Left ventricular thrombus formation after acute myocardial infarction

Comprehensive computational assessment of blood flow characteristics of left ventricle based on in-vivo MRI in presence of artificial myocardial infarction

BACKGROUND

Understanding the effects of cardiac diseases on the heart's functionality which is the purpose of many biomedical researches, directly affects the diagnostic and therapeutic methods. Myocardial infarction (MI) is a common complication of cardiac ischemia, however, the impact of MI on the left ventricle (LV) flow patterns has not been widely considered by computational fluid dynamics studies thus far.

METHODS

In this study, we present an insightful numerical method that creates an artificial MI on an image-based fluid-structure interactional model of normal LV to investigate its influence on the flow in comparison with the normal case. Seventeen different models were developed to evaluate the effects of location, percentage, myocardial material properties and dilation size of MI on the LV's performance, area strain, wall displacement, pressure-volume loop, wall shear stress and velocity field.

RESULTS

The results show that MI considerably changes blood flow features which are fully dependent on MI parameters. For the case of constant MI location, the effect of a decrease of infarcted myocardium stiffness, increase of dilation size and increase of MI percentage are mostly similar. Although the location differences of MI under other constant conditions have similar impact on the ejection fraction, they also lead to dissimilar variations in the LV flow pattern and other indicators.

CONCLUSIONS

The presented model showed a capable computational method for investigating various mechanical MI conditions with respect to cardiac flow pattern. The perspective of this model development seems to be an applicable tool for MI clinical diagnosis and prediction of complications related to MI.

Prevention of Left Ventricular Thrombus Formation and Systemic Embolism After Anterior Myocardial Infarction: A Systematic Literature Review

BACKGROUND

Anterior myocardial infarction (MI) with apical dysfunction is associated with an increased risk of left ventricular thrombus (LVT) formation and systemic embolism (SE). However, the role for prophylactic anticoagulation in current practice is a matter of debate.

METHODS

We conducted a systematic review of peer-reviewed original articles in either English or French on the benefit of combining anticoagulation with standard therapy for the prevention of LVT/SE after MI by searching PubMed, Ovid/MedLine/Embase, the Cochrane Library, and Google Scholar.

RESULTS

Of 7382 identified records, 14 were retained for analysis. Nine articles addressed anticoagulation for patients not treated with percutaneous coronary intervention (PCI). Another 5 included at least some patients treated with PCI. Only 1 study specifically addressed exclusively a primary PCI population. Some studies showed a benefit for combining anticoagulation with standard therapy in patients not treated with PCI, but results were inconsistent. No evidence of benefit was reported when PCI patients were included and 1 study reported a signal for net harm. There was important interstudy heterogeneity and methodological limitations. Studies were likely individually underpowered.

CONCLUSIONS

The available studies of LVT/SE prevention after MI lacked statistical power and are heterogeneous in terms of treatments, revascularization methods, background medical therapy, and study design. We conclude that there is presently no compelling evidence for or against combining anticoagulation with standard therapy for post-MI patients with apical dysfunction after primary PCI, and inconsistent evidence supporting prophylaxis after thrombolysis. An appropriately powered randomized trial is required to answer this clinically relevant question.

Interventricular septal hematoma following repair of a ventricular septal defect

An interventricular septal hematoma is a rare complication after patch closure of a ventricular septal defect (VSD). We describe three cases of interventricular septal hematomas following patch VSD and discuss their management.

Comprehensive Echocardiographic Evaluation of an Atypical Left Ventricular Mass with an Unusual Site of Attachment

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The comprehensive echocardiographic evaluation of a large, atypical left ventricular mass is presented.

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The case highlights the importance of careful assessment from multiple imaging planes, using both transthoracic and transesophageal imaging, in order to accurately characterize an intracardiac mass on echocardiography.

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In certain cases where further characterization of an intracardiac mass is required, cardiac magnetic resonance imaging could assist in differentiating cardiac thrombus from cardiac tumors.

