Contrast echoes detected during percutaneous mitral balloon commissurotomy with Inoue balloons and their relation to cerebral microembolic signals

The aim of this study was to find out the mechanism of genesis of contrast echoes detected with echocardiography during percutaneous mitral balloon commissurotomy (PMBC) procedures with Inoue balloons and to assess their association with cerebral microembolic signals with transcranial Doppler examinations. Ten Inoue balloons (Toray Instruments) were used in 10 patients (mean age 36 +/- 10 years). In all patients transesophageal echocardiographies with a multiplane 5 MHz probe were performed immediately before and during the PMBC procedure. None of the patients had left atrial thrombus during the PMBC. All of the balloons were inflated within the left atriums and left ventricles and were tested in saline to see whether there was a visible air leak after the PMBC procedures. Transcranial Doppler examinations were done with 2 MHz probes from the middle cerebral artery. Contrast echoes were detected in all patients during inflation and/or deflation, independent of the intracardiac sites. After a few cardiac cycles there was a very intense shower of microembolic signals detected with the transcranial Doppler examination, which persisted for all inflations and/or deflations. All balloons yielded visible air leaks from the two small holes at the waist of the balloons in saline. There were a few contrast echoes recorded in some of the patients during the exchange of equipment, and one patient had a transient neurologic and coronary ischemic event following the introduction of the stretcher tube of the Inoue balloon. Intracardiac contrast echoes and transcranial microembolic signals during the PMBC procedure were detected in all PMBC procedures and were due to air that was entrapped between the two latex layers of the Inoue balloons and air introduced from outside during the exchange of the equipment.     

Transient paradoxical embolism. Importance of early ultrasonography diagnosis

The paradoxical embolism or the crossing of an embolism through a permeable foramen ovale is considered to be a rare mechanism of cerebral embolism although its real frequency is unknown. Reports demonstrating the embolism during its crossing through cardiac cavities are scarce. Two cases of moving paradoxical embolism are presented. In the first, an infarction of the superior branch of the left middle cerebral artery was produced during the course of deep vein thrombosis and pulmonary thromboembolism with transesophageal echocardiography demonstrating the crossing of the embolism through the foramen ovale. Surgery performed 12 days later did not discover the auricular thrombus. In the second case, a mass was discovered in the right auricle with a permeable foramen ovale during the course of a left middle cerebral artery infarction and a large auricular thrombus was demonstrated in surgery. The diagnostic usefulness of early transsesophageal echocardiography in the diagnosis of moving paradoxal embolism is discussed.     

A gloverin-like antibacterial protein is synthesized in Helicoverpa armigera following bacterial challenge

The elucidation of patterns of cranial skeletal maturation and growth in fossil hominids is possible not only through dental studies but also by mapping different aspects of ossification in both extant African apes and humans. However, knowledge of normal skeletal development in large samples of extant great apes is flimsy. To remedy this situation, this paper offers an extensive survey and thorough discussion of the ossification of the posterior border of the sphenoid greater wing. Indeed, this area provides much information about basicranial skeletal maturation. We investigate three variants: the absence of the foramen spinosum and the position of both the foramen spinosum and the foramen ovale in relation to the sphenosquamosal suture. Providing original data about humans and 1,425 extant great ape skulls and using a sample of 64 fossil hominids, this study aimed to test whether different ossification patterns occurred during the course of human evolution. The incidence of three derived morphologies located on the posterior border of the sphenoid greater wing increases during human evolution at different geological periods. The evolutionary polarity of these three derived morphologies is assessed by outgroup comparison and ontogenetic methods. During human evolution, there is a clear trend for the foramen spinosum to be present and wholly located on the posterior area of the sphenoid greater wing. Moreover, in all the great ape species and in Australopithecus afarensis, the sphenosquamosal suture may split the foramen ovale. Inversely, the foramen ovale always lies wholly within the sphenoid greater wing in Australopithecus africanus, robust australopithecines, early Homo, H. erectus (and/or H. ergaster), and Homo sapiens. From ontogenetic studies in humans, we conclude that, during human evolution, the ossification of the posterior area of the sphenoid greater wing progressively surrounded the middle meningeal artery (passing through the foramen spinosum) and the small meningeal artery (passing through the foramen ovale).     

