Cutaneous manifestation of atrial myxoma

A left atrial myxoma may present in a manner that diverts attention from its cardiac origin. This case report documents a cutaneous clinical presentation that initially was thought to represent a peripheral vasculitis or connective tissue disease. Biopsy specimens revealed a peripheral arterial myxomatous embolus in the skin, and echocardiogram results were diagnostic for atrial myxoma. Embolic manifestations may occur in up to 40% of cases. We hope that description of this patient will alert others to suspect this tumor in unexplained or peculiar forms of vasculitis and to consider an echocardiogram as part of the diagnostic workup.

Intraglomerular embolization by tubular cells

Intraglomerular embolization by tubular epithelial cell is a rare artefact found in needle biopsy specimens. The authors have observed this phenomenon in five out of 300 renal biopsy cases. Tubular epithelial cells, were present in the glomerular capillaries (in two cases) or in the capillaries and within the glomerular urinary space (in three cases).

The pathology of cholesterol embolism arising as a complication of intra-aortic catheterization

Cholesterol embolism is an unusual but serious complication of intra-arterial procedures such as arteriography and angioplasty. The pathological findings in four cases confirm that this syndrome is due to disseminated micro-emboli composed mainly of cholesterol crystals and that these originate from atheromatous plaques in the aorta which may be traumatized by the catheter used in the intra-arterial procedure. However, angiography is not the sole precipitating cause of this syndrome but is an exacerbating event in a pre-existing process.

Cartilage embolism of spinal cord

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Direct in vivo observations of embolic events in the microcirculation distal to a small-vessel anastomosis

This study was done to determine whether microemboli are produced by an arterial anastomosis. Direct in vivo observations were made in an isolated microcirculatory bed lying directly downstream from a newly made anastomosis. The tissue used was the isolated rat cremaster muscle, a new experimental model. The vessel anastomosed was the external iliac artery. Following anastomosis, microemboli were clearly observed in eight of eight animals during the first 30 minutes after clamp release. Embolic events were sometimes of impressive magnitude and in one case were associated with cessation of blood flow throughout the preparation. No microemboli were observed in eight of eight animals subjected only to dissection of the cremaster, nor were any observed in eight of eight animals in which the isolated cremaster was subjected only to 2 hours of clamp ischemia. These findings may be significant in explaining perturbations to blood flow following free-tissue transfer and instances of partial tissue necrosis following apparently successful arterial repair. These findings also identify an important factor (microemboli) to be considered in research on reperfusion injury.

Myocardial stiffness and reparative fibrosis following coronary embolisation in the rat

The structural nature of fibrillar collagen involved in the replacement fibrosis which accompanies discrete areas of cell necrosis remains uncertain, as does its influence on the diastolic and systolic stiffness of the intact myocardium. This study, using 15 micron diameter microsphere embolisation of the rat myocardium, was undertaken to address these issues. Collagen volume fraction (trichrome), fibrillar collagens (picrosirius-polarisation technique), and the stress-strain relations of the intact myocardium (isolated hearts) were determined 30 d after the infusion of microspheres into the left ventricle. Significant differences from controls included: (a) the presence of hypertension secondary to renovascular embolisation; (b) a greater volume fraction of collagen that included not only a meshwork of short, taut appearing, thick and thin collagen fibres, interposed between muscle in areas of cell loss, but also a perivascular fibrosis involving intramyocardial coronary arteries; (c) elevated active stiffness, and (d) a more exponential diastolic stress-strain relation with increased stiffness at strains of 5% or more. These findings suggest that the replacement fibrosis accompanying myocyte necrosis has distinguishing morphological features involving fibrillar collagen and which because of its structure, alignment, and location relative to muscle leads to enhanced myocardial stiffness, including a more exponential rise in the diastolic stress-strain relation. The perivascular accumulation of collagen suggests that additional factors other than microsphere induced necrosis were responsible for this reactive fibrosis.

