Myocarditis in the Setting of Cancer Therapeutics: Proposed Case Definitions for Emerging Clinical Syndromes in Cardio-Oncology

Cardiovascular adverse events associated with immune checkpoint inhibitors: A retrospective multicenter cohort study

BACKGROUND

Over the past decade, immune checkpoint inhibitors (ICIs) have significantly transformed cancer treatment. However, ICIs inevitably may cause a spectrum of immune-related adverse events, among which cardiovascular toxicity, particularly myocarditis, while infrequent, has garnered increasing attention due to its high fatality rate.

METHODS

We conducted a multicenter retrospective study to characterize ICI-associated cardiovascular adverse events. Logistic regression was performed to explore the risk factors for the development of myocarditis and severe myocarditis. Receiver operating characteristic curves were conducted to assess the diagnostic abilities of cardiac biomarkers to distinguish different cardiovascular toxicities, and the performance and calibration were evaluated using Hosmer-Lemeshow test.

RESULTS

Forty-four patients were identified, including thirty-five myocarditis, five heart failure, three arrhythmias, and one myocardial infarction. Compared with other patients, myocarditis patients had higher cardiac troponin-I (cTnI) levels (p < 0.001), higher creatine kinase levels (p = 0.003), higher creatine kinase isoenzyme-MB (CK-MB) levels (p = 0.013), and shorter time to the incidence of adverse cardiovascular events (p = 0.022) after ICI treatment. Twenty-one patients (60%) were classified as severe myocarditis, and they presented higher cardiac troponin I (cTnI) levels (p = 0.013), higher N-terminal pro-B-type natriuretic peptide levels (p = 0.031), higher creatine kinase levels (p = 0.018), higher CK-MB levels (p = 0.026), and higher neutrophil to lymphocyte ratio (NLR) levels (p = 0.016) compared to non-severe myocarditis patients after ICI treatment. Multivariate logistic regression showed that CK-MB (adjusted odds ratio [OR]: 1.775, 95% confidence interval [CI]: 1.055-2.984, p = 0.031) was the independent risk factor of the development of ICI-associated myocarditis, and cTnI (adjusted OR: 1.021, 95% CI: 1.002-1.039, p = 0.03) and NLR (adjusted OR: 1.890, 95% CI: 1.026-3.483, p = 0.041) were the independent risk factors of ICI-associated severe myocarditis. The receiver operating characteristic curve showed an area under curve of 0.785 (95% CI: 0.642 to 0.928, p = 0.013) for CK-MB, 0.765 (95% CI: 0.601 to 0.929, p = 0.013) for cTnI, and 0.773 for NLR (95% CI: 0.597 to 0.948, p = 0.016).

CONCLUSIONS

Elevated CK-MB after ICI treatment is the independent risk factor for the incidence of ICI-associated myocarditis, and elevated cTnI and NLR after ICI treatment are the independent risk factors for the development of ICI-associated severe myocarditis. CK-MB, cTnI, and NLR demonstrated a promising predictive utility for the identification of ICI-associated myocarditis and severe myocarditis.

Immune Checkpoint Inhibitor-induced Myositis

Myositis induced by immune checkpoint inhibitors (ICIs) is an infrequent, potentially fatal, immune-related adverse event. It has higher incidence in patients who receive combination ICI therapy compared to monotherapy. Patients can present with clinical manifestation symptoms of myositis alone or in combination with myocarditis and/or myasthenia gravis, which significantly worsens the course and prognosis. Diagnosis can generally be made on the basis of clinical presentation, elevation of muscle enzymes, and electromyographic changes, but some patients may require a muscle biopsy. The first line of therapy is high-dose corticosteroids, followed by immunosuppression, plasmapheresis, or intravenous immunoglobulin in patients with severe disease.

Evaluation the Effect of Anthracyclines on Cardiac Function in Children Lymphoma Survivors by Left Ventricular Myocardial Work

Anthracycline chemotherapy is associated with the left ventricular (LV) dysfunction, but the conventional echocardiographic parameter is insensitive in detecting subclinical cardiac dysfunction, and the role of echocardiography in children cancer survivors (CCSs) has not been well established. Here, the myocardial work (MW) was employed to evaluate the early effect of the anthracyclines on LV function in children lymphoma survivors, as well as to explore the clinical application value of this modality. 51 children lymphoma survivors treated with anthracyclines were included. During the treatments, the echocardiography was performed at baseline (T0 phase), the 3rd (T1 phase) and 6th (T2 phase) chemotherapeutic cycle, respectively. After that, the conventional echocardiographic parameters, LV global longitudinal strain (GLS), and global myocardial work (GMW) parameters were obtained. Finally, these echocardiographic parameters were compared to distinguish the differences among three groups, and correlation analysis was used to identify relationship between GMW parameters and LV GLS. Compared with the baseline, we found that there are no significant differences for LVEF and other conventional echocardiographic parameters after chemotherapy, but the value of LV lateral E/E' increased at T1 and T2 group. The GLS, global work index, global constructed work, and global work efficiency were decreased, while the global wasted work was increased after chemotherapy (all P < 0.05). The correlation analysis showed that the GLS has significant correlation with GMW parameters (all P < 0.001). The MW, as a new noninvasive echocardiography modality, could be used to quantitatively evaluate the LV MW in children lymphoma survivors treated with anthracyclines, which providing a sensitive method to early detect the children's LV dysfunction after the chemotherapy.

Lethal Immune Myocarditis and Myasthenia Gravis Due to Anti-PD-1 Treatment for a Bladder Cancer Patient: A Case Report and Possible Treatment Inspiration

Immune checkpoint inhibitors (ICI) have become a new hope for many patients with advanced cancer by blocking tumor immune escape. Bladder cancer is a common malignant tumor of the urinary tract epithelium that often relapses and metastasizes after surgery, chemotherapy, and radiotherapy. Immunotherapy has dramatically improved patient survival rates and clinical benefits as a new, potentially effective therapy. However, avoidance of various immune-related adverse events (irAEs) remains an implausible idea. ICI-induced myocarditis is different from viral myocarditis, and mortality is still high with the current treatment. We report the case of an 82-year-old female patient with ICI-induced fulminant myocarditis and myasthenia gravis. Although she actively accepted the current mainstream treatment for immune-related myocarditis and myasthenia, she died of heart and respiratory failure. Analyzing and reporting the patient's disease development process and the changes in related indicators may help peers gain a deeper understanding of immune-related adverse events and reduce the mortality of immune-related myocarditis.

Use of new and emerging cancer drugs: what the cardiologist needs to know

The last decade has witnessed a paradigm shift in cancer therapy, from non-specific cytotoxic chemotherapies to agents targeting specific molecular mechanisms. Nonetheless, cardiovascular toxicity of cancer therapies remains an important concern. This is particularly relevant given the significant improvement in survival of solid and haematological cancers achieved in the last decades. Cardio-oncology is a subspecialty of medicine focusing on the identification and prevention of cancer therapy-related cardiovascular toxicity (CTR-CVT). This review will examine the new definition of CTR-CVT and guiding principles for baseline cardiovascular assessment and risk stratification before cancer therapy, providing take-home messages for non-specialized cardiologists.

Immune checkpoint inhibitor-related myositis and myocarditis: diagnostic pitfalls and imaging contribution in a real-world, institutional case series

BACKGROUND

Immune checkpoint inhibitors (ICIs) are reshaping the prognosis of many cancers, but often cause immune-related adverse events (irAEs). Among neurological irAEs, myositis is the most frequently reported. Our aim is to describe clinical and non-clinical characteristics, treatment and outcome of all irMyositis (skeletal limb-girdle and/or ocular myositis) and irMyocarditis cases in our reference center.

METHODS

We retrospectively enrolled all irMyositis/irMyocarditis patients seen between 2018 and 2022. We reviewed demographics, clinical characteristics, biological, neurophysiological, imaging workup, treatment and outcome.

