Aortic atherosclerotic plaques as a source of systemic embolism

Objectives. Our study was designed to determine the significance of aortogenic embolism in an unselected autopsy collective.Background. Although embolism arising from atherosclerotic plaques in the aorta has been acknowledged, the role of aortic atheromatosis among other well known sources of embolism remains to be further clarified.Methods. We examined the proximal part of the arterial system with regard to the presence of atherosclerotic lesions as well as cardiac changes in 120 consecutive necropsy studies. Pathologic evidence of embolic events was recorded. Clinical and neuropathologic data were also surveyed in all patients.Results. Among atherosclerotic lesions, fibrous plaques (p < 0.05) and calcified (p < 0.0001) and ulcerated lesions (p < 0.0001) as well as thrombi (p < 0.005) were observed significantly more frequently in the aortic arch and in the descending aorta than in the ascending aorta, whereas fatty streaks were distributed uniformly. In 40 (33%) of the 120 patients, we found pathologic evidence of arterial embolization. Multiple logistic regression analysis revealed a significant correlation between embolism and complicated atherosclerotic plaques in the aortic arch (odds ratio [OR] 5.8, 95% confidence interval [Cl] 1.1 to 31.7, p < 0.05), severe ipsilateral carotid artery disease (OR 3.1, 95% CI 3.1 to 45.3, p < 0.001) and atrial fibrillation (OR 3.5, 95% CI 1.1 to 9.9, p < 0.05).Conclusions. Complicated atherosclerotic plaques in the aortic arch represent an independent risk factor for systemic embolism similar to atrial fibrillation and severe atherosclerosis of the carotid arteries.     

Cardiogenic and aortogenic brain embolism

Cardioaortic brain embolism is a potentially devastating condition that presents frequent diagnostic and therapeutic challenges. In this report, we review key aspects of the etiology, clinical presentation, diagnosis, prognosis, and treatment of cardiogenic and aortogenic stroke. Emphasis is on advances in diagnostic imaging capabilities and on recent literature addressing secondary prevention for specific cardioembolic sources, upon which diagnosis and prognosis primarily depend. While early evaluation with modern neuroimaging techniques offers to enhance diagnostic accuracy, additional study is required to define optimal utilization. Appropriate imaging of the heart and aorta is paramount to identifying potential sources of embolism. Secondary prevention for high-risk embolic sources generally involves anticoagulation, but immediate initiation of anticoagulation is not routinely indicated. Medium-risk sources have more modest or undefined risks and little randomized comparative evidence to guide management, but antiplatelet therapy is generally favored. One possible exception is patent foramen ovale, for which high-risk features may warrant anticoagulation or mechanical closure. Definitive recommendations for this and other findings await completion of ongoing clinical trials.     

Paradoxical brain embolism with Klippel-Trenaunay syndrome

Cerebrovascular diseases in patients with Klippel-Trenaunay Syndrome (KTS) are uncommon, and the mechanism of stroke has remained elusive. We describe a patient with KTS who experienced a transient ischemic attack (TIA). Contrast-transcranial Doppler with the Valsalva maneuver revealed a right-to-left shunt and contrast-transesophageal echocardiography confirmed patent foramen ovale. Ultrasonography revealed dilated superficial and deep veins in the lower extremities; the D-dimer level was high and indicated hypercoagulability. Therefore, the mechanism of TIA was diagnosed as paradoxical embolism. To the best of our knowledge, this is the first case report of paradoxical embolism in a patient with KTS.     

