Atrial Fibrillation and Stroke Risk in Patients With Cancer: A Primer for Oncologists

Cancer patients and ischemic stroke

Patients with cancer have an increased risk of ischemic stroke compared to the general population. Additionally, these patients have a worse prognosis compared to stroke patients without cancer. Activation of coagulation appears to play a key role in the pathophysiology of ischemic stroke in patients with cancer. However, the underlying mechanisms remain unknown. Moreover, we do not have a way to identify cancer patients with a high risk of stroke and cannot develop prevention strategies. Therefore, there is an urgent need for neurologists and oncologists to develop screening and prevention strategies for stroke in patients with cancer. In this review, we summarize the characteristics of cancer patients at a high risk of stroke, the predictors for the development of stroke and survival in cancer patients, and possible treatments.

Oral anticoagulant prescribing among patients with cancer and atrial fibrillation in England, 2009-2019

BACKGROUND

Anticoagulation of patients with atrial fibrillation (AF) and cancer is challenging because of their high risk for stroke and bleeding. Little is known of the variations of oral anticoagulant (OAC) prescribing in patients with AF with and without cancer.

METHODS

Patients with first-time AF during 2009-2019 from the Clinical Practice Research Datalink were included. Cancer diagnosis was defined as a history of breast, prostate, colorectal, lung, or hematological cancer. Competing-risk analysis was used to assess the risk of OAC prescribing in patients with AF and cancer adjusted for clinical and sociodemographic factors.

RESULTS

Of 177,065 patients with AF, 11.7% had cancer. Compared to patients without cancer, patients with cancer were less likely to receive OAC: prostate cancer (subhazard ratio [SHR], 0.95; 95% CI, 0.91-0.99), breast cancer (SHR, 0.93; 95% CI, 0.89-0.98), colorectal cancer (SHR, 0.93; 95% CI, 0.88-0.99), hematological cancer (SHR, 0.70; 95% CI, 0.65-0.75), and lung cancer (SHR, 0.44; 95% CI, 0.38-0.50). The cumulative incidence function (CIF) of OAC prescribing was lowest for patients with lung cancer and hematological cancer compared with patients without cancer. The difference between the CIF of OAC prescribing in patients with and without cancer becomes narrower in the most deprived areas. Elderly patients (aged ≥85 years) overall had the lowest CIF of OAC prescribing regardless of cancer status.

CONCLUSIONS

In patients with AF, underprescribing of OAC is independently associated with certain cancer types. Patients with hematological and lung cancer are the least likely to receive anticoagulation therapy compared with patients without cancer. Underprescribing of OAC in cancer is linked to old age. Further studies of patients with AF and cancer are warranted to assess the net clinical benefit of anticoagulation in certain cancer types.

Development and Validation of Machine Learning Algorithms to Predict 1-Year Ischemic Stroke and Bleeding Events in Patients with Atrial Fibrillation and Cancer

In this study, we leveraged machine learning (ML) approach to develop and validate new assessment tools for predicting stroke and bleeding among patients with atrial fibrillation (AFib) and cancer. We conducted a retrospective cohort study including patients who were newly diagnosed with AFib with a record of cancer from the 2012-2018 Surveillance, Epidemiology, and End Results (SEER)-Medicare database. The ML algorithms were developed and validated separately for each outcome by fitting elastic net, random forest (RF), extreme gradient boosting (XGBoost), support vector machine (SVM), and neural network models with tenfold cross-validation (train:test = 7:3). We obtained area under the curve (AUC), sensitivity, specificity, and F2 score as performance metrics. Model calibration was assessed using Brier score. In sensitivity analysis, we resampled data using Synthetic Minority Oversampling Technique (SMOTE). Among 18,388 patients with AFib and cancer, 523 (2.84%) had ischemic stroke and 221 (1.20%) had major bleeding within one year after AFib diagnosis. In prediction of ischemic stroke, RF significantly outperformed other ML models [AUC (0.916, 95% CI 0.887-0.945), sensitivity 0.868, specificity 0.801, F2 score 0.375, Brier score = 0.035]. However, the performance of ML algorithms in prediction of major bleeding was low with highest AUC achieved by RF (0.623, 95% CI 0.554-0.692). RF models performed better than CHA2DS2-VASc and HAS-BLED scores. SMOTE did not improve the performance of the ML algorithms. Our study demonstrated a promising application of ML in stroke prediction among patients with AFib and cancer. This tool may be leveraged in assisting clinicians to identify patients at high risk of stroke and optimize treatment decisions.

