Diffuse myocardial fibrosis by T1-mapping in children with subclinical anthracycline cardiotoxicity: relationship to exercise capacity, cumulative dose and remodeling

Pediatric Cardio-Oncology: Screening, Risk Stratification, and Prevention of Cardiotoxicity Associated with Anthracyclines

Anthracyclines have significantly improved the survival of children with malignant tumors, but the associated cardiotoxicity, an effect now under the purview of pediatric cardio-oncology, due to its cumulative and irreversible effects on the heart, limits their clinical application. A systematic screening and risk stratification approach provides the opportunity for early identification and intervention to mitigate, reverse, or prevent myocardial injury, remodeling, and dysfunction associated with anthracyclines. This review summarizes the risk factors, surveillance indexes, and preventive strategies of anthracycline-related cardiotoxicity to improve the safety and efficacy of anthracyclines.

T1 Mapping in Cardiovascular Magnetic Resonance-A Marker of Diffuse Myocardial Fibrosis in Patients Undergoing Hematopoietic Stem Cell Transplantation

Introduction: Hematopoietic stem cell transplantation (HSCT) recipients are at increased risk of cardiovascular diseases. In our study, we aimed to find subclinical changes in myocardial tissue after HSCT with the help of cardiovascular magnetic resonance (CMR) tissue imaging techniques. Methods: The data of 44 patients undergoing autologous and allogeneic HSCT in the Hospital of Lithuanian University of Health Sciences Kaunas Clinics from October 2021 to February 2023 were analyzed. Bioethics approval for the prospective study was obtained (No BE-2-96). CMR was performed two times: before enrolling for the HSCT procedure (before starting mobilization chemotherapy for autologous HSCT and before starting the conditioning regimen for allogeneic HSCT) and 12 ± 1 months after HSCT. LV end-diastolic volume, LV end-systolic volume, LV mass and values indexed to body surface area (BSA), and LV ejection fraction were calculated. T1 and T2 mapping values were measured. Results: There was a statistically significant change in T1 mapping values. Before HSCT, mean T1 mapping was 1226.13 ± 39.74 ms, and after HSCT, it was 1248.70 ± 41.07 ms (p = 0.01). The other parameters did not differ significantly. Conclusions: Increases in T1 mapping values following HSCT can show the progress of diffuse myocardial fibrosis and may reflect subclinical injury. T2 mapping values remain the same and do not show edema and active inflammation processes at 12 months after HSCT.

The Significance of Parametric Mapping in Advanced Cardiac Imaging

Cardiac magnetic resonance imaging has witnessed a transformative shift with the integration of parametric mapping techniques, such as T1 and T2 mapping and extracellular volume fraction. These techniques play a crucial role in advancing our understanding of cardiac function and structure, providing unique insights into myocardial tissue properties. Native T1 mapping is particularly valuable, correlating with histopathological fibrosis and serving as a marker for various cardiac pathologies. Extracellular volume fraction, an early indicator of myocardial remodeling, predicts adverse outcomes in heart failure. Elevated T2 relaxation time in cardiac MRI indicates myocardial edema, enabling noninvasive and early detection in conditions like myocarditis. These techniques offer precise insights into myocardial properties, enhancing the accuracy of diagnosis and prognosis across a spectrum of cardiac conditions, including myocardial infarction, autoimmune diseases, myocarditis, and sarcoidosis. Emphasizing the significance of these techniques in myocardial tissue analysis, the review provides a comprehensive overview of their applications and contributions to our understanding of cardiac diseases.

Myocardial extracellular volume derived from contrast-enhanced chest computed tomography in longitudinal evaluation of cardiac toxicity in patients treated with immune checkpoint inhibitors

Background

The immune-related adverse effects after immune checkpoint inhibitors (ICIs) treatment have always been a hot topic. Although the incidence of myocarditis is not high among the related adverse effects, the mortality rate is extremely high once it occurs. In the past, the risk of cancer therapy-related cardiac dysfunction (CTRCD) after drug treatment was evaluated based on imaging examinations, but this evaluation still had certain limitations. Currently, the extracellular volume (ECV) score measurement calculated using cardiac magnetic resonance T1 mapping has become a reliable method for evaluating myocardial toxicity and computed tomography (CT) examination may become an alternative. This study aimed to longitudinally evaluate the cardiac toxicity of patients treated with ICIs using myocardial ECV derived from contrast-enhanced chest CT.

Methods

A total of 500 patients with III-IV lung cancer and esophageal cancer treated with ICIs were evaluated. Participants underwent baseline examination and at least 1 follow-up examination after treatment. Contrast-enhanced chest CT-ECV, left ventricular ejection fraction (LVEF), and measurement of cardiac troponin T (cTnT) were conducted before the first treatment, 3-6 months after the first treatment, and about 12 months after the first treatment, respectively. The ECV value of the middle part of the left ventricular septum was evaluated on CT venography and plain scan, the LVEF value was evaluated by color Doppler ultrasound, and the quantity of cTnT was detected by chemiluminescence. Cancer therapy-related cardiac dysfunction was recorded.

Results

The mean baseline LVEF value was 68.51%±4.81% (N0=500), and those of LVEF1, LVEF2, and LVEF3 were 68.77%±4.30%, 68.16%±3.59%, and 66.23%±4.20%, respectively (N1=500, N2=467, and N3=361, respectively). There was no significant difference between LVEF1, LVEF2, and LVEF0 (P1=0.095, P2=0.062), whereas LVEF3 was significantly lower than LVEF0 (P<0.001). The average baseline cTnT0 value was 7.42±3.95 (N0=500). The values of cTnT1, cTnT2, and cTnT3 were 10.05±11.40, 12.24±13.59, and 14.54±14.49, respectively (N1=500, N2=467, N3=361). The values of cTnT1, cTnT2, and cTnT3 were significantly higher than cTnT0 (P1<0.001, P2<0.001, P3<0.001). The average ECV0 was 47.14%±7.48% (N0=500). ECV1, ECV2, and ECV3 were 50.85%±6.79%, 53.44%±6.96% and 52.64%±7.58% respectively (N1=500, N2=467 and N3=361). ECV1, ECV2, and ECV3 were significantly higher than ECV0 (P1<0.001, P2<0.001, P3<0.001). CTRCD occurred in 49 patients. There were significant differences between the CTRCD (+) group and the CTRCD (-) group in cTnT1, cTnT2, and cTnT3 (P1<0.001, P2<0.001, and P3<0.001, respectively) and in ECV1, ECV2, and ECV3 (P1=0.039, P2=0.041, and P3=0.013, respectively).

Conclusions

CT-ECV began to increase at the early stage after the treatment of ICIs. CT-ECV is a potential biomarker for dynamically monitoring the cardiac toxicity of tumor patients after receiving ICIs. ECV may be used to speculate the CTRCD caused by the treatment of ICIs.

MRI-derived extracellular volume as a biomarker of cancer therapy cardiotoxicity: systematic review and meta-analysis

OBJECTIVES

MRI-derived extracellular volume (ECV) allows characterization of myocardial changes before the onset of overt pathology, which may be caused by cancer therapy cardiotoxicity. Our purpose was to review studies exploring the role of MRI-derived ECV as an early cardiotoxicity biomarker to guide timely intervention.

MATERIALS AND METHODS

In April 2022, we performed a systematic search on EMBASE and PubMed for articles on MRI-derived ECV as a biomarker of cancer therapy cardiotoxicity. Two blinded researchers screened the retrieved articles, including those reporting ECV values at least 3 months from cardiotoxic treatment. Data extraction was performed for each article, including clinical and technical data, and ECV values. Pooled ECV was calculated using the random effects model and compared among different treatment regimens and among those who did or did not experience overt cardiac dysfunction. Meta-regression analyses were conducted to appraise which clinical or technical variables yielded a significant impact on ECV.

RESULTS

Overall, 19 studies were included. Study populations ranged from 9 to 236 patients, for a total of 1123 individuals, with an average age ranging from 12.5 to 74 years. Most studies included patients with breast or esophageal cancer, treated with anthracyclines and chest radiotherapy. Pooled ECV was 28.44% (95% confidence interval, CI, 26.85-30.03%) among subjects who had undergone cardiotoxic cancer therapy, versus 25.23% (95%CI 23.31-27.14%) among those who had not (p = .003).

CONCLUSION

A higher ECV in patients who underwent cardiotoxic treatment could imply subclinical changes in the myocardium, present even before overt cardiac pathology is detectable.

CLINICAL RELEVANCE STATEMENT

The ability to detect subclinical changes in the myocardium displayed by ECV suggests its use as an early biomarker of cancer therapy-related cardiotoxicity.

KEY POINTS

• Cardiotoxicity is a common adverse effect of cancer therapy; therefore, its prompt detection could improve patient outcomes. • Pooled MRI-derived myocardial extracellular volume was higher in patients who underwent cardiotoxic cancer therapy than in those who did not (28.44% versus 25.23%, p = .003). • MRI-derived myocardial extracellular volume represents a potential early biomarker of cancer therapy cardiotoxicity.

Anthracycline-induced cardiotoxicity on regional myocardial work and left ventricular mechanical dispersion in adolescents and young adults in post-lymphoma remission

BACKGROUND

Myocardial work (MW) is a new echocardiographic tool with a high sensitivity to detect early and subtle alterations of myocardial function. We aimed to evaluate the late effects of anthracyclines by assessing the global and segmental MW and intraventricular mechanical dispersion from speckle tracking echocardiography in childhood lymphoma survivors (CLS).

