Use of apixaban for an elderly patient with left atrial thrombus

Absent Left Anterior Descending Coronary Artery as a Potential Cause of Ischemic Stroke: A Case Report

BACKGROUND Embolic stroke of undetermined source (ESUS) represents 20-30% of ischemic strokes, with a high risk of recurrence. It usually requires an extensive diagnostic evaluation to address the potential etiologies. Coronary artery anomaly (CAA) of the left anterior descending artery (LAD) is uncommon, and it is known to be linked to myocardial complications. The association of this anomaly with ischemic strokes has not been reported yet. Here, we report on a rare case of a young patient with hypoplastic LAD complicated by an impaired ventricular function that resulted in left ventricular (LV) thrombus formation as a source of recurrent ischemic strokes. CASE REPORT A 36-year-old man had a 4-year history of recurrent strokes despite maintaining antiplatelet treatment. He had no pre-existing vascular risk factors or relevant family history. The initial stroke etiology work-up was inconclusive. A transesophageal echocardiogram showed moderate ventricular hypokinesia. A coronary angiogram was initiated, and a hypoplastic (LAD) artery anomaly was found. At first, the antiplatelet therapy was maintained. Later on, he presented with transient focal neurological symptoms indicative of a transient ischemic attack. Repeated echocardiograms detected left ventricular thrombus. Apixaban was started, with successful thrombus resolution in a one-month follow-up echocardiogram. He has not had a further recurrent ischemic event for 18 months. CONCLUSIONS This case suggests that CAAs might be considered as an associated etiology of ESUS in a young patient with recurrent cerebral events. In a clinical setting, we encourage early use of advanced cerebral and cardiac imaging modalities to accurately determine the stroke etiology, target the appropriate treatment, and prevent a further neurological sequel.

Successful Resolution of a Large Left Atrial and Left Atrial Appendage Thrombus with Rivaroxaban

A 79-year-old male was admitted to the hospital for acute exacerbation of heart failure. The patient had history of atrial fibrillation and was planned for cardioversion. Preprocedure transesophageal echocardiogram (TEE) revealed a large multilobulated mobile thrombus in the left atrial appendage. The patient refused warfarin therapy and instead chose to take rivaroxaban. Upon outpatient follow-up, 3 months later, no visible thrombus was appreciated on repeat TEE. This case demonstrates successful resolution of left atrial and left atrial appendage thrombi with the use of rivaroxaban. At present time, limited data is available to support the use of rivaroxaban for treatment of intracardiac thrombi. This case highlights the need for further studies to investigate the outcomes and relative efficiency of use of direct oral anticoagulants (DOACs) in lysis of intracardiac thrombus. The benefits of DOACs compared to the standard of therapy could increase patient compliance, reduce length of stay, and improve treatment efficacy.

Prevalence and clinical characteristics associated with left atrial thrombus detection: Apixaban

BACKGROUND

The prevalence of left atrial appendage (LAA) thrombus detection by transesophageal echocardiogram (TEE) in patients with non-valvular atrial fibrillation (AF) anticoagulated with apixaban is not well defined and identification of additional risk factors may help guide the selection process for pre-procedural TEE. The purpose of our study was to retrospectively analyze the prevalence of LAA thrombus detection by TEE in patients continuously anticoagulated with apixaban for ≥ 4 wk and evaluate for any cardiac risk factors or echocardiographic characteristics which may serve as predictors of thrombus formation.

AIM

To retrospectively analyze the prevalence of LAA thrombus detection by TEE in patients continuously anticoagulated with apixaban.

METHODS

Clinical and echocardiographic data for 820 consecutive patients with AF undergoing TEE at Augusta University Medical Center over a four-year period were retrospectively analyzed. All patients (apixaban: 226) with non-valvular AF and documented compliance with apixaban for ≥ 4 wk prior to index TEE were included.

