Long-Term Mortality in Patients With Radiation-Associated Coronary Artery Disease Treated With Percutaneous Coronary Intervention

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.

Mortality After Major Cardiovascular Events in Survivors of Childhood Cancer

BACKGROUND

Adult survivors of childhood cancer are at risk for cardiovascular events.

OBJECTIVES

In this study, we sought to determine the risk for mortality after a major cardiovascular event among childhood cancer survivors compared with noncancer populations.

METHODS

All-cause and cardiovascular cause-specific mortality risks after heart failure (HF), coronary artery disease (CAD), or stroke were compared among survivors and siblings in the Childhood Cancer Survivor Study (CCSS) and participants in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Cox proportional hazard regression models were used to estimate HRs and 95% CIs between groups, adjusted for demographic and clinical factors.

RESULTS

Among 25,658 childhood cancer survivors (median age at diagnosis 7 years, median age at follow-up or death 38 years) and 5,051 siblings, 1,780 survivors and 91 siblings had a cardiovascular event. After HF, CAD, and stroke, 10-year all-cause mortalities were 30% (95% CI: 26%-33%), 36% (95% CI: 31%-40%), and 29% (95% CI: 24%-33%), respectively, among survivors vs 14% (95% CI: 0%-25%), 14% (95% CI: 2%-25%), and 4% (95% CI: 0%-11%) among siblings. All-cause mortality risks among childhood cancer survivors were increased after HF (HR: 7.32; 95% CI: 2.56-20.89), CAD (HR: 5.54; 95% CI: 2.37-12.93), and stroke (HR: 3.57; 95% CI: 1.12-11.37). CAD-specific mortality risk was increased (HR: 3.70; 95% CI: 1.05-13.02). Among 5,114 CARDIA participants, 345 had a major event. Although CARDIA participants were on average decades older at events (median age 57 years vs 31 years), mortality risks were similar, except that all-cause mortality after CAD was significantly increased among childhood cancer survivors (HR: 1.85; 95% CI: 1.16-2.95).

CONCLUSIONS

Survivors of childhood cancer represent a population at high risk for mortality after major cardiovascular events.

Interventional cardiology in cancer patients: A position paper from the Portuguese Cardiovascular Intervention Association and the Portuguese Cardio-Oncology Study Group of the Portuguese Society of Cardiology

The field of Cardio-Oncology has grown significantly, especially during the last decade. While awareness of cardiotoxicity due to cancer disease and/or therapies has greatly increased, much of the attention has focused on myocardial systolic disfunction and heart failure. However, coronary and structural heart disease are also a common issue in cancer patients and encompass the full spectrum of cardiotoxicity. While invasive percutaneous or surgical intervention, either is often needed or considered in cancer patients, limited evidence or guidelines are available for dealing with coronary or structural heart disease. The Society for Cardiovascular Angiography and Interventions consensus document published in 2016 is the most comprehensive document regarding this particular issue, but relevant evidence has emerged since, which render some of its considerations outdated. In addition to that, the recent 2022 ESC Guidelines on Cardio-Oncology only briefly discuss this topic. As a result, the Portuguese Association of Cardiovascular Intervention and the Cardio-Oncology Study Group of the Portuguese Society of Cardiology have partnered to produce a position paper to address the issue of cardiac intervention in cancer patients, focusing on percutaneous techniques. A brief review of available evidence is provided, followed by practical considerations. These are based both on the literature as well as accumulated experience with these types of patients, as the authors are either interventional cardiologists, cardiologists with experience in the field of Cardio-Oncology, or both.

Percutaneous Coronary Intervention Mortality, Cost, Complications, and Disparities after Radiation Therapy: Artificial Intelligence-Augmented, Cost Effectiveness, and Computational Ethical Analysis

The optimal cardio-oncology management of radiation therapy and its complications are unknown despite the high patient and societal costs. This study is the first known nationally representative, multi-year, artificial intelligence and propensity score-augmented causal clinical inference and computational ethical and policy analysis of percutaneous coronary intervention (PCI) mortality, cost, and disparities including by primary malignancy following radiation therapy. Bayesian Machine learning-augmented Propensity Score translational (BAM-PS) statistics were conducted in the 2016-2020 National Inpatient Sample. Of the 148,755,036 adult hospitalizations, 2,229,285 (1.50%) had a history of radiation therapy, of whom, 67,450 (3.00%) had an inpatient AMI, and of whom, 18,400 (28.69%) underwent PCI. Post-AMI mortality, costs, and complications were comparable with and without radiation across cancers in general and across the 30 primary malignancies tested, except for breast cancer, in which PCI significantly increased mortality (OR 3.70, 95%CI 1.10-12.43, p = 0.035). In addition to significant sex, race, and insurance disparities, significant regional disparities were associated with nearly 50 extra inpatient deaths and over USD 500 million lost. This large clinical, cost, and pluralistic ethical analysis suggests PCI when clinically indicated should be provided to patients regardless of sex, race, insurance, or region to generate significant improvements in population health, cost savings, and social equity.