Patent foramen ovale is an important predictor of adverse outcome in patients with major pulmonary embolism

BACKGROUND: Right-to-left shunt through a patent foramen ovale is frequently diagnosed by contrast echocardiography and can be particularly prominent in the presence of elevated pressures in the right side of the heart. Its prognostic significance in patients with pulmonary thromboembolism, however, is unknown. METHODS AND RESULTS: The present prospective study included 139 consecutive patients with major pulmonary embolism diagnosed on the basis of clinical, echocardiographic, and cardiac catheterization criteria. All patients underwent contrast echocardiography at presentation. The end points of the study were overall mortality and complicated clinical course during the hospital stay defined as death, cerebral or peripheral arterial thromboembolism, major bleeding, or need for endotracheal intubation or cardiopulmonary resuscitation. Patent foramen ovale was diagnosed in 48 patients (35%). These patients had a death rate of 33% as opposed to 14% in patients with a negative echo-contrast examination (P=.015). Logistic regression analysis demonstrated that the only independent predictors of mortality in the study population were a patent foramen ovale (odds ratio [OR], 11.4; P<.001) and arterial hypotension at presentation (OR, 26.3; P<.001). Patients with a patent foramen ovale also had a significantly higher incidence of ischemic stroke (13% versus 2.2%; P=.02) and peripheral arterial embolism (15 versus 0%; P<.001). Overall, the risk of a complicated in-hospital course was 5.2 times higher in this patient group (P<.001). CONCLUSIONS: In patients with major pulmonary embolism, echocardiographic detection of a patent foramen ovale signifies a particularly high risk of death and arterial thromboembolic complications.     

Intracardiac thrombus trapped in a patent foramen ovale

We describe a case of impending paradoxical embolism due to a thrombus trapped in a patent foramen ovale in a 22-year-old woman. Transthoracic and transesophageal echocardiography detected the thrombus. She was operated on and discharged asymptomatic.     

Intracranial microembolic signals during radiofrequency ablation of accessory pathways

Intracranial microembolic signals, probably caused by gaseous emboli, are readily detectable in patients undergoing radiofrequency ablation in the left side of the heart only. Clinical value of the detected signals could not be equivocably assessed, because only 2 of the patients who were examined (both emboli positive) had transient neurologic symptoms.     

Vascular distribution of paradoxical emboli by transcranial Doppler

BACKGROUND AND PURPOSE: Paradoxical embolism through a patent foramen ovale is a contributory mechanism to stroke and may be diagnosed by contrast echocardiography. The intracranial distribution of these emboli has not been previously reported. METHODS: We used transcranial Doppler combined with agitated saline contrast injection to determine whether there was a preferential distribution of the contrast into the anterior or posterior intracranial circulation of patients with an acute stroke or transient ischemic attack. RESULTS: Forty-nine patients were studied--27 men and 22 women, with a mean age of 62.7 +/- 13.3 years (range, 29 to 85 years). Microcavitations were detected in the proximal right middle cerebral artery in 12 of 49 patients (24%). A patent foramen ovale was confirmed in all cases by simultaneous transesophageal echocardiography. Of the 12 patients, microcavitations were also detected in the proximal basilar artery in nine (75%). CONCLUSIONS: While paradoxical embolism appears to occur more frequently in the anterior circulation, the high rate of detection of microcavitations in the basilar artery suggests that paradoxical embolism to the posterior intracranial circulation may be more frequent than generally believed.     

Intracardiac right-to-left shunting and the risk of stroke during bone marrow infusion

We describe a patient who developed a paradoxical embolus to the brain during infusion of bone marrow. She had a patent foramen ovale through which right-to-left shunting led to multiple cerebral emboli. This complication can be prevented by positioning the tip of the infusion catheter in the main pulmonary artery and reducing the volume of marrow product infused.     

Pulmonary embolism and impending paradoxical embolism: a role for transesophageal echocardiography?

Thrombolysis is advocated as the treatment of choice for hemodynamically important pulmonary embolism. This paper reports the case of a patient with subacute massive pulmonary embolism in which thrombolysis was not considered appropriate because transesophageal echocardiography demonstrated a patent foramen ovale and impending paradoxical embolism.     

Combined valve replacement and coronary bypass grafting in osteogenesis imperfecta

Open cardiac procedures in osteogenesis imperfecta have been associated with a high mortality rate. A patient with osteogenesis imperfecta underwent successful aortic valve replacement and coronary artery bypass grafting along with closure of a patent foramen ovale in preparation for a planned hip replacement.     