METHODS

Thirty-one young adults including CLS and age-matched healthy controls were enrolled. All underwent echocardiography including an evaluation of left ventricular (LV) morphology and regional function. We assessed LV longitudinal (differentiating sub-endocardial and sub-epicardial layers), circumferential strains and twist, global and regional MW index (MWI). LV mechanical dispersion was assessed from the time dispersion of LV longitudinal strain, from myocardial wasted work (MWW) and myocardial work efficiency (MWE).

RESULTS

The longitudinal strains both at the level of the sub-endocardium and sub-epicardium were reduced in CLS compared to controls. The global MWI was also decreased (1668 ± 266 vs 1870 ± 264%.mmHg in CLS patients and controls, respectively, p < 0.05), especially on the apical segments. An increase of LV intraventricular mechanical dispersion was observed in CLS. MWW and MWE remained unchanged compared to controls.

CONCLUSION

Our results strongly support that cardiac remodeling is observed in CLS, characterized by a decrease in MW and an increase in LV mechanical dispersion. The apex is specifically altered, but its clinical significance remains uncertain. MW as a complement to strain seems interesting in cancer survivors to detect myocardial dysfunction at early stage and adapt their follow-up.

Myocardial late enhancement and extracellular volume with single-energy, dual-energy, and photon-counting computed tomography

Computed tomography late enhancement (CT-LE) is emerging as a non-invasive technique for cardiac diagnosis with wider accessibility compared to MRI, despite its typically lower contrast-to-noise ratio. Optimizing CT-LE image quality necessitates a thorough methodology addressing contrast administration, timing, and radiation dose, alongside a robust understanding of extracellular volume (ECV) quantification methods. This review summarizes CT-LE protocols, clinical utility, and advances in ECV measurement through both single-energy and dual-energy CT. It also highlights photon-counting detector CT technology as an innovative means to potentially improve image quality and reduce radiation exposure.

Multimodality Cardiovascular Imaging of Cardiotoxicity Due to Cancer Therapy

Cancer therapies have revolutionized patient survival rates, yet they come with the risk of cardiotoxicity, necessitating effective monitoring and management. The existing guidelines offer a limited empirical basis for practical approaches in various clinical scenarios. This article explores the intricate relationship between cancer therapy and the cardiovascular system, highlighting the role of advanced multimodality imaging in monitoring patients before, during, and after cancer treatment. This review outlines the cardiovascular effects of different cancer therapy classes, offering a comprehensive understanding of their dose- and time-dependent impacts. This paper delves into diverse imaging modalities such as echocardiography, cardiac magnetic resonance imaging, cardiac computed tomography, and nuclear imaging, detailing their strengths and limitations in various conditions due to cancer treatment, such as cardiac dysfunction, myocarditis, coronary artery disease, Takotsubo cardiomyopathy, pulmonary hypertension, arterial hypertension, valvular heart diseases, and heart failure with preserved ejection fraction. Moreover, it underscores the significance of long-term follow-up for cancer survivors and discusses future directions.

Multimodal Imaging of Cancer Therapy-Related Cardiac Dysfunction in Breast Cancer-A State-of-the-Art Review

BACKGROUND

This review focuses on multimodality imaging of cardiotoxicity in cancer patients, with the aim of evaluating the effectiveness of different techniques in detecting and monitoring cardiac changes associated with cancer therapy.

METHODS

Eight studies were included in the review, covering various imaging modalities such as cardiac magnetic resonance imaging, echocardiography, and multigated acquisition scanning.

RESULTS

Cardiac magnetic resonance imaging emerged as the most definitive modality, offering real-time detection, comprehensive assessment of cardiac function, the ability to detect early myocardial changes, and superior detection of cardiotoxicity when compared to the other imaging modalities. The studies also emphasize the importance of parameters such as left ventricular ejection fraction and global longitudinal strain in assessing cardiac function and predicting cardiotoxicity.

CONCLUSION

Due to the common use of HER2 agents and anthracyclines within the breast cancer population, the LVEF as a critical prognostic measurement for assessing heart health and estimating the severity of left-sided cardiac malfunction is a commonly used endpoint. CTRCD rates differed between imaging modalities, with cardiac MRI the most sensitive. The use of multimodal cardiac imaging remains a nuanced area, influenced by local availability, the clinical question at hand, body habits, and medical comorbidities. All of the imaging modalities listed have a role to play in current care; however, focus should be given to increasing the provision of cardiac MRI for breast cancer patients in the future to optimize the detection of CTRCD and patient outcomes thereafter.

Chemotherapy effect on myocardial fibrosis markers in patients with gynecologic cancer and low cardiovascular risk

Background

Patients with gynecologic cancers experience side effects of chemotherapy cardiotoxicity. We aimed to quantify cardiac magnetic resonance (CMR) markers of myocardial fibrosis in patients with gynecologic cancer and low cardiovascular risk who undergo chemotherapy.

Methods

This study is part of a registered clinical research. CMR T1 mapping was performed in patients with gynecologic cancer and low cardiovascular risk undergoing chemotherapy. The results were compared with those of age-matched healthy control subjects.

Results

68 patients (median age = 50 years) and 30 control subjects were included. The median number of chemotherapy cycles of patients was 9.0 (interquartile range [IQR] 3.3-17.0). Extracellular volume fraction (ECV) (27.2% ± 2.7% vs. 24.5% ± 1.7%, P < 0.001) and global longitudinal strain (-16.2% ± 2.8% vs. -17.4% ± 2.0%, P = 0.040) were higher in patients compared with controls. Patients with higher chemotherapy cycles (>6 cycles) (n=41) had significantly lower intracellular mass indexed (ICMi) compared with both patients with lower chemotherapy cycles (≤6 cycles) (n=27) (median 27.44 g/m2 [IQR 24.03-31.15 g/m2] vs. median 34.30 g/m2 [IQR 29.93-39.79 g/m2]; P = 0.002) and the control group (median 27.44 g/m2 [IQR 24.03-31.15 g/m2] vs. median 32.79 g/m2 [IQR 27.74-35.76 g/m2]; P = 0.002). Patients with two or more chemotherapy regimens had significantly lower ICMi compared with both patients with one chemotherapy regimen (27.45 ± 5.16 g/m2 vs. 33.32 ± 6.42 g/m2; P < 0.001) and the control group (27.45 ± 5.16 g/m2 vs. 33.02 ± 5.52 g/m2; P < 0.001). The number of chemotherapy cycles was associated with an increase in the ECV (Standard regression coefficient [β] = 0.383, P = 0.014) and a decrease in the ICMi (β = -0.349, P = 0.009).

Conclusion

Patients with gynecologic cancer and low cardiovascular risk who undergo chemotherapy have diffuse extracellular volume expansion, which is obvious with the increase of chemotherapy cycles. Myocyte loss may be part of the mechanism in patients with a higher chemotherapy load.

Clinical trial registration

http://www.chictr.org.cn, identifier ChiCTR-DDD-17013450.

Left Ventricle Size Correlates with Peak Exercise Capacity in Pediatric Cancer Survivors Exposed to Anthracycline Chemotherapy

Cancer survivors exposed to anthracycline chemotherapy are at risk for developing cardiomyopathy, which may have delayed clinical manifestation. In a retrospective cross-sectional study, we evaluated the utility of cardiopulmonary exercise testing (CPET) for detecting early cardiac disease in 35 pediatric cancer survivors by examining the associations between peak exercise capacity (measured via percent predicted peak VO2) and resting left ventricular (LV) function on echocardiography and cardiac magnetic resonance imaging (cMRI). We additionally assessed the relationships between LV size on resting echocardiography or cMRI and percent predicted peak VO2 since LV growth arrest can occur in anthracycline-exposed patients prior to changes in LV systolic function. We found reduced exercise capacity in this cohort, with low percent predicted peak VO2 (62%, IQR: 53-75%). While most patients in our pediatric cohort had normal LV systolic function, we observed associations between percent predicted peak VO2 and echocardiographic and cMRI measures of LV size. These findings indicate that CPET may be more sensitive in manifesting early anthracycline-induced cardiomyopathy than echocardiography in pediatric cancer survivors. Our study also highlights the importance of assessing LV size in addition to function in pediatric cancer survivors exposed to anthracyclines.

Nanotechnology Approaches for Prevention and Treatment of Chemotherapy-Induced Neurotoxicity, Neuropathy, and Cardiomyopathy in Breast and Ovarian Cancer Survivors

Nanotechnology has emerged as a promising approach for the targeted delivery of therapeutic agents while improving their efficacy and safety. As a result, nanomaterial development for the selective targeting of cancers, with the possibility of treating off-target, detrimental sequelae caused by chemotherapy, is an important area of research. Breast and ovarian cancer are among the most common cancer types in women, and chemotherapy is an essential treatment modality for these diseases. However, chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy are common side effects that can affect breast and ovarian cancer survivors quality of life. Therefore, there is an urgent need to develop effective prevention and treatment strategies for these adverse effects. Nanoparticles (NPs) have extreme potential for enhancing therapeutic efficacy but require continued research to elucidate beneficial interventions for women cancer survivors. In short, nanotechnology-based approaches have emerged as promising strategies for preventing and treating chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy. NP-based drug delivery systems and therapeutics have shown potential for reducing the side effects of chemotherapeutics while improving drug efficacy. In this article, the latest nanotechnology approaches and their potential for the prevention and treatment of chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy in breast and ovarian cancer survivors are discussed.