Accelerated Atherosclerosis and Cardiovascular Toxicity Induced by Radiotherapy in Breast Cancer

The number of patients diagnosed with breast cancer and cardiovascular disease is continuously rising. Treatment options for breast cancer have greatly evolved, but radiotherapy (RT) still has a key role in it. Despite many advances in RT techniques, cardiotoxicity is one of the most important side effects. The new cardio-oncology guidelines recommend a baseline evaluation, risk stratification and follow-up of these patients. Cardiotoxicity induced by RT can be represented by almost all forms of cardiovascular disease, with atherosclerosis being the most frequent. An interdisciplinary team should manage these patients, in order to have maximum therapeutic effect and minimum cardiovascular toxicity. This review will summarize the current incidence, risk factors, mechanisms and follow-up of RT-induced cardiovascular toxicity.

Mitigating, monitoring, and managing long-term chemotherapy- and radiation-induced cardiac toxicity

Five-year survival for childhood cancer now exceeds 85%. However, for many patients, treatment requires the use of intensive anthracycline-based chemotherapy and radiotherapy, both of which are associated with significant long-term cardiovascular toxicity. As such, late cardiovascular disease is now one of the leading causes of premature morbidity and mortality among childhood cancer survivors. Recent advances over the past decade have refined the cardiotoxic potential of various chemotherapeutics, and ongoing work seeks to determine the efficacy of various cardioprotective strategies in children receiving active cancer therapy. The development of risk prediction models offers an additional strategy to define risk for both newly treated and long-term survivors. Current screening strategies are primarily based on echocardiography, although there is active research investigating methods to further optimize screening through myocardial strain, cardiac magnetic resonance imaging, blood biomarkers, and genetics, along with the cost-effectiveness of different screening strategies. Active research is also underway investigating the efficacy of prevention strategies for childhood cancer survivors who have completed cancer therapy. This ranges from the use of medications to mitigate potential pathologic ventricular remodeling to reducing adverse and modifiable cardiovascular risk factors (eg, hypertension, dyslipidemia, insulin resistance, physical inactivity, tobacco exposure), many of which may be more common in cancer survivors vs the general population and are often underrecognized and undertreated in relatively young adult-aged survivors of childhood cancer.

Percutaneous Coronary Intervention Outcomes in Patients With Prior Thoracic Radiation Therapy: A Systematic Review and Meta-Analysis

Background

Thoracic radiation predisposes patients to accelerated coronary artery disease. There is a paucity of data in both short-term and long-term outcomes following revascularization in patients who have undergone thoracic radiation.

Methods

We performed a search of the Medline, Cochrane, and Scopus databases for studies that compared outcomes in cancer patients who have undergone thoracic radiation and percutaneous coronary intervention (PCI). The primary outcome of our meta-analysis was all-cause mortality. Secondary outcomes included cardiac mortality, myocardial infarction (MI), and restenosis.

Results

The analysis included four observational studies with a total of 13,941 patients for the primary outcome of all-cause mortality. There were a total of 1,322 patients analyzed for cardiac mortality, 13,103 for MI, and 10,530 for restenosis. The longest follow-up for the primary outcome was 16 years. There was statistically significant higher risk of all-cause mortality in patients who underwent thoracic radiation (risk ratio (RR): 1.29, 95% confidence interval (CI): 1.08 - 1.54, P = 0.004). There was no statistically significant difference in cardiac mortality (RR: 1.15, 95% CI: 0.83 - 1.61, P = 0.40), MI (RR: 1.01, 95% CI: 0.20 - 5.08, P = 0.99), and restenosis (RR: 1.92, 95% CI: 0.24 - 15.35, P = 0.54).

Conclusion

In this meta-analysis, we found a higher risk of all-cause mortality in patients with a history of thoracic radiation undergoing PCI, likely from underlying malignancy itself.

Radiation-Induced Cardiovascular Disease: Mechanisms, Prevention, and Treatment

PURPOSE OF REVIEW

Despite the advancements of modern radiotherapy, radiation-induced cardiovascular disease (RICVD) remains a common cause of morbidity and mortality among cancer survivors.