RESULTS

Following ≥ 4 wk of continuous anticoagulation with apixaban, the prevalence of LAA thrombus and LAA thrombus/dense spontaneous echocardiographic contrast was 3.1% and 6.6%, respectively. Persistent AF, left ventricular ejection fraction < 30%, severe LA dilation, and reduced LAA velocity were associated with thrombus formation. Following multivariate logistic regression, persistent AF (OR: 7.427; 95%CI: 1.02 to 53.92; P = 0.0474), and reduced LAA velocity (OR: 1.086; 95%CI: 1.010 to 1.187; P = 0.0489) were identified as independent predictors of LAA thrombus. No Thrombi were detected in patients with a CHA₂DS₂-VASc score ≤ 1.

CONCLUSION

Among patients with non-valvular AF and ≥ 4 wk of anticoagulation with apixaban, the prevalence of LAA thrombus detected by TEE was 3.1%. This suggests that continuous therapy with apixaban does not completely eliminate the risk of LAA thrombus and that TEE prior to cardioversion or catheter ablation may be of benefit in patients with multiple risk factors.

Successful resolution with apixaban of a massive left atrial appendage thrombus due to nonrheumatic atrial fibrillation: A case report and review

A 32-year-old woman with a past medical history of paroxysmal atrial fibrillation, long QT syndrome, and implantation of an automatic iimplantable cardioverter-defibrillator (AICD) following cardiac arrest presented with disabling symptoms of paroxysmal atrial fibrillation due to recurrent AICD shocks. Before curative ablation, transesophageal echocardiography was performed to assess for existing thrombi. This is a rare case of successful resolution with apixaban of a massive left atrial appendage thrombus due to non-rheumatic atrial fibrillation that was successfully treated with apixaban.

Left atrial thrombus despite continuous direct oral anticoagulant or warfarin therapy in patients with atrial fibrillation: insights into rates and timing of thrombus resolution

PURPOSE

Left atrial thrombus (LAT) may be detected by transesophageal echocardiography (TEE) in patients with atrial fibrillation (AF) or flutter (AFL) despite continuous anticoagulation therapy. We sought to examine the rates and timing of LAT resolution in response to changes in anticoagulation regimen.

METHODS

A retrospective study of 1517 consecutive patients on ≥ 4 weeks continuous oral anticoagulation (OAC) undergoing TEE prior to either direct current cardioversion or catheter ablation for AF or AFL was performed. Patients who had LAT on index TEE imaging and had follow-up TEEs were analyzed.

RESULTS

Despite ≥ 4 weeks of continuous anticoagulation therapy, 63 (4.2%) patients had LAT. Forty-four patients (median age 67 [IQR 58, 74]; 33 [75%] male; 25 [57%] on direct oral anticoagulant [DOAC]) had follow-up TEEs performed. Upon detection of LAT on index TEE, 8 patients switched from warfarin to a DOAC, 21 patients switched from a DOAC to warfarin or another DOAC, and 15 patients remained on the same OAC. Over median 4.2 months (IQR 2.9, 6.6), LAT resolution was seen in 25 (57%) patients. Of the 25 patients who had LAT resolution, 7 (28%) required TEE imaging > 6 months after index TEE to show clearance of thrombus. Rates of LAT resolution were similar between patients who had alterations in OAC and those who did not (52 vs. 60%; P = 0.601).

CONCLUSIONS

After initial detection of left atrial thrombus despite uninterrupted anticoagulation for atrial fibrillation or flutter, > 40% patients have persistent clot despite additional extended anticoagulation.

THROMBOSIS OF LEFT ATRIAL APPENDAGE DURING THERAPY WITH DIRECT ORAL ANTICOAGULANT. CLINICAL CASE

The article presents a clinical observation of the left atrial appendage thrombosis in a 51-year-old female patient with a paroxysmal form of nonvalvular atrial fibrillation which occurred despite long-term anticoagulant therapy with apixaban in a full dose (5 mg b.i.d.), and the patient’s management. The patient was admitted with recurrent symptomatic paroxysm for more than 48 hours, because of which, in accordance with the recommendations, transesophageal echocardiography was performed before an emergency rhythm restoration. Thrombus in the left atrial appendage 0.5×1.03 cm in size was detected. It was decided to refrain from the immediate restoration of the rhythm due to the very high risk of thromboembolic complications. In connection with the categorical refusal of the patient from warfarin, it was decided to replace apixaban with another direct oral anticoagulant – dabigatran 150 mg bid for a period of 4 weeks followed by performing a control transesophageal echocardiographic study. As a result, no thrombus was found on control echocardiography. The particularity of this observation is concomitant hypertrophic cardiomyopathy and diabetes mellitus type 1 in this patient.

