Cardiac thrombus in dilated cardiomyopathy. Relationship between left ventricular pathophysiology and left ventricular thrombus

Systemic right ventricle complications in levo-transposition of the great arteries: A case report and review of literature

BACKGROUND

Congenitally corrected levo-transposition of the great arteries (L-TGA) is a congenital heart disease in which the ventricles and great arteries are transposed from their typical anatomy. In L-TGA, the double discordance, atrioventricular and ventriculoarterial, create an acyanotic milieu which allows patients to survive their early decades, however, progressive systemic right ventricle (sRV) dysfunction creates complications later in life. sRV dysfunction and remodeling predisposes patients to intracardiac thrombus (ICT) formation.

CASE SUMMARY

A 40-year-old male with L-TGA presented with symptoms of acute decompensated heart failure. In childhood, he had surgical repair of a ventricular septal defect. In adulthood, he developed sRV dysfunction, systemic tricuspid valve (sTV) regurgitation, and left-bundle branch block for which he underwent cardiac resynchronization therapy. Transthoracic echocardiogram showed a sRV ejection fraction of 40%, severe sTV regurgitation, and a newly identified sRV ICT. ICT was confirmed by ultrasound-enhancing agents and transesophageal echocardiography. Our patient was optimized with guideline-directed medical therapy and diuresis. Anticoagulation was achieved with a vitamin K antagonist (VKA) and he was later referred for evaluation by advanced heart failure and heart transplant services.

CONCLUSION

Anticoagulation with VKA is the mainstay of treatment in the absence of conclusive data supporting direct oral anticoagulant use in ICT in patients with congenital heart disease. This case illustrates the natural history of L-TGA and highlights the importance of surveillance and monitoring with dedicated cardiac imaging to identify complications.

Mechanical thrombectomy in a young stroke patient with Duchenne muscular dystrophy

Background:

Duchenne muscular dystrophy (DMD) is an X-linked recessive skeletal muscle myopathy which is caused by mutations in the dystrophin gene. Lack of dystrophin also results to cardiomyopathy, which raises significantly the stroke risk in DMD-patients. However, data about therapeutic opportunities in the acute setting are scarce in literature. So far, only two cases receiving IV thrombolysis are described, one of them with fatal outcome.

Method:

Case report of a case of successful mechanical thrombectomy (MTE) in an acute ischemic stroke (AIS) patient with DMD and associated dilatative cardiomyopathy.

Results:

A 20-year old DMD-patient was transferred at 08:56 h to our department due to wake up stroke with severe right-sided hemiparesis and aphasia (NIHSS=20). Last-seen-normal was at 03:00 h. Cerebral CT-scan revealed only slight early ischemic changes (ASPECT-Score=8). CT-angiography detected occlusion of left middle cerebral artery (LMCA). MTE started rapidly at 9:23 h and using direct thrombus aspiration (Penumbra System®) complete recanalization was achieved 20 min later (TICI-grade 3). Considering the specific risks of general anesthesia in DMD, the procedure was performed with propofol, remifentanil and rocuronium. The patient recovered quickly from the acute symptoms, due to preexisting hypotonic tetraparesis his NIHSS-score at discharge was 12 points.

Conclusions:

To the best of our knowledge, this is the first report on MTE in a patient with DMD related cardioembolic stroke. In contrast to the few reports with IV thrombolysis, MTE seems to represent an optimal treatment option. Specific characteristics of DMD-patients like anesthetic regimen should be taken into account.

The neuropeptide galanin promotes an anti-thrombotic phenotype on endocardial endothelial cells from heart failure patients

Thromboembolic complications are a significant cause of mortality and re-hospitalization in heart failure (HF) patients. One source of thrombi is the ventricular endocardial surface that becomes increasingly pro-thrombotic as HF progresses. Anticoagulation comes with bleeding risks so identifying therapeutic agents for improving cardiac endothelial health are of critical clinical importance. Endocardial endothelial cells are closely apposed to cardiac sympathetic nerves. In HF, cardiac sympathetic nerves are dysregulated and promote disease progression. Whether endocardial endothelial health and function is impacted by sympathetic dysregulation in HF is unknown. Also unexplored is the impact of neuropeptides, such as galanin and neuropeptide Y (NPY), co-released from sympathetic nerve terminals, on endothelial health. In this study we examined the effect of sympathetic nerve-released neurotransmitters and neuropeptides on the procoagulant phenotype of cultured human endocardial endothelial cells from HF patients. As a functional readout of procoagulant state we examined thrombin-mediated von Willebrand factor (vWF) extrusion and multimer expression. We demonstrate that vWF extrusion and multimer expression is promoted by thrombin, that isoproterenol (a beta-adrenergic receptor agonist) augments this effect, whereas co-treatment with the beta-blockers propranolol and carvedilol blocks this effect. We also show that vWF extrusion and multimer expression is attenuated by treatment with the neuropeptide galanin, but not with NPY. Our results are consistent with a protective role of beta-blockers and galanin on endocardial endothelial health in heart failure. Improving endothelial health through galanin therapy is a future clinical application of this study.

