Direct oral Xa inhibitors versus warfarin in patients with cancer and atrial fibrillation: a meta-analysis

When anticoagulation management in atrial fibrillation becomes difficult: Focus on chronic kidney disease, coagulation disorders, and cancer

Anticoagulation therapy (AT) is fundamental in atrial fibrillation (AF) treatment but poses challenges in implementation, especially in AF populations with elevated thromboembolic and bleeding risks. Current guidelines emphasize the need to estimate and balance thrombosis and bleeding risks for all potential candidates of antithrombotic therapy. However, administering oral AT raises concerns in specific populations, such as those with chronic kidney disease (CKD), coagulation disorders, and cancer due to lack of robust data. These groups, excluded from large direct oral anticoagulants trials, rely on observational studies, prompting physicians to adopt individualized management strategies based on case-specific evaluations. The scarcity of evidence and specific guidelines underline the need for a tailored approach, emphasizing regular reassessment of risk factors and anticoagulation drug doses. This narrative review aims to summarize evidence and recommendations for challenging AF clinical scenarios, particularly in the long-term management of AT for patients with CKD, coagulation disorders, and cancer.

Antithrombotic strategy in cancer patients comorbid with acute coronary syndrome and atrial fibrillation

It has been shown that patients with cancer have a longer expected life duration, benefiting from advanced medical therapy. Meanwhile, the risk of suffering from cardiovascular disease (CVD) has been increasing with ageing. A growing number of studies have elucidated the association between cancer and CVD. Cancer, atrial fibrillation (AF) and coronary artery disease share some common factors and interact with each other, such as obesity, aging, diabetes, and inflammation, but the potential specific mechanism is still unclear. In addition, cancer-specific and therapy-related factors may increase the risk of embolism and bleeding in patients with cancer than in general population. However, current available embolic and bleeding risk scores applied in patients with CVD may not be applicable for risk assessment in cancer patients, which would be difficult for clinicians to select an appropriate antithrombotic regimen and ensure the balance between bleeding and embolism. Moreover, different types of cancer have distinct risks, which may increase the complexity of antithrombotic therapy. In this review, we review the literature related to cancer, AF, and acute coronary syndrome, focusing on the epidemiological status, physiological mechanism, embolism and bleeding risks, and strategies of antithrombotic therapy.

Effectiveness and Safety of DOACs vs. VKAs in AF Patients With Cancer: Evidence From Randomized Clinical Trials and Observational Studies

Background: The use of direct oral anticoagulants (DOACs) is recommended as the preferred treatment drug in patients with nonvalvular atrial fibrillation (AF). However, the effectiveness and safety of DOACs compared with vitamin K antagonists (VKAs) in patients with cancer and AF are still controversial. Therefore, we performed a meta-analysis regarding the effectiveness and safety of DOACs vs. VKAs in AF patients with cancer. Methods: A search of the Pubmed and EMBASE databases until August 2021 was performed. Adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model with an inverse variance method. Results: Thirteen studies were deemed to meet the criteria. For the effectiveness outcomes, the use of DOACs compared with VKAs use was significantly associated with decreased risks of stroke or systemic embolism (RR = 0.66, 95% CI: 0.54-0.80) and venous thromboembolism (RR = 0.40, 95% CI: 0.26-0.61), but not ischemic stroke (RR = 0.79, 95% CI: 0.56-1.11), myocardial infarction (RR = 0.78, 95% CI: 0.56-1.11), cardiovascular death (RR = 0.76, 95% CI: 0.53-1.09), and all-cause death (RR = 0.82, 95% CI: 0.43-1.56). For the safety outcomes, compared with VKAs use, the use of DOACs was associated with reduced risks of intracranial bleeding (RR = 0.60, 95% CI: 0.50-0.71) and gastrointestinal bleeding (RR = 0.87, 95% CI: 0.80-0.95). There were no significant differences in major bleeding (RR = 0.87, 95% CI: 0.74-1.04), major or nonmajor clinically relevant bleeding (RR = 0.87, 95% CI: 0.74-1.01), and any bleeding (RR = 0.88, 95% CI: 0.76-1.03). Conclusion: Compared with VKAs, DOACs appeared to have significant reductions in stroke or systemic embolism, venous thromboembolism, intracranial bleeding, and gastrointestinal bleeding, but comparable risks of ischemic stroke, myocardial infarction, cardiovascular death, all-cause death, major bleeding, major or nonmajor clinically relevant bleeding, and any bleeding in patients with AF and cancer.

Rate of venous thromboembolism and atrial fibrillation in a real-world case series of advanced cancer patients: the CaTEV Study

BACKGROUND

Venous thromboembolism is the second leading cause of death in cancer patients and its incidence seems underestimated. In addition, cancer patients have an increased risk of developing atrial fibrillation, which may be the first presentation of cancer itself. The primary aim of this study was to define the incidence of venous thromboembolism (VTE) and atrial fibrillation in a real-word series of advanced cancer patients.

METHODS

We performed a retrospective single-institution study on patients diagnosed with stage IV solid neoplasia at the outpatient clinic of the Medical Oncology Unit (Spedali Civili Brescia, Italy), from January to December 2018.

RESULTS

A total of 403 patients were enrolled, with a mean age at presentation of 63 years (range 18-85 years). A VTE was observed in 24% of cases, half of which occurred after diagnosis of metastatic neoplasia, with a median time of onset of 5.5 months (range 0-84). About 3% of patients developed atrial fibrillation after cancer diagnosis. In this patient series, no statistically significant differences were found when comparing Khorana and PROTECHT thromboembolic risk scores, both before and after the start of chemotherapy. Overall, about 25% of the patients received anticoagulant therapy; in most cases, the drug of choice was low-molecular-weight heparin (LMWH).

CONCLUSION

This study showed for cancer patients a considerably higher incidence of VTE and a comparable incidence of atrial fibrillation than reported in literature. Validated thromboembolic risk scores appear to be poorly predictive, and LMWH remains the most widely used anticoagulant drug.

Anticoagulation in patients with atrial fibrillation and active cancer: an international survey on patient management

BACKGROUND

In patients with active cancer and atrial fibrillation (AF) anticoagulation, thrombotic and bleeding risk still entail uncertainty.

AIM

We explored the results of an international survey examining the knowledge and behaviours of a large group of physicians.

METHODS AND RESULTS

A web-based survey was completed by 960 physicians (82.4% cardiologists, 75.5% from Europe). Among the currently available anticoagulants for stroke prevention in patients with active cancer, direct oral anticoagulants (DOACs) were preferred by 62.6%, with lower values for low molecular weight heparin (LMWH) (24.1%) and for warfarin (only 7.3%). About 46% of respondents considered that DOACs should be used in all types of cancers except in non-operable gastrointestinal cancers. The lack of controlled studies on bleeding risk (33.5% of respondents) and the risk of drug interactions (31.5%) were perceived as problematic issues associated with use of anticoagulants in cancer. The decision on anticoagulation involved a cardiologist in 27.8% of cases, a cardiologist and an oncologist in 41.1%, and a team approach in 21.6%. The patient also was involved in decision-making, according to ∼60% of the respondents. For risk stratification, use of CHA2DS2-VASc and HAS-BLED scores was considered appropriate, although not specifically validated in cancer patients, by 66.7% and 56.4%, respectively.

CONCLUSION

This survey highlights that management of anticoagulation in patients with AF and active cancer is challenging, with substantial heterogeneity in therapeutic choices. Direct oral anticoagulants seems having an emerging role but still the use of LMWH remains substantial, despite the absence of long-term data on thromboprophylaxis in AF.