Resolution of Left Atrial Appendage Thrombus with Apixaban in a Patient with Heart Failure

The effect of non-vitamin K antagonist oral anticoagulants on left atrial appendage (LAA) thrombus has not been fully elucidated. There are a few reports showing resolution of LAA thrombus with apixaban. An 84-year-old woman was admitted to our hospital due to acute exacerbation of chronic heart failure and marked tachycardia with atrial fibrillation. She had permanent atrial fibrillation and was treated with warfarin; however, transthoracic echocardiography revealed a non-mobile thrombus in the LAA. Therefore, we switched warfarin to apixaban at a dose of 5 mg/day. After two weeks on that therapy, the thrombus in the LAA was successfully resolved.

Left atrium mass in a patient with breast cancer: a case report

Background

Left atrial thrombi have traditionally been treated with heparin and warfarin, and many physicians have limited experience with direct oral anticoagulants such as apixaban. Furthermore, the efficacy of apixaban for the treatment of left atrial thrombi has not been established. We experienced a case of left atrial thrombus formation before breast cancer surgery, which was resolved by apixaban.

Case presentation

Computed tomography for a 74-year-old Japanese woman with breast cancer incidentally revealed a left atrial mass with a root before the breast surgery. The mass was surgically removed and determined to be a thrombus. Before the breast surgery, transthoracic echocardiography was performed again, and the left atrial thrombus had recurred within only 14 days. It resolved after administration of apixaban.

Conclusions

A left atrial thrombus might recur within a very short time. Apixaban might be an alternative to warfarin in patients with breast cancer and left atrial thrombus.

Left atrial thrombus resolution in atrial fibrillation or flutter: Results of a prospective study with rivaroxaban (X-TRA) and a retrospective observational registry providing baseline data (CLOT-AF)

BACKGROUND

Data on left atrial/left atrial appendage (LA/LAA) thrombus resolution after non-vitamin K antagonist (VKA) oral anticoagulant treatment are scarce. The primary objective of X-TRA was to explore the use of rivaroxaban for the resolution of LA/LAA thrombi in patients with nonvalvular atrial fibrillation (AF) or atrial flutter, with the CLOT-AF registry providing retrospective data after standard-of-care therapy in this setting.

METHODS

X-TRA was a prospective, single-arm, open-label, multicenter study that investigated rivaroxaban treatment for 6 weeks for LA/LAA thrombus resolution in patients with nonvalvular AF or atrial flutter and LA/LAA thrombus confirmed at baseline on a transesophageal echocardiogram (TEE). CLOT-AF retrospectively collected thrombus-related patient outcome data after standard-of-care anticoagulant treatment for 3 to 12 weeks in patients with nonvalvular AF or atrial flutter who had LA/LAA thrombi on TEE recorded in their medical file.

RESULTS

In X-TRA, patients were predominantly (95.0%) from Eastern European countries. The adjudicated thrombus resolution rate was 41.5% (22/53 modified intention-to-treat [mITT] patients, 95% CI 28.1%-55.9%) based on central TEE assessments. Resolved or reduced thrombus was evident in 60.4% (32/53 mITT patients, 95% CI 46.0%-73.6%) of patients. In CLOT-AF, the reported thrombus resolution rate was 62.5% (60/96 mITT patients, 95% CI 52.0%-72.2%) and appeared better in Western European countries (34/50; 68.0%) than in Eastern European countries (26/46; 56.5%).

CONCLUSION

X-TRA is the first prospective, multicenter study examining LA/LAA thrombus resolution with a non-VKA oral anticoagulant in VKA-naïve patients or in patients with suboptimal VKA therapy. Rivaroxaban could be a potential option for the treatment of LA/LAA thrombi.

Right ventricular thrombus formation in a patient with arrhythmogenic right ventricular dysplasia following radiofrequency ablation

A middle-aged female suffering from ARVD presented for routine follow-up 8 weeks after right ventricular radiofrequency ablation of recurring ventricular tachycardia. Echocardiography revealed two right ventricular thrombi in the scar area of right ventricular radiofrequency ablation. Ablation-related thromboembolic events should be considered as possible complication in patients suffering from ARVD.