RESULTS

We included 14 consecutive patients. The most frequent treatments were pembrolizumab (35%) or ipilimumab-nivolumab combination (35%). Limb-girdle, ocular (non-fluctuating palpebral ptosis and/or diplopia with or without ophthalmoparesis) and cardiac phenotypes were equally distributed, overlapping in 40% of cases. Ocular involvement was frequently misdiagnosed; review of brain MRIs disclosed initially missed signs of skeletal myositis in one patient and ocular myositis in 3. Seven patients had other co-existing irAEs. When performed, myography showed a myogenic pattern. CK was elevated in 8/15 patients, troponin-T in 12/12 and troponin-I in 7/9 tested patients. ICI were discontinued in all cases, with further immunosuppressive treatment in nine patients. In most cases, neurological and cardiological outcome was good at last follow-up.

CONCLUSION

Myositis is a potentially severe irAE. Despite its heterogeneous presentation, some highly suggestive clinical symptoms, such as ocular involvement, or radiological signs should raise physicians' attention to avoid misdiagnosis. We thus recommend a multidisciplinary assessment (including complete neuromuscular evaluation) even in case of isolated myocarditis. Our series underlines the importance of an early diagnosis, since suspension of ICI and adequate treatment are usually associated with good functional outcome.

Cardiac magnetic resonance-based layer-specific strain in immune checkpoint inhibitor-associated myocarditis

AIMS

To assess the different imaging characteristics between corticosteroid-sensitive (CS) and corticosteroid-refractory (CR) immune checkpoint inhibitor-associated myocarditis (ICIaM) with cardiac magnetic resonance (CMR) and the potential CMR parameters in the early detection of CR ICIaM.

METHODS AND RESULTS

Thirty-five patients diagnosed with ICIaM and 30 age and gender-matched cancer patients without a history of ICI treatment were enrolled. CMR with contrast was performed within 2 days of clinical suspicion. Left ventricular ejection fraction (LVEF) and late gadolinium enhancement (LGE) were assessed by CMR. LV sub-endocardial (GLSendo) and sub-epicardial (GLSepi) global longitudinal strains were quantified by offline feature tracking analysis. CS and CR ICIaM were defined based on the trend of Troponin I and clinical course during corticosteroid treatment. All 35 patients presented with non-fulminant symptoms upon initial assessment. Twenty patients (57.14%) were sensitive, and 15 (42.86%) were refractory to corticosteroids. Compared with controls, 22 patients (62.86%) with ICIaM developed LGE. LVEF decreased in CR ICIaM compared with the CS group and controls. GLSendo (-14.61 ± 2.67 vs. -18.50 ± 2.53, P < 0.001) and GLSepi (-14.75 ± 2.53 vs. -16.68 ± 2.05, P < 0.001) significantly increased in patients with CR ICIaM compared with the CS ICIaM. In patients with CS ICIaM, although GLSepi (-16.68 ± 2.05 vs. -19.31 ± 1.80, P < 0.001) was impaired compared with the controls, GLSendo was preserved. There was no difference in CMR parameters between LGE-positive and negative groups. LVEF, GLSendo, and GLSepi were predictors of CR ICIaM. When LVEF, GLSendo, and GLSepi were included in multivariate analysis, only GLSendo remained an independent predictor of CR ICIaM (OR: 2.170, 95% CI: 1.189-3.962, P = 0.012). A GLSendo of ≥-17.10% (sensitivity, 86.7%; specificity, 80.0%; AUC, 0.860; P < 0.001) could predict CR ICIaM in the ICIaM cohort. Kaplan-Meier analysis showed that in patients with impaired GLSendo of ≥-17.10%, cardiovascular adverse events (CAEs) occurred much earlier than in patients with preserved GLSendo of <-17.10% (Log-rank test P = 0.017).

CONCLUSIONS

CR and CS ICIaM demonstrated different functional and morphological characteristics in different myocardial layers. An impaired GLSendo could be a helpful parameter in early identifying corticosteroid-refractory individuals in the ICIaM population.

Coxsackie B virus-induced myocarditis in a patient with a history of lymphoma: A case report and review of literature

INTRODUCTION

In rare occasions, coxsackievirus infections can cause serious illness, such as encephalitis and myocarditis. The immunotherapies of cancer could increase the risk of myocarditis, especially when applying immune checkpoint inhibitors. Herein, we report a rare case of Coxsackie B virus-induced myocarditis in a patient with a history of lymphoma.

CASE PRESENTATION

A 32-year-old woman was admitted to the hospital with recurrent fever for more than 20 days, and she had a history of lymphoma. Before admission, the positron emission tomography/computed tomography result indicated that the patient had no tumor progression, and she was not considered the cancer-related fever upon arriving at our hospital. Patient's red blood cell, platelet count, and blood pressure were decreased. In addition, she had sinus bradycardia and 3 branch blocks, which was consistent with acute high lateral and anterior wall myocardial infarction. During hospitalization, the patient had recurrent arrhythmia, repeated sweating, poor mentation, dyspnea, and Coxsackie B virus were detected in patient's blood samples by pathogen-targeted next-generation sequencing. The creatine kinase, creatine kinase MB, and N-terminal pro-brain natriuretic peptide were persistently elevated. Consequently, the patient was diagnosed with viral myocarditis induced by Coxsackie B virus, and treated with acyclovir, gamma globulin combined with methylprednisolone shock therapy, trimetazidine, levosimendan, sildenan, continuous pump pressors with m-hydroxylamine, entecavir, adefovir, glutathione, pantoprazole, and low-molecular-weight heparin. Her symptoms worsened and died.

CONCLUSION

We reported a case with a history of lymphoma presented with fever, myocardial injury, who was ultimately diagnosed with Coxsackie B virus-induced myocarditis. Moreover, pathogen-targeted next-generation sequencing indeed exhibited higher sensitivity compared to mNGS in detecting Coxsackie B virus.

The role of circulating biomarkers in predicting the 30-day mortality of immune checkpoint inhibitors-related myocarditis: a retrospective cohort study

Immune checkpoint inhibitors-related myocarditis (ICIs-M) is a rare and highly lethal immune-related adverse events (irAEs) in common irAEs. This study aims to find circulating biomarkers that can reflect disease state and prognosis accurately. 48 patients with ICIs-M were enrolled according to the diagnostic criteria for ICIs-related myocarditis. For all enrolled patients, valuable information was extracted retrospectively from the medical system, mainly including demographic information, tumor information and laboratory examination. The follow-up period was defined as 30 days after the first diagnosis of ICIs-M. In this study, the 30-day mortality rate of ICIs-M was 24.4%. After adjusting for potential confounding factors using multivariate analysis tools, we demonstrated the excellent performance of biomarkers in predicting 30-day mortality in patients with ICIs-M, including PLT (hazard ratio (HR), 1.07; 95% confidence interval (95%CI), 1.01-1.14; p = 0.028), ALT (HR, 1.23; 95%CI, 1.06-1.41; p = 0.005), AST(HR, 1.06; 95%CI, 1.01-1.10; p = 0.015), LDH (HR, 1.15; 95%CI, 1.04-1.26; p = 0.004), troponin I(HR, 1.44; 95%CI, 1.09-1.89; p = 0.009), PLR (blood plate/lymphocyte) (HR, 1.04; 95% CI, 1.01-1.07; p = 0.024), LAR (lactate dehydrogenase/albumin) (HR, 1.05; 95%CI, 1.01-1.09; p = 0.012), and AAR (aspartate transaminase/albumin) (HR, 1.18; 95%CI, 1.00-1.39; p = 0.048). The analysis of the receiver operating characteristic showed that biomarkers with area under curve (AUC) greater than or equal to 0.80 were LDH (cutoff value, 724.5; AUC, 0.86; 95%CI, 0.75-0.97), LAR (cutoff value, 18.11; AUC, 0.87; 95%CI, 0.76-0.97), troponin I (cutoff value, 0.87; AUC, 0.80; 95%CI, 0.62-0.99), and AAR(cutoff value, 1.52; AUC, 0.80; 95%CI, 0.61-0.98). LDH, LAR, troponin I, and AAR are a group of promising biomarkers that demonstrate excellent predictive ability in predicting the 30-day mortality rate of immune-related myocarditis.