RECENT FINDINGS

Proposed pathogenetic mechanisms of RICVD include endothelial cell damage with accelerated atherosclerosis, pro-thrombotic alterations in the coagulation pathway as well as inflammation and fibrosis of the myocardial, pericardial, valvular, and conduction tissues. Prevention of RICVD can be achieved by minimizing the exposure of the cardiovascular system to radiation, by treatment of underlying cardiovascular risk factors and cardiovascular disease, and possibly by prophylactic pharmacotherapy post exposure. Herein we summarize current knowledge on the mechanisms underlying the pathogenesis of RICVD and propose prevention and treatment strategies.

Cardiologic Long-Term Follow-Up of Patients Treated With Chest Radiotherapy: When and How?

Introduction: Radiotherapy may cause valvular (VHD), pericardial, coronary artery disease (CAD), left ventricular dysfunction (LVD), arrhythmias. The risk of radiation induced heart disease (RIHD) increases over time. The current guidelines suggest a screening for RIHD every 5 years in the long-term survivors who had been treated by chest RT.

Methods: We reviewed the clinical and instrumental data of 106 patients diagnosed with RIHD. In one group (Group A: 69 patients) RIHD was diagnosed in an asymptomatic phase through a screening with ECG, echocardiogram and stress test. A second group (37 patients) was seen when RIHD was symptomatic. We compared the characteristics of the two groups at the time of RT, of RIHD detection and at last follow-up.

Results: Overall, 64 patients (60%) had CAD (associated to other RIHD in 18); 39 (36.7%) had LVD (isolated in 20); 24 (22.6%) had VHD (isolated in 10 cases). The interval between the last negative test and the diagnosis of moderate or severe RIHD was <5 years in 26 patients, and <4 years in 18. In group A, 63% of the patients with CAD had silent ischemia. The two groups did not differ with regard to type of tumor, cardiovascular risk factors, use of anthracycline-based chemotherapy, age at RT treatment, radiation dose and interval between RT and toxicity detection. The mean time from RT and RIHD was 16 years in group A and 15 in group B. Interventional therapy at RIHD diagnosis was more frequent in group B (54 vs. 30%, p < 0.05). At last follow-up, 27 patients had died (12 of cancer, 9 of cardiac causes, 6 of other causes); mean ejection fraction was 60% in group A and 50% in group B (p < 0.01). Patients with ejection fraction ≤ 50% were 14.5% in group A and 40% in group B (p < 0.01).

Conclusions: Clinically relevant RIHD become evident at a mean interval of 16 years after RT. The most frequent clinical manifestations are CAD and LVD. RIHD diagnosis in asymptomatic patients may preserve their cardiac function with timely interventions. We suggest -after 10 years from radiotherapy- a screening every 2–3 years.

Radiation-Induced Cardiovascular Disease: Review of an Underrecognized Pathology

Radiation therapy demonstrates a clear survival benefit in the treatment of several malignancies. However, cancer survivors can develop a wide array of cardiotoxic complications related to radiation. This pathology is often underrecognized by clinicians and there is little known on how to manage this population. Radiation causes fibrosis of all components of the heart and significantly increases the risk of coronary artery disease, cardiomyopathy, valvulopathy, arrhythmias, and pericardial disease. Physicians should treat other cardiovascular risk factors aggressively in this population and guidelines suggest obtaining regular imaging once symptomatology is established. Patients with radiation‐induced cardiovascular disease tend to do worse than their traditional counterparts for the same interventions. However, there is a trend toward fewer complications and lower mortality with catheter‐based rather than surgical approaches, likely because radiation makes these patients poor surgical candidates. When appropriate, these patients should be referred for percutaneous management of valvulopathy and coronary disease.

Modern Radiotherapy and Risk of Cardiotoxicity

Despite the advancements of modern radiotherapy, radiation-induced heart disease remains a common cause of morbidity and mortality amongst cancer survivors. This review outlines the basic mechanism, clinical presentation, risk stratification, early detection, possible mitigation, and treatment of this condition.

Contemporary Understandings of Cardiovascular Disease After Cancer Radiotherapy: a Focus on Ischemic Heart Disease

PURPOSE OF REVIEW

Radiation-induced cardiovascular disease, including coronary artery disease, is a well-known sequela of radiation therapy and represents a significant source of morbidity and mortality for cancer survivors. This review examines current literature and guidelines to care for this growing population of cancer survivors.