Aneurysm-related ischemic ventricular tachycardia: safety and efficacy of catheter ablation

Left ventricular aneurysm (LVA) postmyocardial infarction (MI) might be an arrhythmogenic substrate. We examined the safety and efficacy of catheter ablation of LVA-related ventricular tachycardia (VT).Thirty-three consecutive patients who underwent primary catheter ablation of ischemic VT were divided into LVA group (11 patients, mean age 61.9 years, 10 men) and none LVA group. Acute procedural outcomes, complications, and long-term outcomes were assessed.In LVA group, average number of induced VTs were 3.2 ± 2.6 (range 1-7), clinical VTs were located in the ventricular septum scar zone in 4 (36.4%) patients, acute success was achieved in 7 (63.6%) patients, partial success in 3 (27.3%) and failure in 1 patient, while none LVA group showing a statistically similar distribution of acute procedural outcomes (P = 0.52). There were no major or life-threatening complications. VT-free survival rate at median 19 (1-44) months follow-up was numerically but not significantly lower in LVA versus none LVA group (48.5% vs 62.8%, log-rank P = 0.40).Catheter ablation of ischemic VT in the presence of LVA appears feasible and effective, with about one-third of cases having septal ablation targets. Further studies are warranted.

Simultaneous Left Ventricular and Deep Vein Thrombi Caused by Protein C Deficiency

Protein C deficiency is a risk of venous thrombosis because of poor fibrinolytic activity. It remains controversial whether protein C deficiency causes arterial thrombosis. A 21-year-old woman was referred with a chief complaint of right leg pain and numbness. Contrast-enhanced computed tomography revealed a low-density mass in the left ventricle (LV), splenic infarction, and peripheral arterial obstructions in her right leg. Thrombosis extending from the renal vein to the inferior vena cava was also detected. Electrocardiography revealed ST depression in leads II, III, and aVF. Transthoracic echocardiography revealed hypokinesis of the apex and interventricular septum and a hypoechoic mass in the LV (26 × 20 mm). She was diagnosed with acute arterial obstruction caused by the LV thrombus, which might have resulted from previous myocardial infarction. Protein C activation turned out to be low (41%) 5 days after admission. The anticoagulant therapy was switched from heparin to rivaroxaban 16 days after admission. The LV thrombus disappeared 24 days after initial treatment, and she has had no thrombotic episodes for 2.8 years under rivaroxaban therapy. Thrombophilia should be investigated for cases of simultaneous left ventricular and deep venous thrombi. Rivaroxaban can be effective in prevention of further thrombotic events.

Clinical predictors and outcomes of patients with left ventricular thrombus following ST-segment elevation myocardial infarction

We aimed to characterize the independent predictors of LVT following STEMI and the association with outcomes. The clinical predictors of left ventricular thrombus (LVT) formation after ST-segment elevation myocardial infarction (STEMI) are not well-defined in the contemporary era. We performed a retrospective analysis of STEMI patients at Duke from 2000 to 2011 who had a transthoracic echocardiogram within 90 days post-STEMI and compared patients with and without LVT (LVT+ vs. LVT-). Univariate Cox proportional hazards regression models of baseline characteristics were examined and significant variables were used in a multivariable model to assess adjusted relationships with LVT. A multivariable Cox PH survival model with covariate adjustments was used for assessment of LVT and long-term mortality. Of all eligible patients, 1734 patients met inclusion criteria and 4.3 % (N = 74) had a LVT. LVT+ patients tended to have a history of heart failure (HF) and higher initial troponin compared to LVT- patients. After adjustment, higher heart rate, non-white race, HF severity, and presence of left anterior descending artery (LAD) disease were independent predictors of LVT. There was a trend toward an association between LVT and increased all-cause mortality (HR 1.36; 95 % CI 0.84-2.21, P = 0.22), however this was not statistically significant. LVT was seen in over 4 % of this contemporary post-STEMI population. Several baseline characteristics were independently associated with LVT: Heart rate, HF severity, LAD disease, and non-white race. Prospective studies are warranted to determine whether anticoagulation in patients at increased risk for LVT improves outcomes.