Benefit and risk of oral anticoagulant initiation strategies in patients with atrial fibrillation and cancer: a target trial emulation using the SEER-Medicare database

Oral anticoagulants (OACs) are recommended for patients with atrial fibrillation (AFib) having CHA2DS2-VASc score ≥ 2. However, the benefits of OAC initiation in patients with AFib and cancer at different levels of CHA2DS2-VASc is unknown. We included patients with new AFib diagnosis and a record of cancer (breast, prostate, or lung) from the 2012-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare database (n = 39,915). Risks of stroke and bleeding were compared between 5 treatment strategies: (1) initiated OAC when CHA2DS2-VASc ≥ 1 (n = 6008), (2) CHA2DS2-VASc ≥ 2 (n = 8694), (3) CHA2DS2-VASc ≥ 4 (n = 20,286), (4) CHA2DS2-VASc ≥ 6 (n = 30,944), and (5) never initiated OAC (reference group, n = 33,907). Confounders were adjusted using inverse probability weighting through cloning-censoring-weighting approach. Weighted pooled logistic regressions were used to estimate treatment effect [hazard ratios (HRs) and 95% confidence interval (95% CIs)]. We found that only patients who initiated OACs at CHA2DS2-VASc ≥ 6 had lower risk of stroke compared without OAC initiation (HR 0.64, 95% CI 0.54-0.75). All 4 active treatment strategies had reduced risk of bleeding compared to non-initiators, with OAC initiation at CHA2DS2-VASc ≥ 6 being the most beneficial strategy (HR = 0.49, 95% CI 0.44-0.55). In patients with lung cancer or regional/metastatic cancer, OAC initiation at any CHA2DS2-VASc level increased risk of stroke and did not reduce risk of bleeding (except for Regimen 4). In conclusion, among cancer patients with new AFib diagnosis, OAC initiation at higher risk of stroke (CHA2DS2-VASc score ≥ 6) is more beneficial in preventing ischemic stroke and bleeding. Patients with advanced cancer or low life-expectancy may initiate OACs when CHA2DS2-VASc score ≥ 6.

Malignancy-associated ischemic stroke: Implications for diagnostic and therapeutic workup

BACKGROUND

Patients with malignancies have an increased risk of suffering ischemic stroke via several mechanisms such as coagulation dysfunction and other malignancy-related effects as well as iatrogenic causes. Moreover, stroke can be the first sign of an occult malignancy, termed as malignancy-associated ischemic stroke (MAS). Therefore, timely diagnostic assessment and targeted management of this complex clinical situation are critical.

FINDINGS

Patients with both stroke and malignancy have atypical ages, risk factors, and often exhibit malignancy-related symptoms and multiple lesions on neuroimaging. New biomarkers such as eicosapentaenoic acid and blood mRNA profiles may help in distinguishing MAS from other strokes. In terms of treatment, malignancy should not be considered a contraindication, given comparable rates of recanalization and complications between stroke patients with or without malignancies.

CONCLUSION

In this review, we summarize the latest developments in diagnosing and managing MAS, especially stroke with occult malignancies, and provide new recommendations from recently emerged clinical evidence for diagnostic and therapeutic workup strategies.

Risk of arterial thromboembolism, bleeding and mortality in atrial fibrillation patients with comorbid cancer: A systematic review and meta-analysis

AIMS

Atrial fibrillation (AF) and cancer often co-exist. Each has been associated with an increased risk of morbidity and mortality. The aim of this meta-analysis was to synthesize available data regarding the incidence of arterial thromboembolism (TE), bleeding, and all-cause mortality in patients with AF with or without cancer.

