 (10.7%) strongly praised the trial while another 39 (9.1%) were strongly critical of the results. Almost three-quarters of the literature citing the ISCHEMIA trial was commentary in nature, with roughly equal distribution across the spectrum of praise and criticism. Despite being one of the largest studies on CCD and coronary revascularization ever conducted, the impact of ISCHEMIA on the cardiology community appears to be mixed.

Role of NT-proBNP and lung ultrasound in diagnosing and classifying heart failure in a hospitalized oldest-old population: a cross-sectional study

AIM

Diagnosing and classifying heart failure (HF) in the oldest-old patients has technical and interpretation issues, especially in the acute setting. We assessed the usefulness of both N-terminal pro-brain natriuretic peptide (NT-proBNP) and lung ultrasound (LUS) for confirming HF diagnosis and predicting, among hospitalized HF patients, those with reduced ejection fraction (HFrEF).

METHODS

We performed a cross-sectional study on 148 consecutive patients aged ≥ 80 years admitted to our Internal Medicine and Geriatrics ward with at least one symptom/sign compatible with HF and NT-proBNP ≥ 125 pg/mL. We measured serum NT-proBNP levels and performed LUS and transthoracic echocardiography (TTE) on admission before diuretic therapy. We divided our cohort into three subgroups according to the left ventricular ejection fraction (LVEF): reduced (LVEF ≤ 40%), mildly-reduced (LVEF = 41-49%) and preserved (LVEF ≥ 50%).

RESULTS

The mean age was 88±5 years. Male prevalence was 42%. Patients with HFrEF were 19%. Clinical features and laboratory parameters did not differ between the three subgroups, except for higher NT-proBNP in HFrEF patients, which also had a higher number of total B-lines and intercostal spaces of pleural effusion at LUS. Overall, NT-proBNP showed an inverse correlation with LVEF (r = -0.22, p = 0.007) and a direct correlation with age, total pulmonary B-lines, and intercostal spaces of pleural effusion. According to the ROCs, NT-proBNP levels, pulmonary B-lines and pleural effusion extension were poorly predictive for HFrEF. The best-performing cut-offs were 9531 pg/mL for NT-proBNP (SP 0.70, SE 0.50), 13 for total B-lines (SP 0.69, SE 0.85) and one intercostal space for pleural effusion (SP 0.55, SE 0.89). Patients with admission NT-proBNP ≥ 9531 pg/mL had a 2-fold higher risk for HFrEF (OR 2.5, 95% CI 1.3-4.9), while we did not find any association for total B-lines ≥ 13 or pleural effusion ≥ 1 intercostal space with HFrEF. A significant association with HFrEF emerged for the combination of NT-proBNP ≥ 9531 pg/mL, total B-lines ≥ 13 and intercostal spaces of pleural effusion ≥ 1 (adjusted OR 4.3, 95% CI 1.5-12.9).

CONCLUSIONS

Although NT-proBNP and LUS help diagnose HF, their accuracy in discriminating HFrEF from non-HFrEF was poor in our real-life clinical study on oldest-old hospitalized patients, making the use of TTE still necessary to distinguish HF phenotypes in this peculiar setting. These data require confirmation in more extensive and longer prospective studies.

Developing Cardiac Digital Twins at Scale: Insights from Personalised Myocardial Conduction Velocity

Large-cohort studies using cardiovascular imaging and diagnostic datasets have assessed cardiac anatomy, function, and outcomes, but typically do not reveal underlying biological mechanisms. Cardiac digital twins (CDTs) provide personalized physics- and physiology-constrained in-silico representations, enabling inference of multi-scale properties tied to these mechanisms. We constructed 3464 anatomically-accurate CDTs using cardiac magnetic resonance images from UK biobank and personalised their myocardial conduction velocities (CVs) from electrocardiograms (ECG), through an automated framework. We found well-known sex-specific differences in QRS duration were fully explained by myocardial anatomy, as CV remained consistent across sexes. Conversely, significant associations of CV with ageing and increased BMI suggest myocardial tissue remodelling. Novel associations were observed with left ventricular ejection fraction and mental-health phenotypes, through a phenome-wide association study, and CV was also linked with adverse clinical outcomes. Our study highlights the utility of population-based CDTs in assessing intersubject variability and uncovering strong links with mental health.

TCA cycle metabolites associated with adverse outcomes after acute coronary syndrome: mediating effect of renal function

Aims

To examine relationships of tricarboxylic acid (TCA) cycle metabolites with risk of cardiovascular events and mortality after acute coronary syndrome (ACS), and evaluate the mediating role of renal function in these associations.