Review of Venoarterial Extracorporeal Membrane Oxygenation and Development of Intracardiac Thrombosis in Adult Cardiothoracic Patients

Venoarterial extracorporeal membrane oxygenation (VA ECMO) has become an indispensable treatment option for adult cardiothoracic patients experiencing acute refractory cardiogenic shock. VA ECMO is not without inherent complications as in-hospital mortality has ranged from 45% to 65% (1-3). Intracardiac thrombosis (ICT) is a rare but life-threatening complication associated with VA ECMO. VA ECMO cases complicated by ICT were searched for using the MEDLINE (PubMed and OVID), Society of Cardiovascular Anesthesiology Headquarters, and Google Scholar databases. Twelve cases of VA ECMO-associated ICT were discovered for review. Indications for VA ECMO were postcardiotomy cardiogenic shock and heart failure. The primary location of thrombus was the left ventricle and aortic root. Majority of the cases did not report subtherapeutic systemic anticoagulation. Two patients survived after the development of ICT. VA ECMO-associated ICT is a devastating consequence with high mortality. The majority of ICT occurred in cases with perceived adequate anticoagulation, but this may not result in complete suppression of the coagulation response. Continued exposure to procoagulant stimuli and worsening ventricular function and intracardiac stasis can shift the balance toward a hypercoagulable state and development of thrombosis.

Neutrophil Lymphocyte Ratio as a Predictor of Left Ventricular Apical Thrombus in Patients with Myocardial Infarction

BACKGROUND AND OBJECTIVES

In this study, we examined the role of inflammatory parameters in an apical mural thrombus with a reduced ejection fraction due to large anterior myocardial infarction (MI).

SUBJECTS AND METHODS

A total of 103 patients who had suffered from heart failure, 45 of whom had left ventricular apical thrombus (AT) after a large anterior MI, were enrolled in the study. A detailed clinical history was taken of each participant, biochemical inflammatory markers, which were obtained during admission, were analyzed and an echocardiographical and angiographical evaluation of specific parameters were performed.

RESULTS

There were no statistically significant differences in terms of age, gender, and history of hypertension, diabetes mellitus, and atrial fibrillation between both groups (p>0.05). Similarly there were no statistically significant differences in terms of biochemical and echocardiographic parameters (p>0.05). However, there were significant differences in terms of neutrophil lymphocyte ratio (p=0.032). After a multivariate regression analysis, neutrophil lymphocyte ratio (NLR) was an independent predictor of thrombus formation (β: 0.296, p=0.024). The NLR >2.74 had a 78% sensivity and 61% specifity in predicting thrombus in patients with a low left ventricular ejection fraction.

CONCLUSION

In this study, neutrophil lymphocyte ratios were significantly higher in patients with apical thrombus.

A coupled chemo-fluidic computational model for thrombogenesis in infarcted left ventricles

A coupled chemo-fluidic computational model for investigating flow-mediated thrombogenesis in infarcted left ventricles (LVs) is proposed. LV thrombus (LVT) formation after the acute myocardial infarction (AMI) may lead to thromboembolic events that are associated with high mortality and morbidity, and reliable stratification of LVT risk is the key to managing the treatment of AMI patients. There have been several studies emphasizing the importance of LV blood flow patterns on thrombus formation; however, given the complex interplay between ventricular flow dynamics and biochemistry of thrombogenesis, current understanding is mostly empirical. In the present model, blood flow in the LV is obtained by solving the incompressible Navier-Stokes equations, and this is coupled to the biochemical modeling of the coagulation cascade, platelet activation, and fibrinogen polymerization. The coupled model is used to examine the effect of ventricular flow patterns on thrombogenesis in modeled ventricles. It is expected that the method developed here will enable in-depth studies of thrombogenesis in patient-derived infarcted LV models.

Catheter Ablation of Ventricular Tachycardia in the Presence of an Old Endocavitary Thrombus Guided by Intracardiac Echocardiography

BACKGROUND

Catheter ablation of ventricular tachycardia (VT) in patients with structural heart disease (SHD) is effective in prevention of arrhythmia recurrences. However, endocardial ablation may be challenging in the presence of organized left ventricular (LV) endocavitary thrombus. Our goal was to analyze the results of VT ablation in patients with identified old thrombus.