RECENT FINDINGS

The development of radiation-induced ischemic heart disease following radiation can lead even to early cardiotoxicities, inclusive of coronary artery disease, which limit cancer treatment outcomes. These coronary lesions tend to be diffuse, complex, and proximal. Early detection with multimodality imaging and targeted intervention is required to minimize these risks. Early awareness, detection, and management of radiation-induced cardiovascular disease are paramount as cancer survivorship continues to grow.

Outcomes after transcatheter aortic valve replacement in cancer survivors with prior chest radiation therapy: a systematic review and meta-analysis

Background

Cancer survivors with prior chest radiation therapy (C-XRT) frequently present with aortic stenosis (AS) as the first manifestation of radiation-induced heart disease. They are considered high-risk for surgical valve replacement. Transcatheter aortic valve replacement (TAVR) is as an attractive option for this patient population but the outcomes are not well established in major clinical trials. The authors performed a systemic review and meta-analysis of clinical studies for the outcomes after TAVR in cancer survivors with prior C-XRT.

Methods

Online databases were searched from inception to April 2020 for studies evaluating the outcomes of TAVR in patients with and without C-XRT. We analyzed the pooled estimates (with their 95% confidence intervals) of the odds ratio (OR) for the all-cause mortality at 30-day and 1-year follow-ups, 4-point safety outcomes (stroke, major bleed, access-related vascular complications and need for a pacemaker), a 2-point efficacy outcome (mean aortic valve gradient and left ventricular ejection fraction) and worsening of congestive heart failure (CHF). Four studies were included following 2054 patients with and without prior C-XRT exposure (164 patients and 1890 patients respectively).

Results

The C-XRT group had similar 30-day mortality compared to the control group (OR 1.29, 95% CI 0.64 to 2.58, p = 0.48). The 1-year mortality was higher in the C-XRT group (OR 1.97, CI 1.15 to 3.39, p = 0.01). Apart from higher congestive heart failure (CHF) exacerbation in the C-XRT group (OR 2.03, CI 1.36 to 3.04, p = 0.0006), TAVR resulted in similar safety and efficacy outcomes in both groups.

Conclusion

TAVR in the C-XRT group has similar 30-day mortality, safety, and efficacy outcomes compared to the control group; however, they have higher 1-year mortality and CHF exacerbation. Including an oncologist to the cardiology team who considers cancer stage in the decision-making process and applying additional preoperative scores such as frailty indices may refine the risk assessment for these patients. The quality of analyzed data is modest, warranting randomized trials to assess the true benefits of TAVR in these patients.

Acute coronary syndromes in cancer patients

: Cardiovascular disease and cancer are responsible for the majority of deaths in the Western world. These two entities share common risk factors and their intersection will be more and more frequent in future due to general population aging and long-term cancer control. Clinical presentation, management and outcome of acute coronary syndromes (ACS) in cancer patients could differ from noncancer ones. Cancer patients were frequently excluded from clinical trials and so the paucity of data further complicates the scenario. The management of ACS in cancer patients represents a unique setting in which the risk/benefit ratio of invasive treatment should be carefully evaluated. This review focused on the available evidence of all aspects of ACS in cancer patients providing a guide to a multidisciplinary approach.

Radiation-Induced Left Main Coronary Artery Stenosis in a Patient with Atretic Internal Mammary Arteries

Coronary artery disease (CAD) is a known potential complication of thoracic radiation treatment that typically affects the proximal segments of the coronary arteries, requiring coronary artery bypass grafting (CABG). We present a case of acute coronary syndrome occurring in a 57-year-old man with prior thoracic radiation therapy following resection of a chest wall chondrosarcoma. Coronary angiogram demonstrated significant areas of stenosis in the left main coronary artery (LMCA) and ostial left anterior descending (LAD) coronary artery. The patient was also found to have atretic bilateral internal mammary arteries as a consequence of his radiation therapy, rendering them unsuitable as grafts. Percutaneous coronary intervention (PCI) was thus performed with a successful outcome. To our knowledge, this is the first case of radiation-induced CAD of the LMCA with atretic internal mammary arteries treated successfully with PCI.