Cardiac Imaging in Childhood Cancer Survivors: A State-of-the-Art Review

Childhood cancer survival has improved significantly in the past few decades, reaching rates of 80% or more at 5 years. However, with improved survival, early- and late-occurring complications of chemotherapy and radiotherapy exposure are becoming progressively more evident. Cardiovascular diseases represent the leading cause of non-oncological morbidity and mortality in this highly vulnerable population. Therefore, the necessity of reliable, noninvasive screening tools able to early identify cardiac complications early is now pre-eminent in order to implement prevention strategies and mitigate disease progression. Echocardiography, may allow identification of myocardial dysfunction, pericardial complications, and valvular heart diseases. However, additional imaging modalities may be necessary in selected cases. This manuscript provides an in-depth review of noninvasive imaging parameters studied in childhood cancer survivors. Furthermore, we will illustrate brief surveillance recommendations according to available evidence and future perspectives in this expanding field.

Cardio-Oncology in Childhood: State of the Art

PURPOSE OF REVIEW

Cardio-oncology is an increasingly important field of cardiology that focuses on the detection, monitoring, and treatment of cardiovascular disease (CVD) occurring during and after oncological treatments. The survival rate for childhood cancer patients has dramatically increased thanks to new treatment protocols and cardiovascular (CV) sequelae represent the third most frequent cause of mortality in surviving patients. This study aims to provide a complete and updated review of all the main aspects of cardio-oncology in childhood and to highlight the critical issues.

RECENT FINDINGS

The problem of CV complications in childhood cancer survivors raises the need to make an early diagnosis of cardiotoxicity by the new imaging and laboratory techniques in order to intervene promptly and to implement pharmacological strategies and lifestyle changes to reduce or even to prevent cardiac injury. Furthermore, a stratification of CV risk, also including new predisposing factors such as the presence of some genetic mutations, is of paramount importance before undertaking oncological treatments. Besides, a systematic and personalized planning of long-term follow-up is fundamental to ensure a transition from pediatric to adult hospital and to avoid missed or late diagnosis of cardiomyopathy. We reviewed the main risk factors for cardiotoxicity in children, both traditional and emerging ones: the mechanisms of toxicity of both old and new antineoplastic therapies, the techniques for detecting cardiac damage, and the current evidence regarding pharmacological cardioprotection. At the end, we focused our attention on the existing guidelines and strategies about the long-term follow-up of childhood cancer survivors.

Influence of extracellular volume fraction on peak exercise oxygen pulse following thoracic radiotherapy

Background

Radiation-induced myocardial fibrosis increases heart failure (HF) risk and is associated with a restrictive cardiomyopathy phenotype. The myocardial extracellular volume fraction (ECVF) using contrast-enhanced cardiac magnetic resonance (CMR) quantifies the extent of fibrosis which, in severe cases, results in a noncompliant left ventricle (LV) with an inability to augment exercise stroke volume (SV). The peak exercise oxygen pulse (O₂Pulse), a noninvasive surrogate for exercise SV, may provide mechanistic insight into cardiac reserve. The relationship between LV ECVF and O₂Pulse following thoracic radiotherapy has not been explored.

Methods

Patients who underwent thoracic radiotherapy for chest malignancies with significant incidental heart dose (≥5 Gray (Gy), ≥10% heart) without a pre-cancer treatment history of HF underwent cardiopulmonary exercise testing to determine O₂Pulse, contrast-enhanced CMR, and N-terminal pro-brain natriuretic peptide (NTproBNP) measurement. Multivariable-analyses were performed to identify factors associated with O₂Pulse normalized for age/gender/anthropometrics.

Results

Thirty patients (median [IQR] age 63 [57–67] years, 18 [60%] female, 2.0 [0.6–3.8] years post-radiotherapy) were included. The peak VO₂ was 1376 [1057–1552] mL·min^− 1, peak HR = 150 [122–164] bpm, resulting in an O₂Pulse of 9.2 [7.5–10.7] mL/beat or 82 (66–96) % of predicted. The ECVF, LV ejection fraction, heart volume receiving ≥10 Gy, and NTproBNP were independently associated with %O₂Pulse (P < .001).

Conclusions

In patients with prior radiotherapy heart exposure, %-predicted O₂Pulse is inversely associated markers of diffuse fibrosis (ECVF), ventricular wall stress (NTproBNP), radiotherapy heart dose, and positively related to LV function. Increased LV ECVF may reflect a potential etiology of impaired LV SV reserve in patients receiving thoracic radiotherapy for chest malignancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40959-021-00127-6.

Early myocardial oedema can predict subsequent cardiomyopathy in high-dose anthracycline therapy

AIMS

This study aims to assess subclinical changes in functional and morphologic myocardial MR parameters very early into a repetitive high-dose anthracycline treatment (planned cumulative dose >650 mg/m² ), which may predict subsequent development of anthracycline-induced cardiomyopathy (aCMP).

METHODS

Thirty sarcoma patients with previous exposition of 300-360 mg/m² doxorubicin-equivalent chemotherapy who were planned for a second treatment of anthracycline-based chemotherapy (360 mg/m² doxorubicin-equivalent) were recruited. Enrolled individuals received three CMR studies (before treatment, 48 h after first anthracycline treatment and upon completion of treatment). Native T1 mapping (MOLLI 5s(3s)3s), T2 mapping, and extracellular volume (ECV) maps were acquired in addition to a conventional CMR with SSFP-cine imaging at 1.5 T. Patients were given 0.2 mmol/kg gadoteridol for ECV quantification and LGE imaging. Blood samples for cardiac biomarkers were obtained before each scan. Development of relevant aCMP was defined as drop of left ventricular ejection fraction (LVEF) by >10% compared with baseline.

RESULTS

Twenty-three complete datasets were available for analysis. Median treatment time was 20.7 ± 3.0 weeks. Eight patients developed aCMP with LVEF reduction >10% until end of chemotherapy. Baseline LVEF was not different between patients with and without subsequent aCMP. Patients with aCMP had decreased LV mass upon completion of therapy (99.4 ± 26.5 g vs. 90.3 ± 24.8 g; P = 0.02), whereas patients without aCMP did not show a change in LV mass (91.5 ± 20.0 g vs. 89.0 ± 23.6 g; P > 0.05). On strain analysis, GLS (-15.3 ± 1.3 vs. -13.4 ± 1.6; P = 0.02) and GCS (-16.7 ± 2.1 vs. -14.9 ± 2.6; P = 0.04) were decreased in aCMP patients upon completion of therapy, whereas non-aCMP individuals showed no change in GLS (-15.4 ± 3.3 vs. -15.4 ± 3.4; P = 0.97). When assessed 48 h after first dose of anthracyclines, patients with subsequent aCMP had significantly elevated myocardial T2 times compared with before therapy (53.0 ± 2.8 ms vs. 49.3 ± 5.2 ms, P = 0.02) than patients who did not develop aCMP (50.7 ± 5.1 ms vs. 51.1 ± 3.9 ms, P > 0.05). Native T1 times decreased at 48 h after first dose irrespective of development of subsequent aCMP (1020.2 ± 28.4 ms vs. 973.5 ± 40.3 ms). Upon completion of therapy, patients with aCMP had increased native T1 compared with baseline (1050.8 ± 17.9 ms vs. 1022.4 ± 22.0 ms; P = 0.01), whereas non-aCMP patients did not (1034.5 ± 46.6 ms vs. 1018.4 ± 29.7 ms; P = 0.15). No patient developed new myocardial scars or compact myocardial fibrosis under chemotherapy. Cardiac biomarkers were elevated independent of development of aCMP.

CONCLUSIONS

With high cumulative anthracycline doses, early increase of T2 times 48 h after first treatment with anthracyclines can predict the development of subsequent aCMP after completion of chemotherapy. Early drop of native T1 times occurs irrespective of development of aCMP in high-dose anthracycline therapy.

Native T1 mapping detects both acute clinical rejection and graft dysfunction in pediatric heart transplant patients

BACKGROUND

Cardiovascular magnetic resonance (CMR) is emerging as an important tool for cardiac allograft assessment. Native T1 mapping may add value in identifying rejection and in assessing graft dysfunction and myocardial fibrosis burden. We hypothesized that CMR native T1 values and features of textural analysis of T1 maps would identify acute rejection, and in a secondary analysis, correlate with markers of graft dysfunction, and with fibrosis percentage from endomyocardial biopsy (EMB).

METHODS

Fifty cases with simultaneous EMB, right heart catheterization, and 1.5 T CMR with breath-held T1 mapping via modified Look-Locker inversion recovery (MOLLI) in 8 short-axis slices and subsequent quantification of mean and peak native T1 values, were performed on 24 pediatric subjects. A single mid-ventricular slice was used for image texture analysis using nine gray-level co-occurrence matrix features. Digital quantification of Masson trichrome stained EMB samples established degree of fibrosis. Markers of graft dysfunction, including serum brain natriuretic peptide levels and hemodynamic measurements from echocardiography, catheterization, and CMR were collated. Subjects were divided into three groups based on degree of rejection: acute rejection requiring new therapy, mild rejection requiring increased ongoing therapy, and no rejection with no change in treatment. Statistical analysis included student's t-test and linear regression.

