Radiation-Associated Pericardial Disease

NADPH Oxidases in Cancer Therapy-Induced Cardiotoxicity: Mechanisms and Therapeutic Approaches

Cancer therapy-induced cardiotoxicity remains a significant clinical challenge, limiting the efficacy of cancer treatments and impacting long-term survival and quality of life. NADPH oxidases, a family of enzymes that are able to generate reactive oxygen species (ROS), have emerged as key players in the pathogenesis of cardiotoxicity associated with various cancer therapies. This review comprehensively examines the role of NADPH oxidases in cancer therapy-induced cardiotoxicity, elucidating the underlying mechanisms and exploring potential therapeutic approaches. We discuss the structure and function of NADPH oxidases in the cardiovascular system and their involvement in cardiotoxicity induced by anthracyclines and ionizing radiation. The molecular mechanisms by which NADPH oxidase-derived ROS contribute to cardiac injury are explored, including direct oxidative damage, activation of pro-apoptotic pathways, mitochondrial dysfunction, vascular damage, inflammation, fibrosis, and others. Furthermore, we evaluate therapeutic strategies targeting NADPH oxidases, such as specific inhibitors, antioxidant therapies, natural products, and other cardioprotectors. The review also addresses current challenges in the field, including the need for isoform-specific targeting and the identification of reliable biomarkers. Finally, we highlight future research directions aimed at mitigating NADPH oxidase-mediated cardiotoxicity and alleviating cardiovascular side effects in cancer survivors. By synthesizing current knowledge and identifying knowledge gaps, this review provides a rationale for future studies and the development of novel cardioprotective strategies in cancer therapy.

Imaging of the Acute and Chronic Cardiovascular Complications of Radiation Therapy

Chest radiotherapy (XRT) plays a crucial role in the treatment of a multitude of cancers including breast, lung, esophageal, and lymphoma. Although XRT enhances cancer survival rates, it may also expose healthy bystander tissues to radiation, potentially leading to severe complications. Initially considered relatively resistant to radiation damage, the heart has been shown over the past 4 decades to be susceptible to radiation-induced cardiovascular toxicity and despite advances in XRT which can minimize radiation exposure to heart tissue, no cardiac radiation dose is entirely safe. The clinical spectrum of radiation-induced cardiovascular toxicity is broad, encompassing coronary artery disease, myocardial dysfunction, valvular abnormalities, and pericardial disorders. Radiation-induced cardiovascular toxicity may manifest acutely or many years after XRT, with each condition more likely to present at certain time points post-XRT. Cardiac imaging is a crucial tool in both the screening and diagnosis of radiation-induced cardiovascular toxicity with an understanding of its pathophysiology, incidence, and progression required to implement a comprehensive, multimodality imaging approach to detect and manage these complications effectively.

Cardiac Complications of Radiation Therapy

Radiation therapy is a critical component in managing many malignancies by improving local control and survival. The benefits of radiation may come at the expense of unintended radiation injury to the surrounding normal tissues, with the heart being one of the most affected organs in thoracic radiation treatments. As cancer survivors live longer, radiation-induced cardiotoxicity (RICT) is now increasingly recognized. In this review, we highlight the spectrum and pathophysiology of RICT. We summarize contemporary recommendations for risk stratification, screening, prevention, and management of RICT. We briefly highlight novel applications for radiation to treat some cardiac conditions such as resistant arrhythmias.

Consequences of ionizing radiation exposure to the cardiovascular system

Ionizing radiation is widely used in various industrial and medical applications, resulting in increased exposure for certain populations. Lessons from radiation accidents and occupational exposure have highlighted the cardiovascular and cerebrovascular risks associated with radiation exposure. In addition, radiation therapy for cancer has been linked to numerous cardiovascular complications, depending on the distribution of the dose by volume in the heart and other relevant target tissues in the circulatory system. The manifestation of symptoms is influenced by numerous factors, and distinct cardiac complications have previously been observed in different groups of patients with cancer undergoing radiation therapy. However, in contemporary radiation therapy, advances in treatment planning with conformal radiation delivery have markedly reduced the mean heart dose and volume of exposure, and these variables are therefore no longer sole surrogates for predicting the risk of specific types of heart disease. Nevertheless, certain cardiac substructures remain vulnerable to radiation exposure, necessitating close monitoring. In this Review, we provide a comprehensive overview of the consequences of radiation exposure on the cardiovascular system, drawing insights from various cohorts exposed to uniform, whole-body radiation or to partial-body irradiation, and identify potential risk modifiers in the development of radiation-associated cardiovascular disease.