METHODS AND RESULTS

We reviewed clinical and procedural data of 344 consecutive patients who underwent VT ablation for SHD. Old endocavitary thrombus was identified in four patients by preprocedural transthoracic echocardiography (TTE) and in four more patients by intracardiac echocardiography (ICE). All together, the case series of eight patients with detectable thrombus is reported. All patients (one woman, age: 67 ± 7 years) had postinfarction aneurysm (20 ± 8 years after the index myocardial infarction) and the thrombus was well organized without mobile structures. Arrhythmogenic substrate could not be obviously targeted beneath the base of thrombus; however, catheter ablation was successfully performed in the close vicinity. A total of 2.4 ± 1.2 procedures were necessary to abolish VT recurrences. Epicardial ablation was performed in three of eight (38%) patients as a second elective procedure. No procedural or periprocedural complications were observed. During the follow-up of 14 ± 15 months, two patients (25%) had sporadic VT recurrences.

CONCLUSIONS

ICE seems to be more sensitive for the detection of LV thrombi compared to TTE and is helpful in real-time navigation of mapping/ablation catheter. Besides potential thromboembolic risk, large thrombus may prevent accessibility to the "critical" portion of arrhythmia circuit and epicardial ablation is required in selected cases.

The Influence of Apical Aneurysm on Left Ventricular Geometry and Clinical Outcomes: 3-Year Follow-Up Using Echocardiography

BACKGROUND

Left ventricular apical aneurysm (LVAA) is a serious complication associated with myocardial infarction. However, the effects of a previously formed LVAA on long-term left ventricular (LV) geometry and clinical outcomes have not been fully evaluated.

METHODS

From January 2009 to May 2015, we retrospectively identified 70 patients (mean age, 66 ± 12 years; males, 72.9%) with an LVAA due to ischemia. These patients were classified into two groups according to the initial apical conicity ratio (ACR): large LVAA group (ACR ≥ 1.5, n = 40) and small LVAA group (ACR < 1.5, n = 30). An adverse outcome was defined as a composite of fatal arrhythmia, embolic infarction, and readmission due to heart failure.

RESULTS

The ACR significantly decreased over the first month and then increased after 1 and 3 years of follow-up. The other examined echocardiographic indexes did not exhibit temporal changes. During the follow-up period (median 1138 days), the large LVAA group experienced a lower event-free survival (P = 0.016). In a multivariate Cox model, the presence of a large LVAA (adjusted hazard ratio [HR] = 2.795, 95% confidence interval [CI] = 1.118-6.986, P = 0.028) and the initial LV ejection fraction (EF) (adjusted HR = 0.964, 95% CI = 0.932-0.997, P = 0.034) were independent predictors of adverse outcomes.

CONCLUSIONS

This study demonstrates that LVAAs undergo a dynamic process and that large LVAAs are associated with adverse outcomes. Our results suggest that the ACR could be helpful for predicting adverse outcomes in patients with apical aneurysm.

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.

Cardiovascular causes of emergency neurology presenting to an ICU

Stroke or transient ischemic attacks (TIA) represent an urgent clinical entity that is not limited only to elderly patients. The underlying causes of stroke and TIA are diverse, with those of cardiovascular origin being among the most prominent. This review seeks to elucidate some of the most important aspects of the disease in the context of emergency and critical care practice.

Incidence and Predictors of Left Ventricular Thrombus After Primary Percutaneous Coronary Intervention for Anterior ST-Segment Elevation Myocardial Infarction

BACKGROUND

The role of warfarin in anterior ST-segment elevation myocardial infarction (STEMI) complicated by left ventricular (LV) dysfunction in patients treated with primary percutaneous coronary intervention (PCI) and dual antiplatelet therapy is unclear. Warfarin may prevent cardioembolic events but significantly increases bleeding in the setting of dual antiplatelet therapy.

HYPOTHESIS

The incidence of LV thrombus in anterior STEMI patients treated with PCI is low, and clinical predictors might be valuable in determining patients at risk.

METHODS

We performed a retrospective, single-center study of 687 consecutive patients with anterior STEMI treated with PCI from 2006 to 2013. Baseline variables were evaluated in 310 patients at high risk for LV thrombus based on echocardiographic criteria. Patients with definite, probable, and no LV thrombus were compared by ANOVA, χ(2), or t test where appropriate. Logistic regression analysis was performed.

