Prophylactic Rivaroxaban Therapy for Left Ventricular Thrombus After Anterior ST-Segment Elevation Myocardial Infarction

Left Ventricular Thrombus Management After Acute Myocardial Infarction in Clinical Practice: Results from LEVITATION Survey and Narrative Review

PURPOSE

Left ventricular thrombus (LVT) after ST-elevation myocardial infarction still presents diagnostic and therapeutic challenges. The LEVITATION survey was designed to take a picture of LVT management in current clinical practice.

METHODS

The survey covered diagnostic, therapeutic, and prophylactic issues and was completed by 104 European cardiac centers. Most of them (59%) were university or tertiary centers.

RESULTS

The survey showed anterior apical a-/dyskinesia, large MI, spontaneous echo-contrast, late presentation with delayed PCI, and TIMI flow 0-1 as the most important perceived risk factors for LVT formation. Serial ultrasound imaging is the most used tool to diagnose LVT (88% of the centers), with contrast-enhanced ultrasound and cardiac MR performed in case of poor apex visualization or spontaneous echo-contrast. One third (34%) of the centers uses prophylactic anticoagulation to prevent LVT formation. In the presence of LVT, low molecular weight heparin is the most used in-hospital therapy. At discharge, vitamin K antagonist and direct oral anticoagulants are used in 67 and 32% of the cases, respectively. Triple antithrombotic therapy with aspirin plus clopidogrel and VKA is the most used strategy at discharge (55%), whereas a single antiplatelet therapy is preferred only in the case of moderate-to-high risk of bleeding. To assess LVT total regression, half of the centers use contrast-enhanced ultrasound and/or cardiac-MR. The duration of anticoagulation is usually 3-6 months (55%), with long-term prolongation in case of LVT persistence or recurrence.

CONCLUSION

The survey has depicted for the first time the current real-world management of this neglected topic and has highlighted several grey zones that are still present and not supported by evidence.

Emerging Trends in Left Ventricular Thrombus: A Comprehensive Review of Non-Ischemic and Ischemic Cardiopathies, Including Eosinophilic Myocarditis, Chagas Cardiomyopathy, Amyloidosis, and Innovative Anticoagulant Approaches

This comprehensive review explores the intricate aspects of left ventricular thrombus (LVT), a potential complication in both ischemic and non-ischemic cardiomyopathies. It provides a thorough understanding of left ventricular thrombus, revealing its uncommon incidence in the general population (7 cases per 10,000 patients), predominantly linked to ischemic heart diseases (ICMs) at an 80% prevalence rate. Diagnostic tools, notably transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR), demonstrate varying sensitivity but remain indispensable in specific clinical contexts related to LVT as non-invasive diagnostic modalities. A detailed comparison between ICM patients and those with non-ischemic cardiomyopathy (NICM) who have left ventricular thrombus reveals subtle distinctions with significant clinical implications. This analysis underscores the importance of these imaging techniques in distinguishing between the two conditions. Additionally, we explored the occurrence of LVT in specific non-ischemic cardiomyopathies, including Takotsubo syndrome, hypertrophic cardiomyopathy, eosinophilic myocarditis, Chagas disease, cardiac amyloidosis, and several other conditions. The article further delves into anticoagulation strategies, thoroughly examining their impact on LVT regression and patient outcomes. Pharmacological interventions, with a focus on direct oral anticoagulants, emerge as promising alternatives; however, there is insufficient information on their efficiency and safety, especially in NICM population. In conclusion, this review highlights the complex nature of LVT, incorporating a range of etiopathogenic factors, diagnostic complexities, and evolving therapeutic approaches. It emphasizes the pressing need for ongoing research in this field.