Endocardial Endothelial Dysfunction Progressively Disrupts Initially Anti then Pro-Thrombotic Pathways in Heart Failure Mice

Objective

An experimental model of endocardial thrombosis has not been developed and endocardial endothelial dysfunction in heart failure (HF) is understudied. We sought to determine whether disruption of the endothelial anti-coagulant activated protein C (APC) pathway in CREB_A133 HF mice promotes endocardial thrombosis in the acute decompensated phase of the disease, and whether alterations in von Willebrand factor (vWF) secretion from HF endocardium reduces thrombus formation as HF stabilizes.

Approach and results

Echocardiography was used to follow HF development and to detect endocardial thrombi in CREB_A133 mice. Endocardial thrombi incidence was confirmed with immunohistochemistry and histology. In early and acute decompensated phases of HF, CREB_A133 mice had the highest incidence of endocardial thrombi and these mice also had a shorter tail-bleeding index consistent with a pro-thrombotic milieu. Both APC generation, and expression of receptors that promote APC function (thrombomodulin, endothelial protein C receptor, protein S), were suppressed in the endocardium of acute decompensated HF mice. However, in stable compensated HF mice, an attenuation occurred for vWF protein content and secretion from endocardial endothelial cells, vWF-dependent platelet agglutination (by ristocetin), and thrombin generation on the endocardial surface.

Conclusions

CREB_A133 mice develop HF and endocardial endothelial dysfunction. Attenuation of the anti-coagulant APC pathway promotes endocardial thrombosis in early and acute decompensated phases of HF. However, in stable compensated HF mice, disruptions in endothelial vWF expression and extrusion may actually reduce the incidence of endocardial thrombosis.

Interactions between cardiovascular and cerebrovascular disease

OPININION STATEMENT: All patients with ischemic stroke should undergo a comprehensive assessment of cardiovascular risk. Patients with carotid artery disease, symptoms of cerebral ischemia and high cardiovascular risk profiles should be considered for noninvasive testing for coronary artery disease (CAD). Routine testing for CAD before carotid endarterctomy is not recommended. Patients with coexisting coronary and carotid artery disease should be more aggressively treated for reducing their "very high" risk of cardiovascular events. In patients candidates to carotid revascularization, a preoperative coronary angiography and coronary revascularization are not recommended. Warfarin is recommended in all patients with moderate to high risk of stroke. Novel oral anticoagulants represent an attractive alternative to warfarin. However, their place in therapy in clinical practice is not yet established. Percutaneous closure of the left atrial appendage for stroke prophylaxis may be considered in selected patients with atrial fibrillation and contraindications for oral anticoagulant therapy. Warfarin is not indicated in patients with heart failure who are in sinus rhythm. Percutaneous closure of patent foramen does not seem to be superior to medical therapy for the prevention of recurrences in patients with cryptogenic stroke.

Presentation, management and outcomes of thrombosis for children with cardiomyopathy

BACKGROUND

Thrombosis in children with dilated and inflammatory cardiomyopathy is an unpredictable complication with potentially important morbidity.

OBJECTIVE

To determine the prevalence, associated factors, management and outcomes of thrombosis in this setting.

METHODS

Data were obtained from review of medical records. Factors associated with thrombosis and the impact on outcome were sought.