Cardio-Oncology: Vascular and Metabolic Perspectives: A Scientific Statement From the American Heart Association

Cardio-oncology has organically developed as a new discipline within cardiovascular medicine as a result of the cardiac and vascular adverse sequelae of the major advances in cancer treatment. Patients with cancer and cancer survivors are at increased risk of vascular disease for a number of reasons. First, many new cancer therapies, including several targeted therapies, are associated with vascular and metabolic complications. Second, cancer itself serves as a risk factor for vascular disease, especially by increasing the risk for thromboembolic events. Finally, recent data suggest that common modifiable and genetic risk factors predispose to both malignancies and cardiovascular disease. Vascular complications in patients with cancer represent a new challenge for the clinician and a new frontier for research and investigation. Indeed, vascular sequelae of novel targeted therapies may provide insights into vascular signaling in humans. Clinically, emerging challenges are best addressed by a multidisciplinary approach in which cardiovascular medicine specialists and vascular biologists work closely with oncologists in the care of patients with cancer and cancer survivors. This novel approach realizes the goal of providing superior care through the creation of cardio-oncology consultative services and the training of a new generation of cardiovascular specialists with a broad understanding of cancer treatments.

Proceedings From the Global Cardio-Oncology Summit: The Top 10 Priorities to Actualize for CardioOncology

The discipline of cardio-oncology has expanded at a remarkable pace. Recent developments and challenges to clinicians who practice cardio-oncology were presented at the Global Cardio-Oncology Summit on October 3 to 4, 2019, in São Paulo, Brazil. Here, we present the top 10 priorities for our field that were discussed at the meeting, and also detail a potential path forward to address these challenges. Defining robust predictors of cardiotoxicity, clarifying the role of cardioprotection, managing and preventing thromboembolism, improving hematopoietic stem cell transplant outcomes, personalizing cardiac interventions, building the cardio-oncology community, detecting and treating cardiovascular events associated with immunotherapy, understanding tyrosine kinase inhibitor cardiotoxicity, and enhancing survivorship care are all priorities for the field. The path forward requires a commitment to research, education, and excellence in clinical care to improve our patients' lives.

Radiation-Associated Cardiac Disease: A Practical Approach to Diagnosis and Management

Radiation-associated cardiac disease (RACD) results in complex clinical presentations, unique management issues, and increased morbidity and mortality. Patients typically present years or even decades after radiation exposure, with delayed-onset cardiac damage sustained from high cumulative doses. Multimodality imaging is crucial to determine the manifestations and severity of disease because symptoms are often nonspecific. Comprehensive screening using a coordinated approach may enable early detection. However, timing of intervention should be carefully considered in these patients because surgery is often complex and high-risk second surgeries should be minimized in the long-term. This review aims to provide treating physicians with a comprehensive and clinically focused overview of RACD, including clinical/imaging manifestations, multi-modality screening recommendations, and management options.

Clinical Outcomes after Transcatheter Aortic Valve Replacement in Cancer Survivors Treated with Ionizing Radiation

BACKGROUND

Improved cancer survival in patients treated with thoracic ionizing radiation (XRT) has resulted in unanticipated surge of aortic stenosis. Transcatheter aortic valve replacement (TAVR) has revolutionized the management of severe aortic stenosis. However, long-term clinical outcomes in radiation-exposed cohorts undergoing TAVR are unknown. We compared the all-cause mortality and major adverse cardiac events (MACE) in patients with prior chest XRT (C-XRT) undergoing TAVR.

METHODS

This is an observational cohort study in subjects who underwent TAVR for symptomatic severe aortic stenosis from 2012 to 2017 in a tertiary care referral center. We examined the all-cause mortality and MACE using cox proportional hazard analysis to identify the clinical predictors of survival in the cohort of patients who had a history of prior C-XRT for malignancy.

RESULTS

Of the 610 patients who underwent TAVR for symptomatic severe aortic stenosis, 75 had prior C-XRT. The majority of C-XRT patients had prior breast cancer (44%) followed by Hodgkin's lymphoma (31%), with the median time from XRT to TAVR of 19.0 years. During a mean follow up of 17.1 months after TAVR, all-cause mortality was 17%. Those with prior C-XRT had higher all-cause mortality (XRT: 29%; non-XRT:15%, p<0.01) and MACE (XRT: 57%; non-XRT: 27%, p<0.001) after TAVR. Patients with prior XRT had a higher incidence of atrial fibrillation (XRT: 48 %; non-XRT: 2.4%, p<0.01) and high-grade heart block (XRT: 20%; non-XRT: 9.1%, p=0.007) requiring pacemaker implant after TAVR. On multivariate cox proportional hazard analysis, prior XRT (HR: 2.07, p=0.003), poor renal function (HR: 1.29, p<0.001) and post-operative anemia requiring transfusion (HR: 1.16, p:0.001) were the strongest predictors of reduced survival.

CONCLUSIONS

Cancer survivors with prior C- XRT have higher incidence of all-cause mortality and MACE after TAVR. Careful patient selection and follow-up strategies are needed to improve outcomes.