Methods

This is a prospective study performed among 309 ACS patients who were followed for a mean of 6.7 years. During this period 131 patients developed major adverse cardiovascular events (MACE), defined as the composite of myocardial infarction, hospitalization for heart failure, and all-cause mortality, and 90 deaths were recorded. Plasma concentrations of citrate, aconitate, isocitrate, succinate, malate, fumarate, α-ketoglutarate and d/l-2-hydroxyglutarate were quantified using LC-tandem MS. Multivariable Cox regression models were used to estimate hazard ratios, and a counterfactual-based mediation analysis was performed to test the mediating role of estimated glomerular filtration rate (eGFR).

Results

After adjustment for traditional cardiovascular risk factors and medications, positive associations were found between isocitrate and MACE (HR per 1 SD, 1.25; 95% CI: 1.03, 1.50), and between aconitate, isocitrate, d/l-2-hydroxyglutarate and all-cause mortality (HR per 1 SD, 1.41; 95% CI: 1.07, 1.84; 1.58; 95% CI: 1.23, 2.02; 1.38; 95% CI: 1.14, 1.68). However, these associations were no longer significant after additional adjustment for eGFR. Mediation analyses demonstrated that eGFR is a strong mediator of these associations.

Conclusion

These findings underscore the importance of TCA metabolites and renal function as conjunctive targets in the prevention of ACS complications.

Soluble Urokinase-Type Plasminogen Activator Receptor (suPAR) Is a Biomarker Associated with Left Ventricular Hypertrophy in the Elderly, Specifically in Women

Left ventricular hypertrophy (LVH) may result in the development of heart failure, which is widespread among people of advanced age. The pathophysiology of LVH is complex and its biochemical pathways are not fully understood in this group. Elevated soluble urokinase-type plasminogen activator receptor (suPAR), a biomarker of immune activation, including fibrosis, reflects subclinical organ damage in systematic diseases. The present study assesses the clinical role of suPAR measurement in determination of LVH-associated cardiac disorders in the elderly. The studied population consisted of 238 individuals aged 76-91 years; of these, 139 (58%) were diagnosed with LVH. Serum biomarkers measurement (suPAR, troponin T, NT-proBNP and CRP) and echocardiography were performed in all subjects. The suPAR level was significantly higher in the LVH group (4.01 vs. 3.82 ng/mL, p = 0.033) and correlated with the parameters of cardiac diastolic function. Stepwise logistic regression found suPAR level (OR = 1.55, p = 0.016), BMI (OR = 1.17, p = 0.0003) and hypertension (OR = 2.42, p = 0.046) to be independently associated with LVH in women. In men, the strongest predictors of LVH were hypertension (OR = 7.52, p = 0.014) and BMI (OR = 1.42, p = 0.032). The observations indicate suPAR as a promising marker reflecting LVH, especially in women at advanced age, independent of age-associated cardiac remodeling.

How to Improve Clinical Outcomes and Reduce Cardiovascular Risk in Older People with Cardiovascular Disease: Bridging Evidence Gaps

The geriatric population is greatly impacted by cardiovascular disease. Thus, it becomes essential to 'geriatricise' the cardiologist through the dissemination of geriatric cardiology. In the early days of geriatric cardiology, it was discussed whether it was simply cardiology 'well done'. Today, 40 years later, it seems clear that this is indeed the case. Patients with cardiovascular disease usually have several chronic conditions. Clinical practice guidelines often address a single condition and do not provide sufficient guidance for patients with multimorbidity. There are several evidence gaps regarding these patients. Physicians and members ofthe care team need a multidimensional understanding ofthe patient to better promote the optimisation of care. It is important to understand that ageing is inevitable, heterogeneous and increases vulnerability. Caregivers must know how to assess elderly patients in a multidomain practical way and how to recognise the factors that may have implications on treatment.

Admission high-sensitivity cardiac troponin levels as a prognostic indicator for in-hospital mortality rates in the elderly and very elderly COVID-19 patients

BACKGROUND

Elevation of cardiac troponin (cTn) is associated with the worst prognosis not only in cardiovascular disease but also in non-cardiovascular disease. The aim of this study is to verify if cTn has a prognostic role in elderly and very elderly coronavirus disease 2019 (COVID-19) patients.

METHODS

This study enrolled consecutive COVID-19 elderly patients hospitalized at INRCA hospital, with available admission high sensitivity cardiac troponin T (HS-cTnT) level. Patients were divided into three groups based on HS-cTnT level: group A (Hs-cTnT ≤ 40 pg/ml), group B (Hs-cTnT 41-100 pg/ml), and group C (Hs-cTnT ≥ 101 pg/ml). The correlation between HS-cTnT levels and mortality rates was analyzed.

