Antithrombotic therapy in left ventricular thrombosis and systemic embolism

[Diagnostic approach and management of left intraventricular thrombus complicated by unexpected embolism : A case report]

Left ventricular thrombus (LVT) is a serious complication of both ischemic and non-ischemic cardiomyopathies, with a high risk of morbidity and mortality due to systemic embolism. We present the case of a 73-year-old man with a history of myocardial infarction who subsequently developed an apical thrombus. Seven years after the initial event, this thrombus caused a splenic infarction complicated by an abscessed hematoma. This case underlines the critical role of advanced medical imaging in the diagnosis of LVT and highlights the emerging therapeutic potential of direct oral anticoagulants. It also highlights the challenges of diagnosing and managing LVT and the importance of reviewing the latest evidence to refine and optimize therapeutic strategies.

Review of the Etiology, Diagnosis, and Management of Left Ventricular Thrombus

The incidence of left ventricular (LV) thrombus following acute myocardial infarction has declined significantly due to recent advancements in reperfusion and antithrombotic therapies. The development of LV thrombus depends on Virchow's triad: endothelial injury following myocardial infarction, blood stasis from LV dysfunction, and hypercoagulability. Diagnostic modalities for LV thrombus include transthoracic echocardiography and late gadolinium enhancement cardiac magnetic resonance imaging. Anticoagulation with direct oral anticoagulants or vitamin K antagonists for 3 months following initial diagnosis of LV thrombus remains the treatment of choice for LV thrombus. However, further evidence is needed to demonstrate the noninferiority of direct oral anticoagulants compared with vitamin K antagonists for the prevention of thromboembolic events.

Direct Oral Anticoagulants Versus Warfarin in the Treatment of Left Ventricular Thrombus

BACKGROUND

Use of direct oral anticoagulants (DOACs) for the treatment of left ventricular (LV) thrombus has gained considerable interest.

OBJECTIVE

We aimed to evaluate if DOACs are effective in the treatment of LV thrombus compared with warfarin.

METHODS

We evaluated the medical records of patients diagnosed with a new LV thrombus at a tertiary medical center. The primary outcome was the composite of thrombus persistence, stroke, or systemic embolism. We adjusted for potential confounders using multiple logistic regression. The safety outcome was the composite of hemorrhagic stroke or bleeding requiring blood transfusion.

RESULTS

A total of 129 patients were treated with warfarin and 22, with a DOAC. In unadjusted analysis, 54.3% of patients treated with warfarin met criteria for the efficacy outcome as compared with 40.9% of patients treated with a DOAC (P = 0.25). In adjusted analysis, no difference between groups was observed (odds ratio = 0.39; 95% CI = 0.14-1.06; P = 0.07 for DOAC vs warfarin). In all, 3.9% of patients treated with warfarin met safety criteria as compared with 4.5% of patients treated with a DOAC. A total of 8 patients in the warfarin group had a stroke or systemic embolism as compared with 0 patients in the DOAC group (P = 0.37).

CONCLUSION AND RELEVANCE

Our data suggest that DOACs may be reasonable alternatives for treatment of LV thrombus. When added to the totality of available studies, this study demonstrates that the effectiveness of DOACs in LV thrombus remains uncertain. Randomized clinical trials are needed.

Cardiac imaging in ischemic stroke or transient ischemic attack of undetermined cause: Systematic review & meta-analysis

BACKGROUND

Patients with ischemic stroke or transient ischemic attack (TIA) of undetermined cause often undergo cardiac imaging in search of a cardioembolic source. As the choice of the most appropriate imaging approach is controversial and therapeutic implications have changed over time, we aimed to identify in patients with "cryptogenic stroke or TIA" the yield of transthoracic or transesophageal echocardiography (TTE or TEE) and cardiac computed tomography (CT).

METHODS AND RESULTS

We performed a systematic review and meta-analysis according to the PRISMA guidelines. Included were studies that assessed consecutive patients with ischemic stroke or TIA of undetermined cause to evaluate the yield of TTE, TEE, or cardiac CT for detecting cardioembolic sources. For each type of cardioembolic source the pooled prevalence was calculated. Only six out of 1458 studies fulfilled the inclusion criteria (1022 patients). One study reported the yield of TTE, four of TEE, and one of both TTE and TEE; no study assessed cardiac CT. Mean patient age ranged from 44.3-71.2 years, 49.2-59.7% were male. TTE detected 43 cardioembolic sources in 316 patients (4 (1.3%) major, 39 (12.3%) minor), and TEE 248 in 937 patients (55 (5.9%) major, 193 (20.6%) minor). The most prevalent major cardioembolic source was left atrial appendage thrombus, yet results were heterogeneous among studies.