Radiation-Associated Cardiac Disease: From Molecular Mechanisms to Clinical Management

PURPOSE OF REVIEW

Radiation-associated cardiac disease (RACD) is an increasingly recognized latent manifestation of chest and mediastinal radiation therapy. The delayed presentation reflects increased survival rates from malignancies successfully treated decades previously. However, individuals are now presenting with multiple coexistent manifestations of RACD and pulmonary disease as a consequence of high-dose radiation administered prior to the routine institution of modern dose-modulating regimens. Increased awareness of RACD is critical for implementation of appropriate screening algorithms and for specific management strategies involving the timing and strategies of intervention in these patients.

RECENT FINDINGS

Recent advances in multimodality cardiac imaging have demonstrated pathognomonic findings of RACD, which can predict outcomes including mortality. Accurate diagnosis of these typically concurrent manifestations is critical and should prompt referral to a center experienced in managing RACD as surgical risk is significantly increased for this patient cohort, particularly for those undergoing redo operation. The latent effect of RACD and its unique combination of manifestations means that these patients will increasingly present with challenging management issues, resulting in increased rates of morbidity and mortality. Timing of treatment intervention must be carefully considered, although percutaneous options may provide alternative future strategies for this higher risk cohort.

Angiographic predictors of adverse outcomes after percutaneous coronary intervention in patients with radiation associated coronary artery disease

OBJECTIVES

To determine procedural predictors of long-term outcomes for patients with radiation associated coronary artery disease (CAD) treated with percutaneous coronary intervention (PCI).

BACKGROUND

Patients who develop CAD after external beam radiation therapy (XRT) for cancer are at high-risk for adverse events following PCI. It is unknown if specific angiographic features can predict outcomes in this population.

METHODS

This is an observational study of 157 patients with malignancy who received XRT prior to PCI. Rates of major adverse cardiovascular and cerebrovascular events (MACCEs; all-cause mortality, myocardial infarction, repeat revascularization, or stroke) were compared across patient characteristics over time with the Cox proportional hazards and Kaplan-Meier's analyses.

RESULTS

During follow-up of 5.4 ± 4.5 years, 91 (58%) patients had MACCE. On Kaplan-Meier's analysis of angiographic characteristics, MACCE was more frequent in patients with at least moderate target vessel calcification (P = 0.023), ostial stenosis (P = 0.049), target vessel diameter ≥ 3.0 mm (P = 0.018), a SYNTAX score ≥ the median of 11 (P = 0.014), or bare metal stenting (BMS)/balloon angioplasty (BA) compared to drug-eluting stenting (DES) (P = 0.006). Cardiac death was more frequent in patients with SYNTAX score ≥ 11 (P = 0.028) or BMS (P = 0.043). After multivariable adjustment for both angiographic and clinical characteristics, independent predictors of MACCE were BMS placement (P = 0.013), chronic kidney disease ≥ stage 3 (P = 0.019), New York Heart Association (NYHA) heart failure class ≥3 (P = 0.034), and SYNTAX score ≥ 11 (P = 0.041).

CONCLUSIONS

In patients previously exposed to XRT treated with PCI, independent angiographic predictors of MACCE include SYNTAX score ≥ 11 and BMS placement, suggestive that DES should be preferred in this population.

Radiation-Induced Coronary Artery Disease and Its Treatment: A Quick Review of Current Evidence

As advances in medical technology arise and the availability of cancer treatment increases, an increased number of patients are receiving cancer treatment. Radiation therapy has evolved to become one of the cornerstones of treatment for various types of cancers. One of the long-term consequences of radiation therapy is radiation-induced coronary artery disease (RICAD). Although the pathophysiology of RICAD may be slightly different and more acute onset than the commonly seen “generic” coronary artery disease, it is common practice to treat RICAD in the same method as nonradiation-induced CAD. This paper summarizes the current research available on the topic and shows there is not enough research to obtain significant data about outcomes and restenosis rates of PCI or outcomes of CABG in RICAD. The aim of this review is to create a concise and easy-to-follow review of the relevant data regarding RICAD and hopefully spark further interest in future studies in this field.

