A new protocol for a single-stage combined cardiopulmonary and echocardiography exercise test: a pilot study.

Aims: The value of cardiopulmonary exercise testing (CPET) and exercise stress echocardiography (ESE) in managing cardiac disease is well known, but no standard CPET-ESE protocol is currently recommended. This pilot study aims to compare feasibility and cardiac function responses between a new high-intensity single-stage combined test (CPET-hiESE) and a standard maximal ESE (smESE). Methods and results: After screening and maximal CPET, all volunteers (n = 21) underwent three ESE modalities: (i) based on the gas exchange threshold (hiESE-GET, 40% of peak-GET, 6 min), (ii) based on heart rate (HR) (hiESE-HR, 80% of peak HR, 6 min), and (iii) smESE (85% of predicted peak HR for age, 3 min). Speckle tracking echocardiography (STE) and tissue Doppler imaging (TDI) were measured at each step. There was superior image quality and data completeness for the right ventricle strain for both hiESE modalities compared with smESE (71.4 and 76.2 vs. 42.9%, P = 0.07). Left ventricular STE data completeness was similar for all three conditions. Despite systematically higher HR, work rate and levels of exertion in the smESE compared with hiESE, STE and TDI parameters were not systematically different. Concordance correlation coefficients ranged from 0.56 to 0.88, lowest for strain rate parameters and mean difference from -0.34 to 1.53, highest for TDI measurements. Conclusion: The novel CPET-hiESE protocol allowed for better data completeness, at lower levels of exertion compared with smESE, without systematically different cardiac reserve measurements in healthy participants. This single-stage protocol can be individualized to clinical populations, which would provide practical advantages to standard testing.

Microvascular vasoregulatory dysfunction in African Americans - An enhanced opportunity for early prevention and treatment of atherosclerotic cardiovascular disease.

Atherosclerotic cardiovascular disease and its risk factors and precursors are a major driver of disparities in cardiovascular health. This review examines reported evidence that vascular endothelial dysfunction, and its manifestation as coronary microvascular dysfunction, underlies observed excess morbidity and mortality in African Americans. Advanced imaging insights that reveal patho-mechanisms, along with population evidence from the Jackson Heart Study, and the growing evidence emanating from national and international clinical trials and registries are presented. We examine a physiological framework that recognizes insulin-resistant cardiometabolic underpinnings of the conditions of the American Heart Associations' Life's Essential Eight construct of cardiovascular health as a unifying basis that affords early prevention. Mechanistic-based therapeutic approaches, can subsequently be implemented to interrupt progression to adverse outcomes employing layered, or personalized, treatment strategies of a well-defined set of conditions or diseases. Remaining knowledge gaps are acknowledged.

Multimodality Cardiac Imaging and the Imaging Workforce in the United States: Diversity, Disparities, and Future Directions.

Innovations in cardiac imaging have fundamentally advanced the understanding and treatment of cardiovascular disease. These advances in noninvasive cardiac imaging have also expanded the role of the cardiac imager and dramatically increased the demand for imagers who are cross-trained in multiple modalities. However, we hypothesize that there is significant variation in the availability of cardiac imaging expertise and a disparity in the adoption of advanced imaging technologies across the United States. To evaluate this, we have brought together the leaders of cardiovascular imaging societies, imaging trainees, as well as collaborated with national imaging accreditation commissions and imaging certification boards to assess the state of cardiac imaging and the diversity of the imaging workforce in the United States. Aggregate data confirm the presence of critical gaps, such as limited access to imaging and imaging expertise in rural communities, as well as disparities in the imaging workforce, notably among women and underrepresented minorities. Based on these results, we have proposed solutions to promote and maintain a robust and diverse community of cardiac imagers and improve equity and accessibility for cardiac imaging technologies.

Current use of real-time three-dimensional transthoracic echocardiography in animals.

This review includes 36 studies of transthoracic real-time three-dimensional echocardiography (RT3DE) in animals. Most of these studies concern cardiac chamber quantification of the left atrium and left ventricle, in dogs. Comparisons of RT3DE and different two-dimensional echocardiographic (2DE) methods have been reported in dogs with myxomatous mitral valve disease (MMVD), dilated cardiomyopathy, and in healthy control dogs. Comparisons of RT3DE and standard reference methods have been reported in healthy control dogs. In dogs with MMVD, volumetric RT3DE measurements of left atrium do not appear to provide superior prognostic value compared with 2DE methods using Simpson's method of discs in dogs with MMVD. The major advantages of RT3DE compared to 2DE include improvements in visualization of the complex morphology of the mitral valve, the estimation of mitral valve regurgitation, and improved visualization of complex congenital cardiac abnormalities.