Epidemiology and current management of cardiovascular disease in China

The Annual Report on Cardiovascular Health and Diseases in China (2022) intricate landscape of cardiovascular health in China. This is the fourth section of the report with a specific focus on epidemiology and current management of cardiovascular disease (CVD) in China. This section of the report highlights the epidemiological trends of CVD in China. It reveal a concerning rise in prevalence, with approximately 330 million affected individuals, including significant numbers with stroke, coronary artery disease (CAD), heart failure, and other conditions. CVD stands as the primary cause of mortality among both urban and rural populations, accounting for nearly half of all deaths in 2020. Mortality rates are notably higher in rural areas compared to urban centers since 2009. While age-standardized mortality rates have decreased, the absolute number of CVD deaths has increased, primarily due to population aging. Ischemic heart disease, hemorrhagic and ischemic strokes are the leading causes of CVD-related deaths. Notably, the burden of atherosclerotic cardiovascular disease has risen substantially, with atherosclerotic cardiovascular disease-related deaths increasing from 1990 to 2016. The incidence of ischemic stroke and ischemic heart disease has shown similar increasing trends over the past three decades. CAD mortality, particularly acute myocardial infarction, has been on the rise, with higher mortality rates observed in rural areas since 2016. The prevalence of CAD has increased significantly, with over 11 million patients identified in 2013. Studies assessing hospital performance in managing acute coronary syndrome reveal gaps in adherence to guideline-recommended strategies, with disparities in care quality across hospitals. However, initiatives like the China Patient-centered Evaluative Assessment of Cardiac Events (PEACE)-Retrospective AMI Study and the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome (CCC-ACS) project aim to improve patient outcomes through enhanced care protocols. Moreover, advancements in medical technology, such as quantitative flow ratio-guided lesion selection during percutaneous coronary intervention, show promise in improving clinical outcomes for patients undergoing intervention.

Prophylactic Anticoagulation to Prevent Left Ventricular Thrombus Following Acute Myocardial Infarction: A Systematic Review and Meta-Analysis

Clinical practice guidelines from the American Heart Association recommend consideration of prophylactic anticoagulation to prevent left ventricular thrombus (LVT) formation in patients with anterior ST-elevation myocardial infarction. These guidelines were given a low certainty of evidence (class IIb, level C), relying primarily on case studies and expert consensus to inform practice. Our objective was to compare the safety and efficacy of prophylactic anticoagulation, in addition to dual antiplatelet therapy, in the current era of timely primary percutaneous coronary intervention. Electronic databases, including EMBASE, MEDLINE, and Cochrane Library, were systematically searched from January 2012 through June 2022. A total of 7,378 publications were screened, and 5 publications were eventually included in this review: 1 randomized control trial and 4 retrospective studies involving 1,461 patients. Data were pooled using a fixed-effects model and reported as odds ratios (ORs) with 95% confidence intervals (CIs). The primary outcome of interest was the rate of LVT formation, and the secondary outcomes were the rate of major bleeding and systemic embolism. Pooled analysis showed a significantly lower rate of LVT formation (OR 0.28, 95% CI 0.11 to 0.73, p <0.01) and significantly higher rates of bleeding (OR 2.85, 95% CI 1.13 to 7.24, p = 0.03) in the triple therapy group compared with dual antiplatelet therapy. No significant difference was observed in the rate of systemic embolism between the groups (OR 0.37, 95% CI 0.12 to 1.13, p = 0.08). In this meta-analysis, there is no conclusive evidence to either support or oppose the use of triple therapy for LVT prevention in patients with anterior ST-elevation myocardial infarction treated with primary percutaneous coronary intervention. Appropriately powered randomized controlled trials are warranted to further evaluate the benefits of LVT prevention against the risks of major bleeding in this population.

Reduced-Dose Apixaban in the Treatment of Left Ventricular Thrombus: A Report of 2 Cases

According to the American College of Cardiology and the American Heart Association, warfarin has historically been the standard of care anticoagulant for the treatment of left ventricular thrombus. The use of direct oral anticoagulants (DOACs) has become more prevalent, as they require less frequent laboratory monitoring, offer fixed-dose regimens, are associated with fewer drug-drug and drug-food interactions, and provide more favorable safety profiles when compared to warfarin. However, DOACs are not currently FDA-indicated in the treatment of left ventricular (LV) thrombus. Numerous recent studies have reported and evaluated the use of DOACs for treatment of LV thrombus. Recently, a prospective, open-label, multicenter study evaluated warfarin compared to DOACs for LV thrombus treatment. The AHA recently published a scientific statement regarding the management of patients at risk for and with left ventricular thrombus, which included DOACs as a reasonable alternative to warfarin. This report describes two patients treated with DOACs following LV thrombus diagnosis. The first case is a 71-year-old male admitted for cerebrovascular accident and non-ST-elevation myocardial infarction complicated by a LV thrombus. The second case is an 83-year-old female admitted for acute myocardial infarction complicated with an LV thrombus. Both patients were prescribed apixaban 2.5 mg twice daily. Neither patient has experienced LV thrombus or DOAC treatment related complications. This case series serves as evidence for reduced-dose DOACs as an alternative to warfarin in the treatment of LV thrombus.