Immune checkpoint inhibitors break whose heart? Perspectives from cardio-immuno-oncology

Immune checkpoint inhibitors (ICIs) are monoclonal antibody antagonists, which can block cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed death-1/ligand-1 (PD-1/PD-L1) pathways, and other molecules exploited by tumor cells to evade T cell-mediated immune response. ICIs have transformed the treatment landscape for various cancers due to their amazing efficacy. Many anti-tumor therapies, including targeted therapy, radiotherapy, and chemotherapy, combine ICIs to make the treatment more effective. However, the off-target immune activation caused by ICIs may lead to a broad spectrum of immune-related adverse events (irAEs) affecting multiple organ systems. Among irAEs, cardiotoxicity induced by ICIs, uncommon but fatal, has greatly offset survival benefits from ICIs, which is heartbreaking for both patients and clinicians. Consequently, such cardiotoxicity requires special vigilance, and it has become a common challenge both for patients and clinicians. This article reviewed the clinical manifestations and influence of cardiotoxicity from the view of patients and clinicians, elaborated on the underlying mechanisms in conjunction with animal studies, and then attempted to propose management strategies from a cardio-immuno-oncology multidisciplinary perspective.

Pembrolizumab-induced myocarditis with complete atrioventricular block and concomitant myositis in a metastatic bladder cancer patient: a case report and review of the literature

BACKGROUND

The cardiovascular system is among the least systems affected by immune-related adverse events. We report a rare life-threatening case of pembrolizumab-induced myocarditis with complete atrioventricular block and concomitant myositis in a metastatic bladder cancer patient.

CASE PRESENTATION

An 82-year-old Caucasian female with invasive urothelial carcinoma, started on first-line pembrolizumab, was admitted four days after receiving her second dose for severe asthenia, diffuse muscle aches, neck pain, and lethargy. In the emergency department, she had several episodes of bradycardia reaching 40 beats per minute associated with general discomfort and fatigue. Electrocardiography showed a third-degree atrioventricular heart block, while the patient remained normotensive. Cardiac damage parameters were altered with elevated levels of creatine phosphokinase of 8930 U/L, suggestive of immune checkpoint inhibitor-induced myositis, and troponin T of 1.060 ng/mL. Transthoracic echocardiography showed a preserved ejection fraction. Pembrolizumab-induced myocarditis was suspected. Therefore, treatment was initiated with high-dose glucocorticoids for 5 days, followed by a long oral steroid taper. A pacemaker was also implanted. Treatment resulted in the resolution of heart block and a decrease in creatine phosphokinase to the normal range.

CONCLUSION

Life-threatening cardiac adverse events in the form of myocarditis may occur with pembrolizumab use, warranting vigilant cardiac monitoring. Troponin monitoring in high-risk patients, along with baseline echocardiography may help identify this complication promptly to prevent life-threatening consequences.

Circulating biomarkers in the diagnosis and prognosis of immune checkpoint inhibitor-related myocarditis: time for a risk-based approach

Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that block immune checkpoints and therefore activate immune cells, allowing them to recognize and attack cancer cells. ICIs have revolutionized oncology practice, but their use has been complicated by immune-related adverse events (irAEs). Of cardiovascular (CV) irAEs, ICI-related myocarditis has received significant attention due to high mortality rates, ranging from 25% to 50%, despite its overall low incidence. Establishing the early diagnosis of ICI-myocarditis is important for early initiation of steroids and consideration of hospitalization in patients who are at risk for hemodynamic compromise and need high acuity care in a tertiary setting. In this review, we summarize the diagnostic and prognostic tools for ICI-myocarditis, including electrocardiography, echocardiography, cardiac magnetic resonance imaging, with emphasis on circulating biomarkers. Cardiac troponins (cTns) are an essential component of the diagnosis of ICI-myocarditis, and we provide a summary of the recent studies that utilized different assays (cTnI vs. cTnT) and outcomes (diagnosis vs. prognosis including major adverse cardiac outcomes). With the exponential increase in ICI use across different oncology indications, there is a major need to include biomarkers in risk stratification to guide diagnosis and treatment. Our review proposes a framework for future multisite registries, including cTn evaluation at baseline and at the time of irAE suspicion, with development of central biobanking to allow head-to-head evaluation and clinical validation of different biomarker assays in ICI-myocarditis. This approach, with the inclusion of CV biomarkers into clinical and pragmatic oncology trials, holds promise to improve the early recognition and management of ICI-myocarditis and CV irAEs, thus leading to better outcomes.

Achilles' Heel of currently approved immune checkpoint inhibitors: immune related adverse events

Immunotherapy has revolutionized the cancer treatment landscape by opening up novel avenues for intervention. As the use of immune checkpoint inhibitors (ICIs) has exponentially increased, so have immune-related adverse events (irAEs). The mechanism of irAEs may involve the direct damage caused by monoclonal antibodies and a sequence of immune responses triggered by T cell activation. Common side effects include dermatologic toxicity, endocrine toxicity, gastrointestinal toxicity, and hepatic toxicity. While relatively rare, neurotoxicity, cardiotoxicity, and pulmonary toxicity can be fatal. These toxicities pose a clinical dilemma regarding treatment discontinuation since they can result in severe complications and necessitate frequent hospitalization. Vigilant monitoring of irAEs is vital in clinical practice, and the principal therapeutic strategy entails the administration of oral or intravenous glucocorticoids (GSCs). It may be necessary to temporarily or permanently discontinue the use of ICIs in severe cases. Given that irAEs can impact multiple organs and require diverse treatment approaches, the involvement of a multidisciplinary team of experts is imperative. This review aims to comprehensively examine the pathogenesis, clinical manifestations, incidence, and treatment options for various irAEs.

Immune checkpoint inhibitors - the revolutionary cancer immunotherapy comes with a cardiotoxic price

The development of immune checkpoint inhibitors (ICIs) has provided a novel and revolutionary treatment option for previously incurable cancers. However, this major advancement is accompanied by a spectrum of cardiotoxic adverse events that are uncommon but potentially fatal. The oncologic indications of ICIs are becoming increasingly complex, requiring robust clinical monitoring to assess for cardiovascular complications. This is reflected in the recent introduction of the first cardio-oncology guidelines, a sign of the cardiovascular community's recognition that seeks to match this dynamic. The aim of this review is to summarize the cardiac side effects of ICI, with an emphasis on prevalence, diagnosis, and treatment options.

Corticosteroid-resistant immune-related adverse events: a systematic review

Immune checkpoint inhibitor (ICI) treatment has become an important therapeutic option for various cancer types. Although the treatment is effective, ICI can overstimulate the patient's immune system, leading to potentially severe immune-related adverse events (irAEs), including hepatitis, colitis, pneumonitis and myocarditis. The initial mainstay of treatments includes the administration of corticosteroids. There is little evidence how to treat steroid-resistant (sr) irAEs. It is mainly based on small case series or single case reports. This systematic review summarizes available evidence about sr-irAEs. We conducted a systematic literature search in PubMed. Additionally, we included European Society for Medical Oncology, Society for Immunotherapy of Cancer, National Comprehensive Cancer Network and American Society of Clinical Oncology Guidelines for irAEs in our assessment. The study population of all selected publications had to include patients with cancer who developed hepatitis, colitis, pneumonitis or myocarditis during or after an immunotherapy treatment and for whom corticosteroid therapy was not sufficient. Our literature search was not restricted to any specific cancer diagnosis. Case reports were also included. There is limited data regarding life-threatening sr-irAEs of colon/liver/lung/heart and the majority of publications are single case reports. Most publications investigated sr colitis (n=26), followed by hepatitis (n=21), pneumonitis (n=17) and myocarditis (n=15). There is most data for mycophenolate mofetil (MMF) to treat sr hepatitis and for infliximab, followed by vedolizumab, to treat sr colitis. Regarding sr pneumonitis there is most data for MMF and intravenous immunoglobulins (IVIG) while data regarding infliximab are conflicting. In sr myocarditis, most evidence is available for the use of abatacept or anti-thymocyte globulin (ATG) (both with or without MMF) or ruxolitinib with abatacept. This review highlights the need for prompt recognition and treatment of sr hepatitis, colitis, pneumonitis and myocarditis. Guideline recommendations for sr situations are not defined precisely. Based on our search, we recommend-as first line treatment-(1) MMF for sr hepatitis, (2) infliximab for sr colitis, followed by vedolizumab, (3) MMF and IVIG for sr pneumonitis and (4) abatacept or ATG (both with or without MMF) or ruxolitinib with abatacept for sr myocarditis. These additional immunosuppressive agents should be initiated promptly if there is no sufficient response to corticosteroids within 3 days.