RESULTS

From 1990 to 1998, 66 patients that presented with dilated cardiomyopathy were followed for a median interval of 1.4 years (range 0 to 9.79 years) from first presentation. Thrombosis was diagnosed in four patients at presentation and in four patients during follow-up. Thrombosis was noted in one additional patient at examination after death. The overall nine-year period prevalence of thrombosis was 14%. Anticoagulation was started at presentation in 31% of patients. The mean left ventricular ejection fraction at presentation was significantly lower in those given anticoagulation (19+/-8%) versus those who were not (32+/-15%; P < 0.001). The mean ejection fraction at presentation was similar in those patients with (25+/-10%) versus those without thrombosis (28+/-15%; P = 0.44). During follow-up, 11 patients died and seven underwent cardiac transplantation. Kaplan-Meier estimates of freedom from death or transplantation were 88% at three months, 81% at one year and 70% at five years. Survival free of transplantation was not affected by thrombosis.

CONCLUSIONS

Thrombosis is common in children with cardiomyopathy, can occur at any time in the patients' clinical course and is not related to clinical features or survival free of transplantation. The relevance and prevention of thrombosis in this setting remains unclear.

Prophylaxis of thromboembolic events in congestive heart failure

In patients with heart failure the incidence of thromboembolism is 0.9-5.5%/year (mean 1.9%/year), but no randomized studies are available to support the indication for anticoagulant therapy in those patients. Atrial fibrillation and previous thromboembolic events seem to be the major risk factors, whereas the effect of ventricular dysfunction has not been independently evaluated; nonetheless several studies suggest that thromboembolism is more likely among those patients with lower ejection fraction and lower peak exercise oxygen consumption. Anticoagulant therapy seems to be indicated also in patients with left ventricular aneurysm with mobile and protruding thrombi. Several studies of patients with dilated cardiomyopathy show that the incidence of thromboembolism ranges from 1.6 to 4.5%/year in patients not treated with anticoagulants, while it is virtually absent in anticoagulated patients. The clinical opportunity of long-term anticoagulant treatment in heart failure patients should be weighted not only on the clinical markers of thromboembolic risk, but also on the relative risk/benefit ratio of the single patient.

Predictors of left ventricular thrombus formation in patients with dilated cardiomyopathy: role of activated protein C resistance

OBJECTIVES

The aim of this study was to investigate the association between left ventricular thrombus formation and natural anticoagulant systems including the protein C, protein S and antithrombin in patients with dilated cardiomyopathy.

MATERIALS AND METHODS

Sixty patients with dilated cardiomyopathy who met the inclusion criteria were included in the study. Patients were divided into two groups: group I consisted of 22 patients with left ventricular thrombus and group II consisted of 38 patients without left ventricular thrombus. Our main inclusion criteria were ejection fraction </= 35% and left ventricular end-diastolic diameter >/= 6.0 cm. These two groups were compared for clinical and hematologic parameters (activated protein C resistance, protein S and antithrombin).

RESULTS

There were no statistically significant differences between patients with or without left ventricular thrombi with respect to left ventricular end-diastolic and end-systolic dimensions, ejection fraction, fractional shortening and left atrial diameter. There were no statistically significant differences between patients with and without left ventricular thrombus with respect to platelet count (252 +/- 64/mm3 x 10(3) compared with 260 +/- 74/mm3 x 10(3) respectively, P=0.68), prothrombin time (12.94 +/- 1.9 s compared with 12.86 +/- 1.3 s respectively, P=0.82), activated partial thromboplastin time (32 +/- 5 compared with 30 +/- 4 s respectively, P=0.32) and fibrinogen levels (36 +/- 9 mg/dl compared with 34 +/- 8 mg/dl respectively, P=0.41). None of the patients had protein S and antithrombin deficiency. Activated protein C resistance was found in 12 patients (12 out of 22, 54%) in group I and four patients (four out of 38, 9.5%) in group II (P < 0.01). It was also shown to be an independent predictor of left ventricular thrombus (P < 0.05).

CONCLUSION

Activated protein C resistance is found to be an independent predictor of left ventricular thrombus in patients with dilated cardiomyopathy who have ejection fractions less then 35% and left ventricular end-diastolic dimensions > 6.0 cm.