CONCLUSIONS

TTE and TEE infrequently detect major cardioembolic sources that require a change of therapy. Findings should be interpreted with caution due to the limited number of studies. A large-sized prospective clinical trial is warranted to support evidence-based decision-making.

A case report of acute Leriche syndrome: aortoiliac occlusive disease due to embolization from left ventricular thrombus caused by myocarditis

Background

Leriche syndrome is the triad of symptoms consisting of claudication, erectile dysfunction, and absence of femoral pulses. Inflammatory disease of the heart muscle, myocarditis, may occur because of immune system activation, drug exposure or infections.

Case presentation

A 31-year-old man with no previous medical history presented to the emergency department with acute back pain that had started suddenly during weightlifting, which was initially misdiagnosed as spinal disc herniation. The patient returned four hours later and a thoracoabdominal computed tomography showed a large thrombus in the aortoiliac region creating a total occlusion. Vascular surgery with embolectomy was immediately performed. Further investigation with echocardiography revealed deteriorated systolic dysfunction with marked hypokinesia and two large thrombi in the left ventricle. Cardiac magnetic resonance imaging showed late contrast enhancement of the inferolateral and septal regions, which indicated a recent myocarditis.

Conclusion

Myocarditis can result in multiple embolization with diverse organ manifestation including total occlusion of the aortoiliac arteries, which required urgent embolectomy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02031-4.

Rationale and design of a prospective multi-center randomized trial of EARLY treatment by rivaroxaban versus warfarin in ST-segment elevation MYOcardial infarction with Left Ventricular Thrombus (EARLY-MYO-LVT trial)

Background

Left ventricular thrombus (LVT), a common complication of acute ST-segment elevation myocardial infarction (STEMI), is associated with increased risk of systemic embolism and high mortality. Current STEMI guidelines recommend adding anticoagulant therapy to dual antiplatelet therapy (DAPT) if early-formulated LVT were detected, for which vitamin K antagonist (VKA) is the standard anticoagulant agent. The role of non-VKA oral anticoagulants (NOACs) in this scenario is uncertain.

Methods

The EARLY-MYO-LVT study will be a prospective, multi-center and randomized trial designed to investigate the efficacy and safety of rivaroxaban versus warfarin in the treatment of post-STEMI LVT. It will enroll 280 patients with STEMI who have developed LVT within the first month of symptom onset. They will be randomized at 1:1 ratio into the group of rivaroxaban 15 mg daily or VKA treatment (with targeted INR 2–2.5) on the basis of standard DAPT (100 mg daily aspirin plus 75 mg daily clopidogrel) for 3–6 months. The primary efficacy endpoint will be the probability of LVT resolution after 3-month triple therapy, and the principal safety outcome will be the incidence of major bleeding events during the treatment.

Discussion

The described study will systemically assess the efficacy and safety of NOACs-based anticoagulant therapy in the treatment of LVT subsequent to STEMI.

Trial registration

The EARLY-MYO-LVT trial (Clinical trial number: NCT03764241).

Anticoagulation combined with antiplatelet therapy in patients with left ventricular thrombus after first acute myocardial infarction

Aims

There are limited data about the optimal anti-thrombotic therapy for preventing embolism while minimizing bleeding events in patients with first acute myocardial infarction (AMI) complicated by left ventricular thrombus (LVT).

Methods and results

Among 2301 consecutive patients with AMI hospitalized between 2001 and 2014, we studied 1850 patients with first AMI who discharged alive to investigate clinical characteristics, incidence of systemic embolism (SE), and association between anticoagulation and embolic or bleeding events. Left ventricular thrombus was diagnosed by echocardiography, left ventriculography, or cardiac magnetic resonance imaging in 92 (5.0%) patients (62 ± 12 years). During a median follow-up period of 5.4 years (interquartile range 2.1-9.1 years), SE occurred in 15 of 92 patients with LVT (16.3%) and 51 of 1758 patients without LVT (2.9%), respectively. Kaplan-Meier analysis showed a significantly higher incidence of SE in the LVT group (log-rank test, P < 0.001). Multivariate analysis showed that LVT was an independent predictor of SE. Among the LVT patients treated with vitamin K antagonists (n = 84), we compared the patients with therapeutic range (TTR) ≥50% (n = 34) and those with TTR <50% (n = 50). Only one embolic event developed in the TTR ≥50% group and nine embolic events developed in the TTR <50% group (2.9% vs. 19%, P = 0.036). There was no difference in major bleeding events (TTR ≥50%; 9% vs. TTR <50%; 8%, P = 0.89).