Better Lucky Than Clever.

With an ever-expanding field of advanced cardiac imaging, clinicians tend to underestimate the importance of a detailed clinical history in reaching the correct diagnosis. This case illustrates 1 such example. (Level of Difficulty: Intermediate.).

Comparison of Four-Dimensional Flow MRI, Two-Dimensional Phase-Contrast MRI and Echocardiography in Transposition of the Great Arteries.

Pulmonary artery (PA) stenosis is a common complication after the arterial switch operation (ASO) for transposition of the great arteries (TGA). Four-dimensional flow (4D flow) CMR provides the ability to quantify flow within an entire volume instead of a single plane. The aim of this study was to compare PA maximum velocities and stroke volumes between 4D flow CMR, two-dimensional phase-contrast (2D PCMR) and echocardiography. A prospective study including TGA patients after ASO was performed between December 2018 and October 2020. All patients underwent echocardiography and CMR, including 2D PCMR and 4D flow CMR. Maximum velocities and stroke volumes were measured in the main, right, and left PA (MPA, LPA, and RPA, respectively). A total of 39 patients aged 20 ± 8 years were included. Maximum velocities in the MPA, LPA, and RPA measured by 4D flow CMR were significantly higher compared to 2D PCMR (p < 0.001 for all). PA assessment by echocardiography was not possible in the majority of patients. 4D flow CMR maximum velocity measurements were consistently higher than those by 2D PCMR with a mean difference of 65 cm/s for the MPA, and 77 cm/s for both the RPA and LPA. Stroke volumes showed good agreement between 4D flow CMR and 2D PCMR. Maximum velocities in the PAs after ASO for TGA are consistently lower by 2D PCMR, while echocardiography only allows for PA assessment in a minority of cases. Stroke volumes showed good agreement between 4D flow CMR and 2D PCMR.

Evolution of Stress Echocardiogram in the Era of CT Angiography.

The ideal diagnostic modality for acute chest pain is a highly debated topic in the cardiovascular community. With the rapid rise of coronary computed tomography angiography (CTA) and the fall of functional testing, stress echocardiography (SE) is at a delicate crossroads. Though there are many advantages of coronary CTA, it is not without its flaws. The exact realm of SE needs to be clearly defined, as well as which patients need diagnostic testing. The emergence of additional parameters will propel the evolution of modern SE. In this review article, we explore the role of SE, guidelines, comparison of SE versus CTA, and additional parameters in the coronary CTA era.

Role of advanced cardiovascular imaging in chemotherapy-induced cardiotoxicity.

The development of cardiotoxicity induced by cancer treatments has emerged as a significant clinical problem, both in the short run, as it may influence drug administration in chemotherapeutic protocols, and in the long run, because it may determine adverse cardiovascular outcomes in survivors of various malignant diseases. Therefore, early detection of anticancer drug-related cardiotoxicity is an important clinical target to improve prevention of adverse effects and patient care. Today, echocardiography is the first-line cardiac imaging techniques used for identifying cardiotoxicity. Cardiac dysfunction, clinical and subclinical, is generally diagnosed by the reduction of left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS). However, myocardial injury detected by echocardiography is preceded by other alterations, such as myocardial perfusion and mitochondrial and metabolic dysfunction, that can only be recognized by second-level imaging techniques, like cardiac magnetic resonance (CMR) and nuclear imaging, which, using targeted radiotracers, may help to provide information on the specific mechanisms of cardiotoxicity. In this review, we focus on the current and emerging role of CMR, as a critical diagnostic tool of cardiotoxicity in the very early phase, due to its availability and because it allows the contemporary detection of functional alterations, tissue alterations (mainly performed using T1, T2 mapping with the evaluation of extracellular volume-ECV) and perfusional alteration (evaluated with rest-stress perfusion) and, in the next future, even metabolic changes. Moreover, in the subsequent future, the use of Artificial Intelligence and big data on imaging parameters (CT, CMR) and oncoming molecular imaging datasets, including differences for gender and countries, may help predict cardiovascular toxicity at its earliest stages, avoiding its progression, with precise tailoring of patients' diagnostic and therapeutic pathways.

Introduction to hemodynamic forces by echocardiography.

