We prospectively studied 14 patients with the carcinoid syndrome to determine if twodimensional echocardiography could detect the nature and extent of valvular abnormalities. Eight of the 14 patients had definite abnormalities of the right-sided cardiac valves. The tricuspid valve had a characteristic appearance, similar to previously described pathologic findings. The leaflets appeared diffusely thickened, shortened and stiff without evidence of commissural fusion. Saline contrast studies demonstrated tricuspid regurgitation, which corresponded to the severity of the tricuspid valve involvement. The pulmonary valve could only be adequately assessed in seven of 14 patients, and morphologic abnormalities similar to those in the tricuspid valve were found. Follow-up studies have shown progression of cardiac disease in six of eight patients. We conclude that two-dimensional echocardiography can detect the characteristic cardiac abnormalities in the carcinoid syndrome and may be a useful tool for following their progression.

A spontaneous tear of the ascending aorta, with or without medial dissection, can cause sudden death from hemorrhage due to aortic rupture. Two representative cases are described. Review of the clinical history and pathological changes showed that the terminal event was delayed allowing healing and reactive changes to occur in the aortic wall. A pathologist confronted with a fatal case of aortic rupture should be aware that death is not always immediate. Recognition of this has medicolegal importance, particularly if medical management is questioned because of a missed clinical diagnosis.

the tip of the catheter, are 30 cm long, have an outer diameter of 0.16 + 0.005 cm, and are translucent at the proximal end.I believe that the use of multilumen umbilical venous catheters will greatly improve care for critically ill neonates requiring central venous access.

The presence of muscle disarray in hypertrophic cardiomyopathy (HC), although well established, has only been semiquantitatively assessed. A quantitative method that uses polarized light microscopy is described. Hematoxylin and eosin-stained sections of ventricular septa from six HC patients and six normal hearts were examined. Cell orientations were measured in five regions from each section using a polarizing microscope with a rotating stage. Histograms of cell orientation angles were plotted and the mean and angular deviation of each sample were calculated. In normal hearts, cells were predominantly aligned parallel to each other. Orientation distributions were sharply peaked, with angular deviations ranging from 4 to 13 degrees. For HC, the sharp peak was lacking and angular deviations varied from 7 to 37 degrees; some distributions were bimodal. Areas in HC septa that appeared normal by gross inspection had abnormal orientation distributions. Polarized light microscopy provides an improved method of detecting and quantifying cellular disorganization in HC.

Stroke models in larger animals such as the cat, dog and monkey are becoming increasingly more expensive and less readily available. However, the rat is an excellent model for focal cerebral ischemia. Rats are readily available, inexpensive and their neuroanatomy and brain function have been studied extensively. Increases in plasma catecholamines and myocardial damage have been observed in clinical stroke. We examined autonomic and myocardial changes in two rat stroke models. In one model only the middle cerebral artery was occluded (MCAO) while the other model involved occlusion of both the MCA and the common carotid artery (MCAO/CCAO). Arterial blood pressure and heart rate were monitored continuously in 25 male rats (326-430 g) that underwent one of the following procedures: (1) MCAO only; (2) MCAO/CCAO; (3) CCAO only; and (4) sham occlusions (SHAM). Arterial blood samples (0.5 ml) for radioenzymatic assay of norepinephrine (NE) and epinephrine (E) were taken twice before the occlusions and at 90 and 180 min after the occlusions. The animals were perfused at the end of the experiment and the heart removed and examined histologically. Tetrazolium salts were reacted with oxidative enzymes to delineate the region of inadequate perfusion. The mean blood pressure and pulse pressure of the SHAM, MCAO/CCAO and CCAO groups significantly declined from initial values (from an average of 78 to 53 mm Hg) during the course of the experiment. However, the mean blood pressure and pulse pressure of the MCAO rats did not change during the experiment, so that the final mean blood pressure and pulse pressure were significantly higher than in the other 3 groups. The levels of both NE and E increased significantly (NE, 1443 +/- 285.9 to 4095 +/- 929 pg/ml; E, 2402 +/- 623 to 3741 +/- 1166 pg/ml) following occlusion in the MCAO group only while the other 3 groups did not change. Four of 6 hearts in the MCAO group were abnormal, showing evidence of subendocardial hemorrhage, ischemic damage or subendocardial congestion. MCAO also resulted in a consistent region of the brain with inadequate perfusion including the insular cortex. These autonomic and myocardial changes appear to mimic some of the changes seen clinically in stroke patients and provide the first acute stroke model for studying autonomic dysfunction in the rat.

