Cardiovascular Management of Patients Undergoing Hematopoietic Stem Cell Transplantation: From Pretransplantation to Survivorship: A Scientific Statement From the American Heart Association.

Hematopoietic stem cell transplantation can cure various disorders but poses cardiovascular risks, especially for elderly patients and those with cardiovascular diseases. Cardiovascular evaluations are crucial in pretransplantation assessments, but guidelines are lacking. This American Heart Association scientific statement summarizes the data on transplantation-related complications and provides guidance for the cardiovascular management throughout transplantation. Hematopoietic stem cell transplantation consists of 4 phases: pretransplantation workup, conditioning therapy and infusion, immediate posttransplantation period, and long-term survivorship. Complications can occur during each phase, with long-term survivors facing increased risks for late effects such as cardiovascular disease, secondary malignancies, and endocrinopathies. In adults, arrhythmias such as atrial fibrillation and flutter are the most frequent acute cardiovascular complication. Acute heart failure has an incidence ranging from 0.4% to 2.2%. In pediatric patients, left ventricular systolic dysfunction and pericardial effusion are the most common cardiovascular complications. Factors influencing the incidence and risk of complications include pretransplantation therapies, transplantation type (autologous versus allogeneic), conditioning regimen, comorbid conditions, and patient age. The pretransplantation cardiovascular evaluation consists of 4 steps: (1) initial risk stratification, (2) exclusion of high-risk cardiovascular disease, (3) assessment of cardiac reserve, and (4) optimization of cardiovascular reserve. Clinical risk scores could be useful tools for the risk stratification of adult patients. Long-term cardiovascular management of hematopoietic stem cell transplantation survivors includes optimizing risk factors, monitoring, and maintaining a low threshold for evaluating cardiovascular causes of symptoms. Future research should prioritize refining risk stratification and creating evidence-based guidelines and strategies to optimize outcomes in this growing patient population.

Cardiovascular Imaging in Contemporary Cardio-Oncology: A Scientific Statement From the American Heart Association.

Advances in cancer therapeutics have led to dramatic improvements in survival, now inclusive of nearly 20 million patients and rising. However, cardiovascular toxicities associated with specific cancer therapeutics adversely affect the outcomes of patients with cancer. Advances in cardiovascular imaging have solidified the critical role for robust methods for detecting, monitoring, and prognosticating cardiac risk among patients with cancer. However, decentralized evaluations have led to a lack of consensus on the optimal uses of imaging in contemporary cancer treatment (eg, immunotherapy, targeted, or biological therapy) settings. Similarly, available isolated preclinical and clinical studies have provided incomplete insights into the effectiveness of multiple modalities for cardiovascular imaging in cancer care. The aims of this scientific statement are to define the current state of evidence for cardiovascular imaging in the cancer treatment and survivorship settings and to propose novel methodological approaches to inform the optimal application of cardiovascular imaging in future clinical trials and registries. We also propose an evidence-based integrated approach to the use of cardiovascular imaging in routine clinical settings. This scientific statement summarizes and clarifies available evidence while providing guidance on the optimal uses of multimodality cardiovascular imaging in the era of emerging anticancer therapies.

Myocardial steatosis across the spectrum of human health and disease.

Preclinical data strongly suggest that myocardial steatosis leads to adverse cardiac remodelling and left ventricular dysfunction. Using 1 H cardiac magnetic resonance spectroscopy, similar observations have been made across the spectrum of health and disease. The purpose of this brief review is to summarize these recent observations. We provide a brief overview of the determinants of myocardial triglyceride accumulation, summarize the current evidence that myocardial steatosis contributes to cardiac dysfunction, and identify opportunities for further research.

Rationale and design of the RAPID-WATER-FLOW trial: Radiolabeled perfusion to identify coronary artery disease using water to evaluate responses of myocardial FLOW.