Immune Checkpoint Inhibitor-Associated Myocarditis: A Literature Review

Recently in the field of oncology, immune checkpoint inhibitors (ICI) are being increasingly utilized both in clinical trials and in clinical practice. It is a form of biological therapy that targets tumors by activating the immune system, which in turn eliminates proliferating cancer cells. These have numerous immune-related adverse events (irAEs), one of which is myocarditis, which has high rates of mortality. This article was a narrative review of myocarditis related to ICI use.  Studies from the PubMed, Cochrane, and American Society of Clinical Oncology (ASCO) databases were used in writing this review. The databases were searched for original publications for adverse effects related to ICI use and myocarditis specifically. There are numerous published instances of cancer immunotherapy causing myocarditis. ICI therapy has numerous benefits, as it upregulates the immune system to target cancer cells, utilizing the body's own defense mechanisms to target proliferating cells. Myocarditis is a serious side effect, however. Therefore, on balance, these monotherapies are worth using. While this literature review primarily identifies cross-reaction as the main mechanism of myocarditis, there are other possible mechanisms. One proposed mechanism involves a shared antigen between the myocardial tissue and the tumor. This mechanism is called molecular mimicry, where the monoclonal antibody attacks both the myocardial tissue and the tumor cell. Management of ICI-induced myocarditis has not been studied by randomized controlled trials or prospective studies, but based on previous case reports and case series it is mostly treated with steroids initially. An ICI rechallenge after temporary discontinuation appears conceivable in many cases, especially given its therapeutic effects, but only limited data are available on the safety of a rechallenge after an irAE. The lack of RCTs regarding rechallenge with an ICI after irAE, more so specifically about myocarditis, along with the overall results and the complexity involved in such cases once again emphasize the need to make decisions on an individual basis by a multidisciplinary expert working group. At the same time, the focus should also be on publishing more data as the need will grow along with the indications for ICI therapies.

The toxic tango: TKI and TCI cardiotoxicities

BACKGROUND

Immune checkpoint inhibitors (ICI) and Tyrosine kinase inhibitors (TKI) are effective for several types of cancers, but they can have several cardiotoxicity sides effects. We present a case of TKI-ICI toxicity resulting in multiorgan inflammatory syndrome with myocarditis and thrombotic STEMI that were successfully treated with high-dose steroids and PCI.

CASE PRESENTATION

Seventy-two year-old man patient treated with on pembrolizumab 200 mg IV every 3 weeks and Axitinib 5 mg PO q12h for the past 5 months complained of acute shortness of breath, altered mental status, and chronic diarrhea. Coronary angiography demonstrated a thrombotic lesion in the right coronary artery (RCA) that was treated successfully with percutaneous coronary intervention (PCI). Despite PCI he continued to complain of shortness of breath further workup with Cardiac MRI (CMR) was obtained showed an ejection fraction of 38%, small pericardial effusion, and delayed gadolinium enhancement (DGE) in the inferior wall suggestive of myocarditis. An empirical trial of high-dose steroids improved all patient symptoms and ejection fraction; therefore, the chemotherapy regimen was changed.

CONCLUSION

This case report highlights the potential vasculogenic effects of Axitinib and immune-related myocarditis of pembrolizumab. Cardiologists and oncologists should be vigilant for the cardiotoxic effects of Axitinib and pembrolizumab.

Immune Responses in Checkpoint Myocarditis Across Heart, Blood, and Tumor

Immune checkpoint inhibitors (ICIs) are widely used anti-cancer therapies that can cause morbid and potentially fatal immune-related adverse events (irAEs). ICI-related myocarditis (irMyocarditis) is uncommon but has the highest mortality of any irAE. The pathogenesis of irMyocarditis and its relationship to anti-tumor immunity remain poorly understood. We sought to define immune responses in heart, tumor, and blood during irMyocarditis and identify biomarkers of clinical severity by leveraging single-cell (sc)RNA-seq coupled with T cell receptor (TCR) sequencing, microscopy, and proteomics analysis of 28 irMyocarditis patients and 23 controls. Our analysis of 284,360 cells from heart and blood specimens identified cytotoxic T cells, inflammatory macrophages, conventional dendritic cells (cDCs), and fibroblasts enriched in irMyocarditis heart tissue. Additionally, potentially targetable, pro-inflammatory transcriptional programs were upregulated across multiple cell types. TCR clones enriched in heart and paired tumor tissue were largely non-overlapping, suggesting distinct T cell responses within these tissues. We also identify the presence of cardiac-expanded TCRs in a circulating, cycling CD8 T cell population as a novel peripheral biomarker of fatality. Collectively, these findings highlight critical biology driving irMyocarditis and putative biomarkers for therapeutic intervention.

Immune Checkpoint Inhibitors and Their Cardiovascular Adverse Effects

Immune checkpoint inhibitors (ICIs) have reshaped and have become a well-established treatment modality for multiple advanced-stage malignancies. ICIs block the immune system regulatory checkpoints, namely CTLA-4 and PD-1/PDL1, which provokes excess immune response against self-antigens. Immune modulation with ICIs can result in diverse immune-related adverse events targeting organ systems. Several cases of ICI-related cardiotoxicity were reported, while the actual incidence was likely underestimated due to heterogeneous clinical presentation. These include, but are not limited to, myocarditis, pericarditis, atherosclerosis, and arrhythmia. EKG, Troponin, Echocardiogram (TTE), and Cardiac MRI (CMRI) are indispensable diagnostic tools to aid in the management of cardiac adverse effects. Herein, we review the ICI-mediated cardiovascular adverse events, diagnosis, treatment strategies, and reintroduction of ICIs post-cardiotoxicity.

A comprehensive review on immune checkpoint inhibitors induced cardiotoxicity characteristics and associated factors

Newly approved cancer drugs called ICIs have shown remarkable success in improving patient survival rates, but they also have the potential for inflammatory and immune-related side effects, including those affecting the cardiovascular system. Research has been conducted to understand the development of these toxicities and identify risk factors. This review focuses on the characteristics of ICI-induced cardiotoxicity and discusses the reported risk factors. It is important for cardio-oncologists to understand the basic concepts of these drugs to better understand how cardiotoxicities occur. It might be hard to find reports, where all patients treated with ICIs had developed cardiac toxicity, because there could be other existing and variable factors that influence the likelihood or risk of developing cardiotoxicity during treatment. Various clinical parameters have been explored as potential risk factors, and further investigation is needed through large-scale studies.