RESULTS

Peak and mean T1 values were significantly associated with acute rejection, with a monotonic trend observed with increased grade of rejection. Texture analysis demonstrated greater spatial heterogeneity in T1 values, as demonstrated by energy, entropy, and variance, in cases requiring treatment. Interestingly, 2 subjects who required increased therapy despite low grade EMB results had abnormal peak T1 values. Peak T1 values also correlated with increased BNP, right-sided filling pressures, and capillary wedge pressures. There was no difference in histopathological fibrosis percentage among the 3 groups; histopathological fibrosis did not correlate with T1 values or markers of graft dysfunction.

CONCLUSION

In pediatric heart transplant patients, native T1 values identify acute rejection requiring treatment and may identify graft dysfunction. CMR shows promise as an important tool for evaluation of cardiac grafts in children, with T1 imaging outperforming biopsy findings in the assessment of rejection.

Reproducibility assessment of a biomechanical model-based elasticity imaging method for identifying changes in left ventricular mechanical stiffness

Purpose

Cardiotoxicity of antineoplastic therapies is increasingly a risk to cancer patients treated with curative intent with years of life to protect. Studies highlight the importance of identifying early cardiac decline in cancer patients undergoing cardiotoxic therapies. Accurate tools to study this are a critical clinical need. Current and emerging methods for assessing cardiotoxicity are too coarse for identifying preclinical cardiac degradation or too cumbersome for clinical implementation.

Approach

In the previous work, we developed a noninvasive biomechanical model-based elasticity imaging methodology (BEIM) to assess mechanical stiffness changes of the left ventricle (LV) based on routine cine cardiac magnetic resonance (CMR) images. We examine this methodology to assess methodological reproducibility. We assessed a cohort of 10 participants that underwent test/retest short-axis CMR imaging at baseline and follow-up sessions as part of a previous publicly available study. We compare test images to retest images acquired within the same session to assess within-session reproducibility. We also compare test and retest images acquired at the baseline imaging session to test and retest images acquired at the follow-up imaging session to assess between-session reproducibility.

Results

We establish the within-session and between-session reproducibility of our method, with global elasticity demonstrating repeatability within a range previously demonstrated in cardiac strain imaging studies. We demonstrate increased repeatability of global elasticity compared to segmental elasticity for both within-session and between-session. Within-subject coefficients of variation for within-session test/retest images globally for all modulus directions and a mechanical fractional mechanical stiffness anisotropy metric ranged from 11% to 28%.

Conclusions

Results suggest that our methodology can reproducibly generate estimates of relative mechanical elasticity of the LV and provides a threshold for distinguishing true changes in myocardial mechanical stiffness from experimental variation. BEIM has applications in identifying preclinical cardiotoxicity in breast cancer patients undergoing antineoplastic therapies.

Cardioprotective Strategies from Cardiotoxicity in Cancer Patients: A Comprehensive Review

Cardiotoxicity is a significant complication of chemotherapeutic agents in cancer patients. Cardiovascular incidents including LV dysfunction, heart failure (HF), severe arrhythmias, arterial hypertension, and death are associated with high morbidity and mortality. Risk stratification of cancer patients prior to initiation of chemotherapy is crucial, especially in high-risk patients for cardiotoxicity. The early identification and management of potential risk factors for cardiovascular side effects seems to contribute to the prevention or minimization of cardiotoxicity. Screening of cancer patients includes biomarkers such as cTnI and natriuretic peptide and imaging measurements such as LV function, global longitudinal strain, and cardiac MRI. Cardioprotective strategies have been investigated over the last two decades. These strategies for either primary or secondary prevention include medical therapy such as ACE inhibitors, ARBs, b-blockers, aldosterone antagonists, statins and dexrazoxane, physical therapy, and reduction of chemotherapeutic dosages. However, data regarding dosages, duration of medical therapy, and potential interactions with chemotherapeutic agents are still limited. Collaboration among oncologists, cardiologists, and cardio-oncologists could establish management cardioprotective strategies and approved follow-up protocols in patients with cancer receiving chemotherapy.

Cardiovascular Magnetic Resonance Imaging in the Early Detection of Cardiotoxicity Induced by Cancer Therapies

The significant progress in cancer treatment, including chemotherapy, immunotherapy, radiotherapy, and combination therapies, has led to higher long-term survival rates in cancer patients, while the cardiotoxicity caused by cancer treatment has become increasingly prominent. Cardiovascular magnetic resonance (CMR) is a non-invasive comprehensive imaging modality that provides not only anatomical information, but also tissue characteristics and cardiometabolic and energetic assessment, leading to its increased use in the early identification of cardiotoxicity, and is of major importance in improving the survival rate of cancer patients. This review focused on CMR techniques, including myocardial strain analysis, T1 mapping, T2 mapping, and extracellular volume fraction (ECV) calculation in the detection of early myocardial injury induced by cancer therapies. We summarized the existing studies and ongoing clinical trials using CMR for the assessment of subclinical ventricular dysfunction and myocardial changes at the tissue level. The main focus was to explore the potential of clinical and preclinical CMR techniques for continuous non-invasive monitoring of myocardial toxicity associated with cancer therapy.

SCMR expert consensus statement for cardiovascular magnetic resonance of acquired and non-structural pediatric heart disease

Cardiovascular magnetic resonance (CMR) is widely used for diagnostic imaging in the pediatric population. In addition to structural congenital heart disease (CHD), for which published guidelines are available, CMR is also performed for non-structural pediatric heart disease, for which guidelines are not available. This article provides guidelines for the performance and reporting of CMR in the pediatric population for non-structural ("non-congenital") heart disease, including cardiomyopathies, myocarditis, Kawasaki disease and systemic vasculitides, cardiac tumors, pericardial disease, pulmonary hypertension, heart transplant, and aortopathies. Given important differences in disease pathophysiology and clinical manifestations as well as unique technical challenges related to body size, heart rate, and sedation needs, these guidelines focus on optimization of the CMR examination in infants and children compared to adults. Disease states are discussed, including the goals of CMR examination, disease-specific protocols, and limitations and pitfalls, as well as newer techniques that remain under development.

Cardiovascular Imaging in Cardio-Oncology: The Role of Echocardiography and Cardiac MRI in Modern Cardio-Oncology

Cardiovascular (CV) events are an increasingly common limitation of effective anticancer therapy. Over the last decade imaging has become essential to patients receiving contemporary cancer therapy. Herein we discuss the current state of CV imaging in cardio-oncology. We also provide a practical apparatus for the use of imaging in everyday cardiovascular care of oncology patients to improve outcomes for those at risk for cardiotoxicity, or with established cardiovascular disease. Finally, we consider future directions in the field given the wave of new anticancer therapies.

Myocardial extracellular volume derived from contrast-enhanced chest computed tomography for longitudinal evaluation of cardiotoxicity in patients with breast cancer treated with anthracyclines

Objectives

To assess the value of myocardial extracellular volume (ECV) derived from contrast-enhanced chest computed tomography (CT) for longitudinal evaluation of cardiotoxicity in patients with breast cancer (BC) treated with anthracycline (AC).

Materials and methods

A total of 1151 patients with BC treated with anthracyclines, who underwent at least baseline, and first follow-up contrast-enhanced chest CT were evaluated. ECV and left ventricular ejection fraction (LVEF) were measured before (ECV₀, LVEF₀), during ((ECV₁, LVEF₁) and (ECV₂, LVEF₂)), and after (ECV₃, LVEF₃) AC treatment. ECV values were evaluated at the middle of left ventricular septum on venous phase images. Cancer therapy-related cardiac dysfunction (CTRCD) was recorded.

Results

Mean baseline LVEF values were 65.85% ± 2.72% and 102 patients developed CTRCD. The mean ECV₀ was 26.76% ± 3.03% (N₀ = 1151). ECV₁, ECV₂, and ECV₃ (median interval: 61 (IQR, 46–75), 180 (IQR, 170–190), 350 (IQR, 341–360) days from baseline) were 31.32% ± 3.10%, 29.60% ± 3.24%, and 32.05% ± 3.58% (N₁ = 1151, N₂ = 841, N₃ = 511). ECV₁, ECV₂, and ECV₃ were significantly higher than ECV₀ (p < 0.001). ECV₀ and ECV₁ showed no difference between CTRCD (+) and CTRCD (−) group (p₁ = 0.150; p₂ = 0.216). However, ECV₂ and ECV₃ showed significant differences between the two groups (p₃ < 0.001; p₄ < 0.001).

Conclusion

CT-derived ECV is a potential biomarker for dynamic monitoring AC cardiotoxicity in patients with BC.

Associations between blood biomarkers, cardiac function and adverse outcome in a young tetralogy of Fallot cohort

BACKGROUND

To determine the potential prognostic value and clinical correlations of blood biomarkers in a cohort of patients with Tetralogy of Fallot (TOF).