When Direct Oral Anticoagulants Should Not Be Standard Treatment: JACC State-of-the-Art Review

For most patients, direct oral anticoagulants (DOACs) are preferred over vitamin K antagonists for stroke prevention in atrial fibrillation and for venous thromboembolism treatment. However, randomized controlled trials suggest that DOACs may not be as efficacious or as safe as the current standard of care in conditions such as mechanical heart valves, thrombotic antiphospholipid syndrome, and atrial fibrillation associated with rheumatic heart disease. DOACs do not provide a net benefit in conditions such as embolic stroke of undetermined source. Their efficacy is uncertain for conditions such as left ventricular thrombus, catheter-associated deep vein thrombosis, cerebral venous sinus thrombosis, and for patients with atrial fibrillation or venous thrombosis who have end-stage renal disease. This paper provides an evidence-based review of randomized controlled trials on DOACs, detailing when they have demonstrated efficacy and safety, when DOACs should not be the standard of care, where their safety and efficacy are uncertain, and areas requiring further research.

Safety and Efficacy of Direct Oral Anticoagulant in Addition to Antiplatelet Therapy After Acute Coronary Syndrome: A Systemic Review and Meta-analysis of 53,869 Patients

INTRODUCTION

Significant progress has been made in the management of patients with acute coronary syndrome (ACS) during the past few decades. However, the role of direct oral anticoagulants (DOACs) in post-ACS prophylactic therapy remains unknown. This study aims to assess the efficacy and safety of DOACs plus antiplatelet treatment (APT) after ACS.

METHODS

A systematic literature search was conducted to identify randomized clinical trials comparing DOACs plus APT with APT alone after ACS. The primary efficacy end points were cardiovascular mortality, myocardial infarction, all-cause mortality, and stroke and systemic embolization (SSE). The primary safety end point was major bleeding. The random-effects model was used to calculate relative risk (RR) and corresponding 95% CIs.

RESULTS

Nine trials with a total of 53,869 patients were identified, with 33,011 (61.2%) in the DOACs plus APT group and 20,858 (38.8%) in the APT alone group. The use of DOACs did not decrease the risk of cardiovascular death (RR = 0.87; 95% CI, 0.75-1.01; P = 0.08; I2 = 0%) or myocardial infarction (RR = 0.90; 95% CI, 0.80-1.02; P = 0.10; I2 = 6%). However, the risk of SSE was significantly lower in patients who received DOACs plus APT compared with APT alone (RR = 0.67; 95% CI, 0.50-0.90; P = 0.008). Moreover, all-cause mortality was significantly lower in the DOACs plus APT group (RR = 0.83; 95% CI, 0.71-98; P = 0.03; I2 = 0%). However, the risk of major bleeding was significantly higher in patients treated with DOACs plus APT compared with APT alone (RR = 2.53; 95% CI, 1.96-3.26; P < 0.01; I2 = 0%), as was the risk of nonmajor bleeding (RR = 2.27; 95% CI, 1.51-3.41; P < 0.01).

IMPLICATIONS

DOACs plus APT for the prevention of left ventricular thrombus in patients with ACS were associated with a lower risk of SSE and all-cause mortality but increased the risk of major and nonmajor bleeding. The benefits and risks of this approach should be weighed based on a patient's individual clinical characteristics.

Rationale and design of the direct oral anticoagulants for prevention of left ventricular thrombus after anterior acute myocardial infarction (APERITIF) trial

BACKGROUND

Anterior acute myocardial infarction (AMI) is associated with an increased risk of left ventricular (LV) thrombus formation. We hypothesized that adding low-dose oral rivaroxaban to the usual antiplatelet regimen would reduce the risk of LV thrombus in patients with large AMI.