METHODS

Literature search was conducted in PubMed, Ovid MEDLINE, WebOfScience, Scopus, CENTRAL, OpenGrey, and EThOS databases to identify studies that included patients with AF and accounted for cancer status with the incidence of TE (ischemic stroke, transient ischemic attack, or arterial thrombosis), major or clinically relevant non-major bleeding, and all-cause mortality. A random-effects meta-analysis was used.

RESULTS

Overall, 17 studies were included (3,149,547 patients). The risk of TE was similar in patients with AF with comorbid cancer compared with that in AF alone (pooled odds ratio [pOR] 0.97, 95% Confidence Interval [CI] 0.85-1.11, I2 = 87%). Major or clinically relevant non-major bleeding (pOR 1.65, 95% CI 1.35-2.02, I2 = 98%) and all-cause death (pOR 2.17, 95% CI 1.83-2.56, I2 = 98%) were significantly higher in patients with AF with cancer than in patients with AF only. The history of TE and hypertension and mean age were significant moderators of TE risk.

CONCLUSION

In patients with AF, the presence of cancer is associated with a similar risk of TE as well as an increased risk of bleeding and all-cause death compared with the absence of cancer.

Treatment of acute ischemic stroke in patients with active malignancy: insight from a comprehensive stroke center

Background

Despite the high incidence of acute ischemic stroke (AIS) in cancer patients, there is still no consensus about the safety of recanalization therapies in this cohort.

Objectives

In this observational study, our aim was to investigate the bleeding risk after acute recanalization therapy in AIS patients with active malignancy.

Methods and Study Design

We retrospectively analyzed observational data of 1016 AIS patients who received intravenous thrombolysis with rtPA (IVT) and/or endovascular therapy (EVT) between January 2017 and December 2020 with a focus on patients with active malignancy. The primary safety endpoint was the occurrence of stroke treatment-related major bleeding events, that is, symptomatic intracranial hemorrhage (SICH) and/or relevant systemic bleeding. The primary efficacy endpoint was neurological improvement during hospital stay (NI).

Results

None of the 79 AIS patients with active malignancy suffered from stroke treatment-related systemic bleeding. The increased rate (7.6% versus 4.7%) of SICH after therapy compared to the control group was explained by confounding factors. A total of nine patients with cerebral tumor manifestation received acute stroke therapy, two of them suffered from stroke treatment-related intracranial hemorrhage remote from the tumor, both asymptomatic. The group of patients with active malignancy and the control group showed comparable rates of NI.

Conclusion

Recanalization therapy in AIS patients with active malignancy was not associated with a higher risk for stroke treatment-related systemic or intracranial bleeding. IVT and/or EVT can be regarded as a safe therapy option for AIS patients with active malignancy.

Outcomes and Discriminatory Accuracy of the CHA2DS2VASc Score in Atrial Fibrillation and Cancer

Background

Atrial fibrillation (AF) is highly prevalent among cancer patients. The role of traditional risk stratification scores in the context of different cancer types in these patients remains unknown.

Objectives

The purpose of this study was to determine the discriminative accuracy of the CHA2DS2VASc score for ischemic stroke using receiver operating characteristic and area under the curve.

Methods

The National Readmission Database (2015-2019) was used to identify all AF patients stratified by the cancer diagnosis, type, and CHA2DS2VASc category (low; moderate; high risk). Outcomes at 30-day readmission were compared between cancer and noncancer groups using hierarchical multivariable logistic regression to calculate adjusted odds ratios (aORs) and 95% CIs.