Circulating Cardiovascular Biomarkers in Cancer Therapeutics-Related Cardiotoxicity: Review of Critical Challenges, Solutions, and Future Directions

Cardiotoxicity is a growing concern in the oncology population. Transthoracic echocardiography and multigated acquisition scans have been used for surveillance but are relatively insensitive and resource intensive. Innovative imaging techniques are constrained by cost and availability. More sensitive, cost-effective cardiotoxicity surveillance strategies are needed. Circulating cardiovascular biomarkers could provide a sensitive, low-cost solution. Biomarkers such as troponins, natriuretic peptides (NPs), novel upstream signals of oxidative stress, inflammation, and fibrosis as well as panomic technologies have shown substantial promise, and guidelines recommend baseline measurement of troponins and NPs in all patients receiving potential cardiotoxins. Nonetheless, supporting evidence has been hampered by several limitations. Previous reviews have provided valuable perspectives on biomarkers in cancer populations, but important analytic aspects remain to be examined in depth. This review provides comprehensive assessment of critical challenges and solutions in this field, with focus on analytical issues relating to biomarker measurement and interpretation. Examination of evidence pertaining to common and serious forms of cardiotoxicity reveals that improved study designs incorporating larger, more diverse populations, registry-based approaches, and refinement of current definitions are key. Further efforts to harmonize biomarker methodologies including centralized biobanking and analyses, novel decision limits, and head-to-head comparisons are needed. Multimarker algorithms incorporating machine learning may allow rapid, personalized risk assessment. These improvements will not only augment the predictive value of circulating biomarkers in cardiotoxicity but may elucidate both direct and indirect relationships between cardiovascular disease and cancer, allowing biomarkers a greater role in the development and success of novel anticancer therapies.

PCSK9 inhibition ameliorates experimental autoimmune myocarditis by reducing Th17 cell differentiation through LDLR/STAT-3/ROR-γt pathway

Proprotein convertase subtilisin kexin type 9 (PCSK9) was characterized as a protein regulating circulating cholesterol metabolism; however, recent studies demonstrated a role for PCSK9 in inflammatory and autoimmune diseases unrelated to cholesterol alterations. The implication of PCSK9 in myocarditis is unclear and we aim at investigating the roles and mechanisms of PCSK9 in myocarditis. Male BALB/c mice received subcutaneous immunization with MyHC-α peptide on days 0 and 7 to establish the experimental autoimmune myocarditis (EAM) model. PCSK9 inhibitor, evolocumab, was administered subcutaneously once a week starting on day 0 and all mice were euthanized on day 21. Our results showed that PCSK9 inhibition ameliorated the cardiac inflammation of EAM mice. PCSK9 inhibition reduced both the levels of cardiac and peripheral blood PCSK9. We found that CD4+ T cells, CD8+ T cells, macrophages, and cardiomyocytes in the heart of EAM mice could express PCSK9. PCSK9 inhibition decreased the differentiation of cardiac Th17 cells by lowering ROR-γt levels but had no effects on Th1, Th2, and Treg cell differentiation. In vitro experiments of CD4+ T cells, we found that PCSK9 directly promoted Th17 cell differentiation through LDLR/STAT3/ROR-γt pathway. Collectively, we demonstrated that PCSK9 inhibition ameliorated the severity of EAM mice by reducing Th17 cell differentiation. PCSK9 is a promising target for treating myocarditis.

Cardiovascular toxicity of checkpoint inhibitors: review of associated toxicity and design of the Spanish Immunotherapy Registry of Cardiovascular Toxicity

Immune checkpoint inhibitors (ICI) have changed the prognosis of many tumors. However, concerning associated cardiotoxicity has been reported. Little is known about the real-life incidence-specific surveillance protocols or the translational correlation between the underlying mechanisms and the clinical presentation of ICI-induced cardiotoxicity. The lack of data from prospective studies led us to review the current knowledge and to present the creation of the Spanish Immunotherapy Registry of Cardiovascular Toxicity (SIR-CVT), a prospective registry of patients receiving ICI that aims to examine the role of hsa-miR-Chr8:96, (a specific serum biomarker of myocarditis) in the early diagnosis of ICI-induced myocarditis. An exhaustive prospective cardiac imaging study will be performed before and during the first 12 months of treatment. The correlation between clinical, imaging, and immunologic parameters may improve our understanding of ICI-induced cardiotoxicity and enable simpler surveillance protocols. We assess ICI-induced cardiovascular toxicity and describe the rationale of the SIR-CVT.

Recent Advances in Serum Biomarkers for Cardiological Risk Stratification and Insight into the Cardiac Management of the Patients With Hematological Malignancies Treated With Targeted Therapy

Cardiovascular diseases (CVD) have emerged as a common and serious complication of cancer treatment, particularly in patients undergoing cardiotoxic therapies. Over the last few years, the medical community has become increasingly aware of the potential for cardiotoxicity resulting from cancer treatments involving chemotherapy, targeted therapies, and radiation therapy. This recognition is due to the significant risk of morbidity and mortality in cancer patients and survivors resulting from such treatment-induced cardiovascular damage. While the cardiotoxic effects of chemotherapy and targeted therapy have been discussed in medical literature, only a limited number of studies have explored the role of serum biomarkers in cardiological risk stratification. In recent years, serum biomarkers have emerged as a valuable tool for assessing and managing cardiotoxicity in patients with hematological malignancies. This review article provides a summary of the current state of knowledge on the usefulness of biomarkers in managing cardiotoxicity resulting from different targeted therapies throughout the cancer care continuum. Although cardiac biomarkers have demonstrated potential in identifying subclinical cardiotoxicity and tracking the response to cardioprotective treatments, further research is necessary to determine optimal biomarkers and surveillance strategies. The incorporation of cardiac biomarkers into clinical practice in patients undergoing targeted therapies could potentially lead to improved long-term cardiovascular outcomes in cancer patients and survivors.

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.

Sintilimab-Induced Myocarditis in a Patient with Gastric Cancer: A Case Report and Literature Review

Immune checkpoint inhibitors (ICIs) have emerged as a powerful and efficacious therapeutic approach for many cancer patients. Sintilimab is a fully human IgG4 monoclonal antibody that binds with programmed cell death receptor-1 (PD-1) to block its interaction with ligands, thereby enhancing the antitumor effects of T cells. However, ICIs may induce immune-related adverse events (irAEs) in various systems and organs, with fulminant myocarditis being the most severe one. We report the case of a 45-year-old female with gastric cancer who developed chest pain two weeks after chemotherapy with sintilimab; she was diagnosed with immune-associated fulminant myocarditis and experienced an Adams-Stokes syndrome attack in the hospital. Eventually, she was discharged after being treated with methylprednisolone, immunoglobulin, and an IABP.

Immune checkpoint inhibitor-associated myocarditis: a systematic analysis of case reports

Background

Immune checkpoint inhibitors (ICIs) therapy can be complicated by their potential cardiovascular toxicities, including myocarditis. Nowadays, no prospective trials have focused on ICI-associated myocarditis optimized management. Available evidence only come from case reports or series. A systematic case reports analysis was conducted to collect and evaluate emerging evidence of ICI-associated myocarditis to provide more information to clinicians.

Methods

We performed a literature search for eligible case reports or series published between January 2018 and May 2023 using the PubMed database. Then, we extracted interesting information via table form. Finally, this study included 113 publications on 106 patients with ICI-associated myocarditis.

Results

Myocarditis was found to be a highly life-threatening disease, with 53.8% of cases. Over half of cases were life-threatening (G4, 23.6%) or severe (G3, 35.8%) and required glucocorticoids. Higher rates of improvement were associated with the best response to ICI for complete response/partial response (72.7% vs. 53.9%), glucocorticoid administration (30% vs. 22%), and discontinuation of ICI (58.8% vs. 32.1%). Consequently, ICI-associated G3-G4 myocarditis should be treated with a combination of discontinuation of ICIs, high-dose glucocorticoids, other drugs, chemical drugs, plasma exchange, and life support. For moderate G1 or G2 cases, discontinuation of ICIs and regular-dose glucocorticoids should be considered.

Conclusion

Once full recovery or improvement was achieved; glucocorticoids can be administered at low doses or stopped. Notably, re-challenge with ICIs appears feasible after resolution or meaningful improvement of myocarditis.

Rationale and design of the ARAMIS trial: Anakinra versus placebo, a double blind randomized controlled trial for the treatment of acute myocarditis

BACKGROUND

Acute myocarditis is an inflammation of the myocardium that can cause life-threatening events. However, anti-inflammatory strategies did not reduce the risk of clinical outcomes in randomized trials. Recently, experimental studies have suggested that specific blockade of the interleukin-1β immune innate pathway could be effective in acute myocarditis.

AIM

To test the hypothesis that inhibition of the interleukin-1β immune innate pathway can reduce the risk of clinical events in acute myocarditis.