STUDY DESIGN

APERITIF is an investigator-initiated, multicenter randomized open-label, blinded end-point (PROBE) trial, nested in the ongoing "FRENCHIE" registry, a French multicenter prospective observational study, in which all consecutive patients admitted within 48 hours of symptom onset in a cardiac Intensive Care Unit (ICU) for AMI are included (NCT04050956). Among them, patients with anterior ST-elevation-myocardial infarction (STEMI) or very high-risk non- ST-elevation-myocardial infarction (NSTEMI) patients with involvement of the left anterior descending artery are randomized into 2 groups: Dual Antiplatelet Therapy (DAPT) alone or DAPT plus rivaroxaban 2.5mg twice daily for 4 weeks, started as soon as possible after completion of the initial percutaneous coronary intervention/angiography procedure. The primary endpoint is the presence of LV thrombus at 1 month, as detected by contrast enhanced CMR (CE-CMR). Secondary endpoints include LV thrombus dimension (greatest diameter), the rate of major bleedings and major cardiovascular events at 1 month. Based on estimated event rates, a sample size of 560 patients is needed to show superiority of DAPT plus rivaroxaban therapy versus DAPT alone, with 80% power.

CONCLUSION

The APERITIF trial will determine whether, in patients with large AMIs, the use of rivaroxaban 2.5mg twice daily in addition to DAPT reduces LV thrombus formation, compared with DAPT alone.

CLINICALTRIALS

gov Identifier: NCT05077683.

Rivaroxaban, a direct inhibitor of coagulation factor Xa, attenuates adverse cardiac remodeling in rats by regulating the PAR-2 and TGF-β1 signaling pathways

Background

Factor Xa (FXa) not only plays an active role in the coagulation cascade but also exerts non-hemostatic signaling through the protease-activated receptors (PARs). This study aimed to investigate whether the FXa inhibitor, Rivaroxaban (RIV), attenuates adverse cardiac remodeling in rats with myocardial infarction (MI) and to identify the underlying molecular mechanisms it uses.

Methods

An MI model was induced in eight-week-old, male Wistar rats, by permanent ligation of the left anterior descending coronary artery. MI rats were randomly assigned to receive RIV or protease-activated receptors 2-antagonist (PAR-2 antagonist, FSLLRY) treatment for four weeks. Histological staining, echocardiography and hemodynamics were used to assess the cardioprotective effects of RIV. Meanwhile, pharmacological approaches of agonist and inhibitor were used to observe the potential pathways in which RIV exerts antifibrotic effects in neonatal rat cardiac fibroblasts (CFs). In addition, real-time PCR and western blot analysis were performed to examine the associated signaling pathways.

Results

RIV presented favorable protection of left ventricular (LV) cardiac function in MI rats by significantly reducing myocardial infarct size, ameliorating myocardial pathological damage and improving left ventricular (LV) remodeling. Similar improvements in the PAR-2 antagonist FSLLRY and RIV groups suggested that RIV protects against cardiac dysfunction in MI rats by ameliorating PAR-2 activation. Furthermore, an in vitro model of fibrosis was then generated by applying angiotensin II (Ang II) to neonatal rat cardiac fibroblasts (CFs). Consistent with the findings of the animal experiments, RIV and FSLLRY inhibited the expression of fibrosis markers and suppressed the intracellular upregulation of transforming growth factor β1 (TGFβ1), as well as its downstream Smad2/3 phosphorylation effectors in Ang II-induced fibrosis, and PAR-2 agonist peptide (PAR-2 AP) reversed the inhibition effect of RIV.

Conclusions

Our findings demonstrate that RIV attenuates MI-induced cardiac remodeling and improves heart function, partly by inhibiting the activation of the PAR-2 and TGF-β1 signaling pathways.

What's the optimal duration of anticoagulation in patients with left ventricular thrombus?

INTRODUCTION

Left ventricular thrombus (LVT) occurs in acute myocardial infarction and in ischemic and non-ischemic cardiomyopathies. LVT may result in embolic stroke. Currently, the duration of anticoagulation for LVT is unclear. This is an important clinical question as prolonged anticoagulation is associated with increased bleeding risks, while premature discontinuation may result in embolic complications.