OBJECTIVES: The objective of this study was to determine the diagnostic performance of 15O-water positron emission tomography (PET) myocardial perfusion imaging to detect coronary artery disease (CAD) using the truth-standard of invasive coronary angiography (ICA) with fractional flow reserve (FFR) or instantaneous wave-Free Ratio (iFR) or coronary computed tomography angiogram (CCTA). BACKGROUND: 15O-water has a very high first-pass extraction that allows accurate quantification of myocardial blood flow and detection of flow-limiting CAD. However, the need for an on-site cyclotron and lack of automated production at the point of care and relatively complex image analysis protocol has limited its clinical use to date. METHODS: The RAPID WATER FLOW study is an open-label, multicenter, prospective investigation of the accuracy of 15O-water PET to detect obstructive angiographic and physiologically significant stenosis in patients with suspected CAD. The study will include the use of an automated system for producing, dosing, and injecting 15O-water and enrolling approximately 215 individuals with suspected CAD at approximately 10 study sites in North America and Europe. The primary endpoint of the study is the diagnostic sensitivity and specificity of the 15O-water PET study using the truth-standard of ICA with FFR or iFR to determine flow-limiting stenosis, or CCTA to rule out CAD and incorporating a quantitative analytic platform developed for the 15O-water PET acquisitions. Sensitivity and specificity are to be considered positive if the lower bound of the 95% confidence interval is superior to the threshold of 60% for both, consistent with prior registration studies. Subgroup analyses include assessments of diagnostic sensitivity, specificity, and accuracy in female, obese, and diabetic individuals, as well as in those with multivessel disease. All enrolled individuals will be followed for adverse and serious adverse events for up to 32 hours after the index PET scan. The study will have >90% power (one-sided test, α = 0.025) to test the hypothesis that sensitivity and specificity of 15O-water PET are both >60%. CONCLUSIONS: The RAPID WATER FLOW study is a prospective, multicenter study to determine the diagnostic sensitivity and specificity of 15O-water PET as compared to ICA with FFR/iFR or CCTA. This study will introduce several novel aspects to imaging registration studies, including a more relevant truth standard incorporating invasive physiologic indexes, coronary CTA to qualify normal individuals for eligibility, and a more quantitative approach to image analysis than has been done in prior pivotal studies. CLINICAL TRIAL REGISTRATION INFORMATION: Clinical-Trials.gov (#NCT05134012).

Myocardial steatosis impairs left ventricular diastolic-systolic coupling in healthy humans.

Mounting evidence suggests that myocardial steatosis contributes to left ventricular diastolic dysfunction, but definitive evidence in humans is lacking due to confounding comorbidities. As such, we utilized a 48-h food restriction model to acutely increase myocardial triglyceride (mTG) content - measured by 1 H magnetic resonance spectroscopy - in 27 young healthy volunteers (13 men/14 women). Forty-eight hours of fasting caused a more than 3-fold increase in mTG content (P < 0.001). Diastolic function - defined as early diastolic circumferential strain rate (CSRd) - was unchanged following the 48-h fasting intervention, but systolic circumferential strain rate was elevated (P < 0.001), indicative of systolic-diastolic uncoupling. Indeed, in a separate control experiment in 10 individuals, administration of low-dose dobutamine (2 µg/kg/min) caused a similar change in systolic circumferential strain rate as was found during 48 h of food restriction, along with a proportionate increase in CSRd, such that the two metrics remained coupled. Taken together, these data indicate that myocardial steatosis contributes to diastolic dysfunction by impairing diastolic-systolic coupling in healthy adults, and suggest that steatosis may contribute to the progression of heart disease. KEY POINTS: Preclinical evidence strongly suggests that myocardial lipid accumulation (termed steatosis) is an important mechanism driving heart disease. Definitive evidence in humans is limited due to the confounding influence of multiple underlying comorbidities. Using a 48-h food restriction model to acutely increase myocardial triglyceride content in young healthy volunteers, we demonstrate an association between myocardial steatosis and left ventricular diastolic dysfunction. These data advance the hypothesis that myocardial steatosis may contribute to diastolic dysfunction and suggest myocardial steatosis as a putative therapeutic target.

Cardio-oncology imaging tools at the translational interface.

Cardiovascular imaging is an evolving component in the care of cancer patients. With improved survival following prompt cancer treatment, patients are facing increased risks of cardiovascular complications. While currently established imaging modalities are providing useful structural mechanical information, they continue to develop towards increased specificity. New modalities, emerging from basic science and oncology, are being translated, targeting earlier stages of cardiovascular disease. Besides these technical advances, matching an imaging modality with the patients' individual risk level for a specific pathological change is part of a successful imaging strategy. The choice of suitable imaging modalities and time points for specific patients will impact the cardio-oncological risk stratification during surveillance and follow-up monitoring. In addition, future imaging tools are poised to give us important insights into the underlying cardiovascular molecular pathology associated with cancer and oncological therapies. This review aims at giving an overview of the novel imaging technologies that have the potential to change cardio-oncological science and clinical practice in the near future.

Future Perspectives of Cardiovascular Biomarker Utilization in Cancer Survivors: A Scientific Statement From the American Heart Association.

