Medical Memoranda BRITISH3 ventricular rate of 68. The P wave was of normal shape; the QRS complex was of normal duration (0.08 second); the S-T segment was slightly depressed in leads I, aVL, and V6 ;' and the T waves were flattened or inverted in I and aVL. The pattern indicated heart-block and suggested anterolateral ischaemia and left ventricular strain. The patient died within six days of admission from cerebral haemorrhage and heart failure.Post-mortem Findings.-Brain: There was a recent haemorrhage into the white matter in the right parieto-occipital region, while an old apoplectic cyst was found in the left putamen. The larger arteries were atherosclerotic. Heart: This weighed 360 g. The left ventricle was moderately dilated and hypertrophied, the parietal and valvular endocardium was smooth, and the myocardium was brownish yellow. No macroscopical changes were found around the outlet of the coronary sinus or around the pars membranacea septi. The coronary arteries were moderately atherosclerotic. Aorta : This was atheromatous, with some ulcerated plaques in the abdominal part. The remaining viscera were congested and the lungs were oedematous.Microscopical Findings.-A single block comprising the base of the interatrial septum and the upper three-quarters of the interventricular septum was fixed in formalin and embedded in paraffin. Serial sections were cut 50 ju apart and stained with haematoxylin and eosin, azan, or orcein. The region adjacent to the central fibrous body, which is normally rich in fatty and soft connective tissue, was found to be diffusely and coarsely fibrotic (Special Plate, Fig. 1).The atrioventricular node and its connexions with the right atrium showed sclerosis and severe atrophy. Within the predominant fibrous strands and interlaced with elastic fibrils there were several channels, scattered or in groups, lined by thick layers of swollen endothelial cells often occluding the lumen. A few channels were slightly dilated and lined by a single layer of endothelial cells which sometimes protruded into the lumen (Special Plate, Fig. 2), and some of these were empty while others contained acidophilic debris. The sections, however, did not have a cystic pattern. Perilymphatic infiltration with round cells was often seen (Special Plate, Figs. 3, 4, and 5). A small amount of calcium was deposited among the fibrous strands. The area of abnormal histology involved a few square millimetres on each of the sections from the base of the interatrial septum to the upper border of the bundle of His, but it was never very well demarcated. Distally the right bundle branch was normal but the roots of the left were partially damaged. Sections from the walls of both ventricles showed no areas of myocarditis.
DISCUSSIONFive cases of heart-block ascribed to lymphangioendothelioma of the heart have been reported (Armstrong and Monckeberg, 1911;Lloyd, 1929;Perry and Rogers, 1934; Rezek, 1938; Mahaim, 1945). The diagnosis in these cases was made on the necropsy findings of whitish nodules and of cysts, an...