Embolic stroke from a carotid arterial source in the rat: pathology and clinical implications

We developed a new animal model of stroke which resembles human stroke more closely than existing models. We described the pathology produced in the brain following platelet embolism, previously described only in the retina. The common carotid artery of the rat was irradiated for 6.5 minutes with an argon laser at 514.5 nm after intravenous injection of a photosensitizing agent, rose bengal. A retinal embolus was seen in 1 rat 5 minutes after irradiation. A nonocclusive platelet thrombus was present in the carotid artery 50 minutes after irradiation, with almost all the platelet thrombus being cleared 24 hours later. Acute (1 to 10 days) changes in the brain included 44 small infarcts in 12/13 rats, cortical arterioles occluded with platelets and thickening of small vessels in normotensive rats. Chronic (4 to 12 weeks) changes included lacunes in the brains of normotensive rats and intimal proliferation of smooth muscle in the carotid artery. This is the 1st animal model of (1) stroke with emboli produced in vivo rather than injected into the carotid, (2) intimal proliferation of smooth muscle without invasion of the vessel, and (3) lacunes. This model provides results important to the laboratory study of stroke.

Embolic and metastatic cardiac myxoma

This paper presents a case of a cardiac myxoma with cutaneous emboli. The diagnosis of a cardiac lesion was anticipated after the histologic examination of a skin lesion. The first clue to the existence of a cardiac myxoma was a distinctive intravascular lesion of a dermal vessel. The clinical and pathologic features of cardiac myxoma are discussed. In addition, new evidence regarding the nature of a previously reported case of metastasizing cardiac myxoma is also presented.

[Cardiac thrombosis and embolism in patients having died of chronic Chagas cardiopathy]

The authors studied the files of 111 patients (mean age 47.5 years) with chronic Chagas' disease and severe heart failure who had died between 1978 and 1984; they were 72 men and 39 women. Eighty-one patients (73%) had cardiac thrombosis, 65 times (53%) in right chambers and 56 times (46%) in left ones. Sixty-seven patients (60%) had thromboembolic episodes, 41 (65%) to the lungs, 23 (38%) to other organs (target organs: the kidneys in 21 cases, spleen in four, brain in two, abdominal aorta in one, mesenteric artery in one and iliac artery in one). Right chamber thrombosis occurred 65 times, 35 (53%) with pulmonary thromboembolism. Left chamber thrombosis occurred 56 times, 24 (42%) with systemic thromboembolism. A total of 41 patients had pulmonary thromboembolism, only six (14%) without right chamber thrombosis; of 26 patients with systemic thromboembolism, only two (7%) did not have left chamber thrombosis. The authors concluded that the incidence of thrombosis and thromboembolism was high in the group studied, and that there was a relationship between chamber thrombosis and systemic or pulmonary thromboembolism.

A case of aortic intimal sarcoma manifested with acutely occurring hypertension and aortic occlusion

Primary tumor of the aorta is extremely rare. An instance of aortic intimal sarcoma, namely fibromyxosarcoma, which extended from the beginning of the descending aorta to 7 cm above the abdominal bifurcation, with clinical evidence of acutely occurring hypertension, arterial embolism of the lower extremities, renal infarction, and aortic occlusion in a 50-year-old male is reported. The tumor was limited to the intima and composed of spindle-shaped tumor cells with abundant myxoid extracellular matrices. The tumor cells were negative for Factor VIII, Desmin, or Myoglobin, but were positive for Vimentin or Factor XIIIa in immunoperoxidase studies. An electron microscopic examination revealed a large amount of rough endoplasmic reticulum in the cytoplasm. Parenchymal metastases were observed in both the lungs and thoracic vertebrae. A review of literature on the clinical and pathological aspects of the tumor was made.

Embolic anterior ischemic optic neuropathy

The presumed cause of anterior ischemic optic neuropathy is atherosclerotic vascular changes. Small-vessel occlusive vascular disease most likely causes occlusion of one or more posterior ciliary arteries, compromising blood flow to the optic nerve head and choroid. We present the case of a 59-year-old black man with cholesterol emboli within the retinal vasculature combined with a clinical picture of anterior ischemic optic neuropathy and choroidal nonperfusion demonstrated by i.v. fluorescein angiography. We believe this is evidence that, in a rare case, embolic phenomena may be the cause of anterior ischemic optic neuropathy.