Results

A total of 6,996,088 AF patients were identified at index admission. Of these, 4,242,630 (642,237 cancer, 3,600,393 noncancer) were readmitted at 30 days. Cancer patients (92.1%) had a higher proportion of high CHA2DS2VASc scores compared with their noncancer counterparts (89.8%, P < 0.001). The 30-day readmission rate and incidence of major bleeding in cancer patients were significantly higher compared with their corresponding noncancer group across all CHA2DS2VASc categories. Among the different cancer types, hematological and lung cancer had a high propensity for major bleeding. The odds of ischemic stroke were lower in the cancer group across high (1.9% vs 2.4%; aOR: 0.78; 95% CI: 0.76-0.79; P < 0.0001), moderate (0.8% vs 1.3%; aOR: 0.57; 95% CI: 0.50-0.64; P < 0.0001), and low (0.4% vs 0.9%; aOR: 0.46; 95% CI: 0.34-0.62; P < 0.0001) risk category relative to the noncancer group irrespective of type of cancer. CHA2DS2VASc category had a statistically significant discriminatory accuracy for ischemic stroke in both cancer and noncancer patients.

Conclusions

Cancer patients with AF are at a higher risk of readmission and major bleeding. The risk of ischemic stroke during readmission appears to be lower than noncancer patients. These findings may have implications for anticoagulant therapy in cancer patients.

Left Atrial Appendage Closure Outcomes in Patients With Cancer at a Single Tertiary Center

Atrial fibrillation is the most common arrhythmia in patients with underlying malignancy. Patients with cancer have a higher risk of bleeding, and at the same time, carry an elevated risk of thromboembolism related to the hypercoagulable state, type of cancer, and anticancer treatment, rendering safe anticoagulation challenging in this population. Left atrial appendage closure is an alternative treatment option in patients with atrial fibrillation and high bleeding risk; however, the data on patients with cancer are limited. Our study aimed to compare the long-term outcomes in patients with cancer receiving left atrial appendage closure using the WATCHMAN device. This is a prospective, single-center study comparing outcomes in 389 patients who underwent percutaneous left atrial appendage closure using the WATCHMAN device over 5 years in a single, large academic hospital in the United States. The postprocedural outcomes of mortality, stroke, and major bleeding were evaluated in patients with and without cancer. Our study included 57 patients with cancer and 332 without cancer. The baseline characteristics were similar between the 2 groups. Metastatic disease was present in 16.4% of patients, and 25% were receiving active treatment at the time of the procedure. The median follow-up time was 354 (interquartile range 85 to 790) days. There was no difference in mortality (hazard ratio [HR] 1.3, 95% confidence interval [CI] 0.72 to 2.35, p = 0.38), major bleeding episodes (HR 1.2, 95% CI 0.45 to 3.33, p = 0.68), and stroke (HR 0.64, 95% CI 0.19 to 2.21, p = 0.49) at 3 years after the procedure in patients with and without cancer. There was no difference in the composite outcome (postprocedural mortality, stroke, and major bleeding) between the 2 groups (HR 1.25, CI 0.75 to 2.07, p = 0.38). Percutaneous left atrial appendage closure in patients with cancer appears to be safe and has a similar long-term risk compared with patients without cancer.

Stroke and cancer

Association between stroke and cancer is well-established and has led to a growing literature over the past decades. Risk of ischemic and hemorrhagic stroke is increased among patients with newly diagnosed cancer and 5-10% of stroke patients bear an active cancer. All cancers are concerned, but hematological malignancy in childhood and adenocarcinoma from lung, digestive tract and pancreas in adults are most usually identified. Unique stroke mechanisms are dominated by hypercoagulation, a condition that may lead to both arterial and venous cerebral thromboembolism. Direct tumor effects, infections and therapies may also play some active role in stroke happening. Magnetic Resonance Imaging (MRI) is helpful in: i) detecting typical patterns of ischemic stroke in cancer patients (i.e. concomitant strokes in multiple arterial territories); ii) distinguishing spontaneous intracerebral hemorrhage from tumor bleeding. Recent literature suggests that acute treatment using intravenous thrombolysis is safe in non-metastatic cancer patients. First results from endovascular procedures are reassuring, although arterial reobstruction is more frequent than in cancer-free patients. Prognosis is worse in patients with compared to those without cancer and mostly depends upon several predictors such as the initial stroke severity and the presence of metastasis. In the present review, we aim to provide some practical responses to neurologists about the stroke-cancer association, including prevalence, stroke mechanisms, biomarkers indicative for an occult cancer, influence of neoplasia on acute and long-term stroke treatments, and prognosis.