METHODS

The "Anakinra versus placebo double blind Randomized controlled trial for the treatment of Acute MyocarditIS" (ARAMIS) trial (ClinicalTrials.gov identifier: NCT03018834) is a national multicentre randomized parallel-group double blind study among symptomatic patients with elevated cardiac troponin and cardiac magnetic resonance-proven acute myocarditis. Patients (n=120) are randomized within 72hours of hospital admission to receive a daily subcutaneous dose of anakinra 100mg or placebo during the hospitalization, in addition to standard of care, including an angiotensin-converting enzyme inhibitor and a beta-blocker. The primary endpoint is the number of days alive free from any myocarditis complication, including ventricular arrhythmias, heart failure, recurrent chest pain requiring medication and ventricular dysfunction (defined as left ventricular ejection fraction<50%), from randomization to 28 days after hospital discharge. At 28 days after discharge, patients with normal left ventricular ejection fraction are then randomized to angiotensin-converting enzyme inhibitor continuation or discontinuation and all patients are followed for 1 year, with regular left ventricular function evaluation.

CONCLUSIONS

ARAMIS is the first trial evaluating inhibition of the interleukin-1β immune innate pathway in the setting of acute myocarditis. Although of small size, it will be the largest randomized trial in acute myocarditis, a serious and poorly studied cardiac condition.

PD-1 inhibitors-associated myocarditis in non-small cell lung cancer patients

Background

Immune checkpoint inhibitors (ICIs)-associated myocarditis remains a rare but fatal adverse event. The authors sought to provide a comprehensive clinical description of ICI-associated myocarditis by analyzing symptoms, laboratory indicators, imaging features, and management of ICI-associated myocarditis in patients with non-small cell lung cancer (NSCLC).

Methods

A retrospective study was conducted to analyze 14 ICI-associated myocarditis cases and 45 control patients to clarify clinical features of ICI-associated myocarditis. Detailed laboratory tests and imaging examinations were performed in 14 cases, and the rescue process and follow-up after the onset of myocarditis were recorded.

Results

A total of 14 (2.08%) NSCLC patients developed ICI-related myocarditis, with a median time of onset of 34 days (interquartile range, 12 to 146 days) after ICI initiation. The most common concurrent adverse events in cases were myositis (P<0.001) and peripheral neuritis (P<0.001). Among cases, cardiac troponin I (cTnI) levels were abnormally elevated in 92% of patients, and electrocardiogram (ECG) showed abnormal in all cases. Steroid therapy was used in 92.9% of patients with ICI-associated myocarditis, of which the response rate to steroids was 76.9% and the mortality rate was 7.1%. A dose of 1 g/d of glucocorticoid supplemented by immunoglobulin was observed to be effective for severe myocarditis.

Conclusions

Early identification and treatment are essential for managing myocarditis caused by ICI. Routine monitoring of cTnI level and ECG is most sensitive for the early diagnosis of ICI-related myocarditis. High-dose of glucocorticoids can effectively relieve the symptoms of ICI-associated myocarditis and stabilize the condition, especially for fulminant myocarditis.

Complete heart block is a significant predictor of mortality in immune checkpoint inhibitor myocarditis

BACKGROUND

Immune checkpoint inhibitor (ICI) myocarditis is associated with significant mortality risk. Electrocardiogram (ECG) changes in ICI myocarditis have strong prognostic value. However the impact of complete heart block (CHB) is not well defined. This study sought to evaluate the impact of CHB on mortality in ICI myocarditis, and to identify clinical predictors of mortality and CHB incidence.

METHODS

We conducted a retrospective cohort study of patients with ICI myocarditis at three Mayo Clinic sites from 1st January 2010 to 31st September 2022 to evaluate mortality rates at 180 days. Clinical, laboratory, ECG, echocardiographic, and cardiac magnetic resonance imaging (CMR) characteristics were assessed. Cox and logistic regression were performed for associations with mortality and CHB respectively.

RESULTS

Of 34 identified cases of ICI myocarditis, 7 (20.6%) had CHB. CHB was associated with higher mortality (HR 7.41, p = 0.03, attributable fraction 86.5%). Among those with CHB, troponin T (TnT) < 1000 ng/dL, low white blood cell count and high ventricular rate at admission were protective. There was trend towards increased survival among patients who underwent permanent pacemaker insertion (p = 0.051), although most experienced device lead complications. Factors associated with development of CHB included prolonged PR and QRS intervals and low Sokolow Lyon Index. Where these were normal and TnT was < 1000 ng/dL, no deaths occurred. Impaired myocardial longitudinal strain was sensitive for ICI myocarditis but was not prognostically significant.

CONCLUSION

There is a strong temporal association between CHB and early mortality in people with ICI myocarditis. Focusing on arrhythmogenic complications can be helpful in predicting outcomes for this group of critically ill individuals.

Management of respiratory failure in immune checkpoint inhibitors-induced overlap syndrome: a case series and review of the literature

BACKGROUND

Checkpoint inhibitor-induced overlap syndrome ([OS] myocarditis, and myositis with or without myasthenia gravis) is rare but life-threatening.

CASES PRESENTATION

Here we present a case series of four cancer patients that developed OS. High troponinemia raised the concern for myocarditis in all the cases. However, the predominant clinical feature differed among the cases. Two patients showed marked myocarditis with a shorter hospital stay. The other two patients had a prolonged ICU stay due to severe neuromuscular involvement secondary to myositis and myasthenia gravis. Treatment was based on steroids, plasmapheresis, intravenous immunoglobulin, and immunosuppressive biological agents.

CONCLUSION

The management of respiratory failure is challenging, particularly in those patients with predominant MG. Along with intensive clinical monitoring, bedside respiratory mechanics can guide the decision-making process of selecting a respiratory support method, the timing of elective intubation and extubation.

Role of Biomarkers in the Management of Immune-Checkpoint Inhibitor-Related Myocarditis

PURPOSE OF REVIEW

Immune checkpoint inhibitor (ICI)-related myocarditis poses a major clinical challenge given its non-specific presentation, rapid progression, and high mortality rate. Here, we review the role of blood-based biomarkers in the clinical management of patients with ICI-related myocarditis.

RECENT FINDINGS

Myocardial injury, its unique pattern, and the co-occurrence with myositis are defining features of ICI-related myocarditis. Non-cardiac biomarkers, specifically creatinine phosphokinase, precedes the symptomatic presentation and is highly sensitive for diagnosing ICI-related myocarditis, making them useful screening biomarkers. Combined elevations in cardiac troponins and non-cardiac biomarkers improve the confidence of an ICI myocarditis diagnosis. High troponin and creatinine phosphokinase levels are strongly associated with severe outcomes. We propose biomarker-based algorithms for the monitoring and diagnosis of ICI-related myocarditis. Biomarkers, such as cardiac troponins and creatine phosphokinase, can be used in combination in the monitoring, diagnosis, and prognostication of patients with ICI-related myocarditis.

Cardiovascular Molecular Imaging With Fluorine-19 MRI: The Road to the Clinic

Fluorine-19 (19F) magnetic resonance imaging is a unique quantitative molecular imaging modality that makes use of an injectable fluorine-containing tracer that generates the only visible 19F signal in the body. This hot spot imaging technique has recently been used to characterize a wide array of cardiovascular diseases and seen a broad range of technical improvements. Concurrently, its potential to be translated to the clinical setting is being explored. This review provides an overview of this emerging field and demonstrates its diagnostic potential, which shows promise for clinical translation. We will describe 19F magnetic resonance imaging hardware, pulse sequences, and tracers, followed by an overview of cardiovascular applications. Finally, the challenges on the road to clinical translation are discussed.