METHODS

In the setting of multicenter prospective research studies TOF patients underwent blood sampling, cardiopulmonary exercise testing and low-dose dobutamine stress cardiac magnetic resonance (CMR) imaging. In the blood sample NT-proBNP, GDF-15, Galectin-3, ST-2, DLK-1, FABP4, IGFBP-1, IGFBP-7, MMP-2, and vWF were assessed. During subsequent follow-up, patients were evaluated for reaching the study endpoint (cardiac death, arrhythmia-related hospitalization or cardioversion/ablation, VO₂ max ≤65% of predicted). Regression analysis was used to explore the correlation between blood biomarkers (corrected for age and gender) and other clinical parameters. The potential predictive value of blood biomarkers and events were assessed with Kaplan-Meier analysis and Cox proportional hazard analysis.

RESULTS

We included 137 Fallot patients, median age 19.2 (interquartile range: 14.6-25.7) years, median age at TOF-repair 0.9 (0.5-1.9) years. After a median follow-up of 8.7 (6.3-10.7) years, 20 (14.6%) patients reached the composite endpoint. In a multivariable cox-regression analysis corrected for age at study baseline, elevated IGFBP-7 and MMP-2 levels were associated with the composite endpoint. We also noted a correlation between DLK-1 and relative change in right ventricular end systolic volume during dobutamine stress CMR (β = -0.27, p = 0.010), a correlation between FABP4 and Max VO₂ (β = -0.41, p ≤0.001 and between MMP-2 and tricuspid valve E/A ratio (β = -0.15, p = 0.037).

CONCLUSIONS

IGFBP-7, MMP-2 and DLK-1 levels are related to cardiac function and long-term outcome in TOF patients.

Preventive aerobic training preserves sympathovagal function and improves DNA repair capacity of peripheral blood mononuclear cells in rats with cardiomyopathy

To evaluate the effect of preventive aerobic exercise training on sympathovagal function, cardiac function, and DNA repair capacity in a preclinical model of doxorubicin (DOX)-induced cardiomyopathy. Forty male Wistar-Kyoto rats were allocated into four groups (n = 10/group): D (DOX-treated) and C (controls) remained sedentary, and DT (DOX-trained) and CT (control-trained) performed aerobic training 4 days/week, during 4 weeks before exposure to DOX (4 mg/kg/week during 4 weeks) or saline solution. We evaluated cardiac function (echocardiography), hemodynamic and sympathovagal modulation (artery-femoral cannulation), cardiac troponin T levels, and DNA repair capacity (comet assay). Exercise training preserved ejection fraction (D: − 14.44% vs. DT: − 1.05%, p < 0.001), fractional shortening (D: − 8.96% vs. DT: − 0.27%, p = 0.025) and troponin T levels (D: 6.4 ± 3.6 vs. DT: 2.8 ± 1.7 ng/mL, p = 0.010). DOX increased heart rate variability (C: 27.7 ± 7.9 vs. D: 7.5 ± 2.2 ms², p < 0.001) and induced sympathovagal dysfunction (LF/HF, C: 0.37 ± 0.15 vs. D: 0.15 ± 0.15, p = 0.036) through exacerbation of sympathetic function (LF, C: 0.22 ± 0.01 vs. D: 0.48 ± 0.24 Hz, p = 0.019). Peripheral mononuclear blood cells of DT animals presented lower residual DNA damage (D: 43.4 ± 8.4% vs. DT: 26 ± 3.4%, p = 0.003 after 1 h). Cardioprotective effects of preventive aerobic exercise training are mediated by preservation of sympathovagal function and improvement of DNA repair capacity of peripheral blood mononuclear cells.

Detection of doxorubicin-induced cardiotoxicity using myocardial T1 and T2 relaxation times in childhood acute lymphoblastic leukemia survivors

Doxorubicin leads to dose-dependent cardiotoxicity in childhood acute lymphoblastic leukemia (ALL) survivors. The first aim was to propose a contour-based estimation of T1 and T2 relaxation times based on the myocardial area, while our second aim was to evaluate native T1, post-gadolinium T1 and T2 relaxation time sensitivity to detect myocardial changes. A total of 84 childhood ALL survivors were stratified in regard to their prognostic risk groups: standard risk (SR), n = 20), high-risk with and without dexrazoxane (HR + DEX, n = 39 and HR, n = 25). Survivors' mean age was of 22.0 ± 6.9 years, with a mean age at cancer diagnosis of 8.0 ± 5.2 years. CMR acquisitions were performed on a 3 T MRI system and included an ECG-gated 3(3)3(3)5 MOLLI sequence for T1 mapping and an ECG-gated T2-prepared TrueFISP sequence for T2 mapping. Myocardial contours were semi-automatically segmented using an interactive implementation of cubic Bezier curves. We found excellent repeatability between operators for native T1 (ICC = 0.91), and good repeatability between operators for post-gadolinium T1 (ICC = 0.84) and T2 (ICC = 0.79). Bland and Altman tests demonstrated a strong agreement between our contour-based method and images analyzed using the CVI42 software on the measure of native T1, post-gadolinium T1, and T2. No significant differences between survivors' prognostic risk groups in native T1 were reported, while we observed significant differences between survivors' prognostic risk groups in post-gadolinium T1 and T2. Significant differences were observed between male and female survivors. Differences between groups were also observed in partition coefficients, but no significant differences were observed between male and female survivors. The use of CMR parameters with native T1, post-gadolinium T1, and T2 allowed to show that survivors at a high-risk prognostic were more exposed to doxorubicin-related cardiotoxicity than those who were at a standard risk prognostic or who received dexrazoxane treatments.

Divergent Cardiac Effects of Angiotensin II and Isoproterenol Following Juvenile Exposure to Doxorubicin

Hypertension is the most significant risk factor for heart failure in doxorubicin (DOX)-treated childhood cancer survivors. We previously developed a two-hit mouse model of juvenile DOX-induced latent cardiotoxicity that is exacerbated by adult-onset angiotensin II (ANGII)-induced hypertension. It is still not known how juvenile DOX-induced latent cardiotoxicity would predispose the heart to pathologic stimuli that do not cause hypertension. Our main objective is to determine the cardiac effects of ANGII (a hypertensive pathologic stimulus) and isoproterenol (ISO, a non-hypertensive pathologic stimulus) in adult mice pre-exposed to DOX as juveniles. Five-week-old male C57BL/6N mice were administered DOX (4 mg/kg/week) or saline for 3 weeks and then allowed to recover for 5 weeks. Thereafter, mice were administered either ANGII (1.4 mg/kg/day) or ISO (10 mg/kg/day) for 14 days. Juvenile exposure to DOX abrogated the hypertrophic response to both ANGII and ISO, while it failed to correct ANGII- and ISO-induced upregulation in the hypertrophic markers, ANP and BNP. ANGII, but not ISO, worsened cardiac function and exacerbated cardiac fibrosis in DOX-exposed mice as measured by echocardiography and histopathology, respectively. The adverse cardiac remodeling in the DOX/ANGII group was associated with a marked upregulation in several inflammatory and fibrotic markers and altered expression of Ace, a critical enzyme in the RAAS. In conclusion, juvenile exposure to DOX causes latent cardiotoxicity that predisposes the heart to a hypertensive pathologic stimulus (ANGII) more than a non-hypertensive stimulus (ISO), mirroring the clinical scenario of worse cardiovascular outcome in hypertensive childhood cancer survivors.

Myocardial Extracellular Volume Fraction Measured by Cardiac Magnetic Resonance Imaging Negatively Correlates With Cardiomyocyte Breadth in a Healthy Porcine Model

Background

The extracellular volume fraction (ECV) derived from cardiac magnetic resonance imaging (MRI) is extensively used to evaluate myocardial fibrosis. However, due to the limited histological verification in healthy individuals, it remains unclear whether the size of cardiomyocytes may play a potential role in the physiological changes of ECV. The aim of this study was to examine the association between cardiomyocyte size and myocardial ECV by using a healthy porcine model.

Methods

Sixteen domestic healthy pigs were anesthetized and underwent cardiac MRI with mechanical controlled breathing. Intravenous contrast medium was introduced at a dose of 0.2–0.25 mmol/kg. The interventricular septum ECV was calculated using an established MRI procedure, which was based on the pre- and post-contrast T1 values of the heart and individual blood hematocrit. The cardiomyocyte breadth (CmyB) in cross section was measured by hematoxylin and eosin staining to reflect the cardiomyocyte size.

Results

Data were successfully acquired from 14 pigs. The CmyB was obtained from the myocardial tissues corresponding to the region of interest on cardiac MRI. The mean ± SD of the ECV was 0.253 ± 0.043, and the mean ± SD of the CmyB was 10.02 ± 0.84 μm. The ECV exhibited a negative correlation with the CmyB (r = −0.729, p = 0.003).

Conclusion

The myocardial ECV detected by cardiac MRI is negatively correlated with the CmyB in healthy pigs, demonstrating that the size of cardiomyocytes is potentially associated with the ECV under physiological conditions.