Improving cancer survival represents the most significant effect of precision medicine and personalized molecular and immunologic therapeutics. Cardiovascular health becomes henceforth a key determinant for the direction of overall outcomes after cancer. Comprehensive tissue diagnostic studies undoubtedly have been and continue to be at the core of the fight against cancer. Will a systemic approach integrating circulating blood-derived biomarkers, multimodality imaging technologies, strategic panomics, and real-time streams of digitized physiological data overcome the elusive cardiovascular tissue diagnosis in cardio-oncology? How can such a systemic approach be personalized for application in day-to-day clinical work, with diverse patient populations, cancer diagnoses, and therapies? To address such questions, this scientific statement approaches a broad definition of the biomarker concept. It summarizes the current literature on the utilization of a multitude of established cardiovascular biomarkers at the intersection with cancer. It identifies limitations and gaps of knowledge in the application of biomarkers to stratify the cardiovascular risk before cancer treatment, monitor cardiovascular health during cancer therapy, and detect latent cardiovascular damage in cancer survivors. Last, it highlights areas in biomarker discovery, validation, and clinical application for concerted efforts from funding agencies, scientists, and clinicians at the cardio-oncology nexus.

Dual-phase imaging of cardiac metabolism using hyperpolarized pyruvate.

PURPOSE: Previous cardiac imaging studies using hyperpolarized (HP) [1-13 C]pyruvate were acquired at end-diastole (ED). Little is known about the interaction between cardiac cycle and metabolite content in the myocardium. In this study, we compared images of HP pyruvate and products at end-systole (ES) and ED. METHODS: A dual-phase 13 C MRI sequence was implemented to acquire two sequential HP images within a single cardiac cycle at ES and ED during successive R-R intervals in an interleaved manner. Each healthy volunteer (N = 3) received two injections of HP [1-13 C]pyruvate for the dual-phase imaging on the short-axis and the vertical long-axis planes. Spatial distribution of HP 13 C metabolites at each cardiac phase was correlated to multiphase 1 H MRI to confirm the mechanical changes. Ratios of myocardial HP metabolites were compared between ES and ED. Segmental analysis was performed on the midcavity short-axis plane. RESULTS: In addition to mechanical changes, metabolic profiles of the heart detected by HP [1-13 C]pyruvate differed between ES and ED. The myocardial signal of [13 C]bicarbonate relative to [1-13 C]lactate was significantly smaller at ED than the ratio at ES (p < .05), particularly in mid-anterior and mid-inferoseptal segments. The distinct metabolic profiles in the myocardium likely reflect the technical aspects of the imaging approach such as the coronary flow in addition to the cyclical changes in metabolism. CONCLUSION: The study demonstrates that metabolic profiles of the heart, measured by HP [1-13 C]pyruvate, are affected by the cardiac cycle in which that the data are acquired.

Management of Immunotherapy-Related Toxicities, Version 1.2022, NCCN Clinical Practice Guidelines in Oncology.

The aim of the NCCN Guidelines for Management of Immunotherapy-Related Toxicities is to provide guidance on the management of immune-related adverse events resulting from cancer immunotherapy. The NCCN Management of Immunotherapy-Related Toxicities Panel is an interdisciplinary group of representatives from NCCN Member Institutions, consisting of medical and hematologic oncologists with expertise across a wide range of disease sites, and experts from the areas of dermatology, gastroenterology, endocrinology, neurooncology, nephrology, cardio-oncology, ophthalmology, pulmonary medicine, and oncology nursing. The content featured in this issue is an excerpt of the recommendations for managing toxicities related to CAR T-cell therapies and a review of existing evidence. For the full version of the NCCN Guidelines, including recommendations for managing toxicities related to immune checkpoint inhibitors, visit NCCN.org.

Cardiac T2∗ measurement of hyperpolarized 13 C metabolites using metabolite-selective multi-echo spiral imaging.

PURPOSE: Noninvasive imaging with hyperpolarized (HP) pyruvate can capture in vivo cardiac metabolism. For proper quantification of the metabolites and optimization of imaging parameters, understanding MR characteristics such as T2∗ s of the HP signals is critical. This study is to measure in vivo cardiac T2∗ s of HP [1-13 C]pyruvate and the products in rodents and humans. METHODS: A dynamic 13 C multi-echo spiral imaging sequence that acquires [13 C]bicarbonate, [1-13 C]lactate, and [1-13 C]pyruvate images in an interleaved manner was implemented for a clinical 3 Tesla system. T2∗ of each metabolite was calculated from the multi-echo images by fitting the signal decay of each region of interest mono-exponentially. The performance of measuring T2∗ using the sequence was first validated using a 13 C phantom and then with rodents following a bolus injection of HP [1-13 C]pyruvate. In humans, T2∗ of each metabolite was calculated for left ventricle, right ventricle, and myocardium. RESULTS: Cardiac T2∗ s of HP [1-13 C]pyruvate, [1-13 C]lactate, and [13 C]bicarbonate in rodents were measured as 24.9 ± 5.0, 16.4 ± 4.7, and 16.9 ± 3.4 ms, respectively. In humans, T2∗ of [1-13 C]pyruvate was 108.7 ± 22.6 ms in left ventricle and 129.4 ± 8.9 ms in right ventricle. T2∗ of [1-13 C]lactate was 40.9 ± 8.3, 44.2 ± 5.5, and 43.7 ± 9.0 ms in left ventricle, right ventricle, and myocardium, respectively. T2∗ of [13 C]bicarbonate in myocardium was 64.4 ± 2.5 ms. The measurements were reproducible and consistent over time after the pyruvate injection. CONCLUSION: The proposed metabolite-selective multi-echo spiral imaging sequence reliably measures in vivo cardiac T2∗ s of HP [1-13 C]pyruvate and products.