Postpneumonectomy interatrial right-to-left shunt: successful percutaneous treatment

This report describes the case of a 67-year-old man in whom atrial right-to-left shunt developed after a right pneumonectomy, leading to dyspnea with severe arterial desaturation. Transcatheter occlusion of the patent foramen ovale was successfully performed using a buttoned device. Review of literature and mechanisms of these atrial right-to-left shunts are discussed.     

Combined lytic and heart surgical therapy of in open foramen ovale incarcerated giant thrombus with pulmonary and cerebral embolization

A case of phlebothrombosis with recurrent pulmonary and cerebral embolism is presented which occurred in a 42 year old patient two weeks after treatment of a traumatic crural fracture despite of prophylaxis with low molecular heparin. By means of transthoracic echocardiography a large intracardiac thrombus was detected, entrapped in an patent foramen ovale (PFO) and prolapsing through both atrioventricular valves into both ventricles. This was found after systemic thrombolysis with rtPA had been performed because of fulminant pulmonary embolism. Subsequently the intracardiac thrombus was surgically removed and the PFO closed. The importance of an PFO for paradoxical embolism is discussed as well as the various therapeutical paths to treat an "embolus-in-transit" (cardiac surgery, thrombolytic therapy or anti-coagulation).     

Comparison of hemodynamic cerebral ischemia and microembolic signals detected during carotid endarterectomy and carotid angioplasty

BACKGROUND AND PURPOSE: There has been concern about carotid percutaneous transluminal angioplasty (PTA) carrying a greater risk of cerebral ischemia than carotid endarterectomy. We set out to compare cerebral hemodynamics and microembolization during carotid PTA and CEA. METHODS: We used transcranial Doppler to monitor the middle cerebral artery of 28 patients undergoing carotid PTA (n = 14) or carotid endarterectomy (CEA) with a shunt (n = 14). Each period during which the internal carotid artery was occluded by PTA balloon or by clamp when the shunt was not in place was timed. Individual periods were summated to give a total occlusion time. Ischemic time was defined as the period for which mean middle cerebral artery velocity fell to a third or less of baseline. Microembolic signals were counted during each procedure. RESULTS: CEA resulted in significantly longer individual and total occlusion time than PTA (mean individual occlusion time, seconds), CEA, 168 +/- 51; PTA, 20 +/- 7; P < .001; mean total occlusion time; CEA, 337 +/- 70; PTA, 26 +/- 10; P < .001. Ischemic time was also significantly longer during CEA than during PTA (CEA, 165 +/- 40; PTA, 17 +/- 5; P = .001). There were significantly more microembolic signals during PTA than during CEA (mean number of microembolic signals during CEA, 52 +/- 64; during PTA, 202 +/- 119; P = .001). There was no correlation between any of the parameters measured and periprocedural stroke, which occurred in one patient in each group. CONCLUSION: PTA results in less hemodynamic ischemia but more cerebral microembolism than CEA. In this small series, however, it is not possible to comment on the relations between ischemic time, microembolism, and stroke.     

Oesophageal phlebectasis in an infant with pulmonary venous obstruction owing to a congenital heart defect

Clinical findings and postmortem examination of a newborn infant are reported. Prominent features were a complex congenital heart defect ("pre-mature closure of foramen ovale", with mitral and aortic atresia), causing severe obstruction to pulmonary venous return, pulmonary lymphangiectasis and oesophageal phlebectasis. The occurrence of oesophageal phlebectasis in infants with congenital pulmonary venous obstruction is reviewed and the pathogenesis discussed.     

A complication of pacemaker lead extraction: paradoxical embolism of a lead fragment in a leg artery

Extraction of three chronically implanted pacemaker leads was performed via the implant vein in a 71-year-old man. One of the leads broke in the subclavian scar tissue. The lead fragment migrated into the left peroneotibial trunk artery. Transesophageal echocardiography showed patent foramen ovale associated with right-to-left atrial shunt. This complication of lead extraction is discussed along with the role of echocardiography prior to lead removal.     

Computer-assisted detection of cerebral embolism using a multi-range principle

Since its introduction into the clinical setting at the beginning of the 'eighties, transcranial Doppler sonography (TCD) has gained increasing acceptance as a non-invasive neuromonitoring technique. The ability of TCD to detect embolic particles within the cerebral blood vessels has been the subject of intensive investigation in recent years. In the present paper, a new method for the detection of emboli (multirange principle), intra-operatively during a neurosurgical intervention in a 35-year-old patient with a tumour in the posterior fossa and an open foramen ovale, is described for the first time. The method opens up new possibilities for the intra-operative management and the rapid assessment and diagnosis of paradoxical cerebral embolism.     