Case Series: Recovery of Chemotherapy-Related Acute Heart Failure by the Combined Use of Sacubitril Valsartan and Wearable Cardioverter Defibrillator: A Novel Winning Combination in Cardio-Oncology

Effective anticancer treatments have dramatically improved the outcome of patients with cancer, but cardiac toxicity reduces their clinical efficacy in a non-negligible percentage of patients. Sacubitril/valsartan is a new paradigm in the treatment of chronic heart failure, with a reduced ejection fraction due to the enhancement of natriuretic peptides' properties when coupled with a blocking effect on the angiotensin II type 1 (AT1) receptors. As with other clinical conditions of heart failure with potentially reversible declines in cardiac function, a wearable cardioverter defibrillator (WCD) is a valid tool for protection against sudden death until recovery occurs. We report a case series of four patients with chemotherapy-related acute cardiac failure with severely reduced cardiac function. They were successfully treated with sacubitril/valsartan while being protected from malignant arrhythmias using a wearable cardioverter defibrillator until the recovery of cardiac function. Sacubitril/valsartan was confirmed to be effective in anthracycline-related cardiac toxicity and the wearable cardioverter defibrillator should be considered as a support tool even in the oncology patient.

Herceptin-Mediated Cardiotoxicity: Assessment by Cardiovascular Magnetic Resonance

Herceptin (trastuzumab) is a recombinant, humanized, monoclonal antibody that targets the human epidermal growth factor receptor 2 (HER2) and is used in the treatment of HER2-positive breast and gastric cancers. However, it carries a risk of cardiotoxicity, manifesting as left ventricular (LV) systolic dysfunction, conventionally assessed for by transthoracic echocardiography. Clinical surveillance of cardiac function and discontinuation of trastuzumab at an early stage of LV systolic dysfunction allow for the timely initiation of heart failure drug therapies that can result in the rapid recovery of cardiac function in most patients. Often considered the reference standard for the noninvasive assessment of cardiac volume and function, cardiac magnetic resonance (CMR) imaging has superior reproducibility and accuracy compared to other noninvasive imaging modalities. However, due to limited availability, it is not routinely used in the serial assessment of cardiac function in patients receiving trastuzumab. In this article, we review the diagnostic and prognostic role of CMR in trastuzumab-mediated cardiotoxicity.

Cardiomyocyte Atrophy, an Underestimated Contributor in Doxorubicin-Induced Cardiotoxicity

Left ventricular (LV) mass loss is prevalent in doxorubicin (DOX)-induced cardiotoxicity and is responsible for the progressive decline of cardiac function. Comparing with the well-studied role of cell death, the part of cardiomyocyte atrophy (CMA) playing in the LV mass loss is underestimated and the knowledge of the underlying mechanism is still limited. In this review, we summarized the recent advances in the DOX-induced CMA. We found that the CMA caused by DOX is associated with the upregulation of FOXOs and “atrogenes,” the activation of transient receptor potential canonical 3-NADPH oxidase 2 (TRPC3-Nox2) axis, and the suppression of IGF-1-PI3K signaling pathway. The imbalance of anabolic and catabolic process may be the common final pathway of these mechanisms. At last, we provided some strategies that have been demonstrated to alleviate the DOX-induced CMA in animal models.

Myocardial Deformation Imaging by Speckle Tracking Echocardiography for Assessment of Cardiotoxicity in Children During and After Chemotherapy: A Systematic Review and Meta-analysis

BACKGROUND

Childhood cancer patients and childhood cancer survivors (CCS) are at risk of developing chemotherapy-induced cardiomyopathy. Myocardial deformation imaging has shown potential in the early detection of subclinical myocardial damage with implications on therapeutic interventions and improvement of outcomes. We aimed to perform a systemic review and meta-analysis of literature on the assessment of left (LV) and right ventricular (RV) myocardial deformation by speckle tracking echocardiography (STE) at rest and during stress in childhood cancer patients during and in survivors after chemotherapy.

METHODS

A systematic review was performed through searching MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Controlled Trials, and Scopus. Search hedges were created to cover the concepts of childhood cancer, chemotherapy, radiotherapy, anthracycline, cardiotoxicity, speckle tracking, myocardial strain, and myocardial deformation. Two independent investigators reviewed the eligibility of the articles for inclusion. Weighted mean difference in ventricular strain between pre-and post-chemotherapy treatment and that between long-term CCS and healthy subjects were estimated by random-effect models with 95% confidence intervals. Heterogeneity and publication bias were assessed by I2 statistics and Egger test, respectively.

RESULTS

Of the total of 8703 records initially identified, 42 studies with a total of 430 childhood cancer patients were included. Of these 42 studies that showed heterogeneities, 9 assessed early myocardial injury during chemotherapy, 30 assessed late myocardial injury after chemotherapy with no publication bias, and 3 studied myocardial mechanics during stress. The main findings were 1) impairment of LV systolic deformation in childhood cancer patients during the initial treatment phase and among long-term CCS, while data on changes in RV deformation are limited and inconclusive, 2) the predictive value of early reduction of myocardial strain imaging in forecasting subsequent development of cardiotoxicity is unknown as it has not been studied, 3) limited data suggest possibility of impaired LV contractile mechanics during stress in CCS, and 4) cumulative anthracycline dose and chest-directed radiotherapy are consistently identified as factors associated with impaired myocardial deformation.results CONCLUSIONS: Myocardial strain imaging by STE unveils early evidence of myocardial injury in childhood cancer patients and long-term CCS. To support its adoption for clinical use, more data are required for the better understating of myocardial deformation parameters in the risk stratification of childhood cancer patients and prediction of development of cardiomyopathy among CCS.

Juvenile exposure to doxorubicin alters the cardiovascular response to adult-onset psychosocial stress in mice

Childhood cancer survivors have a high risk for premature cardiovascular diseases, mainly due to cardiotoxic cancer treatments such as doxorubicin (DOX). Psychosocial stress is a significant cardiovascular risk factor and an enormous burden in childhood cancer survivors. Although observational studies suggest that psychosocial stress is associated with cardiovascular complications in cancer survivors, there is no translationally relevant animal model to study this interaction. We established a "two-hit" model in which juvenile mice were administered DOX (4 mg/kg/week for 3 weeks), paired to a validated model of chronic subordination stress (CSS) 5 weeks later upon reaching adulthood. Blood pressure, heart rate, and activity were monitored by radio-telemetry. At the end of CSS experiment, cardiac function was assessed by echocardiography. Cardiac fibrosis and inflammation were assessed by histopathologic analysis. Gene expressions of inflammatory and fibrotic markers were determined by PCR. Juvenile exposure to DOX followed by adult-onset CSS caused cardiac fibrosis and inflammation as evident by histopathologic findings and upregulated gene expression of multiple inflammatory and fibrotic markers. Intriguingly, juvenile exposure to DOX blunted CSS-induced hypertension but not CSS-induced tachycardia. There were no significant differences in cardiac function parameters among all groups, but juvenile exposure to DOX abrogated the hypertrophic response to CSS. In conclusion, we established a translationally relevant mouse model of juvenile DOX-induced cardiotoxicity that predisposes to adult-onset stress-induced adverse cardiac remodeling. Psychosocial stress should be taken into consideration in cardiovascular risk stratification of DOX-treated childhood cancer survivors.

A Contemporary Review of the Effects of Exercise Training on Cardiac Structure and Function and Cardiovascular Risk Profile: Insights From Imaging

Exercise is a commonly prescribed therapy for patients with established cardiovascular disease or those at high risk for de novo disease. Exercise-based, multidisciplinary programs have been associated with improved clinical outcomes post myocardial infarction and is now recommended for patients with cancer at elevated risk for cardiovascular complications. Imaging studies have documented numerous beneficial effects of exercise on cardiac structure and function, vascular function and more recently on the cardiovascular risk profile. In this contemporary review, we will discuss the effects of exercise training on imaging-derived cardiovascular outcomes. For cardiac imaging via echocardiography or magnetic resonance, we will review the effects of exercise on left ventricular function and remodeling in patients with established or at risk for cardiac disease (myocardial infarction, heart failure, cancer survivors), and the potential utility of exercise stress to assess cardiac reserve. Exercise training also has salient effects on vascular function and health including the attenuation of age-associated arterial stiffness and thickening as assessed by Doppler ultrasound. Finally, we will review recent data on the relationship between exercise training and regional adipose tissue deposition, an emerging marker of cardiovascular risk. Imaging provides comprehensive and accurate quantification of cardiac, vascular and cardiometabolic health, and may allow refinement of risk stratification in select patient populations. Future studies are needed to evaluate the clinical utility of novel imaging metrics following exercise training.

Detection of Subclinical Cardiovascular Disease by Cardiovascular Magnetic Resonance in Lymphoma Survivors

BACKGROUND

Long-term survivors of Hodgkin lymphoma (HL) and mediastinal non-Hodgkin lymphoma experience late adverse effects of radiotherapy and/or anthracycline-containing chemotherapy, leading to premature cardiovascular morbidity and mortality.

OBJECTIVES

The aim of this study was to identify markers for subclinical cardiovascular disease using cardiovascular magnetic resonance (CMR) in survivors of HL and non-Hodgkin lymphoma.

METHODS

CMR was performed in 80 lymphoma survivors treated with mediastinal radiotherapy with or without anthracyclines, and results were compared with those among 40 healthy control subjects matched for age and sex.

RESULTS

Of the 80 lymphoma survivors, 98% had histories of HL, the mean age was 47 ± 11 years, and 54% were male. Median radiotherapy dose was 36 Gy (interquartile range: 36-40 Gy), and radiotherapy was combined with anthracyclines in 70 lymphoma survivors (88%). Mean time between diagnosis and CMR was 20 ± 8 years. Significantly lower left ventricular (LV) ejection fraction (53% ± 5% vs 60% ± 5%; P < 0.001) and LV mass (47 ± 10 g/m2 vs 56 ± 8 g/m2; P < 0.001) and higher LV end-systolic volume (37 ± 8 mL/m2 vs 33 ± 7 mL/m2; P = 0.013) were found in lymphoma survivors. LV global strain parameters were also significantly worse in lymphoma survivors (P < 0.02 for all). Native myocardial T1 was significantly higher in lymphoma survivors compared with healthy control subjects (980 ± 33 ms vs 964 ± 25 ms; P = 0.007), and late gadolinium enhancement was present in 11% of the survivors.