Conclusion

Appropriate anticoagulation therapy may decrease the incidence of embolic events without increasing the incidence of bleeding events in patients with first AMI complicated by LV thrombus.

Use of dabigatran for treatment of left ventricular thrombus: A tertiary care center experience

OBJECTIVES

Direct oral anticoagulants (DOACs) are now replacing vitamin K oral anticoagulants (VKAs) owing to superior efficacy, rapid action, less bleeding, wider therapeutic range,and fewer food and drug interactions.Unfortunately, the available data on the use of DOACs, particularly dabigatran, for treatment of left ventricular thrombus (LVT) issparse. We have hereby presented the largest study on use of dabigatran in LVT.

METHODS

Retrospective data of patients having LVT as diagnosed by transthoracic echocardiography (TTE) was screened. Patients on dabigatran were included in the study and follow up data of 6 months was obtained through medical records.

RESULTS

Of the 15 patients included in the study, the most frequent etiology was ischemic heart disease (67%), including 7 patients of STEMI (47%), followed by non-ischemic cardiomyopathy in 5 patients (33%). Only one patient, with STEMI, developed mild gastrointestinal bleeding at 3 months. Complete clot resolution was seen in 2 patients (13%) at first week of follow up and total 5 patients (33%) at the end of second week. The rate of clot resolution at 1 month, 3 months, and 6 months were 80%, 93% and 100%, respectively. The median duration required for complete clot resolution was 30 days (IQR=14-30).

CONCLUSION

Dabigatran appears to be safe, highly efficacious and results in rapid LV clot resolution. DOACs may be a suitable alternative to warfarin in treatment of LV thrombus. However, larger studies are required to validate this hypothesis.

Left ventricular thrombosis in acute anterior myocardial infarction: Evaluation of hospital mortality, thromboembolism, and bleeding

BACKGROUND

Left ventricular thrombosis (LVT) is a well-known complication of acute myocardial infarction, most commonly seen in anterior wall ST-segment elevation myocardial infarction (STEMI). It is associated with systemic thromboembolism.

HYPOTHESIS

Our aim was to evaluate the impact of LVT on in-hospital mortality, thromboembolism, and bleeding in patients with anterior STEMI.

METHODS

Data was collected from the Nationwide Inpatient Sample where patients with a primary diagnosis of "Anterior STEMI" [ICD9-CM code 410.1] were included. Comparisons were made between patients with LVT [ICD9-CM code 429.79] vs those without using propensity score matching (PSM).

RESULTS

From 2002 to 2014, there were 157 891 cases of anterior STEMI. Among these, 649 (0.4%) had LVT. Post-PSM, there was no difference in in-hospital mortality between the groups with LVT and without (7.3% vs 8.6%). Thromboembolic event rate was higher with LVT compared to those without LVT (7.3% vs 2.1%). There was no difference in bleeding events between patients with LVT and those without (2.9% vs 3.2%). The baseline average length of stay in the group with LVT was longer than the group without LVT (7.9 ± 6.7 days vs 5.1 ± 6.0 days). The average hospitalization-related costs were also significantly higher among patients with LVT compared to those without (95 598 USD vs 66 641 USD per stay) at baseline.

CONCLUSION

Among patients hospitalized with anterior STEMI, presence of LVT is associated with increased thromboembolic events, average length of hospital stay and average cost of hospitalization. However, it is not associated with increased in-hospital mortality or bleeding events.