Patients with metastatic cancer have worse short-term coronary artery bypass grafting outcomes: A population-based study of National Inpatient Sample from 2015 to 2020

BACKGROUND

Metastasis is a hallmark for cancer progression. While patients with metastatic cancer (MC) have higher risk profiles, outcomes of coronary artery bypass grafting (CABG) in these patients have not been established, likely due to their smaller representation in the CABG patient population. This study aimed to examine the short-term outcomes of patients with MC who underwent CABG.

METHODS

Patients who underwent CABG were identified in National Inpatient Sample from Q4 2015-2020. Exclusion criteria included age <18 years, concomitant procedures, and non-metastatic malignancies. A 1:3 propensity-score matching was used to address differences in demographics, socioeconomic status, primary payer status, hospital characteristics, comorbidities, and transfer/admission status between MC and non-MCC patients. In-hospital post-CABG outcomes were evaluated.

RESULTS

There were 379 (0.23 %) patients with MC who underwent CABG. All MC patients were matched to 1161 out of 164,351 non-MC patients who underwent CABG during the same period. Patients with MC had higher risks of mortality (4.76 % vs 2.58 %, p = 0.04), pacemaker implantation (2.91 % vs 1.12 %, p = 0.03), venous thromboembolism (1.85 % vs 0.43 %, p = 0.01), and hemorrhage/hematoma (61.11 % vs 55.04 %, p = 0.04). In addition, MC patients had a longer time from admission to operation (3.35 ± 4.19 vs 2.82 ± 3.54 days, p = 0.03) and longer hospital length of stay (11.86 ± 8.17 vs 10.65 ± 8.08 days, p = 0.01).

CONCLUSION

Patients with MC had higher short-term mortality and morbidities after CABG. These findings can help provide insights for clinicians in the management of patients with concurrent coronary artery disease and MC, particularly in terms of preoperative risk stratification and therapeutic decision-making.

Cardio-oncology concerns in radiotherapy: Heart and cardiac substructure toxicities from modern delivery techniques

Cardio-oncology is lately gaining more attention due to radiation-induced cardiac events reported by a very large number of studies. In view of this, the current overview of the literature aimed to encompass all studies from the past 15 years to assess changes in cardiac dose due to treatment evolution, as well as the changes in treatment planning customs to incorporate not only the heart as a whole but also cardiac substructures. Modern treatment techniques, particularly proton therapy, offers superior cardiac sparing compared to more established radiotherapy, for all evaluated tumor sites. Intensity modulation, particularly coupled with respiratory gating shows significant improvement in dose-volume parameters pertaining to the heart. While past studies considered mean heart dose as the only reference for cardiac toxicities, recommendations for the other cardiac substructures to be dosimetrically assessed during planning are becoming more common.

Cardiovascular toxicity in antitumor therapy: biological and therapeutic insights

The evolution of antitumor therapies has significantly improved cancer prognosis but has concurrently resulted in cardiovascular toxicities. Understanding the biological mechanisms behind these toxicities is crucial for effective management. Immunotherapy-related cardiovascular toxicities are primarily mediated by immune cells and secreted cytokines. Chemotherapy may cause cardiovascular damage through autophagy disruption and mitochondrial dysfunction. Targeted therapies can induce toxicity through endothelin-1 (ET-1) production and cardiac signaling disruption. Radiotherapy may lead to cardiomyopathy and myocardial fibrosis by affecting endothelial cells, triggering inflammatory responses and accelerating atherosclerosis. This review provides insights into these mechanisms and strategies, aiming to enhance the clinical prevention and treatment of cardiovascular toxicities.

Case Report: Spontaneous acute hemopericardium

Acute hemopericardium is generally produced by complications of interventional procedures or traumatisms to the chest wall. In absence of those antecedents, clinicians face an arduous process of etiological diagnosis and treatment. We present the case of a male patient with history of Hodgkin's lymphoma and aortic endovascular treatment years ago, who develop an episode of fever, chest pain and dyspnea that was complicated with cardiac tamponade diagnosed with echocardiogram and angio- tomography. In the operating room hemopericardium was diagnosed and drained with resolution of symptoms. Diagnosis work out was carried out with suspicion of tuberculous or neoplastic pericarditis with negative results. Patient was discharged with the diagnoses of viral or idiopathic pericarditis. The case highlights the use of multimodality images and laboratories procedures to lead to a correct diagnoses and treatment.