Hemodynamic force (HDF) analysis represents a novel approach to quantify intraventricular pressure gradients, responsible for blood flow. A new mathematical model allows the derivation of HDF parameters from routine transthoracic echocardiography, making this tool more accessible for clinical use. HDF analysis is considered the fluid dynamics correlate of deformation imaging and may be even more sensitive to detect mechanical abnormalities. This has the potential to add incremental clinical value, allowing earlier detection of pathology or immediate evaluation of response to treatment. In this article, the theoretical background and physiological patterns of HDF in the left ventricle are provided. In pathological situations, the HDF pattern might alter, which is illustrated with a case of ST segment elevation myocardial infarction and non-ischemic cardiomyopathy with typical left bundle branch block.

Heart Failure and Cardiomyopathies: CT and MR from Basics to Advanced Imaging.

Since 1997, heart failure (HF) has been designated as a new epidemic. However, it is not easy to find a proper definition since different descriptors are used in clinical practice. Moreover, HF is not a single clinical entity, and there is a close relationship between HF and all cardiomyopathies (CMs). This leads us to also consider accuracy in the characterization of CMs, which is essential to define the therapeutic process of HF patients. This narrative review aims to describe the main mechanisms leading to HF in different CMs, as well as the current diagnostic and prognostic advantages deriving from advanced imaging in the cardiac field.

The Role of Cardiac Computed Tomography in Heart Failure.

PURPOSE OF REVIEW: Cardiac computed tomography (CT) is becoming a more widely applied tool in the diagnosis and management of a variety of cardiovascular conditions, including heart failure. The aim of this narrative review is to examine the role of cardiac CT in patients with heart failure. RECENT FINDINGS: Coronary computed tomographic angiography has robust diagnostic accuracy for ruling out coronary artery disease. These data are reflected in updated guidelines from major cardiology organizations. New roles for cardiac CT in myocardial imaging, perfusion scanning, and periprocedural planning, execution, and monitoring are being implemented. Cardiac CT is useful in ruling out coronary artery disease its diagnostic accuracy, accessibility, and safety. It is also intricately linked to invasive cardiac procedures that patients with heart failure routinely undergo.

Diagnosis of cardiac sarcoidosis: a primer for non-imagers.

Sarcoidosis is a multisystem granulomatous disorder that can potentially involve any organ. Cardiac involvement in sarcoidosis has been reported in up to 25% of patients based on autopsy and imaging studies. The gold standard for diagnosing cardiac sarcoidosis is endomyocardial biopsy demonstrating non-caseating granulomas; however, this technique lacks sensitivity due to the patchy nature of myocardial involvement. This, along with the non-specific clinical presentation, renders the diagnosis of cardiac sarcoidosis extremely challenging. Difficulties in obtaining histopathologic diagnosis and the advances in imaging modalities have led to a paradigm shift toward non-invasive imaging in the diagnosis of cardiac sarcoidosis. Advances in cardiac imaging modalities have also allowed unprecedented insights into the prevalence and natural history of cardiac sarcoidosis. This review discusses the role of non-invasive imaging for diagnosis, risk stratification, and monitoring the response to therapies in cardiac sarcoidosis. Echocardiography remains the first-line modality due to widespread availability and affordability. Cardiac magnetic resonance imaging (CMR) can be used to study cardiac structure, function, and most importantly tissue characterization to detect inflammation and fibrosis. Fluoro-deoxy glucose positron emission tomography (FDG PET) is the gold standard for non-invasive detection of cardiac inflammation, and it offers the unique ability to assess response to therapeutic interventions. Hybrid imaging is a promising technique that allows us to combine the unique strengths of CMR and FDG PET. Understanding the advantages and disadvantages of each of these imaging modalities is crucial in order to tailor the diagnostic algorithm and utilize the most appropriate modality for each patient.

Nuclear cardiology: state of the art.