Resolution of left ventricular postinfarction thrombi in patients undergoing percutaneous coronary intervention using rivaroxaban in addition to dual antiplatelet therapy

Left ventricular (LV) thrombus is usually seen in situations with reduced LV function, and is mostly seen in patients with large anterior ST-elevation myocardial infarction (MI). Most embolic events, in patients with LV thrombus formation, occur within the first 3-4 months, thus the recommendations regarding the duration of anticoagulant therapy. According to guidelines, an oral vitamin K antagonist, warfarin, is being used as an anticoagulant for this period. Novel oral anticoagulants were found to be either non-inferior or superior compared with warfarin in prevention of thromboembolism in patients with non-valvular atrial fibrillation. However, the data about their role in the management of LV thrombus are limited to case reports. Here, we report on the dissolution of LV apical thrombus in 3 patients with anterior ST-elevation MI receiving dual antiplatelet therapy and rivaroxaban on a reduced dose for 3 months.

Ischemic Left Ventricular Perforation Covered by a Thrombus in a Patient Presenting with Cerebral Ischemia: Importance of Time-Sensitive Performance and Adequate Interpretation of Bedside Transthoracic Echography

If myocardial infarction remains silent, only clinical signs of complications may unveil its presence. Life-threatening complications include myocardial rupture, thrombus formation, or arterial embolization. In the presented case, a 76-year-old patient was admitted with left-sided hemiparesis. In duplex sonography, a critical stenosis of the right internal carotid artery was identified and initially but retrospectively incorrectly judged as the potential cause for ischemia. During operative thromboendarterectomy, arterial embolism of the right leg occurred coincidentally, more likely pointing towards a cardioembolic origin. Percutaneous interventions remained unsuccessful and local fibrinolysis was applied. Delayed bedside echocardiography by an experienced cardiologist demonstrated a discontinuity of the normal myocardial texture of the left ventricular apex together with an echodense, partly floating structure merely attached by a thin bridge not completely sealing the myocardial defect, accompanied by pericardial effusion. The patient was immediately transferred to emergency cardiac surgery with extirpation of the thrombus, aortocoronary bypass graft placement, and aneurysmectomy. This didactic case reveals decisive structural shortcomings in patient's admission and triage processes and underlines, if performed timely and correctly, the value of transthoracic echocardiography as a noninvasive and cost-effective tool allowing immediate decision-making, which, in this case, led to the correct but almost fatally delayed diagnosis.

Application of spectral computed tomography dual-substance separation technology for diagnosing left ventricular thrombus

OBJECTIVE

To investigate the value of spectral computed tomography (CT) dual-substance separation technology for diagnosing left ventricular (LV) thrombus.

METHODS

In this observational case-control study, spectral CT scans were conducted in patients with and without LV thrombi. Densities in the regions of the LV cavity, papillary muscles and LV thrombus were observed on 140 kVp mixed-energy and 70 keV single-energy images. Iodine and blood were chosen as the base material pair, the densities were observed and the iodine and blood concentrations were quantitatively measured.

RESULTS

A total of 24 patients were enrolled in this study. On iodine-based density images, both the LV thrombus and papillary muscles showed low-attenuation shadows. On blood-based density images, comparable high-density attenuation was found in the LV thrombus and LV cavity, while relative hypodensity was noted in the papillary muscles. Iodine and blood densities were significantly lower in papillary muscles than in the LV cavity. Iodine densities were significantly lower in the LV thrombus than the LV cavity, whereas blood densities in the two areas did not differ significantly.

CONCLUSIONS

Spectral CT dual-substance separation technology and its derived images of iodine- and blood- based densities provide a new, simple, and feasible semiquantitative method to detect LV thrombus that warrants further investigation.

Vitamin K antagonists in heart disease: current status and perspectives (Section III). Position paper of the ESC Working Group on Thrombosis--Task Force on Anticoagulants in Heart Disease

Oral anticoagulants are a mainstay of cardiovascular therapy, and for over 60 years vitamin K antagonists (VKAs) were the only available agents for long-term use. VKAs interfere with the cyclic inter-conversion of vitamin K and its 2,3 epoxide, thus inhibiting γ-carboxylation of glutamate residues at the amino-termini of vitamin K-dependent proteins, including the coagulation factors (F) II (prothrombin), VII, IX and X, as well as of the anticoagulant proteins C, S and Z. The overall effect of such interference is a dose-dependent anticoagulant effect, which has been therapeutically exploited in heart disease since the early 1950s. In this position paper, we review the mechanisms of action, pharmacological properties and side effects of VKAs, which are used in the management of cardiovascular diseases, including coronary heart disease (where their use is limited), stroke prevention in atrial fibrillation, heart valves and/or chronic heart failure. Using an evidence-based approach, we describe the results of completed clinical trials, highlight areas of uncertainty, and recommend therapeutic options for specific disorders. Although VKAs are being increasingly replaced in most patients with non-valvular atrial fibrillation by the new oral anticoagulants, which target either thrombin or FXa, the VKAs remain the agents of choice for patients with atrial fibrillation in the setting of rheumatic valvular disease and for those with mechanical heart valves.