Kinase Inhibitors and Atrial Fibrillation

Recent advances have significantly expanded the options of available therapeutics for cancer treatment, including novel targeted cancer therapies. Within this broad category of targeted therapies is the class of kinase inhibitors (KIs), which target kinases that have undergone aberrant activation in cancerous cells. Although KIs have shown a benefit in treating various forms of malignancy, they have also been shown to cause a wide array of cardiovascular toxicities, with cardiac arrhythmias, in particular atrial fibrillation (AF), being 1 of the predominant side effects. The occurrence of AF in patients undergoing cancer treatment can complicate the treatment approach and poses unique clinical challenges. The association of KIs and AF has led to new research aimed at trying to elucidate the underlying mechanisms. Furthermore, there are unique considerations to treating KI-induced AF because of the anticoagulant properties of some KIs as well as drug-drug interactions with KIs and some cardiovascular medications. Here, we review the current literature pertaining to KI-induced AF.

Atrial fibrillation and cancer: prevalence and relative risk from a nationwide study

Background

Atrial fibrillation (AF) is an increasingly recognized codiagnosis in patients with cancer.

Objectives

This study aimed to provide a robust and contemporary estimate on the coprevalence and relative risk of AF in patients with cancer.

Methods

We conducted a nationwide analysis, utilizing diagnosis codes from the Austrian Association of Social Security Providers dataset. Estimates of the coprevalence of cancer and AF and the relative risk of AF in patients with cancer compared with individuals without cancer were obtained as point prevalences with binomial exact confidence intervals and summarized across age groups and cancer types with random-effects models.

Results

Overall, 8,306,244 persons were included in the present analysis, of whom 158,675 (prevalence estimate, 1.91%; 95% CI, 1.90-1.92) had a cancer diagnosis code and 112,827 (1.36%; 95% CI, 1.35-1.36) an AF diagnosis code, respectively. The prevalence estimate for AF in patients with cancer was 9.77% (95% CI, 9.63-9.92) and 1.19% (95% CI, 1.19-1.20) in the noncancer population. Conversely, 13.74% (95% CI, 13.54-13.94) of patients with AF had a concurrent cancer diagnosis. The corresponding age-stratified random-effects relative risk ratio for AF in patients with cancer compared with no cancer diagnosis was 10.45 (95% CI, 7.47-14.62). The strongest associations between cancer and AF were observed in younger persons and patients with hematologic malignancies.

Conclusion

Cancer and AF have a substantial coprevalence in the population. This finding corroborates the concept that cancer and AF have common risk factors and pathophysiology.

Comparative Effectiveness and Safety of Direct Oral Anticoagulants Versus Warfarin Among Adults With Cancer and Atrial Fibrillation

BACKGROUND

While clinical guidelines recommend direct-acting oral anticoagulants (DOAC) over warfarin to treat isolated nonvalvular atrial fibrillation, guidelines are silent regarding nonvalvular atrial fibrillation treatment among individuals with cancer, reflecting the paucity of evidence in this setting. We quantified relative risk of ischemic stroke or systemic embolism and major bleeding (primary outcomes), and all-cause and cardiovascular death (secondary outcomes) among older individuals with cancer and nonvalvular atrial fibrillation comparing DOACs and warfarin.

METHODS

This retrospective cohort study used Surveillance, Epidemiology, and End Results cancer registry and linked US Medicare data from 2010 through 2016, and included individuals diagnosed with cancer and nonvalvular atrial fibrillation who newly initiated DOAC or warfarin. We used inverse probability of treatment weighting to control confounding. We used competing risk regression for primary outcomes and cardiovascular death, and Cox proportional hazard regression for all-cause death.