RESULTS

461 patients (mean age 86 years; 59% female) were divided into group A (261 patients), group B (129 patients), and group C (71 patients). Group C resulted significantly older, more affected by heart failure, chronic obstructive pulmonary disease, chronic kidney disease, and dementia, and with higher levels of creatinine, C-reactive protein, pro-calcitonin, interleukin-6, ferritin, NT-proBNP, D-dimer then group A and group B. Mortality rate increased significantly across groups (group A: 18.4%; group B: 36.4%; group C: 62.0%; p<0.001). Group C had a significant increase in mortality risk compared to group A, both univariate analysis (HR 3.78) and multivariate analysis (model 2 HR 3.10; model 3 HR 3.59; model 4 HR 1.72).

CONCLUSION

HS-cTnT has demonstrated a prognostic role in elderly and very elderly COVID-19 patients. HS-cTnT is a simple and inexpensive laboratory exam that gives clinicians important information on mortality risk stratification.

The Aging Heart: A Molecular and Clinical Challenge

Aging is associated with an increasing burden of morbidity, especially for cardiovascular diseases (CVDs). General cardiovascular risk factors, ischemic heart diseases, heart failure, arrhythmias, and cardiomyopathies present a significant prevalence in older people, and are characterized by peculiar clinical manifestations that have distinct features compared with the same conditions in a younger population. Remarkably, the aging heart phenotype in both healthy individuals and patients with CVD reflects modifications at the cellular level. An improvement in the knowledge of the physiological and pathological molecular mechanisms underlying cardiac aging could improve clinical management of older patients and offer new therapeutic targets.

New strategies and therapies for the prevention of heart failure in high-risk patients

Despite declines in total cardiovascular mortality rates in the United States, heart failure (HF) mortality rates as well as hospitalizations and readmissions have increased in the past decade. Increases have been relatively higher among young and middle-aged adults (<65 years). Therefore, identification of individuals HF at-risk (Stage A) or with pre-HF (Stage B) before the onset of overt clinical signs and symptoms (Stage C) is urgently needed. Multivariate risk models (e.g., Pooled Cohort Equations to Prevent Heart Failure [PCP-HF]) have been externally validated in diverse populations and endorsed by the 2022 HF Guidelines to apply a risk-based framework for the prevention of HF. However, traditional risk factors included in the PCP-HF model only account for half of an individual's lifetime risk of HF; novel risk factors (e.g., adverse pregnancy outcomes, impaired lung health, COVID-19) are emerging as important risk-enhancing factors that need to be accounted for in personalized approaches to prevention. In addition to determining the role of novel risk-enhancing factors, integration of social determinants of health (SDoH) in identifying and addressing HF risk is needed to transform the current clinical paradigm for the prevention of HF. Comprehensive strategies to prevent the progression of HF must incorporate pharmacotherapies (e.g., sodium glucose co-transporter-2 inhibitors that have also been termed the "statins" of HF prevention), intensive blood pressure lowering, and heart-healthy behaviors. Future directions include investigation of novel prediction models leveraging machine learning, integration of risk-enhancing factors and SDoH, and equitable approaches to interventions for risk-based prevention of HF.

Echocardiographic Ischemic Memory Molecular Imaging for Point-of-Care Detection of Myocardial Ischemia

BACKGROUND

Noninvasive molecular imaging of recent ischemia can potentially be used to diagnose acute coronary syndrome (ACS) with high accuracy.

OBJECTIVES

The authors hypothesized that bedside myocardial contrast echocardiography (MCE) ischemic memory imaging could be achieved with phosphatidylserine microbubbles (MB_PS) that are retained in the microcirculation via ischemia-associated endothelial activation.

METHODS

A dose-finding study was performed in healthy volunteers (n = 17) to establish optimal MB_PS dosing. Stable patients with ACS (n = 30) and confirmed antecedent but resolved myocardial ischemia were studied within 2 hours of coronary angiography and percutaneous coronary intervention (PCI) when indicated. MCE molecular imaging was performed 8 minutes after intravenous administration of MB_PS. MCE perfusion imaging was used to assess the status of the postischemic microcirculation.