Anticoagulation after anterior myocardial infarction and the risk of stroke

Background

Survivors of anterior MI are at increased risk for stroke with predilection to form ventricular thrombus. Commonly patients are discharged on dual antiplatelet therapy. Given the frequency of early coronary reperfusion and risk of bleeding, it remains uncertain whether anticoagulation offers additional utility. We examined the effectiveness of anticoagulation therapy for the prevention of stroke after anterior MI.

Methods and Findings

We performed a population-based cohort analysis of 10,383 patients who survived hospitalization for an acute MI in Ontario, Canada from April 1, 1999 to March 31, 2001. The primary outcome was four-year ischemic stroke rates compared between anterior and non-anterior MI patients. Risk factors for stroke were assessed by multivariate Cox proportional-hazards analysis. Warfarin use was determined at discharge and followed for 90 days among a subset of patients aged 66 and older (n = 1483). Among the 10,383 patients studied, 2,942 patients survived hospitalization for an anterior MI and 20% were discharged on anticoagulation therapy. Within 4 years, 169 patients (5.7%) were admitted with an ischemic stroke, half of which occurred within 1-year post-MI. There was no significant difference in stroke rate between anterior and non-anterior MI patients. The use of warfarin up to 90 days was not associated with stroke protection after anterior MI (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.37–1.26). The use of angiotensin-converting-enzyme inhibitors (HR, 0.65; 95% CI, 0.44–0.95) and beta-blockers (HR, 0.60; 95% CI, 0.41–0.87) were associated with a significant decrease in stroke risk. There was no significant difference in bleeding-related hospitalizations in patients who used warfarin for up to 90 days post-MI.

Conclusion

Many practitioners still consider a large anterior-wall MI as high risk for potential LV thrombus formation and stroke. Among a cohort of elderly patients who survived an anterior MI there was no benefit from the use of warfarin up to 90 days post-MI to prevent ischemic stroke. Our data suggests that routine anticoagulation of patients with anterior-wall MI may not be indicated. Prospective randomized trials are needed to determine the optimal antithrombin strategy for preventing this common and serious adverse outcome.

Determinants of left ventricular thrombus formation after primary percutaneous coronary intervention for anterior wall myocardial infarction

Previous studies have reported that left ventricular (LV) thrombus is a complication in 10-56% of ST-segment elevation acute anterior wall myocardial infarctions (AWMI). Data suggest that changes in acute myocardial infarction management such as early anticoagulation, thrombolysis, and most recently, primary percutaneous coronary intervention (PCI), may decrease thrombus occurrence. Early time to reperfusion has been shown to decrease mortality and improve LV function recovery. To determine if door-to-balloon time (DTBT) affects the incidence of LV thrombus, we retrospectively analyzed data on 43 consecutive patients who underwent successful PCI of a primary acute ST-segment elevation AWMI. Transthoracic echocardiography was performed for detecting LV thrombus and measuring LV ejection fraction (EF) within 5 days on all patients (average time: 2.17 days post event). Nineteen patients underwent PCI within 2 h of arrival to the Emergency Department (Group A, average 88 min) and 24 patients underwent PCI with DTBT of more than 2 h (Group B, average 193 min). Clinically significant LV thrombus was detected in 35% of all patients. The incidence of LV thrombus formation in Group A was not significantly different from that in Group B (42.1% vs. 29.0%, respectively; P = 0.52). The risk of LV thrombus was independent of in-hospital anticoagulation and medical management, peak enzyme levels, and LVEF but did relate to age (odds ratio = 1.96, 95% CI 1.03-3.73, P = 0.04 per decade). No embolic events in hospital were observed (average hospital stay 9.2 days). We conclude that the incidence of LV thrombus remains high despite PCI. Also, we find that DTBT in patients presenting with an ST-segment elevation AWMI does not affect the incidence of LV thrombus formation. Increased age, however, does appear to increase the risk of LV thrombus development.