Strut fracture, with embolization of the disc occluder, caused the death of a 64-year-old man who had a Beall model 105 heart valve prosthesis in the mitral position for 13 years. Scanning electron microscopy of the fractured surface revealed evidence of a fatigue failure mechanism in the metal wire. The case is unique in that strut fractures affecting this prosthesis had only been observed previously in the range of 141 to 342 days after implantation. Morphological changes in this valve prompted reexamination of three other model 105 prostheses that had been recovered from the mitral area at necropsy or surgery 9 to 10 years after insertion in 1972 or 1973. All had been kept in dry storage. The three prostheses and the valve described above showed previously unrecognized cracks in the pyrolytic carbon coating of the struts, which form the cage that limits occluder movement. The defects were located at or near the base of struts, where they entered the sewing ring and were bent to pass into the strut supporting ring. We believe that the cracks in the carbon coating precede total strut fracture and postulate that they are needed for the metal wire to be subject to a fatigue failure mechanism.

Focal cerebral ischemia in humans increases the incidence of cardiac arrhythmias, and serum cardiac enzyme and plasma norepinephrine levels. In addition, systemic administration of catecholamines causes myocardial damage. This suggests that cerebral ischemia may cause myocardial damage as a consequence of elevated plasma norepinephrine levels. Therefore, experiments were done in 23 chloralosed, paralyzed and artificially ventilated cats to investigate the effects of occluding (n = 17) or sham-occluding (n = 6) the left middle cerebral artery on the myocardium and on circulating levels of plasma catecholamines. After occlusion of the middle cerebral artery for 12-22 hr, 41% (7/17) of the hearts had either acute myocardial necrosis (3/7), focal hemorrhage (3/7), or both (1/7). In animals with acute myocardial damage the levels of plasma norepinephrine and epinephrine were significantly increased compared to pre- middle cerebral artery occlusion values (+46 +/- 18% and +142 +/- 45%, respectively). As well, in cats with acute myocardial damage, changes from initial levels of plasma norepinephrine and epinephrine were significantly increased over those of experimental cats without acute myocardial damage. In animals which did not have acute myocardial damage (10/17) the circulating plasma levels of catecholamines were not significantly different from pre-occlusion values. Similarly, sham occlusion did not alter plasma catecholamine levels. These data demonstrate that a percentage of animals subjected to middle cerebral artery occlusion have myocardial damage and an increase in plasma concentration of norepinephrine and epinephrine. This suggests that a rise in plasma catecholamine levels, due to increased sympathetic activity after middle cerebral artery occlusion, may cause myocardial damage.

In the past decade most studies of coronary arterial aneurysms have been clinical; few have focused on morphology and etiopathogenesis. The subjects of the present autopsy study were 52 patients, 5 months to 80 years of age, with coronary arterial aneurysms. Patients were divided into two groups: 38 with atherosclerotic coronary aneurysms and 14 with aneurysms secondary to inflammation. Of the 38 patients with atherosclerotic aneurysms, 20 (53 per cent) had histories of ischemic heart disease; the aneurysms were in the right coronary artery in 18 (47 per cent), the left coronary artery in 13 (35 per cent), and in the right and left coronary arteries in seven (18 per cent). Of the four major coronary arteries, the average number of severely narrowed arteries (reduction of more than 75 per cent) in cross-sectional luminal area) was 1.8/patient; aortic aneurysms were present in eight of these patients (24 per cent). Of the 14 patients with coronary aneurysms secondary to inflammation, four had histories of ischemic heart disease; 10 had histories of an influenza-like syndrome. Isolated left coronary arterial aneurysms were seen in six of these patients (43 per cent), while eight (51 per cent) had multiple right and left coronary arterial aneurysms. The average number of severely narrowed coronary arteries in this group was 1.5/patient, and only one patient had an aortic aneurysm. Therefore, patients with atherosclerotic aneurysms are more often symptomatic; they have increased heart weights and equal numbers of coronary arterial aneurysms in the right and left vessels, and the majority (89 per cent) have single aneurysms with thrombi in the lumen. Patients with coronary arterial aneurysms secondary to inflammation are younger; the majority of these patients have a prodromal influenza-like syndrome, a low incidence of ischemic heart disease, and multiple coronary arterial aneurysms.