RESULTS

Based on dose-finding studies, 0.10 or 0.15 mL of MB_PS based on body mass was selected. In patients with ACS, all but 2 underwent primary PCI. MCE molecular imaging signal intensity was greater in the postischemic risk area vs remote territory (median [95% CI]: 56 [33-66] vs 8 [2-17] IU; P < 0.001) with a receiver-operating characteristic curve C-statistic of 0.94 to differentiate post-ischemic from remote territory. Molecular imaging signal in the risk area was not related to type of ACS (unstable angina: 3; non-ST-segment elevation myocardial infarction: 14; ST-segment elevation myocardial infarction: 13), peak troponin, time to PCI, post-PCI myocardial perfusion, GRACE (Global Registry of Acute Coronary Events) score, or HEART score.

CONCLUSIONS

Molecular imaging with point-of-care echocardiography and MB_PS can detect recent but resolved myocardial ischemia. This bedside technique requires only minutes to perform and appears independent of the degree of ischemia. (Ischemic Memory Imaging With Myocardial Contrast Echocardiography; NCT03009266).

Aspirin and statin therapy for primary prevention of cardiovascular disease in older adults

The value of primary preventative therapies for cardiovascular disease (CVD) in older adults (age ≥75 years) is less certain than in younger patients. There is a lack of quality evidence in older adults due to underenrolment in pivotal trials. While aspirin is no longer recommended for routine use in primary prevention of CVD in older adults, statins may be efficacious. However, it is unclear which patient subgroups may benefit most, and guidelines differ between expert panels. Three relevant geriatric conditions (cognitive impairment, functional impairment and polypharmacy) may influence therapeutic decision making; for example, baseline frailty may affect statin efficacy, and some have advocated for deprescription in this scenario. Evidence regarding statins and incident functional decline are mixed, and vigilance for adverse effects is important, especially in the setting of polypharmacy. However, aspirin has not been shown to affect incident cognitive or functional decline, and its lack of efficacy extends to patients with baseline cognitive impairment or frailty. Ultimately, the utility of primary preventative therapies for CVD in older adults depends on potential lifetime benefit. Rather than basing treatment decisions on absolute risk alone, consideration of comorbidities, polypharmacy and life expectancy should play a significant role in decision making. Coronary calcium score and new tools for risk stratification validated in older adults that account for the competing risk of death may aid in evaluating potential benefits. Given the complexity of therapeutic decisions in this context, shared decision making provides an important framework.

Aspirin, Statins, and Primary Prevention: Opportunities for Shared Decision Making in the Face of Uncertainty

PURPOSE OF REVIEW

The utility of aspirin and statins for primary prevention of atherosclerotic cardiovascular disease remains ambiguous in older adults. Current guidelines and recent data are vague and inconclusive. This review seeks to summarize the landscape of primary prevention of cardiovascular disease in older adults and explore the role of shared decision making.

RECENT FINDINGS

Observational data suggest potential benefit of statin therapy in older adults. Aspirin is presently not recommended for primary prevention based on evidence from recent clinical trials. The implementation of shared decision making and decision aids in routine clinical practice remains challenging but may rise in coming years. Clinical trial data on the horizon may aid in solidifying guideline therapy for statin use. However, in the face of uncertainty, shared decision making between provider and patient should be utilized to determine whether pharmacotherapy may benefit older adults. Decision aids are an effective tool to guide this process.

MicroRNA-328-5p Alleviates Macrophage Lipid Accumulation through the Histone Deacetylase 3/ATP-binding cassette transporter A1 pathway

MicroRNA-328 (miR-328) was reported to protect against atherosclerosis, but its role in foam cell formation remains unknown. The aim of this study was to investigate the effect of miR-328-5p on macrophage lipid accumulation and the underlying mechanisms. The results showed that miR-328-5p expression was robustly decreased in oxidized low-density lipoprotein (ox-LDL)-treated macrophages. Treatment of human acute monocytic leukemia cel (THP-1) macrophage-derived foam cells with a miR-328-5p mimic markedly increased [³ H]-cholesterol efflux, inhibited lipid droplet accumulation, and decreased intracellular total cholesterol (TC), free cholesterol (FC) and cholesteryl ester (CE) contents. Upregulation of miR-328-5p also reduced the expression of histone deacetylase 3 (HDAC3) but increased the levels of ATP-binding cassette transporter A1 (ABCA1) in THP-1 macrophage-derived foam cells. Mechanistically, miR-328-5p inhibited HDAC3 expression by directly targeting its 3'UTR, thereby promoting ABCA1 expression and the subsequent cholesterol efflux. Furthermore, miR-328-5p mimic treatment did not affect the uptake of Dil-ox-LDL or the expression of scavenger receptor-A (SR-A), thrombospondin receptor (CD36) and ABCG1. Taken together, these findings suggest that miR-328-5p alleviates macrophage lipid accumulation through the HDAC3/ABCA1 pathway.