Antithrombotic and interventional treatment options in cardioembolic transient ischaemic attack and ischaemic stroke

Peer-reviewed data pertaining to anti-thrombotic and interventional therapy for transient ischaemic attack (TIA) or ischaemic stroke patients with non-valvular atrial fibrillation, atrial flutter, interatrial septal abnormalities, or left ventricular thrombus were reviewed. Long-term oral anticoagulant therapy with warfarin is the treatment of choice for secondary stroke prevention following TIA or minor ischaemic stroke in association with persistent or paroxysmal non-valvular atrial fibrillation or atrial flutter. If warfarin is contraindicated, long-term aspirin is a safe, but much less effective alternative treatment option in this subgroup of patients with cerebrovascular disease. Management of young patients with TIA or stroke in association with an interatrial septal defect is controversial. Various treatment options are outlined, but readers are encouraged to include these patients in one of the ongoing randomised clinical trials in this area. It is reasonable to consider empirical anticoagulation in patients with TIA or ischaemic stroke in association with left ventricular thrombus formation following myocardial infarction or in association with idiopathic dilated cardiomyopathy. If warfarin is prescribed, one should aim for a target international normalised ratio of 2.5 (range 2-3) to achieve the best balance between adequate secondary prevention of cardioembolic events and the risk of major haemorrhagic complications.

Cardioversion in Patients with Left Ventricular Thrombus Is Not Associated with Increased Thromboembolic Risk

OBJECTIVES

The purpose of the study was to define the incidence of systemic embolism after cardioversion in patients with left ventricular (LV) thrombus.

BACKGROUND

The risk of systemic embolization after cardioversion in patients with an atrial thrombus is well known. However, data on thromboembolic events after cardioversion in patients with LV thrombus are limited because of hesitance to perform cardioversion in this population.

METHODS

Transthoracic and transesophageal echocardiograms acquired between January 1996 and October 2001 at our institution were reviewed for presence of LV thrombus in two orthogonal apical views. A total of 413 patients had echocardiographic evidence of LV thrombus. Medical records were reviewed for cardioversion performed within 3 weeks of the echocardiogram.

RESULTS

A total of 21 patients, age 66 +/- 10 years and ejection fraction 22 +/- 10% were identified. Cardioversion was indicated for atrial fibrillation in 8 (38%) and ventricular tachyarrhythmia in 13 (62%) patients, and was performed emergently in 5 (24%), electively in 8 (38%), and during electrophysiology study in 8 (38%) patients. The time interval between diagnostic echocardiographic study and cardioversion was 6 +/- 5 (range 1-18) days. All thrombi were located in the apical LV and were described as laminated (71%) and protruding (29%), and measured 0.7 +/- 0.4 x 1.6 +/- 0.8 cm. Before cardioversion, 17 (81%) patients were anticoagulated with warfarin or heparin. During clinical follow-up of up to 1 year (153 +/- 150 days) anticoagulation with warfarin was given to 15 (71%) patients. No patient had clinically apparent embolic event, including stroke, during hospitalization or during outpatient follow-up.

CONCLUSIONS

Embolism after cardioversion in patients with echocardiographic evidence of LV thrombus was not observed. Cardioversion seems to be safe and further prospective studies are needed to address this.

Treatment of left ventricular thrombi with a low molecular weight heparin

BACKGROUND

Once a diagnosis of left ventricular thrombus has been established, the classical attitude consists in the administration of unfractionated heparin relayed by oral anticoagulation therapy. However, the use of unfractionated heparins in this indication was only assessed in an open, non-randomized study with no control group, including 23 patients. On the other hand, although low molecular weight heparins are routinely used in some departments, there are no studies available concerning these agents in this indication. The aim of this study was to evaluate the feasibility of low molecular weight heparin therapy in patients with left ventricular thrombi.

METHODS

The study was a prospective, non-randomized, open-label trial. All patients with a new left ventricular thrombus diagnosed between September 2000 and September 2003 received enoxaparine 100 IU/kg twice daily for a mean duration of 13 days. A relay treatment with fluindione was initiated on day 5. The left ventricular thrombus outcome was followed for 3 weeks by bi-weekly transthoracic echocardiography.

RESULTS

26 left ventricular thrombi were diagnosed over the 3-year study period: 19 in post-infarct patients with a history of anterior myocardial infarction and 7 in patients with dilated cardiomyopathy. The mean thrombus area decreased from 2.30+/-0.32 to 0.36+/-0.11 cm2 (p<0.0001). Nineteen thrombi out of twenty-six (73%) disappeared during the treatment period. No thrombocytopenia or hemorrhagic events were observed. One transient ischemic attack was reported.