CONCLUSIONS

Long-term lymphoma survivors have detectable changes in LV function and native myocardial T1 on CMR. Further longitudinal studies are needed to assess the implication of these changes in relation to treatment and clinical outcome.

Cardiovascular magnetic resonance characterisation of anthracycline cardiotoxicity in adults with normal left ventricular ejection fraction

BACKGROUND

Anthracycline therapy may lead to changes in cardiac structure and function not detectable by solely evaluating left ventricular ejection fraction (LVEF).

OBJECTIVES

We hypothesized that cardiovascular magnetic resonance (CMR) would identify structural and functional myocardial abnormalities in anthracycline-treated cancer survivors with normal LVEF, compared to a matched control population.

METHODS

Forty-five cancer survivors (56 ± 16 yrs., 60% female) with normal LVEF (59.5 ± 4.1%) were studied a median of 11 months (range 3-36) following administration of 237 ± 83 mg/m² anthracycline, and compared with forty-five healthy control subjects of similar age and sex (53 ± 16 yrs., 60% female) with normal LVEF (60.8 ± 2.4%) using 1.5 T CMR.

RESULTS

Significantly smaller indexed left ventricular mass (45.6 ± 8.7 vs 50.3 ± 10.1 g/m², p = 0.02) and indexed myocardial cell volume (30.5 ± 5.7 vs 34.8 ± 7.2 ml/m², p = 0.002) were evident in cancer survivors and the latter was inversely associated with cumulative anthracycline dose (r = -0.31, p = 0.02). Surrogate CMR markers of myocardial fibrosis were significantly increased in cancer survivors (native myocardial T₁: 1021 ± 40 vs 996 ± 35 ms, p = 0.002; extracellular volume: 29.5 ± 4.5 vs 27.4 ± 2.3%, p = 0.006). CMR-derived feature-tracking global longitudinal strain (GLS) was significantly impaired in cancer survivors (2D GLS -18.3 ± 2.6 vs -20.0 ± 2.0%, p < 0.001; 3D GLS -14.5 ± 2.3 vs -16.4 ± 2.6%, p < 0.001). Parameters exhibited good to excellent (ICC = 0.86-0.98) inter- and intra-observer reproducibility.

CONCLUSIONS

Anthracycline-treated cancer survivors with normal LVEF have significant perturbations of LV mass, myocardial cell volume, native myocardial T1, ECV, CMR-derived 2D and 3D GLS, compared to controls, with good to excellent levels of inter- and intra-observer reproducibility.

Developing a biomechanical model-based elasticity imaging method for assessing hormone receptor positive breast cancer treatment-related myocardial stiffness changes

Purpose: Assessing cardiotoxicity as a result of breast cancer therapeutics is increasingly important as breast cancer diagnoses are trending younger and overall survival is increasing. With evidence showing that prevention of cardiotoxicity plays a significant role in increasing overall survival, there is an unmet need for accurate non-invasive methods to assess cardiac injury due to cancer therapies. Current clinical methods are too coarse and emerging research methods have not yet achieved clinical implementation. Approach: As a proof of concept, we examine myocardial elasticity imaging in the setting of premenopausal women diagnosed with hormone receptor positive (HR-positive) breast cancer undergoing severe estrogen depletion, as cardiovascular injury from early estrogen depletion is well-established. We evaluate the ability of our model-based cardiac elasticity imaging analysis method to indicate subclinical cancer therapy-related cardiac decline by examining differences in the change in cardiac elasticity over time in two cohorts of premenopausal women either undergoing severe estrogen depletion for HR-positive breast cancer or triple negative breast cancer patients as comparators. Results: Our method was capable of producing functional mechanical elasticity maps of the left ventricle (LV). Using these elasticity maps, we show significant differences in cardiac mechanical elasticity in the HR-positive breast cancer cohort compared to the comparator cohort. Conclusions: We present our methodology to assess the mechanical stiffness of the LV by interrogating cardiac magnetic resonance images within a computational biomechanical model. Our preliminary study suggests the potential of this method for examining cardiac tissue mechanical stiffness properties as an early indicator of cardiac decline.

Irisin ameliorates doxorubicin-induced cardiac perivascular fibrosis through inhibiting endothelial-to-mesenchymal transition by regulating ROS accumulation and autophagy disorder in endothelial cells

The dose-dependent toxicity to cardiomyocytes has been well recognized as a central characteristic of doxorubicin (DOX)-induced cardiotoxicity (DIC), however, the pathogenesis of DIC in the cardiac microenvironment remains elusive. Irisin is a new hormone-like myokine released into the circulation in response to exercise with distinct functions in regulating apoptosis, inflammation, and oxidative stress. Recent advances revealed the role of irisin as a novel therapeutic method and an important mediator of the beneficial effects of exercise in cardioprotection. Here, by using a low-dose long-term mouse DIC model, we found that the perivascular fibrosis was involved in its myocardial toxicity with the underlying mechanism of endothelial-to-mesenchymal transition (EndMT). Irisin treatment could partially reverse DOX-induced perivascular fibrosis and cardiotoxicity compared to endurance exercise. Mechanistically, DOX stimulation led to excessive accumulation of ROS, which activated the NF-κB-Snail pathway and resulted in EndMT. Besides, dysregulation of autophagy was also found in DOX-treated endothelial cells. Restoring autophagy flux could ameliorate EndMT and eliminate ROS. Irisin treatment significantly alleviated ROS accumulation, autophagy disorder, NF-κB-Snail pathway activation as well as the phenotype of EndMT by targeting uncoupling protein 2 (UCP2). Our results also initially found that irisin was mainly secreted by cardiomyocytes in the cardiac microenvironment, which was significantly reduced by DOX intervention, and had a protective effect on endothelial cells in a paracrine manner. In summary, our study indicated that DOX-induced ROS accumulation and autophagy disorders caused an EndMT in CMECs, which played a role in the perivascular fibrosis of DIC. Irisin treatment could partially reverse this phenomenon by regulating UCP2. Cardiomyocytes were the main source of irisin in the cardiac microenvironment. The current study provides a novel perspective elucidating the pathogenesis and the potential treatment of DIC.

The Utility of Advanced Cardiovascular Imaging in Cancer Patients-When, Why, How, and the Latest Developments

Cardio-oncology encompasses the risk stratification, prognostication, identification and management of cancer therapeutics related cardiac dysfunction (CTRCD). Cardiovascular imaging (CVI) plays a significant role in each of these scenarios and has broadened from predominantly quantifying left ventricular function (specifically ejection fraction) to the identification of earlier bio-signatures of CTRCD. Recent data also demonstrate the impact of chemotherapy on the right ventricle, left atrium and pericardium and highlight a possible role for CVI in the identification of CTRCD through tissue characterization and assessment of these cardiac chambers. This review aims to provide a contemporary perspective on the role of multi-modal advanced cardiac imaging in cardio-oncology.

Left ventricular dyssynchrony in long-term childhood cancer survivors treated with anthracyclines: a retrospective cross-sectional study

The purpose of this study was to investigate left ventricular contraction patterns in asymptomatic Childhood cancer survivors (CCS) using two-dimensional speckle tracking echocardiography (2DSTE). Left ventricular longitudinal and circumferential myocardial parameters were assessed using 2DSTE, in asymptomatic CCS and age matched healthy controls. Time to peak (T2P) systolic strain was quantified. Dyssynchrony index (DI) was measured by calculating the standard deviation of T2P systolic strain of six segments in each view. Difference between T2P systolic longitudinal strain of septal and lateral wall was also assessed as a parameter for dyssynchrony. We included 115 CCS with a median age of 17.2 years (range 5.6–39.5) and a median follow up of 11.3 years (range 4.9–29.5) and 119 controls. Conventional echocardiographic parameters and global longitudinal strain were significantly decreased in CCS compared to controls (p < 0.01 and p = 0.02, respectively). Dyssynchrony index did not differ between CCS and controls. There was a clinically insignificant smaller absolute difference between T2P systolic longitudinal of septal and lateral wall in CCS compared to controls. We showed no difference in longitudinal or circumferential left ventricular dyssynchrony in CCS compared to controls using 2DSTE. Future research should focus on assessing dyssynchrony in more segments and a larger CCS population, using both 2D and 3DSTE.

Oxidative stress and inflammation: determinants of anthracycline cardiotoxicity and possible therapeutic targets

Chemotherapy with anthracycline-based regimens remains a cornerstone of treatment of many solid and blood tumors but is associated with a significant risk of cardiotoxicity, which can manifest as asymptomatic left ventricular dysfunction or overt heart failure. These effects are typically dose-dependent and cumulative and may require appropriate screening strategies and cardioprotective therapies in order to minimize changes to anticancer regimens or even their discontinuation. Our current understanding of cardiac damage by anthracyclines includes a central role of oxidative stress and inflammation. The identification of these processes through circulating biomarkers or imaging techniques might then be helpful for early diagnosis and risk stratification. Furthermore, therapeutic strategies relieving oxidative stress and inflammation hold promise to prevent heart failure development or at least to mitigate cardiac damage, although further evidence is needed on their efficacy, either alone or as part of combination therapies with neurohormonal antagonists, which are the current adopted standard.