RESULTS

Among 7675 individuals included in the cohort, 4244 (55.3%) received DOACs and 3431 (44.7%) warfarin. In the inverse probability of treatment weighting analysis, there was no statistically significant difference among DOAC and warfarin users in the risk of ischemic stroke or systemic embolism (1.24 versus 1.19 events per 100 person-years, adjusted hazard ratio 1.41 [95% CI, 0.92-2.14]), major bleeding (3.08 versus 4.49 events per 100 person-years, adjusted hazard ratio 0.90 [95% CI, 0.70-1.17]), and cardiovascular death (1.88 versus 3.14 per 100 person-years, adjusted hazard ratio 0.82 [95% CI, 0.59-0.1.13]). DOAC users had significantly lower risk of all-cause death (7.09 versus 13.3 per 100 person-years, adjusted hazard ratio 0.81 [95% CI, 0.69-0.94]) compared to warfarin users.

CONCLUSIONS

Older adults with cancer and atrial fibrillation exposed to DOACs had similar risks of stroke and systemic embolism and major bleeding as those exposed to warfarin. Relative to warfarin, DOAC use was associated with a similar risk of cardiovascular death and a lower risk of all-cause death.

Treatment Options in AF Patients with Cancer; Focus on Catheter Ablation

Longer life expectancy along with advancements in cancer and atrial fibrillation (AF) therapies and treatment strategies have led to an increase in the number of individuals with both diseases. As a result, the complicated management of these patients has become crucial, necessitating individualised treatment that considers the bi-directional relationship between these two diseases. On the one hand, giving appropriate pharmaceutical therapy is exceptionally difficult, considering the recognised thromboembolic risk posed by AF and malignancy, as well as the haemorrhagic risk posed by cancer. The alternative pulmonary vein isolation (PVI) ablation, on the other hand, has been inadequately explored in the cancer patient population; there is yet inadequate data to allow the clinician to unambiguously select patients that can undertake this therapeutic intervention. The goal of this review is to compile the most valuable data and supporting evidence about the characteristics, care, and therapy of cancer patients with AF. Specifically, we will evaluate the pharmaceutical options for a proper anticoagulant therapy, as well as the feasibility and safety of PVI in this population.

Practical recommendations to combine small-molecule inhibitors and direct oral anticoagulants in patients with nonsmall cell lung cancer

BACKGROUND

The risk for thromboembolisms in nonsmall cell lung cancer (NSCLC) patients is increased and often requires treatment or prophylaxis with direct oral anticoagulants (DOACs). Small-molecule inhibitors (SMIs) to treat NSCLC may cause relevant drug-drug interactions (DDIs) with DOACs. Guidance on how to combine these drugs is lacking, leaving patients at risk of clotting or bleeding. Here, we give practical recommendations to manage these DDIs.

METHODS

For all DOACs and SMIs approved in Europe and the USA up to December 2021, a literature review was executed and reviews by the US Food and Drug Administration and European Medicines Agency were analysed for information on DDIs. A DDI potency classification for DOACs was composed and brought together with DDI characteristics of each SMI, resulting in recommendations for each combination.

RESULTS

Half of the combinations result in relevant DDIs, requiring an intervention to prevent ineffective or toxic treatment with DOACs. These actions include dose adjustments, separation of administration or switching between anticoagulant therapies. Combinations of SMIs with edoxaban never cause relevant DDIs, compared to more than half of combinations with other DOACs and even increasing to almost all combinations with rivaroxaban.

CONCLUSIONS

Combinations of SMIs and DOACs often result in relevant DDIs that can be prevented by adjusting the DOAC dosage, separation of administration or switching between anticoagulants.

Use of oral anticoagulants among individuals with cancer and atrial fibrillation in the United States, 2010-2016

Background

Anticoagulation among patients with cancer and atrial fibrillation is challenging due to elevated risk of bleeding and stroke. We characterized use of oral anticoagulants among patients with cancer and non‐valvular atrial fibrillation (NVAF).