CONCLUSION

This preliminary study suggests that low molecular weight heparins are well tolerated and efficient in terms of left ventricular thrombi disappearance or size reduction.

Pulsed wave tissue Doppler-derived myocardial performance index for the assessment of left ventricular thrombus formation risk after acute myocardial infarction

BACKGROUND

Assessment of left ventricular (LV) thrombosis risk after acute myocardial infarction (AMI) is important because of potential embolic sequelae that are reduced by oral anticoagulant agents. The goal of this study was to investigate whether early assessment of LV systolic and diastolic performance with pulsed wave tissue Doppler ultrasound scanning (PWTD) predicts LV thrombosis after AMI.

METHODS

Two-dimensional and Doppler ultrasound scanning echocardiographic examinations were performed in 92 consecutive patients (age, 58 +/- 10 years; 11 women) with first anterior AMI within 24 hours after arrival to the coronary care unit. From the apical 4-chamber view, the mitral annular velocities were recorded at the lateral corner of the mitral annulus with PWTD. The myocardial performance index (MPI), which combines parameters of both systolic and diastolic ventricular function, was calculated from the PWTD recordings. To analyze LV thrombus formation, the 2-dimensional echocardiographic examination was repeated on days 3, 7, 15, and 30. The patients were divided in 2 groups according to LV thrombus formation.

RESULTS

LV thrombus was found in 32 of 92 patients (35%; group 1) and was not found in 60 patients (65%; group 2). The MPI was significantly higher in group 1 than in group 2 (0.73 +/- 0.20 vs 0.53 +/- 0.14; P <.001). When an MPI >0.6 was used as the cutoff, LV thrombus formation could be predicted with a sensitivity rate of 81%, a specificity rate of 73%, a positive predictive value of 62%, and a negative predictive value of 88%. In multivariate analyses, only MPI and LV wall motion score index were independent predictors of LV thrombus formation (P = .038 and P = .047, respectively).

CONCLUSIONS

The MPI derived with PWTD soon after admission appears to be a useful parameter for assessing the risk of LV thrombosis after AMI. Patients with an MPI >0.6 after AMI seem to be at a higher risk for thrombus formation.

[An elderly patients with ventricular aneurysm, thrombus in the aneurysm, and cerebral infarction 10 years after myocardial infarction]

A 75-year-old man had a 26-year history of hypertension and an 18-year history of effort angina pectoris. He suffered acute myocardial infarction at age 61. According to serial echocardiography, the initially hypokinetic segment of the left ventricular apex was transformed to an apical aneurysm over the course of 10 years (at age 71). Ten months later, a transient ischemic attack occurred, despite the administration of aspirin. At age 72, echocardiography revealed a hyperechoic lesion that was suspected to be a thrombus within the aneurysmal cavity. Cerebral infarction (right occipital lobe) occurred 13 years after myocardial infarction, at age 73. After warfarin therapy for 3 months, the thrombus-like echo in the left ventricular aneurysm disappeared.

Echocardiographic Recognition of Left Ventricular Mural Thrombus

Left ventricular (LV) mural thrombus is a well recognized complication of acute myocardial infarction. In survivors of infarction, its incidence is influenced by the location and magnitude of infarction: it occurs often in patients with large anterior Q wave infarctions, particularly in the presence of LV apical akinesis or dyskinesis. Although radionuclide imaging with indium-111-labeled platelets, computed tomography, and magnetic resonance imaging may be used to identify LV mural thrombus, two-dimensional echocardiography is the technique of choice for assessing its presence, shape, and size, and recent technical advances in echocardiographic methodology, such as high-frequency, short-focal-length transducers, have improved the echocardiographic assessment of LV mural thrombus. In the patient in whom a mural thrombus is identified, acute and chronic anticoagulation (with heparin and warfarin, respectively) is indicated: first, to prevent further thrombus formation and, second, to reduce the incidence of systemic embolization.