Cardiovascular Toxicity of Immune Checkpoint Inhibitors: A Guide for Clinicians

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment and care of patients with cancer owing to unique features, including the occurrence of the so-called immune-related adverse events (irAEs). A multidisciplinary team, possibly including a cardio-oncology specialist, is warranted to achieve a favorable patient outcome. Cardiovascular toxicity, especially myocarditis, emerged as a life-threatening irAE in the real-word setting, and the European Society of Cardiology has recently published the first guideline on cardio-oncology to increase awareness and promote a standardized approach to tackle this complex multimodal issue, including diagnostic challenges, assessment, treatment, and surveillance of patients with cancer receiving ICIs. In this article, through a question & answer format made up of case vignettes, we offer a clinically oriented overview on the latest advancements of ICI-related cardiovascular toxicity, focusing on myocarditis and associated irAEs (myositis and myasthenia gravis within the so-called overlap syndrome), with the purpose of assisting clinicians and healthcare professionals in daily clinical practice.

Cardiovascular Toxicity Associated With Immune Checkpoint Inhibitor Therapy: A Comprehensive Review

Immune checkpoint inhibitors (ICIs), a significant breakthrough treatment of cancer, exert their function through enhancing the immune system's ability to recognize and attack cancer cells. However, these revolutionary cancer treatments have been associated with a range of immune-related adverse effects, including cardiovascular toxicity. The most commonly reported cardiovascular toxicities associated with ICIs are myocarditis, pericarditis, arrhythmias, and vasculitis. These cardiovascular manifestations are often severe and can lead to life-threatening complications. Therefore, prompt identification and management of these toxicities is critical, and a multidisciplinary teamwork by cardiologists and oncologists are required to ensure optimal patient outcomes. In this review, we summarize the current knowledge on the mechanisms underlying ICI-associated cardiovascular toxicity, clinical presentations of these toxicities, potential risk factors, diagnosis, management, and surveillance strategies during ICI therapy. While ICIs have already transformed cancer treatment, further research is needed to better understand and manage their immune-related cardiovascular effects, and possibly, to identify biomarkers which can predict the occurrence of these cardiovascular complications.

Immunopathogenesis and immunomodulatory therapy for myocarditis

Myocarditis is an inflammatory cardiac disease characterized by the destruction of myocardial cells, infiltration of interstitial inflammatory cells, and fibrosis, and is becoming a major public health concern. The aetiology of myocarditis continues to broaden as new pathogens and drugs emerge. The relationship between immune checkpoint inhibitors, severe acute respiratory syndrome coronavirus 2, vaccines against coronavirus disease-2019, and myocarditis has attracted increased attention. Immunopathological processes play an important role in the different phases of myocarditis, affecting disease occurrence, development, and prognosis. Excessive immune activation can induce severe myocardial injury and lead to fulminant myocarditis, whereas chronic inflammation can lead to cardiac remodelling and inflammatory dilated cardiomyopathy. The use of immunosuppressive treatments, particularly cytotoxic agents, for myocarditis, remains controversial. While reasonable and effective immunomodulatory therapy is the general trend. This review focuses on the current understanding of the aetiology and immunopathogenesis of myocarditis and offers new perspectives on immunomodulatory therapies.

Mediators and mechanisms of immune checkpoint inhibitor-associated myocarditis: Insights from mouse and human

The broad application of immune checkpoint inhibitors (ICIs) has led to significant gains in cancer outcomes. By abrogating inhibitory signals, ICIs promote T cell targeting of cancer cells but can frequently trigger autoimmune manifestations, termed immune-related adverse events (irAEs), affecting essentially any organ system. Among cardiovascular irAEs, immune-related myocarditis (irMyocarditis) is the most described and carries the highest morbidity. The currently recommended treatment for irMyocarditis is potent immunosuppression with corticosteroids and other agents, but this has limited evidence basis. The cellular pathophysiology of irMyocarditis remains poorly understood, though mouse models and human data have both implicated effector CD8+ T cells, some of which are specific for the cardiomyocyte protein α-myosin. While the driving molecular signals and transcriptional programs are not well defined, the involvement of chemokine receptors such as CCR5 and CXCR3 has been proposed. Fundamental questions regarding why only approximately 1% of ICI recipients develop irMyocarditis and why irMyocarditis carries a much worse prognosis than other forms of lymphocytic myocarditis remain unanswered. Further work in both murine systems and with human samples are needed to identify better tools for diagnosis, risk-stratification, and treatment.

Diagnostic yield, safety and therapeutic consequences of myocardial biopsy in clinically suspected fulminant myocarditis unweanable from mechanical circulatory support

BACKGROUND

Fulminant myocarditis is a rare and severe disease whose definite and etiological diagnoses rely on pathological examination. Albeit, myocardial biopsy can be associated with significant morbidity and mortality, its therapeutic consequences are unclear. We conducted a study to determine the diagnostic yield, the safety and the therapeutic consequences of myocardial biopsy in patients with fulminant clinically suspected myocarditis unweanable from mechanical circulatory support (MCS).

METHODS

Monocenter, retrospective, observational cohort study in a 26-bed French tertiary ICU between January 2002 and February 2019. Inclusion of all fulminant clinically suspected myocarditis patients undergoing in-ICU myocardial biopsy while being on MCS. The primary endpoint was the proportion of patients classified as definite myocarditis using Bonaca criteria before and after including myocardial biopsy results.

RESULTS

Forty-seven patients (median age 41 [30-47], female 53%) were included: 55% died before hospital discharge, 34% could be bridged-to-recovery and 15% bridged-to-transplant. Myocardial biopsy was endomyocardial or surgical in 36% and 64% cases respectively. Tamponade requiring emergency pericardiocentesis occurred in 29% patients after endomyocardial biopsy. After adding the biopsy results in the Bonaca classification algorithm the percentage of definite myocarditis raised from 13 to 55% (p < 0.0001). The rate of biopsy-related treatments modifications was 13%, leading to patients' recovery in only 4% patients.

CONCLUSIONS

In clinically suspected myocarditis unweanable from MCS, myocardial biopsy increased the rate of definite myocarditis but was associated with a low rate of treatment modification and a significant proportion of adverse events. We believe the benefit/risk ratio of myocardial biopsy should be more carefully weighted in these frail and selected patients than suggested by actual guidelines. Further prospective studies are now needed to determine its value in patients under MCS.

Tales from the future-nuclear cardio-oncology, from prediction to diagnosis and monitoring

Cancer and cardiovascular diseases (CVD) often share common risk factors, and patients with CVD who develop cancer are at high risk of experiencing major adverse cardiovascular events. Additionally, cancer treatment can induce short- and long-term adverse cardiovascular events. Given the improvement in oncological patients' prognosis, the burden in this vulnerable population is slowly shifting towards increased cardiovascular mortality. Consequently, the field of cardio-oncology is steadily expanding, prompting the need for new markers to stratify and monitor the cardiovascular risk in oncological patients before, during, and after the completion of treatment. Advanced non-invasive cardiac imaging has raised great interest in the early detection of CVD and cardiotoxicity in oncological patients. Nuclear medicine has long been a pivotal exam to robustly assess and monitor the cardiac function of patients undergoing potentially cardiotoxic chemotherapies. In addition, recent radiotracers have shown great interest in the early detection of cancer-treatment-related cardiotoxicity. In this review, we summarize the current and emerging nuclear cardiology tools that can help identify cardiotoxicity and assess the cardiovascular risk in patients undergoing cancer treatments and discuss the specific role of nuclear cardiology alongside other non-invasive imaging techniques.

Novel Cellular and Immunotherapy: Toxicities and Perioperative Implications

Targeted cellular and immunotherapies have welcomed a new chapter in multi-modal cancer therapy. These agents harness our innate immune system and destroy malignant cells in a precise way as compared with "legacy" chemotherapeutic agents that largely rely on abolishing cell division. New therapies can augment the T-cell recognition of tumor antigens and effectively prevent tumor cells from their historically successful ability to evade immune recognition. These novel agents cause acute and chronic toxicities to a variety of organ systems (enteritis, pneumonitis, hypophysitis, and hepatitis), and this may masquerade as other chronic illnesses or paraneoplastic effects. As the perioperative footprint of cancer patients increases, it is essential that perioperative providers-anesthesiologists, surgeons, nurse anesthetists, and inpatient hospital medicine providers-be up to date on the physiologic mechanisms that underlie these new therapies as well as their acute and subacute toxicity profiles. Immunotherapy toxicity can significantly impact perioperative morbidity as well as influence perioperative management, such as prophylaxis for adrenal insufficiency, preoperative pulmonary assessment, and screening for thyroid dysfunction, among others.