RESULTS

The incidence of LV thrombus was 15% (n = 47 probable/definite thrombus). Cardiac arrest was the only independent characteristic associated with increased risk of LV thrombus (odds ratio [OR]: 4.06, 95% confidence interval [CI]: 1.3-12.7). Trends were observed for a lower risk in cardiogenic shock (OR: 0.33, 95% CI: 0.10-1.05) and aspirin use at baseline (OR: 0.43, 95% CI: 0.17-1.1). Treatment variables associated with LV thrombus included unfractionated heparin use post-PCI (OR: 2.43, 95% CI: 1.16-5.1) and use of balloon angioplasty without stent.

CONCLUSIONS

In contemporary practice with primary PCI, definite LV thrombus following anterior STEMI with LV dysfunction is challenging to predict. Further investigation is needed to determine if there is a subset of patients that should be treated with prophylactic warfarin.

Incidence, diagnostic methods, and evolution of left ventricular thrombus in patients with anterior myocardial infarction and low left ventricular ejection fraction: a prospective multicenter study

BACKGROUND AND OBJECTIVES

We aimed to assess the incidence and evolution of left ventricular (LV) thrombi in a high-risk population of patients with LV systolic dysfunction after anterior myocardial infarction (ant-MI). We also compared the accuracy of transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging with contrast-delayed enhancement (CMR-DE) in detecting LV thrombi.

METHODS

We prospectively included 100 consecutive patients with LV ejection fraction (LVEF) <45% at the first TTE performed <7 days after ant-MI. A second evaluation with TTE and CMR-DE (by blinded examiners) was performed at 30 days. A third TTE and assessment of clinical status were performed between 6 and 12 months after ant-MI.

RESULTS

Patients (males 71%; mean age 59.1 ± 12.1 years; mean LVEF 33.5% ± 6.0%) were included at a median of 5.5 days (interquartile range 25th-75th percentile 4.25-6.0 days) after ant-MI. Thrombi were detected among 26 (26%) patients at a median of 12.0 days after ant-MI (7 patients at 1-7 days after MI; 15 at 8-30 days; and 4 after day 30). Sensitivity and specificity for LV thrombi detection were 94.7% and 98.5%, respectively, for TTE as compared with CMR-DE. Most thrombi (n = 24; 92.3%) disappeared after triple antithrombotic therapy (vitamin K antagonist in addition to dual antiplatelet therapy).

CONCLUSION

Left ventricular thrombus is a frequent complication after ant-MI with systolic dysfunction. When a search for thrombus is prespecified, the accuracy of TTE is high as compared with CMR-DE. The best antithrombotic strategy is not known.

Anticoagulation in Heart Failure: a Review

Heart failure (HF) with reduced left ventricular function inflicts a large and growing burden of morbidity and mortality in the US and across the globe. One source of this burden is stroke. While it appears that HF itself may impose some risk of stroke, it is in the presence of other risk factors, like atrial fibrillation, that the greatest risks are observed. Therapeutic anticoagulation is the mainstay of risk reduction strategies in this population. While warfarin was the only available therapy for anticoagulation for many decades, there are now four direct oral anticoagulants available. In three of these four, outcomes in the specific subgroup of patients with heart failure have been examined. In this review, we provide some pathophysiologic basis for the risk of stroke in heart failure. In addition, the available therapeutic options for stroke risk prevention in heart failure are described in detail including how these options are incorporated into relevant professional society guidelines.

Comparison of the usefulness of enoxaparin versus warfarin for prevention of left ventricular mural thrombus after anterior wall acute myocardial infarction