Blood coagulation in patients with chronic heart failure: evidence for hypercoagulable state and potential for pharmacological intervention

Incidence data on thromboembolism in patients with heart failure (which may include stroke, peripheral embolism, pulmonary embolism) are limited but provide a general population range from 1-5 cases per 1000 each year, increasing with age to more than 30 cases per 1000 each year among people aged 75 years or older. However, the incidence of thromboembolism varied depending very much on what was being investigated in each of these studies. Data from subgroup analysis of the larger heart failure trials would seem to support this incidence data, although there is very little true epidemiological data and no randomised, controlled trial has been designed to specifically investigate thromboembolism in patients with heart failure. The pathophysiology of heart failure is complex. There are many well recognised factors which are associated with thrombosis in heart failure patients, such as vascular abnormalities, increased coagulability and impaired blood flow. In the past 50 years many studies have been performed to investigate if oral anticoagulation is of benefit for the prevention of thromboembolism in patients with heart failure. The use of warfarin therapy for heart failure patients has been a controversial subject. Warfarin does have a role to play in patients with myocardial infarction and those with atrial fibrillation. Furthermore, in patients with congestive heart failure secondary to coronary artery disease, warfarin reduces the occurrence of nonfatal myocardial infarction and, therefore, may reduce the chances of progression to heart failure. It has also been shown that warfarin reduces the risk of thromboembolic strokes in patients recovering from myocardial infarction. At present, there is a lack of randomised data, and the incidence of bleeding complications in patients with heart failure has caused a decrease in the use of oral anticoagulants for the prevention of thrombosis. This review summarises the incidence, potential mechanism and therapeutic approaches for management of thromboembolism in heart failure.

Hemostatic abnormalities in patients with congestive heart failure: diagnostic significance and clinical challenge

Knowledge of the pathogenesis of congestive heart failure (CHF) has improved greatly in recent years. However, this disease continues to cause one of the highest morbidities and mortalities in the Western world. The pathophysiology of heart failure is complex and much of our understanding revolves strictly around the neurohormonal mechanisms involved. Various pharmacologic interventions have significantly improved morbidity and include ACE inhibitors, beta-blockers, diuretics, and inotropic agents. Yet, no consensus has been reached regarding the use of anticoagulants or antiplatelet agents. It has been suggested that CHF is associated with altered hemostasis, but whether this prothrombotic state contributes to the pathogenesis and progression of the disease is unknown. The purpose of this review article is to discuss our current knowledge of platelet activation, thrombin generation, fibrinolysis, and endothelial dysfunction in CHF patients, and the potential role of anticoagulants and/or antiplatelet agents in preventing these hemostatic abnormalities.

Anticoagulation in Congestive Cardiomyopathy: Steps Toward Defining the Great Unknown

It is generally agreed that congestive cardiomyopathy predisposes to the formation of cardiac thrombus and in turn systemic thromboembolism. Several uncontrolled studies have confirmed this association and have prompted wide-scale recommendations for long-term anticoagulation in these patients. Clinical studies have also attempted to identify patients at high risk for embolic events. The presence of cardiac thrombus, its topographic characteristics, the severity of left ventricular dysfunction, and decreased apical flow velocities may each represent markers of increased risk.Driven by the lack of definitive data addressing this issue, several pleas from the medical community have come forth for a large, randomized controlled trial of anticoagulation in congestive cardiomyopathy. Accordingly, a multicenter trial comparing aspirin, warfarin, or placebo as prophylaxis against thromboembolism has been proposed and if conducted will provide valuable information regarding the management of patients with congestive cardiomyopathy.

Antiplatelet and anticoagulant therapy in the prevention of thromboemboli in chronic heart failure

Thromboembolism is an important complication in patients with heart failure. Several recent clinical trials have established the efficacy of anticoagulant therapy in patients with heart failure and atrial fibrillation. There is renewed interest in examining the role of antiplatelet and anticoagulation therapy in patients with heart failure in sinus rhythm. There is a need to identify patients at risk for thromboembolism in heart failure. However, there are data to suggest that occult thromboembolic events may contribute to disease progression, ischemic events, and sudden cardiac death. This review summarizes the incidence, potential mechanism, and therapeutic approaches for management of thromboembolism in heart failure.

Left Ventricular Thrombus After Pregnancy: Choice of Surgical Access Using Dynamic Three-Dimensional Echocardiography

Two idiopathic thrombi loosely attached to the left ventricular wall were detected by dynamic three-dimensional echocardiography. Because the thrombi were shown to be lobulated and extremely mobile, urgent surgical treatment was mandatory. Three-dimensional image reconstruction enhanced appreciation of left ventricular thrombi by enabling accurate imaging of the spatial relationship between the thrombus, the myocardial wall, and the valvular apparatus, so that the most advantageous surgical access could be chosen. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

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.