Bone marrow embolism following cryosurgery of bone: an experimental study

Cryosurgery is commonly used in medicine for treatment of benign and malignant lesions. We had clinical and experimental data indicating that cryosurgery of intact bone could cause bone marrow intravasation and embolism, i.e., particles of bone marrow entering extraosseous veins and occluding pulmonary vasculature. This study was designed to investigate the pathogenesis of bone marrow intravasation and embolism after cryosurgery. Three hypotheses on the pathogenesis of bone marrow intravasation were tested using a model of cryosurgical continuity lesion in rats and rabbits. Influence of physical and circulatory factors were excluded supporting a mechanical-biological hypothesis; the intravasation of bone marrow after cryosurgery of bone is caused by an increased intramedullary pressure. The increased intramedullary pressure is due to edema in the medullary cavity caused by cryosurgical damage to cell membranes. It is demonstrated that the bone marrow intravasates can embolize to the lungs causing respiratory insufficiency. This can be a serious complication following cryosurgery of intact bone. Prophylactic decompression of the medullary cavity can possibly prevent the rise in intramedullary pressure and thus intravasation and embolisation of bone marrow after cryosurgery of intact bone.

An autopsy case of cholesterol embolism following percutaneous transluminal coronary angioplasty and aortography

A 67-year-old woman with a 6-year history of angina pectoris underwent percutaneous transluminal coronary angioplasty. Just after manipulation of the guiding catheter during a second attempt at angioplasty and aortography, the patient developed intestinal obstruction with peritonitis. Laparotomy was performed, and surgical specimens taken during surgery revealed necrosis and perforation of the small intestine. Microscopical examination proved that this was the result of multiple fresh cholesterol emboli in the arteries. Postoperatively, renal failure and sepsis developed, and the patient died 13 days after surgery. Autopsy revealed multiple cholesterol emboli in arteries of the intestine, spleen, pancreas, liver and kidneys. This case demonstrates that cholesterol embolism can be a serious complication of percutaneous transluminal coronary angioplasty.

Atheroablation with the Kensey catheter: a pathologic study

The mode of action of the Kensey catheter, a new atheroablation device, was investigated. Fresh above-the-knee amputated legs were used for recanalization of the superficial femoral artery. The variables used were identical to those of clinical trials, including a rotational speed of 50,000 rpm and an injection rate of 40 mL/min. The debris produced by the catheter was studied cytologically, and the arterial segments were examined histologically. The particle size in the debris ranged from 1 to 2,000 microns. The softer plaques produced a fine fibrin dust background with long strips of intima ranging from 10 to 2,000 microns. Complicated calcified plaques produced larger background material (10-120 microns) but smaller strips of intima (50-800 microns). Dissections and perforations occurred. Some of the debris produced by the atheroablation process was used to embolize a canine heart and kidney. Small focal infarctions were found in the heart, and large and multiple infarcts were seen in the kidney. In clinical studies the debris appears to be tolerated in the lower extremities. Its safety in the kidney and heart are questioned.

[Intraglomerular tubular epithelial emboli]

A rare morphological phenomenon is described. In the glomeruli of a kidney needle-biopsy sample, intracapillary cell-clusters were found showing the characteristics of proximal tubular epithelium. The phenomenon is thought to be an artifact of needle-biopsy.

Coronary arterial embolism due to valvular debris after percutaneous valvuloplasty of calcific mitral stenosis

A 74-year-old woman with refractory congestive heart failure due to long-standing calcific mitral stenosis who refused surgical intervention was treated with percutaneous balloon valvuloplasty. After an uneventful procedure, hemodynamic results were satisfactory with an increase in the mitral valve area from 0.4 to 1.1 cm2. Five hours after the procedure, the patient had a bout of vomiting followed by pulmonary aspiration. Electrocardiography, and in the further course, creatine kinase MB elevation, showed anterior myocardial infarction. Necropsy disclosed embolic material in the mid left anterior descending artery which unequivocally consisted of valvular material. This case demonstrates embolism of valvular debris as a life-threatening, procedure-related complication of percutaneous valvuloplasty of calcific mitral stenosis.

Embolism of massive hepatic tissue in inferior vena cava and right atrium after closed liver injury

Embolism from liver tissue in a major vessel in coincidence with a severe injury to the liver is a rare phenomenon. We report a case of a 4-year-old boy who was involved in a traffic accident and died shortly after the accident. An autopsy revealed that an intrahepatic inferior vena caval injury was accompanied by a severe closed injury to the liver; the crushed liver fragment was driven through the lacerated wall into the inferior vena cava and almost completely occluded its lumen. The crushed liver flap further extended over into the right atrial cavity. Careful microscopic examination of the lungs showed no emboli of hepatic tissue.