Radiation-associated cardiovascular disease in patients with cancer: current insights from a cardio-oncologist

Radiation-associated cardiovascular disease (RACD), a complex disease characterized with pericarditis, myocardial damage, valvular heart diseases, heart failure, vasculopathy and ischemic heart disease, has a generally poor prognosis. While RACD may be acute, it often manifests in the late years or even decades following radiation exposure to the chest. With an increasing number of cancer survivors, RACD is likely to become an important issue in cardio-oncology. This review discusses pre-radiation therapy (RT) preparation, peri-RT patient management and long follow-up planning post-RT from a cardiology perspective. Additionally, a novel technique of stereotactic radiotherapy, which has been applied for the treatment of intractable cardiac arrhythmias, is presented. Appropriate patient examination and management during and after RT are essential to support patients undergoing cancer treatment to improve long life expectancy. A multidisciplinary team is needed to determine how to manage patients who receive RT to reduce RACD, to detect early phases of RACD and to provide the best treatment for RACD. Recent studies increasingly report advances in diagnosis using new equipment that has the potential to detect early phases of RACD, along with growing evidence for the optimal treatment for RACD. This review provides an overview of recent studies and guidelines to report on the latest findings, and to identify unresolved issues surrounding RACD that require validation in future studies.

Cardiac surgery for radiation associated heart disease in Hodgkin lymphoma patients

Much of the modern focus of Hodgkin's Lymphoma (HL) treatment involves the prevention of secondary organ injury. Despite rationalisations of radiotherapy fields, many patients still develop late radiation-related cardiotoxicity that is severe and requires interventional management. No guidelines exist to direct management of these complex patients who often present with multiple concurrent cardiac pathologies. Despite possessing a greater mortality risk than in the general population, cardiac surgery has an important role in treating radiation-associated heart disease. This review summarises the body of literature surrounding cardiac surgery in HL survivors post-radiotherapy, highlighting the benefits and risks unique to this cohort. The pathophysiology and presentation of radiation-associated heart disease is also explored in relation to HL patients.

The role of cardiac surgery in radiation-associated heart disease: a scoping review

BACKGROUND

Thoracic irradiation is an important tool in the treatment of breast cancer, non-Hodgkin's lymphoma, and other cancers of the chest. The heart is commonly involved in these radiation fields, and young patients can present with severe cardiac pathologies requiring surgical intervention. However, this population poses a high surgical risk due to involvement of mediastinal tissues, and there are no consensus guidelines on best practice management.

AIM

This review aims to summarise the current experience of surgical correction of radiation-associated heart disease. We explore outcomes, technique modifications and alternative therapies for the three primary procedures performed: coronary artery bypass grafting, valvular intervention and pericardiectomy.

METHODS

OVID Medline and PubMed databases were comprehensively searched to identify all studies involving surgery in patients with prior chest radiotherapy. All relevant studies within the past 25 years have been discussed.

CONCLUSION

Irradiated patients have heightened peri-operative risk, but other than redo surgery, these operations are not as treacherous as once thought. Involvement of all layers of the heart, especially the myocardium, is such that long-term mortality suffers despite optimal surgical correction. The goal of surgery in this cohort should be for a quick and safe operation, rather than a technically difficult procedure aimed at longevity.

Radiation-Induced Pericardial Disease: Mechanisms, Diagnosis, and Treatment

PURPOSE OF REVIEW

We aim to give a concise overview of the different clinical manifestations of both acute and long-term radiotherapy-related pericardial diseases, the underlying pathophysiology as well as the diagnosis and treatment options.

RECENT FINDINGS

Radiotherapy-related pericardial disease is common, but despite radiotherapy being a cornerstone of many cancer treatments, this disease entity is relatively underrepresented in clinical trials, resulting in a paucity of research data on pathophysiology and management. Since the development of innovative cancer treatments, survival has significantly improved. Therefore, the importance of long-term treatment-related side effects increases, most notably cancer treatment-related cardiovascular toxicity. In patients undergoing radiotherapy as a part of their cancer treatment, radiotherapy-related pericardial disease can manifest early (during or shortly after radiotherapy administration) or very late (several years to decades after treatment). This exceptionally long latency period confronts physicians with treatment-related side effects of radiotherapy regimens that may have been abandoned already.