Radionuclide imaging remains an essential component of modern cardiology. There is overlap with the information from other imaging techniques, but no technique is static and new developments have expanded its role. This review focuses on ischaemic heart disease, heart failure, infection and inflammation. Radiopharmaceutical development includes the wider availability of positron emission tomography (PET) tracers such as rubidium-82, which allows myocardial perfusion to be quantified in absolute terms. Compared with alternative techniques, myocardial perfusion scintigraphy PET and single photon emission computed tomography (SPECT) have the advantages of being widely applicable using exercise or pharmacological stress, full coverage of the myocardium and a measure of ischaemic burden, which helps to triage patients between medical therapy and revascularisation. Disadvantages include the availability of expertise in some cardiac centres and the lack of simple SPECT quantification, meaning that global abnormalities can be underestimated. In patients with heart failure, despite the findings of the STICH (Surgical Treatment for Ischemic Heart Failure) trial, there are still data to support the assessment of myocardial hibernation in predicting when abolition of ischaemia might lead to improvement in ventricular function. Imaging of sympathetic innervation is well validated, but simpler markers of prognosis mean that it has not been widely adopted. There are insufficient data to support its use in predicting the need for implanted devices, but non-randomised studies are promising. Other areas where radionuclide imaging is uniquely valuable are detection and monitoring of endocarditis, device infection, myocardial inflammation in sarcoidosis, myocarditis and so on, and reliable detection of deposition in suspected transthyretin-related amyloidosis.

Cardiovascular magnetic resonance imaging: emerging techniques and applications.

This review gives examples of emerging cardiovascular magnetic resonance (CMR) techniques and applications that have the potential to transition from research to clinical application in the near future. Four-dimensional flow CMR (4D-flow CMR) allows time-resolved three-directional, three-dimensional (3D) velocity-encoded phase-contrast imaging for 3D visualisation and quantification of valvular or intracavity flow. Acquisition times of under 10 min are achievable for a whole heart multidirectional data set and commercial software packages are now available for data analysis, making 4D-flow CMR feasible for inclusion in clinical imaging protocols. Diffusion tensor imaging (DTI) is based on the measurement of molecular water diffusion and uses contrasting behaviour in the presence and absence of boundaries to infer tissue structure. Cardiac DTI is capable of non-invasively phenotyping the 3D micro-architecture within a few minutes, facilitating transition of the method to clinical protocols. Hybrid positron emission tomography-magnetic resonance (PET-MR) provides quantitative PET measures of biological and pathological processes of the heart combined with anatomical, morphological and functional CMR imaging. Cardiac PET-MR offers opportunities in ischaemic, inflammatory and infiltrative heart disease.

Contrast echocardiography: current status and future directions.

Contrast echocardiography is a family of ultrasound-based procedures, whereby acoustic enhancing agents, usually microbubbles, are administered by intravenous route and detected in order to improve diagnostic performance. This review describes: (1) the agents that have been designed for diagnostic imaging, (2) current clinical applications where either left ventricular opacification or microvascular perfusion imaging with myocardial contrast echocardiography have been demonstrated to provide incremental information to non-contrast echocardiography and (3) future diagnostic and therapeutic applications of contrast ultrasound that rely on unique compositional design of ultrasound-enhancing agents.

The prognostic role of speckle tracking echocardiography in clinical practice: evidence and reference values from the literature.

Speckle tracking echocardiography (STE) is a second-level echocardiographic technique which has gradually gained relevance in the last years. It allows semi-automatic quantification of myocardial deformation and function, overcoming most of the limitations characterizing basic echocardiography and providing an early detection of cardiac impairment. Today, its feasibility and usefulness are highly supported by literature. In particular, several studies demonstrated that STE could provide additional prognostic information beyond conventional echocardiographic and traditional clinical parameters. Moreover, a recent standardization of speckle tracking analysis regarding all cardiac chambers paved the way for the integration of STE in diagnostic and prognostic protocols for particular clinical settings. The aim of this review is to describe the prognostic role of STE in different clinical scenarios basing on currently available evidence.

Association between right ventricular strain and outcomes in patients with dilated cardiomyopathy.

OBJECTIVE: To explore the association between three-dimensional (3D) cardiac magnetic resonance (CMR) feature tracking (FT) right ventricular peak global longitudinal strain (RVpGLS) and major adverse cardiovascular events (MACEs) in patients with stage C or D heart failure (HF) with non-ischaemic dilated cardiomyopathy (NIDCM) but without atrial fibrillation (AF). METHODS: Patients with dilated cardiomyopathy were enrolled in this prospective cohort study. Comprehensive clinical and biochemical analysis and CMR imaging were performed. All patients were followed up for MACEs. RESULTS: A total of 192 patients (age 53±14 years) were eligible for this study. A combination of cardiovascular death and cardiac transplantation occurred in 18 subjects during the median follow-up of 567 (311, 920) days. Brain natriuretic peptide, creatinine, left ventricular (LV) end-diastolic volume, LV end-systolic volume, right ventricular (RV) end-diastolic volume and RVpGLS from CMR were associated with the outcomes. The multivariate Cox regression model adjusting for traditional risk factors and CMR variables detected a significant association between RVpGLS and MACEs in patients with stage C or D HF with NIDCM without AF. Kaplan-Meier analysis based on RVpGLS cut-off value revealed that patients with RVpGLS <-8.5% showed more favourable clinical outcomes than those with RVpGLS ≥-8.5% (p=0.0037). Subanalysis found that this association remained unchanged. CONCLUSIONS: RVpGLS-derived from 3D CMR FT is associated with a significant prognostic impact in patients with NIDCM with stage C or D HF and without AF.