Intracardiac thrombus formation in cardiac impairment: the role of anticoagulant therapy

The presence of intracardiac thrombus has been associated with many diseases and clinical states, although cardiac impairment is commonly also present. Despite this, there continues to be a lack of consensus on which patients with cardiac impairment should have anticoagulant therapy. This review discusses the relationship between thromboembolism and cardiac impairment secondary to ischaemic heart disease, and suggests possible mechanisms, methods of diagnosis and therapeutic strategies for anticoagulation in such patients. In particular, warfarin has been established as thromboprophylaxis in certain subgroups of patients with cardiac impairment secondary to ischaemic heart disease. A large-scale randomised controlled trial in ambulant patients with cardiac impairment to evaluate the effectiveness of anticoagulant therapy and antiplatelet therapy is, however, long overdue.

Left ventricular mural thrombus after acute myocardial infarction

Left ventricular mural thrombus is a well-recognized complication of acute myocardial infarction. In survivors of infarction, the incidence with which mural thrombus occurs is influenced by the location and magnitude of infarction, so that it occurs commonly in those with large anterior Q-wave infarctions, particularly in the presence of a left ventricular aneurysm. Echocardiography, radionuclide imaging with indium-111 labeled platelets, computerized tomography, and magnetic resonance imaging may be used to identify a left ventricular mural thrombus. Acute and chronic anticoagulation with heparin and warfarin, respectively, is given to prevent further thrombus formation and to reduce the incidence of systemic embolization.

Left ventricular thrombosis during infancy: report of two cases

Two patients with left ventricular thrombosis diagnosed by echocardiography are presented. The first patient was a 6-week-old girl with supraventricular tachycardia. Cross-sectional echocardiography showed a rounded and mobile structure protruding from the left ventricular wall. The girl was in heart failure and had signs of peripheral embolization. After sinus rhythm had been restored the thrombus diminished gradually and the girl recovered. The second patient was a newborn boy with severe aortic stenosis and a large massive thrombus along the left side of the interventricular septum. The boy died after valvotomy, the post-mortem examination confirmed the diagnosis of a large thrombus. Left ventricular thrombosis is uncommon in neonates and infants but may appear secondary to abnormal hemodynamics.

The role of echocardiography in assessing the morphological response of left ventricular thrombus to anticoagulation

We present a patient with idiopathic dilated cardiomyopathy and a large left ventricular apical thrombus in which serial echocardiography over a 1-month period documented progressive enlargement of this mural thrombus. This case illustrates the dramatic progression of left ventricular thrombus size despite aggressive anticoagulation. In addition, the critical role of echocardiography in the diagnosis and follow-up of patients with left ventricular thrombus is emphasized.

Should all patients with dilated cardiomyopathy receive chronic anticoagulation?

OBJECTIVE

To review the mechanism of intracardiac thrombus formation, describe the risk of systemic thromboembolization, critically evaluate the literature regarding the use of oral anticoagulation, review the American College of Chest Physicians (ACCP) guidelines, and provide recommendations for oral anticoagulation in patients with dilated cardiomyopathy (DCM).

DATA SOURCES

English language clinical studies, abstracts, and review articles pertaining to oral anticoagulation and DCM.

STUDY SELECTION AND DATA EXTRACTION

Relevant human studies examining the role of anticoagulation for preventing systemic thromboembolism in patients with DCM.

DATA SYNTHESIS

Potential mechanisms and risk factors for systemic thromboembolization in patients with DCM are discussed. Studies evaluating the benefits and risks of chronic oral anticoagulation to prevent systemic thromboembolization are critiqued. Recommendations for oral anticoagulation in patients with DCM from the second and third ACCP Consensus Conferences are reviewed. Suggestions for study design of a new clinical trial are presented.

CONCLUSIONS

The second ACCP Consensus Conference recommended chronic anticoagulation for all patients with DCM, but the third conference did not address this issue. Review of demographic data from clinical trials demonstrates reluctance to use anticoagulation in all patients with DCM because of lack of support from prospective, controlled trials. Recent data from large clinical trials suggest that the risk of systemic embolization may be lower than previously believed. We recommend the use of chronic anticoagulation with warfarin in patients for whom the risk of embolism is greater than the risk of major bleeding, such as those with atrial fibrillation or previous systemic embolization. Lack of compliance with ACCP guidelines suggests that clinicians require additional information regarding the bleeding risk and systemic embolization rate reduction of chronic anticoagulation in patients with DCM who remain in normal sinus rhythm. It is only through prospective, controlled trials that this risk/benefit ratio to prevent systemic embolism in patients with DCM can be established.