Methods

We used Surveillance, Epidemiology, and End Results (SEER)‐Medicare data and included patients with cancer aged ≥66 years with an incident diagnosis of NVAF from 2010 to 2016. We used a Cox proportional hazard model and multivariable logistic regression to identify factors associated with anticoagulant use versus no use and direct oral anticoagulants (DOACs) versus warfarin use, respectively.

Results

Of 27,702 patients with cancer and NVAF, 4469 (16.1%) used DOACs and 3577 (12.9%) used warfarin. Among 8046 anticoagulant users, DOACs use increased from 21.8% in 2011 to 76.2% in 2016, with a corresponding decline in warfarin use from 78.2% to 23.8%. Nearly 7 out of 10 patients with cancer and NVAF did not initiate anticoagulation in 2016. Anticoagulant use was more likely among those with higher CHA₂DS₂‐VASc scores (hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.27–1.90 for score ≥6 vs. 1) or with lower HAS‐BLED scores (HR 1.96, 95% CI 1.67–2.30 for score 1 vs. ≥6). Among anticoagulant users, DOAC use was less likely than warfarin in those with higher CHA₂DS₂‐VASc scores (odds ratio [OR] 0.53, 95% CI 0.33–0.84 for score ≥6 vs. 1).

Conclusions

Nearly 7 out of 10 patients with cancer and NVAF did not receive anticoagulation. Use of DOACs increased from 2010 to 2016, with a corresponding decline in warfarin use. DOACs are used less than warfarin among those at higher risk of stroke.

Atrial fibrillation in older adults with cancer

Cancer and atrial fibrillation (AF) are common co-morbid conditions in older adults. Both cancer and cancer treatment increase the risk of developing new AF which increases morbidity and mortality. Heart rate and rhythm control along with anticoagulation therapy remain the mainstay of treatment of AF in older adults with both cancer and AF. Adjustments to the treatment may be necessary because of drug interactions with concurrent chemotherapy. Cancer and old age increase the risk of both, thromboembolism and bleeding. The risk of these complications is further enhanced by concomitant cancer therapy, frailty, poor nutrition status and, coexisting geriatric syndromes. Therefore, careful attention needs to be given to the risks and benefits of using anticoagulant medications. This review focuses on the management of AF in older patients with cancer, including at the end-of-life care.

Atrial Fibrillation in Cancer Patients: Who is at Risk?

Cancer is the second leading cause of mortality in the world, second only to cardiovascular diseases. Simultaneously cancer mortality has been steadily decreasing due to the development  of new chemotherapy and targeted  drugs  and the improvement  of existing  treatment protocols.  Improving the prognosis of treatment of cancer patients leads to an unexpected  result - more patients are faced with side effects of cancer treatment. Cardiotoxicity, including  arrhythmia, has  become  a significant  factor  to reduce  the effectiveness  of cancer  patient’s  treatment.  Atrial  fibrillation  is frequent  and persistent a rhythm disorder, affecting  all categories  of patients, especially the elderly. An association  between these two conditions  can be expected, considering the fact that in old age the prevalence of malignant neoplasms  and comorbid pathology predisposing to the onset of AF is high. Therefore, AF may be an additional  factor negatively  influencing the prognosis and treatment tactics in patients with malignant neoplasms. A comprehensive search was conducted  using the keywords  “cancer”, “atrial fibrillation” and “cardiotoxicity” using the PubMed,  Scopus and Cohrane  databases. We reviewed publications having the relationship between AF and cancer. The literature review considered 61 publications on the prevalence of AF in cancer patients, classification, mechanisms of development, the effect of anticancer drugs and other treatment methods on this group of patients. Analyzed articles include clinical guidelines, consensus  expert opinions,  systematic  reviews,  meta-analyzes, and previously  published  reviews of the literature. The problem of cardiotoxic  complications diagnostics is evaluated separately,  incl. arrhythmias, and their monitoring in cancer patients. Therefore, the direction of medicine named "Cardio-oncology" comes to the fore. Interdisciplinary interaction will allow identify cardiotoxic  manifestations at the subclinical stage and optimize anticancer treatment.