Prevalence of Left Atrial Thrombus Detection by Transesophageal Echocardiography: A Comparison of Continuous Non-Vitamin K Antagonist Oral Anticoagulant Versus Warfarin Therapy in Patients Undergoing Catheter Ablation for Atrial Fibrillation

OBJECTIVES

The purpose of this study is to determine whether patients on ≥4 weeks of continuous non-vitamin K antagonist oral anticoagulant (NOAC) therapy require transesophageal echocardiography (TEE) before catheter ablation of atrial fibrillation (AF) or atrial flutter and to compare rates of left atrial (LA) thrombus and dense spontaneous echocardiographic contrast (SEC) in patients on NOAC versus warfarin therapy.

BACKGROUND

The impact of NOAC therapy on the rates of LA thrombus detection by TEE in patients undergoing catheter ablation of AF is unknown.

METHODS

Initial TEEs for 388 patients (median age, 65 years; 74% male) on ≥4 weeks of continuous NOAC (n = 183) or warfarin therapy (n = 205) undergoing catheter ablation of AF and flutter were reviewed.

RESULTS

After ≥4 weeks of therapy, the prevalence of LA thrombus and LA thrombus/dense SEC among patients on NOACs was 4.4% and 6.0%, respectively, which was comparable with that of patients on warfarin. LA thrombus rates among patients on dabigatran, rivaroxaban, and apixaban were 5.4%, 4.8%, and 0%, respectively (p = 0.46). Predictors of LA thrombus were congestive heart failure (odds ratio [OR]: 5.38; 95% confidence interval [CI]: 1.79 to 16.2; p = 0.003); and persistent AF (OR: 3.27; 95% CI: 1.06 to 10.2; p = 0.040).

CONCLUSIONS

Despite ≥4 weeks of anticoagulation, the rate of LA thrombus in patients on NOACs before catheter ablation of AF or atrial flutter was 4.4%. This suggests that continuous NOAC therapy does not eliminate the need for TEE before catheter ablation of AF.

Left Atrial Appendage Thrombus Resolution with Reduced Dose Apixaban

A 63 year old woman with a history of persistent atrial fibrillation and CHADSVASC score of 2, suffered a massive stroke with a hemorrhagic transformation, 2 days following an appendectomy and reversal of warfarin anticoagulation with vitamin K. A left atrial appendage occlusive device (LAAOD) was considered for stroke prevention given the risk of recurrent cerebral hemorrhage. A transesophageal echocardiography (TEE) however, revealed left atrial appendage (LAA) clots which precluded the use of a LAAOD. A computed tomography revealed only partial resolution of the right hemispheric hematoma. Apixaban 2.5 mg twice daily was successful in resolving the LAA clots within 2 months without aggravating her cerebral hematoma which continued to resolve. This is the first case, to our knowledge showing reduced-dose Apixaban to completely resolve left atrial thrombus. Our case also addresses the issue of bridging following reversal of warfarin anticoagulation with vitamin K.

Rationale and design of a study exploring the efficacy of once-daily oral rivaroxaban (X-TRA) on the outcome of left atrial/left atrial appendage thrombus in nonvalvular atrial fibrillation or atrial flutter and a retrospective observational registry providing baseline data (CLOT-AF)