Uncommon short- and long-term cardiological side effects of thoracic radiation: a report of two cases

Radiotherapy is an essential treatment of more than 50% of oncohematological patients. Pericardial disorders and valvular heart disease are two common radiotherapy complications. Acute pericarditis is infrequent and usually underdiagnosed. Therefore, diagnostic suspicion and early treatment are mandatory to avoid the evolution to constrictive pericarditis. The prevalence of radiation-induced valvular heart disease is common in patients with a history of Hodgkin's lymphoma and breast cancer. It has distinctive characteristics from other etiologies and, thus, different therapeutic approaches. We present two cases of unusual complications of radiotherapy; the first one in the acute setting and the second one during the follow-up in the chronic phase. A multidisciplinary and individualized approach with specific considerations is decisive in the management of these patients.

Mean heart dose-based normal tissue complication probability model for pericardial effusion: a study in oesophageal cancer patients

We investigated the normal tissue complication probability (NTCP) of the incidence of pericardial effusion (PCE) based on the mean heart dose (MHD) in patients with oesophageal cancer treated with definitive chemoradiotherapy. The incidences of PCE in any grade (A-PCE) and symptomatic PCE (S-PCE) were evaluated separately. To identify predictors for PCE, several clinical and dose-volume parameters were analysed using a receiver operating characteristic (ROC) curve and multivariate regression analysis. To validate its clinical applicability, the generated NTCP model was compared to the Lyman–Kutcher–Burman (LKB) model. Among 229 eligible patients, A-PCE and S-PCE were observed in 100 (43.7%) and 18 (7.9%) patients, respectively. MHD showed a preferable area under the curve (AUC) value for S-PCE (AUC = 0.821) and A-PCE (AUC = 0.734). MHD was the only significant predictor for A-PCE; MHD and hypertension were selected as significant factors for S-PCE. The estimated NTCP, using the MHD-based model, showed excellent correspondence to the LKB model in A-PCE and S-PCE. The NTCP curve of A-PCE was gentler than that of S-PCE and had no threshold. The MHD-based NTCP model was simple but comparable to the LKB model for both A-PCE and S-PCE. Therefore, the estimated NTCP may provide clinically useful parameters for predicting PCE.

DNA damage response in vascular endothelial senescence: Implication for radiation-induced cardiovascular diseases

A post-exposure cohort study in Hiroshima and Nagasaki reported that low-dose exposure to radiation heightened the risk of cardiovascular diseases (CVD), such as stroke and myocardial infarction, by 14-18% per Gy. Moreover, the risk of atherosclerosis in the coronary arteries reportedly increases with radiation therapy of the chest, including breast and lung cancer treatment. Cellular senescence of vascular endothelial cells (ECs) is believed to play an important role in radiation-induced CVDs. The molecular mechanism of age-related cellular senescence is believed to involve genomic instability and DNA damage response (DDR); the chronic inflammation associated with senescence causes cardiovascular damage. Therefore, vascular endothelial cell senescence is believed to induce the pathogenesis of CVDs after radiation exposure. The findings of several prior studies have revealed that ionizing radiation (IR) induces cellular senescence as well as cell death in ECs. We have previously reported that DDR activates endothelial nitric oxide (NO) synthase, and NO production promotes endothelial senescence. Endothelial NO synthase (eNOS) is a major isoform expressed in ECs that maintains cardiovascular homeostasis. Therefore, radiation-induced NO production, a component of the DDR in ECs, may be involved in CVDs after radiation exposure. In this article, we describe the pathology of radiation-induced CVD and the unique radio-response to radiation exposure in ECs.

Mechanisms and clinical manifestations of cardiovascular toxicities associated with immune checkpoint inhibitors

Immunotherapies have greatly expanded the armamentarium of cancer-directed therapies in the past decade, allowing the immune system to recognize and fight cancer. Immune checkpoint inhibitors (ICIs), in particular, have revolutionized cancer treatment and have demonstrated survival benefit in numerous types of cancer. These monoclonal antibodies increase anti-cancer immunity by blocking down-regulators of adaptive immunity, including cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), and its ligand (PD-L1), resulting in anti-tumor activity. As ICIs increase immune system activation, they can cause a wide range of inflammatory side effects, termed immune-released adverse events. Though these toxicities can affect nearly any organ, the most fatal toxicity is myocarditis. Here, we discuss the diverse spectrum of cardiovascular toxicities associated with ICI use. In addition, we provide insight and future directions on mechanisms and treatments for immune-related adverse events (irAEs) involving the myocardium, pericardium, vasculature, and conduction system.