Left ventricular (LV) thrombus is one of the most common complications in patients with anterior acute myocardial infarction (AMI) and LV dysfunction. Although anticoagulation is frequently prescribed, data regarding the appropriate drug, duration, risks, and effect on echocardiographic indices of thrombus are lacking. Moreover, given the difficulty in obtaining adequate anticoagulation with warfarin, it is possible that short-term treatment with a more predictable agent would be effective. We randomized 60 patients at high risk of developing LV mural thrombus (anterior acute myocardial infarction with Q waves and ejection fraction≤40%) to receive either enoxaparin 1 mg/kg (maximum 100 mg) subcutaneously every 12 hours for 30 days or traditional anticoagulation (intravenous heparin followed by oral warfarin for 3 months). Clinical evaluations and transthoracic echocardiograms were obtained at baseline, in-hospital, and at 3.5 months. There were no differences between the groups regarding baseline demographics, acute echocardiographic findings, and in-hospital outcomes. The length of hospital stay tended to be shorter for the enoxaparin group (4.6 vs 5.6; p=0.066) and the corresponding hospital costs ($25,837 vs $34,666; p=0.18). At 3 months, bleeding and thromboembolic events were rare and similar between enoxaparin and warfarin groups. Although more patients had probable mural thrombus in the enoxaparin group compared with warfarin at 3.5 months (15% vs 4%; p=0.35), this was not significantly different. In conclusion, the use of enoxaparin tends to shorten hospitalization and lower cost of care. However, at 3.5 months, there appears to be numerically higher (but statistically insignificant) rates of LV thrombus in the enoxaparin group.

Post-PCI Antithrombotic Therapy in Patients Requiring Long-Term Anticoagulation

The number of patients who undergo percutaneous coronary intervention (PCI) and additionally require chronic anticoagulation for a variety of indications is not insignificant. The choice of antithrombotic therapy after PCI in patients with chronic indications for anticoagulation therapy remains a challenge for interventional cardiologists, as the risk of bleeding must be adequately weighed against the benefit of preventing future ischemic events. While these clinical scenarios are encountered in approximately 10 % of patients undergoing PCI, current practice guidelines do not sufficiently guide physicians as to how to best treat these PCI patients requiring chronic anticoagulation. Notwithstanding the clinical difficulties of treating such patients, there are several recent studies and analyses that have assessed optimal antithrombotic strategies in the PCI population, and there are several others that are currently underway. This review evaluates the currently available data and clinical scenarios commonly encountered by treating physicians.

Trans-aortic endoscopic ventricular thrombectomy in a patient with HIT and concomitant Aortic and ventricular thromboses

Dual aortic and ventricular thrombi are rare following myocardial infraction. We report the case of a 56-year-old man who initially denied primary percutaneous coronary intervention as a result of psychological phobia. Initial pharmacological management by thrombolysis and heparin was followed by multiple arterial thromboses including those of the left ventricle and right iliac artery with a subsequent diagnosis of heparin-induced thrombocytopaenia. Ensuing surgical management revealed the unanticipated finding of an additional aortic sinus thrombosis that was excised. The left ventricular thrombus was removed endoscopically to prevent ventricular incisions. This case emphasizes the technical advantages of video-endoscopic management of intracardiac thrombi and highlights the unexpected nature of multiple thromboses associated with heparin-induced thrombocytopaenia.

Multimodality cardiac imaging of a left ventricular thrombus: a case report

Background

Left ventricular thrombus (LVT) formation occasionally complicates patient recovery post myocardial infarction, conveying a significant risk of systemic embolism. Accordingly, thrombus detection and subsequent anticoagulation is imperative in order to minimize patient morbidity and mortality. Transthoracic echocardiography (TTE) is the imaging modality most widely used to screen for thrombus formation despite its suboptimal sensitivity and specificity.

Case presentation

This report describes the discordant imaging findings of a LVT in a 56 year old Caucasian male with an anterior ST elevation myocardial infarction. Left ventriculography revealed a filling defect, suggestive of a potential left ventricular (LV) thrombus, which could not be confirmed by TTE. Cardiac magnetic resonance imaging (MRI) demonstrated evidence of a full thickness scar involving the mid to distal anterior wall and apical regions, with confirmation of a small LV apical thrombus.

Conclusions

This case illustrates the limitations of TTE when used as a tool to screen for thrombus formation. It highlights the importance of multimodality cardiac imaging for the detection of post myocardial infarction (MI) complications, in the context of a high clinical suspicion.