Cardiomuscular Biomarkers in the Diagnosis and Prognostication of Immune Checkpoint Inhibitor Myocarditis

BACKGROUND

Immune checkpoint inhibitors (ICIs) are approved for multiple cancers but can result in ICI-associated myocarditis, an infrequent but life-threatening condition. Elevations in cardiac biomarkers, specifically troponin-I (cTnI), troponin-T (cTnT), and creatine kinase (CK), are used for diagnosis. However, the association between temporal elevations of these biomarkers with disease trajectory and outcomes has not been established.

METHODS

We analyzed the diagnostic accuracy and prognostic performances of cTnI, cTnT, and CK in patients with ICI myocarditis (n=60) through 1-year follow-up in 2 cardio-oncology units (APHP Sorbonne, Paris, France and Heidelberg, Germany). A total of 1751 (1 cTnT assay type), 920 (4 cTnI assay types), and 1191 CK sampling time points were available. Major adverse cardiomyotoxic events (MACE) were defined as heart failure, ventricular arrhythmia, atrioventricular or sinus block requiring pacemaker, respiratory muscle failure requiring mechanical ventilation, and sudden cardiac death. Diagnostic performance of cTnI and cTnT was also assessed in an international ICI myocarditis registry.

RESULTS

Within 72 hours of admission, cTnT, cTnI, and CK were increased compared with upper reference limits (URLs) in 56 of 57 (98%), 37 of 42 ([88%] P=0.03 versus cTnT), and 43 of 57 ([75%] P<0.001 versus cTnT), respectively. This increased rate of positivity for cTnT (93%) versus cTnI ([64%] P<0.001) on admission was confirmed in 87 independent cases from an international registry. In the Franco-German cohort, 24 of 60 (40%) patients developed ≥1 MACE (total, 52; median time to first MACE, 5 [interquartile range, 2-16] days). The highest value of cTnT:URL within the first 72 hours of admission performed best in terms of association with MACE within 90 days (area under the curve, 0.84) than CK:URL (area under the curve, 0.70). A cTnT:URL ≥32 within 72 hours of admission was the best cut-off associated with MACE within 90 days (hazard ratio, 11.1 [95% CI, 3.2-38.0]; P<0.001), after adjustment for age and sex. cTnT was increased in all patients within 72 hours of the first MACE (23 of 23 [100%]), whereas cTnI and CK values were less than the URL in 2 of 19 (11%) and 6 of 22 (27%) of patients (P<0.001), respectively.

CONCLUSIONS

cTnT is associated with MACE and is sensitive for diagnosis and surveillance in patients with ICI myocarditis. A cTnT:URL ratio <32 within 72 hours of diagnosis is associated with a subgroup at low risk for MACE. Potential differences in diagnostic and prognostic performances between cTnT and cTnI as a function of the assays used deserve further evaluation in ICI myocarditis.

Immune checkpoint inhibitor-related myocarditis: current understanding and potential diagnostic and therapeutic strategies

INTRODUCTION

Myocarditis associated with immune checkpoint inhibitors presents with an often-severe clinical phenotype with arrhythmias and concurrent myositis. This condition tends to occur early after treatment onset and is associated with a high fatality rate. Diagnosis may be challenging, and treatment algorithms are still evolving.

AREAS COVERED

This review will provide an overview of immune checkpoint inhibitor mechanism of action and how it relates to myocarditis pathophysiology, diagnostic algorithms and potential pitfalls, and emerging treatment approaches published until May 2023. We will focus on the state of the field and potential new directions in research and patient care. We will also provide consensus-based diagnostic and therapeutic algorithms endorsed by major societies.

EXPERT OPINION

The field needs more evidence-based approaches to risk stratification so that therapy can be tailored toward less cardiotoxic alternatives in high-risk patients. For diagnostic and therapeutic approaches, data from animal models are unlikely to provide conclusive evidence given the complexity of the human immune system. We strongly invite practitioners in the field to contribute every case to the ongoing multicenter registries.

Myocarditis and Autoimmunity

INTRODUCTION

Autoimmune myocarditis may develop due to heterogeneous causes. Myocarditis is often caused by viral infections, but it can also be caused by systemic autoimmune diseases. Immune checkpoint inhibitors and virus vaccines induce immune activation, and they can cause the development of myocarditis, as well as several immune-related adverse events. The development of myocarditis is dependent on the genetic factors of the host, and the major histocompatibility complex (MHC) may be an important determinant of the type and severity of the disease. However, non-MHC immunoregulatory genes may also play a role in determining susceptibility.

AREA COVERED

This review summarizes the current knowledge of the etiology, pathogenesis, diagnosis and treatment of autoimmune myocarditis with a particular focus on viral infection and autoimmunity, and biomarkers of myocarditis.

EXPERT OPINION

An endomyocardial biopsy may not be the gold standard for the diagnosis of myocarditis. Cardiac magnetic resonance imaging is useful in diagnosing autoimmune myocarditis. Recently identified biomarkers of inflammation and myocyte injury are promising for the diagnosis of myocarditis when measured simultaneously. Future treatments should focus on the appropriate diagnosis of the etiologic agent, as well as on the specific stage of the evolution of immune and inflammatory processes.

A Brain, A Heart, and the Courage: Balancing Benefit and Toxicity of Immunotherapy in Melanoma

The overall survival of advanced melanoma has improved dramatically. Immunotherapies, specifically checkpoint inhibitors, have played a large role in this improvement. These agents have also shown benefit in the adjuvant setting, are approved for treatment of resected stage II, III, and IV melanoma, and play an evolving role in the neoadjuvant setting. Although generally well tolerated, immune-related adverse events occur and can be severe. Here we focus on some severe and potentially long term toxicities, including cardiovascular and neurologic toxicities. Our understanding of the acute and long-term toxicities of immune checkpoint inhibitors continues to evolve. Oncologists must continue to balance cancer risk and treatment-related toxicities.

Prognosis of immune checkpoint inhibitors-induced myocarditis: a case series

BACKGROUND

Immune checkpoint inhibitors (ICI) have transformed cancer treatment over the last decade. Alongside this therapeutic improvement, a new variety of side effects has emerged, called immune-related adverse events (irAEs), potentially affecting any organ. Among these irAEs, myocarditis is rare but life-threatening.

METHODS

We conducted a multicenter cross-sectional retrospective study with the aim of better characterizing ICI-related myocarditis. Myocarditis diagnosis was based on the recent consensus statement of the International Cardio-Oncology Society.

RESULTS

Twenty-nine patients were identified, from six different referral centers. Most patients (55%) were treated using anti-programmed-death 1, rather than ICI combination (35%) or anti-programmed-death-ligand 1 (10%). Transthoracic echocardiography was abnormal in 52% of them, and cardiac magnetic resonance showed abnormal features in 14/24 patients (58%). Eleven patients (38%) were classified as severe. Compared with other patients, they had more frequently pre-existing systemic autoimmune disease (45% vs 6%, p=0.018), higher troponin level on admission (42-fold the upper limit vs 3.55-fold, p=0.001), and exhibited anti-acetylcholine receptor autoantibodies (p=0.001). Seven patients (24%) had myocarditis-related death, and eight more patients died from cancer progression during follow-up. Twenty-eight patients received glucocorticoids, 10 underwent plasma exchanges, 8 received intravenous immunoglobulins, and 5 other immunosuppressants. ICI rechallenge was performed in six patients, with only one myocarditis relapse.

DISCUSSION

The management of ICI-related myocarditis may be challenging and requires a multidisciplinary approach. Prognostic features are herein described and may help to allow ICI rechallenge for some patients with smoldering presentation, after an accurate evaluation of benefit-risk balance.