Characterization and compensation of f0 inhomogeneity artifact in spiral hyperpolarized 13 C imaging of the human heart.

PURPOSE: This study aimed to investigate the role of regional f0 inhomogeneity in spiral hyperpolarized 13 C image quality and to develop measures to alleviate these effects. METHODS: Field map correction of hyperpolarized 13 C cardiac imaging using spiral readouts was evaluated in healthy subjects. Spiral readouts with differing duration (26 and 45 ms) but similar resolution were compared with respect to off-resonance performance and image quality. An f0 map-based image correction based on the multifrequency interpolation (MFI) method was implemented and compared to correction using a global frequency shift alone. Estimation of an unknown frequency shift was performed by maximizing a sharpness objective based on the Sobel variance. The apparent full width half at maximum (FWHM) of the myocardial wall on [13 C]bicarbonate was used to estimate blur. RESULTS: Mean myocardial wall FWHM measurements were unchanged with the short readout pre-correction (14.1 ± 2.9 mm) and post-MFI correction (14.1 ± 3.4 mm), but significantly decreased in the long waveform (20.6 ± 6.6 mm uncorrected, 17.7 ± 7.0 corrected, P = .007). Bicarbonate signal-to-noise ratio (SNR) of the images acquired with the long waveform were increased by 1.4 ± 0.3 compared to those acquired with the short waveform (predicted 1.32). Improvement of image quality was observed for all metabolites with f0 correction. CONCLUSIONS: f0 -map correction reduced blur and recovered signal from dropouts, particularly along the posterior myocardial wall. The low image SNR of [13 C]bicarbonate can be compensated with longer duration readouts but at the expense of increased f0 artifacts, which can be partially corrected for with the proposed methods.

Myocardial Steatosis Among Antiretroviral Therapy-Treated People With Human Immunodeficiency Virus Participating in the REPRIEVE Trial.

BACKGROUND: People with human immunodeficiency virus (PWH) face increased risks for heart failure and adverse heart failure outcomes. Myocardial steatosis predisposes to diastolic dysfunction, a heart failure precursor. We aimed to characterize myocardial steatosis and associated potential risk factors among a subset of the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE) participants. METHODS: Eighty-two PWH without known heart failure successfully underwent cardiovascular magnetic resonance spectroscopy, yielding data on intramyocardial triglyceride (IMTG) content (a continuous marker for myocardial steatosis extent). Logistic regression models were applied to investigate associations between select clinical characteristics and odds of increased or markedly increased IMTG content. RESULTS: Median (Q1, Q3) IMTG content was 0.59% (0.28%, 1.15%). IMTG content was increased (> 0.5%) among 52% and markedly increased (> 1.5%) among 22% of participants. Parameters associated with increased IMTG content included age (P = .013), body mass index (BMI) ≥ 25 kg/m2 (P = .055), history of intravenous drug use (IVDU) (P = .033), and nadir CD4 count < 350 cells/mm³ (P = .055). Age and BMI ≥ 25 kg/m2 were additionally associated with increased odds of markedly increased IMTG content (P = .049 and P = .046, respectively). CONCLUSIONS: A substantial proportion of antiretroviral therapy-treated PWH exhibited myocardial steatosis. Age, BMI ≥ 25 kg/m2, low nadir CD4 count, and history of IVDU emerged as possible risk factors for myocardial steatosis in this group. CLINICAL TRIALS REGISTRATION: NCT02344290; NCT03238755.

Diastolic Stress Testing Along the Heart Failure Continuum.

PURPOSE OF REVIEW: This review summarizes recent developments highlighting the clinical utility of diastolic stress testing along the heart failure continuum. RECENT FINDINGS: Invasive hemodynamic assessment of cardiac filling pressures during physiological stress is the gold-standard technique for unmasking diastolic dysfunction. Non-invasive surrogate techniques, such as Doppler ultrasound, have shown excellent agreement with invasive approaches and are now recommended by the American Society of Echocardiography and the European Association of Cardiovascular Imaging. While cycle exercise is often advocated, recent evidence supports the use of isometric handgrip as a viable alternative stressor. Diastolic stress testing is a powerful tool to enhance detection of diastolic dysfunction, is able to differentiate between cardiac and non-cardiac pathology, and should be incorporated into routine clinical assessment.