Chronic massive pericardial effusion: a case report and literature review

Chronic massive pericardial effusion without cardiac tamponade is relatively rare. Nearly half of all patients with chronic large pericardial effusion are asymptomatic. We report a case of a 77-year-old man who presented with an asymptomatic chronic massive pericardial effusion, with no evidence of cardiac tamponade or pericardial constriction during a 10-year follow-up. The patient had a complex history of lymph node tuberculosis, hypertension, hypothyroidism, and polycythemia vera, as well as high-dose ³¹P radiation exposure 45 years ago. There was no evidence of tuberculosis infection, hypothyroidism, malignant tumor, severe heart failure, uremia, trauma, severe bacterial or fungal infection, chronic myeloid leukemia, or bone marrow fibrosis after admission. The patient underwent pericardiocentesis twice. The pericardial effusion comprised exudate fluid with a high proportion of monocytes. The patient refused indwelling catheter drainage or pericardiectomy. The likely final diagnosis was recurrent chronic large idiopathic pericardial effusion.

At What Dose Can Total Body and Whole Abdominal Irradiation Cause Lethal Intestinal Injury Among C57BL/6J Mice?

PURPOSE AND METHODS

To investigate the doses of total body (TBI) and whole abdominal irradiation (WAI) induced lethal intestinal injury, healthy C57BL/6 J mice were divided randomly into 7 groups: control group; 6, 7, and 8 Gy TBI groups; and 5, 10, and 15 Gy WAI groups. The survival length, general conditions, body weight, daily food and water intake of the mice and the histopathological changes of small intestine were observed.

RESULTS

Lethal injury among C57BL/6 J mice was caused by ≥6 Gy TBI and 15 Gy WAI. Their body weight and food intake decreased, the structure of their small intestinal villi was destroyed, and the number of surviving crypts per circumference of the jejunum decreased in ≥6 Gy TBI groups and 15 Gy WAI group. The mice in the 10 Gy WAI group significantly lost weight within 5 days but recovered slowly thereafter. They also had poor appetite and reversibly damaged intestinal mucosa.

CONCLUSIONS

Nonlethal intestinal injury could be induced by 10 Gy WAI, whereas lethal intestinal injury could be triggered by ≥6 Gy TBI and >15 Gy WAI in mice. Our results provided a basis for establishing radiation-induced intestinal injury models with C57BL/6 J mice.

Cancer Treatment-Associated Pericardial Disease: Epidemiology, Clinical Presentation, Diagnosis, and Management

PURPOSE OF REVIEW

Cancer therapeutics have seen tremendous growth in the last decade and have been effective in the treatment of several cancer types. However, with advanced therapies like kinase inhibitors and immunotherapies, there have been unintended consequences of cardiotoxicities. While traditional chemotherapy and radiation-induced cardiotoxicity have been well studied, further research is needed to understand the adverse effects of newer regimens.

RECENT FINDINGS

Both immune-mediated and non-immune-medicated cytotoxicity have been noted with targeted therapies such as tyrosine kinase inhibitors and immune checkpoint inhibitors. In this manuscript, we describe the pericardial syndromes associated with cancer therapies and propose management strategies. Pericardial effusion and pericarditis are common presentations in cancer patients and often difficult to diagnose. Concomitant myocarditis may also present with pericardial toxicity, especially with immunotherapies. In addition to proper history and physical, additional testing such as cardiovascular imaging and tissue histology need to be obtained as appropriate. Holding the offending oncology drug, and institution of anti-inflammatory medications, and immunosuppressants such as steroids are indicated. A high index of suspicion, use of standardized definitions, and comprehensive evaluation are needed for early identification, appropriate treatment, and better outcomes for patients with cancer treatment-associated pericardial disease. Further research is needed to understand the pathophysiology and to evaluate how the management of pericardial conditions in these patients differ from traditional management and also evaluate new therapies.