AREAS COVERED

There are no randomized trial data regarding anticoagulation duration for LVT. Guidelines and expert consensus recommend anticoagulation for 3-6 months with cessation of anticoagulation if interval imaging demonstrates thrombus resolution. Cardiac magnetic resonance imaging (CMR) is more sensitive and specific compared to echocardiography for LVT detection, and may be appropriate for high-risk patients. Prolonged anticoagulation may be considered in unresolved protuberant or mobile LVT, and in patients with resolved LVT but persistent depressed left ventricular ejection fraction and/or myocardial akinesia or dyskinesia.

EXPERT OPINION

CMR will likely be increasingly used for LVT surveillance to guide anticoagulation duration. Further research is needed to determine which patients with persistent LVT on CMR benefit from prolonged anticoagulation.

Low dose rivaroxaban for the management of atherosclerotic cardiovascular disease

Atherosclerotic cardiovascular disease is characterized by some risk of major adverse events despite the availability of effective medical therapies for secondary prevention. There is emerging evidence suggesting that thrombin partly contributes to this residual risk. In fact, thrombin (i.e., activated coagulation factor II) triggers not only the conversion of fibrinogen to fibrin but also platelet activation and various pathways responsible for pro-atherogenic and/or pro-inflammatory effects through interaction with protease activated receptors. To reduce the risk associated with thrombin activation, oral anticoagulants antagonists of vitamin K showed promise, but were associated with unacceptable bleeding rates. Direct oral anticoagulants targeting the activated factors X and II carry a lower risk of bleeding than vitamin K antagonists. Rivaroxaban, a direct inhibitor of activated factor X approved at the dose of 20 mg once daily for the prevention of thromboembolic events, has been also investigated at a reduced dose of 2.5 mg twice daily in several alternative scenarios of atherosclerotic cardiovascular disease, in combination with standard of care. Current guidelines recommend that low-dose rivaroxaban is given in an adjunct to standard therapy to patients with stable atherosclerosis and acute coronary syndromes at low bleeding risk. Several studies are underway to evaluate its putative benefits in other clinical settings.

Direct Oral Anticoagulants for Stroke and Systemic Embolism Prevention in Patients with Left Ventricular Thrombus

In recent years, direct oral anticoagulants (DOAC) have accumulated evidence of efficacy and safety in various clinical scenarios and are approved for a wide spectrum of indications. Still, they are currently used off-label for left ventricular thrombus owing to a paucity of evidence. For the same reason, there is a lack of guideline indication as well. Our work is based on an exhaustive analysis of the available literature and provides a structured and detailed update on the use of DOACs in patients with left ventricle thrombus. The safety and efficacy of DOACs were analyzed in particular clinical scenarios. As far as we know, this is the first paper that analyzes DOACs in this approach.

Management of Patients at Risk for and With Left Ventricular Thrombus: A Scientific Statement From the American Heart Association

Despite the many advances in cardiovascular medicine, decisions concerning the diagnosis, prevention, and treatment of left ventricular (LV) thrombus often remain challenging. There are only limited organizational guideline recommendations with regard to LV thrombus. Furthermore, management issues in current practice are increasingly complex, including concerns about adding oral anticoagulant therapy to dual antiplatelet therapy, the availability of direct oral anticoagulants as a potential alternative option to traditional vitamin K antagonists, and the use of diagnostic modalities such as cardiac magnetic resonance imaging, which has greater sensitivity for LV thrombus detection than echocardiography. Therefore, this American Heart Association scientific statement was commissioned with the goals of addressing 8 key clinical management questions related to LV thrombus, including the prevention and treatment after myocardial infarction, prevention and treatment in dilated cardiomyopathy, management of mural (laminated) thrombus, imaging of LV thrombus, direct oral anticoagulants as an alternative to warfarin, treatments other than oral anticoagulants for LV thrombus (eg, dual antiplatelet therapy, fibrinolysis, surgical excision), and the approach to persistent LV thrombus despite anticoagulation therapy. Practical management suggestions in the form of text, tables, and flow diagrams based on careful and critical review of actual study data as formulated by this multidisciplinary writing committee are given.