Augmentation of pulmonary blood flow and cardiac output by non-invasive external ventilation late after Fontan palliation.

OBJECTIVES: Although a life-preserving surgery for children with single ventricle physiology, the Fontan palliation is associated with striking morbidity and mortality with advancing age. Our primary objective was to evaluate the impact of non-invasive, external, thoraco-abdominal ventilation on pulmonary blood flow (PBF) and cardiac output (CO) as measured by cardiovascular magnetic resonance (CMR) imaging in adult Fontan subjects. METHODS: Adults with a dominant left ventricle post-Fontan palliation (lateral tunnel or extracardiac connections) and healthy controls matched by sex and age were studied. We evaluated vascular flows using phase-contrast CMR imaging during unassisted breathing, negative pressure ventilation (NPV) and biphasic ventilation (BPV). Measurements were made within target vessels (aorta, pulmonary arteries, vena cavae and Fontan circuit) at baseline and during each ventilation mode. RESULTS: Ten Fontan subjects (50% male, 24.5 years (IQR 20.8-34.0)) and 10 matched controls were studied. Changes in PBF and CO, respectively, were greater following BPV as compared with NPV. In subjects during NPV, PBF increased by 8% (Δ0.20 L/min/m2 (0.10-0.53), p=0.011) while CO did not change significantly (Δ0.17 L/min/m2 (-0.11-0.23), p=0.432); during BPV, PBF increased by 25% (Δ0.61 L/min/m2 (0.20-0.84), p=0.002) and CO increased by 16% (Δ0.47 L/min/m2 (0.21-0.71), p=0.010). Following BPV, change in PBF and CO were both significantly higher in subjects versus controls (0.61 L/min/m2 (0.2-0.84) vs -0.27 L/min/m2 (-0.55-0.13), p=0.001; and 0.47 L/min/m2 (0.21-0.71) vs 0.07 L/min/m2 (-0.47-0.33), p=0.034, respectively). CONCLUSION: External ventilation acutely augments PBF and CO in adult Fontan subjects. Confirmation of these findings in larger populations with longer duration of ventilation and extended follow-up will be required to determine sustainability of haemodynamic effects.

Trabeculated Myocardium in Hypertrophic Cardiomyopathy: Clinical Consequences.

AIMS: Hypertrophic cardiomyopathy (HCM) is often accompanied by increased trabeculated myocardium (TM)-which clinical relevance is unknown. We aim to measure the left ventricular (LV) mass and proportion of trabeculation in an HCM population and to analyze its clinical implication. METHODS AND RESULTS: We evaluated 211 patients with HCM (mean age 47.8 ± 16.3 years, 73.0% males) with cardiac magnetic resonance (CMR) studies. LV trabecular and compacted mass were measured using dedicated software for automatic delineation of borders. Mean compacted myocardium (CM) was 160.0 ± 62.0 g and trabecular myocardium (TM) 55.5 ± 18.7 g. The percentage of trabeculated myocardium (TM%) was 26.7% ± 6.4%. Females had significantly increased TM% compared to males (29.7 ± 7.2 vs. 25.6 ± 5.8, p < 0.0001). Patients with LVEF < 50% had significantly higher values of TM% (30.2% ± 6.0% vs. 26.6% ± 6.4%, p = 0.02). Multivariable analysis showed that female gender and neutral pattern of hypertrophy were directly associated with TM%, while dynamic obstruction, maximal wall thickness and LVEF% were inversely associated with TM%. There was no association between TM% with arterial hypertension, physical activity, or symptoms. Atrial fibrillation and severity of hypertrophy were the only variables associated with cardiovascular death. Multivariable analysis failed to demonstrate any correlation between TM% and arrhythmias. CONCLUSIONS: Approximately 25% of myocardium appears non-compacted and can automatically be measured in HCM series. Proportion of non-compacted myocardium is increased in female, non-obstructives, and in those with lower contractility. The amount of trabeculation might help to identify HCM patients prone to systolic heart failure.