Takotsubo's cardiomyopathy with an uncommon complication: implications for management and treatment

We present the case of a 57-year-old female with no significant history of cardiac disease admitted to our service with stress-induced cardiomyopathy (Takotsubo's cardiomyopathy). Admission echocardiography with contrast showed a non-mobile apical-filling defect, consistent with laminar thrombus. After 1 month of anticoagulation with warfarin (bridged with inpatient intravenous heparin), follow-up echocardiography with contrast showed resolution of the thrombus. Although reported in the literature, to our knowledge, there are no consensus guidelines for the surveillance and treatment of left ventricular thrombus in patients with Takotsubo's cardiomyopathy. An awareness of this adverse effect and its treatment implications is imperative for any clinician caring for these patients.

Postprocedural anticoagulation for specific therapeutic indications after revascularization for ST-segment elevation myocardial infarction (from the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction Trial)

Postprocedural anticoagulation (AC) after primary percutaneous coronary intervention (PCI) in ST-segment elevation myocardial infarction (STEMI) may be administered for a number of specific therapeutic indications (e.g. atrial fibrillation or left ventricular thrombus). However, the safety and effectiveness of such post-PCI AC for specific indications are not well defined. Thus, we sought to study outcomes after postprocedural AC for specific indications in patients undergoing primary PCI for STEMI in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial. Patients who underwent primary PCI for STEMI in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction trial were grouped according to whether they received specific indication AC. Adverse outcomes were assessed using propensity-adjusted multivariate analyses. After excluding patients who received post-PCI AC solely for routine prophylaxis, 410 patients (16.6%) received postprocedural AC for specific indications and 2,063 patients (83.4%) received no post-PCI AC. After propensity adjustment, use of postprocedural AC for specific indications was associated with higher rates of cardiac mortality, reinfarction, stent thrombosis, and major bleeding at 30 days compared with patients who received no AC post-PCI. In conclusion, in this large prospective study, use of postprocedural AC for specific indications after primary PCI for STEMI was independently associated with early rates of adverse ischemic and hemorrhagic outcomes. Post-PCI AC for specific indications was also associated with worse outcomes from 30 days to 3 years. Further studies are warranted to determine the optimal use of postprocedural AC after primary PCI in STEMI.

Myocardial infarction complicated by left ventricular thrombus and fatal thromboembolism following abrupt cessation of dabigatran

Novel anticoagulants are increasingly utilised in lieu of warfarin to treat non-valvular atrial fibrillation. Their clinical use in other non-FDA approved settings is also increasing. We present a case in which a patient abruptly stopped taking dabigatran due to a small bowel obstruction and shortly thereafter suffered a myocardial infarction complicated by left ventricular thrombosis with fatal embolisation to the superior mesenteric artery. In this context, we discuss the possibility of a rebound phenomenon of hypercoagulability with abrupt cessation of novel anticoagulants.

Incidence and predictors of early left ventricular thrombus after ST-elevation myocardial infarction in the contemporary era of primary percutaneous coronary intervention

The aim of this study was to define the incidence of left ventricular thrombus (LVT) and its predictors in the contemporary era of primary percutaneous intervention (pPCI) and contrast echocardiography. We retrospectively analyzed 1,059 patients presenting with ST-elevation myocardial infarction (STEMI) to our tertiary cardiac center and treated with pPCI. Preprocedural pharmacology and procedural technique (including access route, the use of drug-eluting stents, and thrombectomy) were at the operators' discretion. Transthoracic echocardiography was performed before discharge; echo contrast agent was used when appropriate. LVT was detected in 42 subjects (4%). There were no significant differences in baseline demographics or pre-PCI clinical features between the 2 groups. Post-treatment, mean ejection fraction (EF) in patients with LVT was 35±8.4% and in those without LVT was 47±10%, p<0.001. Thirty-seven patients (88%) in the LVT group presented with an anterior STEMI versus 471 patients (42%) in the without LVT group (p<0.001). Apical akinesis was noted in all patients with LVT irrespective of the principal location of the MI. Multivariate analysis predictors of LVT were reduced EF, anterior site of MI, and the use of platelet glycoprotein IIb/IIIa inhibitors. After diagnosis of LVT, patients were treated with warfarin for 3 to 6 months. No significant difference in mortality was detectable at discharge between the 2 groups. In conclusion, in the contemporary era of pPCI, the incidence of LVT in patients with STEMI is significantly lower than that of the previous (thrombolysis) literature. The early presence of LVT is more likely in patients with anterior STEMI (involving the apex) and reduced EF.