Ultrahigh-field cardiovascular magnetic resonance T1 and T2 mapping for the assessment of anthracycline-induced cardiotoxicity in rat models: validation against histopathologic changes

BACKGROUND

Chemotherapy-induced cardiotoxicity is a well-recognized adverse effect of chemotherapy. Quantitative T1-mapping cardiovascular magnetic resonance (CMR) is useful for detecting subclinical myocardial changes in anthracycline-induced cardiotoxicity. The aim of the present study was to histopathologically validate the T1 and T2 mapping parameters for the evaluation of diffuse myocardial changes in rat models of cardiotoxicity.

METHODS

Rat models of cardiotoxicity were generated by injecting rats with doxorubicin (1 mg/kg, twice a week). CMR was performed with a 9.4 T ultrahigh-field scanner using cine, pre-T1, post-T1 and T2 mapping sequences to evaluate the left ventricular ejection fraction (LVEF), native T1, T2, and extracellular volume fraction (ECV). Histopathological examinations were performed and the association of histopathological changes with CMR parameters was assessed.

RESULTS

Five control rats and 36 doxorubicin-treated rats were included and classified into treatment periods. In the doxorubicin-treated rats, the LVEF significantly decreased after 12 weeks of treatment (control vs. 12-week treated: 73 ± 4% vs. 59 ± 9%, P = 0.01).  Increased native T1 and ECV were observed after 6 weeks of treatment (control vs. 6-week treated: 1148 ± 58 ms, 14.3 ± 1% vs. 1320 ± 56 ms, 20.3 ± 3%; P = 0.005, < 0.05, respectively). T2 values also increased by six weeks of treatment (control vs. 6-week treated: 16.3 ± 2 ms vs. 10.3 ± 1 ms, P < 0.05). The main histopathological features were myocardial injury, interstitial fibrosis, inflammation, and edema. The mean vacuolar change (%), fibrosis (%), and inflammation score were significantly higher in 6-week treated rats than in the controls (P = 0.03, 0.03, 0.02, respectively). In the univariable analysis, vacuolar change showed the highest correlation with native T1 value (R = 0.60, P < 0.001), and fibrosis showed the highest correlation with ECV value (R = 0.78, P < 0.001). In the multiple linear regression analysis model, vacuolar change was a significant factor for change in native T1 (P = 0.01), and vacuolar change and fibrosis were significant factors for change in ECV (P = 0.006, P < 0.001, respectively) by adding other histopathological parameters (i.e., inflammation and edema scores) CONCLUSIONS: Quantitative T1 and T2 mapping CMR is a useful non-invasive tool reflecting subclinical histopathological changes in anthracycline-induced cardiotoxicity.

Molecular mechanisms of anthracycline cardiovascular toxicity

Anthracyclines are effective chemotherapeutic agents, commonly used in the treatment of a variety of hematologic malignancies and solid tumors. However, their use is associated with a significant risk of cardiovascular toxicities and may result in cardiomyopathy and heart failure. Cardiomyocyte toxicity occurs via multiple molecular mechanisms, including topoisomerase II-mediated DNA double-strand breaks and reactive oxygen species (ROS) formation via effects on the mitochondrial electron transport chain, NADPH oxidases (NOXs), and nitric oxide synthases (NOSs). Excess ROS may cause mitochondrial dysfunction, endoplasmic reticulum stress, calcium release, and DNA damage, which may result in cardiomyocyte dysfunction or cell death. These pathophysiologic mechanisms cause tissue-level manifestations, including characteristic histopathologic changes (myocyte vacuolization, myofibrillar loss, and cell death), atrophy and fibrosis, and organ-level manifestations including cardiac contractile dysfunction and vascular dysfunction. In addition, these mechanisms are relevant to current and emerging strategies to diagnose, prevent, and treat anthracycline-induced cardiomyopathy. This review details the established and emerging data regarding the molecular mechanisms of anthracycline-induced cardiovascular toxicity.

Cardiovascular magnetic resonance in women with cardiovascular disease: position statement from the Society for Cardiovascular Magnetic Resonance (SCMR)

This document is a position statement from the Society for Cardiovascular Magnetic Resonance (SCMR) on recommendations for clinical utilization of cardiovascular magnetic resonance (CMR) in women with cardiovascular disease. The document was prepared by the SCMR Consensus Group on CMR Imaging for Female Patients with Cardiovascular Disease and endorsed by the SCMR Publications Committee and SCMR Executive Committee. The goals of this document are to (1) guide the informed selection of cardiovascular imaging methods, (2) inform clinical decision-making, (3) educate stakeholders on the advantages of CMR in specific clinical scenarios, and (4) empower patients with clinical evidence to participate in their clinical care. The statements of clinical utility presented in the current document pertain to the following clinical scenarios: acute coronary syndrome, stable ischemic heart disease, peripartum cardiomyopathy, cancer therapy-related cardiac dysfunction, aortic syndrome and congenital heart disease in pregnancy, bicuspid aortic valve and aortopathies, systemic rheumatic diseases and collagen vascular disorders, and cardiomyopathy-causing mutations. The authors cite published evidence when available and provide expert consensus otherwise. Most of the evidence available pertains to translational studies involving subjects of both sexes. However, the authors have prioritized review of data obtained from female patients, and direct comparison of CMR between women and men. This position statement does not consider CMR accessibility or availability of local expertise, but instead highlights the optimal utilization of CMR in women with known or suspected cardiovascular disease. Finally, the ultimate goal of this position statement is to improve the health of female patients with cardiovascular disease by providing specific recommendations on the use of CMR.

The cardiovascular determinants of physical function in patients with end-stage kidney disease on haemodialysis

Patients with end-stage kidney disease (ESKD) are often sedentary and decreased functional capacity associates with mortality. The relationship between cardiovascular disease (CVD) and physical function has not been fully explored. Understanding the relationships between prognostically relevant measures of CVD and physical function may offer insight into how exercise interventions might target specific elements of CVD. 130 patients on haemodialysis (mean age 57 ± 15 years, 73% male, dialysis vintage 1.3 years (0.5, 3.4), recruited to the CYCLE-HD trial (ISRCTN11299707), underwent cardiovascular phenotyping with cardiac MRI (left ventricular (LV) structure and function, pulse wave velocity (PWV) and native T1 mapping) and cardiac biomarker assessment. Participants completed the incremental shuttle walk test (ISWT) and sit-to-stand 60 (STS60) as field-tests of physical function. Linear regression models identified CV determinants of physical function measures, adjusted for age, gender, BMI, diabetes, ethnicity and systolic blood pressure. Troponin I, PWV and global native T1 were univariate determinants of ISWT and STS60 performance. NT pro-BNP was a univariate determinant of ISWT performance. In multivariate models, NT pro-BNP and global native T1 were independent determinants of ISWT and STS60 performance. LV ejection fraction was an independent determinant of ISWT distance. However, age and diabetes had the strongest relationships with physical function. In conclusion, NT pro-BNP, global native T1 and LV ejection fraction were independent CV determinants of physical function. However, age and diabetes had the greatest independent influence. Targeting diabetic care may ameliorate deconditioning in these patients and a multimorbidity approach should be considered when developing exercise interventions.

Effect of anthracycline therapy on myocardial function and markers of fibrotic remodelling in childhood cancer survivors

AIMS

Anthracyclines are a cornerstone of paediatric cancer treatment. We aimed to quantify myocardial cardiac magnetic resonance (CMR) native T1 (NT1) and extracellular volume fraction (ECV) as markers of fibrosis in a cohort of childhood cancer survivors (CCS).

METHODS AND RESULTS

A cohort of CCS in remission underwent CMR T1 mapping. Diastolic function was assessed by echocardiography. Results were compared to a cohort of normal controls of similar age and gender. Fifty-five CCS and 46 controls were included. Both groups had similar mean left ventricular (LV) NT1 values (999 ± 36 vs. 1007 ± 32 ms, P = 0.27); ECV was higher (25.6 ± 6.9 vs. 20.7 ± 2.4%, P = 0.003) and intracellular mass was lower (37.5 ± 8.4 vs. 43.3 ± 9.9g/m2, P = 0.02) in CCS. The CCS group had lower LV ejection fraction (EF) and LV mass index with otherwise normal diastolic function in all but one patient. The proportion of subjects with elevated ECV compared to controls did not differ between subgroups with normal or reduced LV EF (22% vs. 28%; P = 0.13) and no correlations were found between LVEF and ECV. While average values remained within normal range, mitral E/E' (6.6 ± 1.6 vs. 5.9 ± 0.9, P = 0.02) was higher in CCS. Neither NT1 nor ECV correlated with diastolic function indices or cumulative anthracycline dose.

CONCLUSIONS

There is evidence for mild diffuse extracellular volume expansion in some asymptomatic CCS; myocyte loss could be part of the mechanism, accompanied by subtle changes in systolic and diastolic function. These findings suggest mild myocardial damage and remodelling after anthracycline treatment in some CCS which requires continued monitoring.