Maria Serratto

The conduction system in Pompe's disease

SummaryWe report our findings in the microscopic examination of the conduction system in four infants with glycogen storage disease, one of whom had adequate electrophysiologic studies. The electrophysiologic studies in the latter case showed P-A and A-H intervals at the lower limits of normal, but the H-V interval was just above the normal mean. This suggests that the rapid conduction was not localized in the anatomic counterpart of the H-V interval. The short P-R interval in the ECG may be related to the enlargement of cells, which may in turn be related to increased glycogen content. The relationship of glycogen per se to the speed of conduction is unknown.We found that the summit of the ventricular septum bulged, probably because of the generally increased cell size, and that the topography of the atrioventricular conducting system was different from normal. This is possibly related both to an increase in the cell sizes of the specialized conducting tissue itself and to deforming effects of this bulging summit of the ventricular septum. New microscopic details of the components of the conducting system are described in these cases.

Operative Repair for Tricuspid Atresia

Twelve patients with tricuspid atresia underwent physiological operative repair. The criteria for their selection for operation included normal pulmonary vascular resistance and normal left atrial and left ventricular end-diastolic pressures. Four patients died (30% mortality). The 8 surviving patients developed pleural effusion, ascites, and hepatomegaly, which markedly improved in the subsequent weeks. Five of the 8 survivors underwent cardiac catheterization. The arterial oxygen saturation in these patients averaged 82% preoperatively, 89% immediately postoperatively, and 94% or better six months later. All had improved subjectively and developed increased exercise tolerance.

Effect of Glucagon on Renal Functions in the Dog.

Summary HGF increases GFR and RPF consistently but transiently in the dog, does not affect FF, at times decreases TmG. Tolerance does not develop during long term daily HGF administration nor does this regimen increase the basal renal functions.

Cardiac index in ambulatory patients estimated by precordial dilution curves

Abstract 1. 1. Four hundred and twenty-nine radiocardiograms were obtained in 240 ambulatory patients with and without heart disease by means of wide angle external counting over the precordium after the injection of radioactive iodinated human serum albumin into an antecubital vein. Cardiac index was calculated from the radiocardiogram and the blood volume. Only seven patients were encountered in whom a tracing adequate for calculation of cardiac index was not obtained. 2. 2. A mean cardiac index of 3.51 L. per minute per square meter surface area with a standard deviation of 0.97 was derived from forty-eight persons without known cardiac or vascular disease. Cardiac indices were slightly but significantly lower when derived from radiocardiograms taken twenty minutes after the initial tests. By contrast, cardiac indices did not differ significantly when calculated from tracings made weeks to months apart in patients with stable cardiovascular systems. 3. 3. A significant decrease in cardiac index was observed in patients with all types of heart disease who had congestive heart failure, whether overt or controlled. 4. 4. In the absence of congestive heart failure, mean cardiac index was increased in patients with borderline hypertension, normal in those with systolic hypertension, and frequently reduced in those with sustained diastolic hypertension, especially when evidence of myocardial involvement also was present. 5. 5. Cardiac index was usually normal in patients with coronary artery disease in the absence of congestive heart failure. Occasional reduction was seen in patients with old myocardial infarctions. 6. 6. A probably significant decrease of cardiac index as measured by the external counting technic was observed in patients with valvular heart disease without congestive heart failure. Also, cardiac index in congestive heart failure due to valvular heart disease was lower than that due to other types of heart disease. Valvular insufficiency apparently leads to erroneously low values of cardiac index estimated by the external counting technic. 7. 7. Classification of radiocardiograms according to qualitative features showed some correlation with cardiovascular status. Prominent fluctuations on the downslope were recognized most often in radiocardiograms of patients with valvular insufficiency. The appearance of the radiocardiogram maintained a constancy over considerable periods of time in the absence of marked change in cardiovascular status.

Special DepartmentLetter To The EditorObstructing ventricular septal defect in double outlet right ventricle

Abstract Three cases of double outlet right ventricle with evidence of interventricular obstruction are presented. In 2, the diagnosis was established by hemodynamic and cineangiocardiographic studies. The arterial oxygen saturation was normal, indicating a preferential flow of blood from the left ventricle into the aorta. The systolic pressure in the right ventricle and aorta was equal, and a significant gradient between the left ventricle and aorta was found. Gineangiocardiography showed a high aorta originating from the right ventricle and demonstrated that a small ventricular septal defect was the only outlet of the left ventricle. In the third case, postmortem examination revealed that the ventricular septal defect was very small. A combined subaortic and subpulmonary conus was present with a prominent subaortic component. The portion of the subpulmonary conus related to the ventricular septal defect was markedly distorted. This arrangement appeared to be responsible for the small size of the ventricular septal defect. It is suggested that the presence of an obstructive ventricular septal defect in double outlet right ventricle constitutes a developmental complex with characteristic clinical, hemodynamic and angiocardiographic features.