Left ventricular thrombus development during ventricular fibrillation and resolution during resuscitation in a swine model of sudden cardiac arrest

BACKGROUND

Intracardiac thrombus is a well-known complication of low-flow cardiac states including acute myocardial infarction and atrial fibrillation. Little is known, however, about the formation of intracardiac (left ventricular [LV]) thrombus during the extreme low-flow state of cardiac arrest.

OBJECTIVE

Using a swine model of sudden cardiac arrest, we examined the sonographic development of LV thrombus over time after induction of ventricular fibrillation (VF) and resolution of thrombus with cardiopulmonary resuscitation (CPR).

METHODS

This observational study was IACUC approved. Forty-five Yorkshire swine were sedated, intubated, and instrumented under general anesthesia before VF was electrically induced. Sonographic data was collected immediately after VF induction and at 2-min intervals thereafter. Following 12min of untreated VF, resuscitation was initiated with closed chest compressions using an oxygen-powered mechanical resuscitation device. Observations were continued during attempted resuscitation. At the end of the experiment, the animals were euthanized while still at a surgical depth of anesthesia. The data was analyzed descriptively.

RESULTS

Sonographic evidence of LV thrombus was observed in 43/45 animals (95.6% [95%CI: 85.2%, 98.8%]). Thrombus was detected within 6min in 39/45 (86.7% [95%CI: 73.8%, 93.8%]) animals that developed thrombus. Thrombus resolved within 2min after initiation of chest compressions in 31/43 (72.1% [95%CI: 57.3%, 83.3%]) animals.

CONCLUSION

Similar to other low-flow cardiac states, LV thrombus develops early in the natural history of VF arrest and resolves quickly once forward flow is re-established by chest compressions. Institutional protocol number: 154600-8.

Prevalence and Aetiology of Left Ventricular Thrombus in Patients Undergoing Transthoracic Echocardiography at the University of Maiduguri Teaching Hospital

Objectives. We sought to determine the prevalence and aetiology of LVT among patients undergoing echocardiography. Methods. We reviewed case notes and echocardiographic data of patient diagnosed with LVT using noncontrast transthoracic echocardiography. Definition of various conditions was made using standard guidelines. Mean ± SD were derived for continuous variables and comparison was made using Student's t-test. Results. Total of 1302 transthoracic echocardiograms were performed out of which 949 adult echocardiograms were considered eligible. Mean age of all subjects with abnormal echocardiograms was 44.73 (16.73) years. Abnormalities associated with LVT were observed in 782/949 (82.40%) subjects among whom 84/782 (8.85%) had LVT. The highest prevalence of 39.29% (33/84) was observed in patients with dilated cardiomyopathy, followed by myocardial infarction with a prevalence of 29.76% (25/84). Peripartum cardiomyopathy accounted for 18/84 (21.43%) cases with some having multiple thrombi, whereas hypertensive heart disease was responsible for 6/84 (7.14%) cases. The lowest prevalence of 2.38% (2/84) was observed in those with rheumatic heart disease. Left ventricular EF of <35% was recorded in 55/84 (65.48%). Conclusions. Left ventricular thrombus is common among patients undergoing echo, with dilated cardiomyopathy being the most common underlying aetiology followed by myocardial infarction. Multiple LVTs were documented in peripartum cardiomyopathy.

Paraganglioma as a rare cause of left ventricular thrombus in the setting of preserved ejection fraction: discussing the literature

Paragangliomas and pheochromocytomas are catecholamine-secreting tumours which if remain undiagnosed may cause severe morbidity and mortality. In rare circumstances these tumours can cause left ventricular (LV) thrombi to form by inducing cardiomyopathy and subsequent embolic complications. After a thorough literature review, six previous cases were found that presented the formation of an LV thrombus in the setting of a pheochromocytoma or paraganglioma. A majority of these cases were associated with significant wall motion abnormalities and their cardiac ejection fraction (EF) was compromised. This is a rare case of a patient developing LV thrombi in the setting of a paraganglioma with normal cardiac EF. We present this case to compare the similarities and differences of our case with previously reported cases and emphasise the importance of suspecting these LV thrombi in patients with these neuroendocrine tumours.