Diagnosis and therapy of a fluttering thrombus in the open foramen ovale

The finding of an extremely mobile thrombus in a patent foramen ovale (i.e., transit thrombus) without arterial embolism is rare. In our case-report diagnosis was made by routine-echocardiography. Clinically nonapparent deep vein thrombosis was documented by phleography and was thought to be the origin of the embolus. After implantation of a caval filter device cardiac surgery was performed and the embolus was removed without complications.     

Successful innominate thromboembolectomy of a paradoxic embolus

A 54 year-old man had symptoms of acute right hemispheric cerebral ischemia. He was initially considered for participation in a trial of early thrombolysis in stroke, but an innominate artery embolus was found with no apparent arterial source. The embolus was removed by means of a combined brachial and carotid bifurcation approach to protect the cerebral vasculature from embolic fragmentation during extraction. Further investigation revealed deep venous thrombosis, evidence of pulmonary emboli, and a patent foramen ovale, supporting a diagnosis of paradoxic embolus. Additional treatment included anticoagulation and placement of an inferior vena caval filter. The unusual condition of paradoxic embolus is reviewed, and the management of this patient is discussed.     

D-transposition in situs inversus, atrial septal defect, open foramen ovale and tricuspid valve insufficiency

This paper reports on a rare case of a so-called corrected d-transposition of the great vessels of a 62-year old woman with situs inversus. In addition the patient had a VSD, a patent foramen ovale, and a tricuspid-valve insufficiency. The topography of the ventricular cavities, the great vessels and the coronary arteries is described in detail. There is pointed to the surgical treatment of additional abnormalities to improve the prognosis.     

Chiari's network: normal anatomic variant or risk factor for arterial embolic events?

OBJECTIVES: This study was performed to assess the prevalence of Chiari's network in patients undergoing transesophageal echocardiography and to determine whether this anomaly is associated with other cardiac lesions or is characterized by typical clinical findings. BACKGROUND: Chiari's network is a congenital remnant of the right valve of the sinus venosus. It has been found in 1.3% to 4% of autopsy studies and is believed to be of little clinical consequence. METHODS: Video recordings of 1,436 consecutive adult patients evaluated by transesophageal echocardiography over a 30-month period were reviewed for the presence of Chiari's network. Echocardiographic contrast studies had been performed in all patients with Chiari's network and were compared with those of 160 consecutive patients without a Chiari net, serving as a control group. RESULTS: Chiari's network was present in 29 of 1,436 patients (prevalence 2%). A frequently associated finding was a patent foramen ovale in 24 (83%) of the 29 patients with Chiari's network versus 44 (28%) of 160 control patients (p < 0.001). Intense right-to-left shunting occurred significantly more often in patients with Chiari's network than in control patients (16 [55%] of 29 patients vs. 19 [12%] of 160 control patients, p < 0.001). Another frequent association was an atrial septal aneurysm in 7 (24%) of 29 patients. The indication for transesophageal echocardiography was a suspected cardiac source of arterial embolism in 24 (83%) of 29 patients with a Chiari net, 13 of whom (54%) had recurrent embolic events. Chiari's network was significantly more common in patients with unexplained arterial embolism than in patients evaluated for other indications (24 [4.6%] of 522 patients vs. 5 [0.5%] of 914 patients, p < 0.001). Potential causes for arterial embolism were present in 9 of the 24 patients with a Chiari net and embolic events (atrial septal aneurysm in 7, cerebrovascular lesion in 2). In 15 (62%) of 24 patients only a patent foramen ovale could be identified. Three patients had deep venous thrombosis and pulmonary embolism at the time of arterial embolism; none had a thrombus detected within the network. CONCLUSIONS: In patients undergoing transesophageal echocardiography, the prevalence of Chiari's network was 2%, which is consistent with autopsy studies. By maintaining an embryonic right atrial flow pattern into adult life and directing the blood from the inferior vena cava preferentially toward the interatrial septum, Chiari's network may favor persistence of a patent foramen ovale and formation of an atrial septal aneurysm and facilitate paradoxic embolism.