Cardio-oncology: protecting the heart from curative breast cancer treatment

Patients with breast cancer have higher rates of cardiovascular disease than age-matched controls. Anthracyclines and trastuzumab increase the risk of heart failure (HF) and radiation increases the risk of ischemic heart disease, valvular disease and HF. Older age, low normal ejection fraction, history of coronary artery disease (CAD), cardiac risk factors, higher cumulative anthracycline exposure, combination anthracycline and trastuzumab and/or radiation all increase the risk of cardiac events post treatment. Clinical prediction models (CPMs) and/or genetic testing may be useful in guiding treatment decisions but further external validation is necessary. Screening for asymptomatic cardiotoxicity using echocardiography after completion of therapy is reasonable in patients receiving anthracyclines and/or radiation, especially in those with traditional cardiac risk factors such as hypertension, diabetes, hyperlipidemia, and obesity or with low normal baseline left ventricular ejection fraction (LVEF). Elevated cardiac troponins during anthracycline therapy and early reductions in myocardial deformation may predict subsequent reductions in LVEF but further research is needed to demonstrate clinical benefit to routine screening and early treatment. Neurohormonal antagonist therapy with ACEi/ARBs and beta-blockers are indicated in patients with reduced ejection fraction and ongoing research will clarify the role for neurohormonal antagonists and statins for the prevention of breast cancer therapy cardiotoxicity. Patients treated for breast cancer should be educated on the evidence for optimal lifestyle behaviors such as not smoking, regular exercise, healthy diet and maintaining a healthy weight in reducing the risk of cardiovascular disease. Traditional cardiac risk factors such as hypertension, diabetes and hyperlipidemia should be optimally managed to reduce the risk of cardiovascular events in patients treated for breast cancer.

Rate of Progression of Aortic Stenosis and its Impact on Outcomes in Patients With Radiation-Associated Cardiac Disease: A Matched Cohort Study

OBJECTIVES

The aim of this study was to study differences in progression of aortic stenosis (AS) in patients with mediastinal radiotherapy (XRT)-associated moderate AS versus a matched cohort during the same time frame, and to ascertain need for aortic valve replacement (AVR) and longer-term survival.

BACKGROUND

Rate of progression of XRT-associated moderate AS and its impact on outcomes is not well-described.

METHODS

We included 81 patients (age 61 ± 13 years; 57% female) with at least XRT-associated moderate AS (aortic valve area [AVA] 1.05 ± 0.3 cm²; mean gradient 24 ± 10 mm Hg) who had ≥2 transthoracic echocardiograms (TTEs) 1 year apart and matched them in a 1:2 fashion on the basis of age, sex, and AVA with those without prior XRT. Serial aortic valve gradients and AVA were recorded. AVR and longer-term all-cause mortality during follow-up were recorded.

RESULTS

A total of 100% of patients had 1, a total of 71% had 2, and 39% had 3 follow-up TTEs. Before AVR, mean AVG and AVA were not significantly different between XRT and comparison groups. At 3.6 ± 2.0 years from baseline TTE, 146 (60%) underwent AVR (16% transcatheter), with significantly more patients in the XRT group undergoing AVR (80% vs. 50%; p < 0.01), at a much shorter time (2.9 ± 1.6 years vs. 4.1 ± 2.4 years; p < 0.01). At 6.6 ± 4.0 years from the initial TTE, 49 (20%) patients died, with a significantly higher mortality in the XRT group (40% vs. 11%; p < 0.01), with prior XRT associated with increased longer-term mortality, whereas AVR was associated with improved longer-term survival.

CONCLUSIONS

In patients with moderate AS, those with prior XRT have a similar rate of progression of AS versus a comparison group. A higher proportion of patients in the XRT group were referred for AVR at a shorter time from baseline TTE. Despite that, the XRT patients had significantly higher longer-term mortality, and prior exposure to XRT was associated with significantly increased longer-term mortality.

How to prevent and manage radiation-induced coronary artery disease

Radiation-induced coronary heart disease (RICHD) is the second most common cause of morbidity and mortality in patients treated with radiotherapy for breast cancer, Hodgkin's lymphoma and other prevalent mediastinal malignancies. The risk of RICHD increases with radiation dose. Exposed patients may present decades after treatment with manifestations ranging from asymptomatic myocardial perfusion defects to ostial, triple-vessel disease and sudden cardiac death. RICHD is insidious, with a long latency and a tendency to remain silent late into the disease course. Vessel involvement is often diffuse and is preferentially proximal. The pathophysiology is similar to that of accelerated atherosclerosis, characterised by the formation of inflammatory plaque with high collagen and fibrin content. The presence of conventional risk factors potentiates RICHD, and aggressive risk factor management should ideally be initiated prior to radiation therapy. Stress echocardiography is more sensitive and specific than myocardial perfusion imaging in the detection of RICHD, and CT coronary angiography shows promise in risk stratification. Coronary artery bypass grafting is associated with higher risks of graft failure, perioperative complications and all-cause mortality in patients with RICHD. In most cases, the use of drug-eluting stents is preferable to surgical intervention, bare metal stenting or balloon-angioplasty alone.