Ten Lillehei-Kaster heart valve prostheses, in situ for up to 10 years and recovered at surgery or necropsy, were examined by light and scanning electron microscopy. All showed metal wear on the luminal aspect of their struts. The volume of wear related to the duration a prosthesis had been in situ. The worn metal showed distinct, transverse surface corrugations, which became more obvious with time. Aortic prostheses wore more and faster than mitral ones. One strut usually showed more wear than the other, a change likely due to specific manufacturing methods. It is believed that the pattern of wear is caused by a velocity-controlled stick-slip abrasive wear process, resulting from an interaction between the edge of the moving pyrolytic carbon disc, the struts' titanium surface, and the protein coat covering that surface. None of the patients had prosthesis dysfunction attributable to metal wear. Disc escape seems unlikely considering the degree of wear observed after 10 years. Furthermore, the surface corrugations did not appear to cause disc sticking or other problems. However, clinicians might consider monitoring patients who have borne these prostheses for greater than 10 years.

A patient with cerebral strokes had a cardiac tumour excised. Histologically, it was an infarcted myxoma with features of a Gamna body. Findings are compared with other cardiac Gamna bodies reported in the literature. Most probably represent unusual degenerative changes in a myxoma.

Autopsy studies of three premature siblings who died soon after birth with the neonatal myotonic dystrophy syndrome revealed pulmonary hypoplasia and congenital pleural effusions. Neither of these findings has been described previously in this condition. New ultrastructural findings include focal diaphragmatic myofiber degeneration and necrosis, which were attributed to over-stretching of the fetal diaphragm. In addition, abnormally small stores of free and intravesicular glycogen were observed in skeletal muscle fibers. The morphometric features of control fetal and neonatal skeletal muscle were recorded for comparison with muscle fiber measurements in the three infants. Fiber diameters in the latter were much smaller than expected for body weights. The morphologic and morphometric findings support the concept that fetal muscle maturation is severely retarded in this syndrome.

The ductus arteriosus was examined in 103 fetuses and infants to define the normal structure, development, and morphologic features of the functional and anatomic phases of ductal closure. New contributions include ultrastructural observations and the light microscopic definition of the junctional regions of the ductus with the pulmonary artery and aorta. Observations relating to ductal closure include hyperemia of the ductal vasa vasorum, the presence of longitudinal muscle bands in the inner media, necrosis of the inner ductal wall, and organization of intraluminal thrombi. We found that a ductus arteriosus that fails to close normally is liable to show morphologic lesions, including intimal fibrinous deposits, medial hemorrhages, and dissecting aneurysms. The findings were used comparatively to investigate whether prostaglandin E1 infusion, given to maintain ductal patency in 7 infants with ductus dependent congenital heart disease, was associated with specific morphologic features. We could not delineate specific changes attributable to its use.

Cardiomyopathy develops in some individuals who have a susceptibility to malignant hyperthermia. We studied right ventricular endomyocardial biopsy specimens from nine patients defined as having this disorder because of positive caffeine contracture tests on skeletal muscle biopsy specimens. Three patients had clinical evidence of cardiomyopathy and six did not. Light microscopy showed cytoplasmic contraction bands, perinuclear clearing, and a mild to moderate variation in myocyte and nuclear size. Ultrastructurally cytoplasmic contraction bands were associated with cardiac villi, myofiberlysis, and myofibrillolysis. These changes and occasional breaks in the sarcolemma were regarded as artefacts of the biopsy procedure. Megamitochondriosis with accompanying degenerative changes in the mitochondria were also seen and probably indicate increased cell metabolism; vacuolation of the cytoplasm was regarded as an "aging" phenomenon. Thus, the biopsy specimens were abnormal, but the changes were artefactual or nonspecific and were not unique to this group of patients. Biopsy did not provide a morphological explanation for abnormal cardiac function.

The pathology of a case of idiopathic calcification affecting the ascending aorta in a young woman is presented. A varying width of media throughout the aorta and extending into its proximal branches was devoid of cell nuclei (medial necrosis) although elastic lamellae persisted. Plaques of calcium, found in the acellular media, were confined to the ascending aorta. No inflammatory or reparative reaction was seen in the vessel wall. Electron microscopically, the calcium seemed to have an affinity for elastic tissue elements of all sizes and the mode of deposition appeared to be by ‘avenues’ of the microfibrillar component Possible pathogenetic mechanisms are discussed.