There are still many unresolved issues concerning patient outcomes and prognostic factors in patients with atrial fibrillation (AF) and left atrial/left atrial appendage (LA/LAA) thrombi. Rivaroxaban (Xarelto®), a potent and highly selective oral, direct factor Xa inhibitor, is a new therapeutic option in this setting. The planned study program will consist of a prospective interventional study (X-TRA) and a retrospective observational registry (CLOT-AF). The primary objective of the X-TRA study is to explore the efficacy of rivaroxaban in the treatment of LA/LAA thrombi in patients with nonvalvular AF or atrial flutter, scheduled to undergo cardioversion or AF ablation, in whom an LA/LAA thrombus has been found on transesophageal echocardiography (TEE) before the procedure. The primary end point is the complete LA/LAA thrombus resolution rate at 6 weeks of end of treatment confirmed by TEE. The secondary objectives are to describe categories of thrombus outcome in patients (resolved, reduced, unchanged, larger, or new) confirmed on TEE at the end of treatment (after 6 weeks of treatment), incidence of the composite of stroke and noncentral nervous system systemic embolism at the end of treatment and during follow-up, and incidence of all bleeding at the end of treatment and during follow-up. The objective of the CLOT-AF registry is to provide retrospective thrombus-related patient outcome data after standard-of-care anticoagulant treatment in patients with nonvalvular AF or atrial flutter, who have TEE-documented LA/LAA thrombi. The data will be used as a reference for the prospective X-TRA study. In conclusion, X-TRA and CLOT-AF will provide some answers to the many unresolved issues concerning patient outcomes and prognostic factors in patients with AF and LAA thrombi. Results from this study program would provide the first prospective interventional study (X-TRA) and a large international retrospective observational registry (CLOT-AF) on the prevalence and natural history of LA/LAA thrombi. Unique data on clot resolution with rivaroxaban in a prospective cohort would be obtained in X-TRA.

Left atrial thrombus formation and resolution during dabigatran therapy: A Japanese Heart Rhythm Society report

BACKGROUND

Protocols on the use of novel oral anticoagulants for stroke prevention in patients with atrial fibrillation (AF) undergoing electrical cardioversion (ECV) are lacking.

AIM

The study was aimed at evaluating the efficacy of dabigatran (Dabi) treatment in preventing peri-ECV stroke.

METHODS

A retrospective survey of the incidence and fate of left atrial (LA) thrombus during Dabi therapy in patients with AF was conducted between December 2012 and January 2013 by the Japanese Heart Rhythm Society.

RESULTS

A total of 198 patients from 299 institutions underwent transesophageal echocardiography (TEE) to rule out LA thrombus before ECV. Of these, LA thrombus was found in eight patients (4%), who tended to be older (67.3 vs. 61.3 years, p=0.175), had higher CHADS2 scores (1.88 vs. 0.95, p=0.058), and a higher prevalence of prior stroke or transient ischemic attack (22.2% vs. 2.6%, p=0.034) than those without LA thrombus. Of the eight patients with LA thrombus, one had LA thrombus during a Dabi 150 mg b.i.d treatment, whereas the remaining seven were receiving 110 mg b.i.d for 3 weeks or longer. In 6 of the 8 patients with LA thrombus, a second TEE was performed, revealing complete resolution of LA thrombus in five; among these five patients, one received Dabi dosage of 150 mg b.i.d unchanged, two received an increased dosage from 110 mg to 150 mg b.i.d, and two were switched to warfarin. Two patients had a stroke 3 and 15 days after ECV, and one had a major large intestine bleeding episode during Dabi therapy.

CONCLUSIONS

LA thrombus developed in 4% of patients with AF receiving Dabi. Older patients with a higher CHADS2 score receiving a lower Dabi dosage were more likely to develop LA thrombus, which was resolved with a prolonged or increased dosage. A higher Dabi dosage may be more beneficial before ECV but prospective randomized studies would be needed to confirm these results.

Embolic stroke during apixaban therapy for left atrial appendage thrombus

Left atrial appendage (LAA) thrombus is associated with atrial fibrillation (AF) and is a powerful predictor of cardiogenic thromboembolism. Warfarin is an established anticoagulant therapy for patients with LAA thrombus to prevent thromboembolic complications. Apixaban is superior to warfarin in the prevention of thromboembolic complications in patients with AF, and there are case reports showing apixaban-associated resolution of LAA thrombus; however, the efficacy and safety of apixaban for the treatment of LAA thrombus remains unproven. Here we report a patient who experienced embolic stroke while taking apixaban for the treatment of LAA thrombus. Thrombolysis therapy was initiated at the onset of stroke and the patient recovered remarkably. Apixaban is known to make thrombi mobile and/or fragile by shifting the coagulation/fibrinolysis balance to a relative predominance of fibrinolytic activity; therefore, it is necessary to monitor for thromboembolic complications after the initiation of apixaban for the treatment of pre-existing LAA thrombus.