Long-Term Outcomes of Patients With Mediastinal Radiation-Associated Severe Aortic Stenosis and Subsequent Surgical Aortic Valve Replacement: A Matched Cohort Study

BACKGROUND

Cardiac disease after mediastinal radiotherapy for thoracic malignancy (chest radiotherapy [XRT]) often manifests as progressive aortic stenosis. In patients with XRT-induced severe aortic stenosis undergoing surgical aortic valve replacement (SAVR), we sought to: (1) study long-term survival and compare these patients with a matched cohort undergoing SAVR during the same time frame; and (2) identify potential predictors of long-term mortality.

METHODS AND RESULTS

We studied patients with symptomatic severe aortic stenosis undergoing SAVR at our institution, of which there were 172 mediastinal XRT patients (63±13 years, 62% women) matched in a 1:1 fashion (based on age, sex, time of surgery, and aortic valve area) with 172 non-XRT patients (comparison group). Baseline clinical and postoperative data were obtained. Society of Thoracic Surgeons score was calculated and mortality was recorded. In the XRT group, the median Society of Thoracic Surgeons score was 4% (interquartile range 2-13), while mean left ventricular ejection fraction, left ventricular stroke volume index, and mean aortic valve gradient were 54±11%, 38±14 mL/m2, and 39±11 mm Hg, respectively. In the entire cohort, 27% and 34% of patients underwent concomitant coronary artery bypass grafting and aortic surgery at the time of SAVR, respectively. Thirty-day/in-hospital deaths occurred in 4 (2%) patients in the XRT group and 0 patients in the comparison group. At 6±3 years of follow-up, on matched group analysis, there were 95 (28%) deaths (83 [48%] in the XRT group versus 12 [7%] in the comparison group (log-rank 89, P<0.001). On multivariable Cox survival analysis, in the whole cohort, higher Society of Thoracic Surgeons score (hazard ratio, 1.14; 95% CI, 1.03-1.26) and mediastinal XRT (hazard ratio, 8.12; 95% CI, 4.26-15.64) were associated with increased longer-term mortality (both P<0.01).

CONCLUSIONS

In patients with severe aortic stenosis undergoing SAVR, patients with prior mediastinal XRT have significantly worse longer-term survival versus a matched cohort.

Percutaneous revascularization in patients treated with thoracic radiation for cancer

OBJECTIVES

To assess coronary revascularization outcomes in patients with previous thoracic radiation therapy (XRT).

BACKGROUND

Previous chest radiation has been reported to adversely affect long term survival in patients with coronary disease treated with percutaneous coronary interventions (PCI).

METHODS

Retrospective, single center cohort study of patients previously treated with thoracic radiation and PCI. Patients were propensity matched against control patients without radiation undergoing revascularization during the same time period.

RESULTS

We identified 116 patients with radiation followed by PCI (XRT-PCI group) and 408 controls. Acute procedural complications were similar between groups. There were no differences in all-cause and cardiac mortality between groups (all-cause mortality HR 1.31, P=.078; cardiac mortality 0.78, P=.49).

CONCLUSION

Patients with prior thoracic radiation and coronary disease treated with PCI have similar procedural complications and long term mortality when compared to control subjects.

[Radiation-related heart toxicity: Update in women]

Breast cancer is a common diagnosis in women and thus women are at risk of radiation-induced heart disease, in particular during radiotherapy for left breast cancer and when the internal mammary chain is included. Rates of major cardiac events increase with younger age at the time of irradiation, diagnosis before 1990s, higher radiation doses, coexisting cardiovascular risk factors and adjuvant cardiotoxic chemotherapy. Radiation-induced heart disease comprises a spectrum of cardiac pathologies, including pericardial disease, cardiomyopathy, coronary artery disease and valvular disease. The cardiac injury can appear a long time after radiotherapy and can consist of complex lesions with poor prognosis. The disciplines of cardiology and oncology have increasingly recognized the benefits of collaborating in the care of cancer patients with cardiac disease, developing guidelines for the assessment and management of radiation-related cardiovascular disease. We could consider screening patients with previous chest radiation every 5 years with transthoracic echocardiography and functional imaging. However, prevention remains the primary goal, using cardiac sparing doses and avoidance techniques in radiotherapy to improve patient survival.