Aortic atheroma. An unknown source of ischemic stroke

Cerebrovascular mortality represents 25% of all cardiovascular mortality. Defining the pathological mechanism of an episode of ischemic stroke is important for epidemiological, prognostic and overall therapeutic purposes. About 1/4 of ischemic strokes are defined as being of unknown cause. The use of transesophageal echocardiography for studying the aortic arch and thoracic aorta, revealed that aortic atheroma can be considered as an embolic source. Retrospective studies documented a significant prevalence of atheroma >4 mm in the aortic arch in patients with previous stroke (15%); while prospective studies documented an increased risk for cardiovascular events in patients with plaque of =/> 4 mm in thickness at the level of the thoracic aorta compared with controls without these lesions: in particular, the incidence of recurrent stroke is 12%/year, while the incidence of cardiovascular events is 26%. Plaques defined unstable and at risk of embolic event are protrudent, >4 mm in thickness, without calcification and have on their surface mobile thrombus. Embolization from a protrudent atheroma can have a iatrogenic cause, that is cardiac catheterization or placement of an intra-aortic balloon- pump or during cardiopulmonary bypass. The management of the subject with aortic atheroma is not well defined. Encouraging dates with the use of statins are from a recent meta-analysis also anticoagulant treatment versus antiplatelet treatment, reduced incidence of stroke in a significant manner. The surgical therapy of aortic endoarterectomy, has, at this moment, a limited indication, because is not without risk. Transesophageal ecocardiography is a method of choice for the study of the aortic atheroma and it should be done in every patient with stroke by unknown cause.     

Lacunar syndrome associated with paradoxical brain embolism

We report a patient who developed lacunar syndrome due to left upper pons infarction after performing leg exercises associated with paradoxical brain embolism. A 32-year-old man developed right arm weakness and moderate dysarthria following leg exercise. Brain MRI showed a paramedian pontine infarction of the left upper pons, and contrast transesophageal echocardiographic examination indicated that the patent foramen ovale was the embolic source. Simultaneous RI venography examination of the lower limbs identified deep venous thrombosis in the right leg as a paradoxical emboligenic source. We concluded that the presence of lacunar syndrome suggests that this mechanism was responsible for the paradoxical brain embolism.     

Intracoronary air embolism in open heart surgery--an uncommon source of myocardial ischaemia

We report a case of air embolism detected by transesophageal echocardiography in a patient undergoing open heart surgery for acute mitral regurgitation. Intraoperative transesophageal echocardiography revealed an increased brightness of the apical wall and a severely compromised left ventricular myocardium with severe diffuse hypokinesis after removal of the aortic cross clamps and spontaneous resolution in the control echocardiography.     

A case of pregnancy with a history of paradoxical brain embolism

Brain embolisms in younger persons are rare but are often caused by a paradoxical embolism, the embolic entry of a venous thrombus into the systemic circulation through a right-to-left shunt. A 27-year-old pregnant woman presented with hemiplegia that had been treated with an antiplatelet agent since the occurrence of a paradoxical brain embolism via the pulmonary arteriovenous fistula. A tendency of hypercoagulation is generally observed during pregnancy, so a patient with this condition has a strong risk factor for venous thromboembolism during pregnancy and even more so for arterial thromboembolism under the intense strain of labor, which is much stronger than that of the Valsalva maneuver. This case had been controlled well with an antiplatelet agent and an anticoagulant while the levels of coagulation and fibrinolytic factors were monitored and was followed by a successful pregnancy outcome.     

Calcified aortic sinotubular ridge: a source of coronary ostial stenosis or embolism

This report reviews the findings in a calcified lesion involving the ridge at the junction of the sinus and tubular portions of the ascending aorta. The histologic features resemble the alterations in calcified aortic valve and do not exhibit those of atherosclerosis. The 37 cataloged cases are among the more severe and dramatic instances of a lesion more common than the cataloged number would suggest. The involved ridge may be related to any of the sinuses, although that related to the right aortic sinus is most commonly affected. Major complications include coronary ostial stenosis or embolism in an epicardial coronary artery. Ostial stenosis results either from overhanging of an ostium by the aortic lesion or from invasion of the wall of the aorta at the site of the arterial takeoff.     

Potential clinical application of brain natriuretic peptides in acute pulmonary embolism

To the Editor It was a great interest to read the review article on clinicalimplications of B-type natriuretic peptide testing publishedby Cowie et al.¹ It is generally accepted that BNP and NTproBNPcan