Interrupted aortic arch in infancy

Data from 30 infants with interrupted aortic arch in the New England Regional Infant Cardiac Program, 1968 to 1974, were reviewed. All patients had major associated cardiac abnormalities: approximately one third had ventricular septal defect with patent ductus arteriosus, one third had complex ventricular septal defect with left ventricular outflow obstruction, and one third had complex intracardiac lesions incompatible with survival. Twenty-one of the patients had either palliative or reconstructive surgery, with a hospital mortality rate of 76%. Nine patients did not have surgery; eight of them died at a median age of four days. One-stage primary repair of interrupted aortic arch including the associated cardiac defects, using deep hypothermia and circulatory arrest, is proposed as the current method of treatment in such infants.

Intraoperative recording of the His bundle electrogram in man. An assessment of its precision

To estimate the effect of distance between the electrode and the signal source on the amplitude of the His bundle electrogram (HBE) recorded during open heart surgery, a specially designed probe, containing six pairs of closely spaced (1 mm) electrodes was placed on the endocardial surface of the right atrium such that each electrode pair was parallel to the course of the His bundle. The amplitude of the HBE recorded through electrodes closest to the His bundle ranged from 0.76 to 2.44 mV, at 1mm from 0.38 to 1.13 mV, at 2mm from 0.27 to 0.86 mV, and at 3 mm from 0.2 to 0.44 mV. Maximal amplitude of HBE decreased by 57% at 1mm, 73% at 2 mm, and 82% at 3mm. The percent decrease was initially rapid, then declined more slowly at distances greater than 1 mm, resembling in form data obtained previously in animal studies by different techniques. Since the maximum HBE was greater than 1.0 mV in nine of 11 patients, and equal to or greater than 1.0 mV in only two of 11 patients at 1 mm, and less than 1.0 mV in all patients 2.0 mm from the maximal HBE, the anatomic location of the His bundle can be estimated from HBE amplitude. Intracardiac electrograms, recorded through closely spaced bipolar electrodes during open heart surgery, afford clinically useful precision in locating the specialized conduction tissue of the heart.

Left ventricular function in tricuspid atresia. Angiographic analysis in 28 patients

Thirty-one left ventricular (LV) biplane angiograms were performed in 28 patients with tricuspid atresia. Measurements of left ventricular end-diastolic volume (LVEDV) and left ventricular end-systolic volume were obtained by the modified Simpson's rule and systolic ejection fraction (EF) calculated. Left ventricular volumes and ejection fractions were also obtained in 19 control patients with no significant heart disease. The patients with tricuspid atresia were classified according to the appearance of the pulmonary vascularity on initial radiologic examination: Group A, decreased pulmonary vascularity; Group B, increased pulmonary vascularity. In the 13 group A infants who were unoperated, LVEDV was increased and EF mildly diminished. In the group B patients LVEDV was increased and EF normal. In the 12 group A patients with surgical shunts LVEDV was elevated. The five group A patients with long-standing systemic artery to pulmonary artery anastomoses (greater than 10 years) showed the largest LVEDV and the poorest EF. The angiographic data indicate that patients with tricuspid atresia experience significant LV dysfunction as a consequence of longstanding LV volume overload. The early detection of LV dysfunction may be an indication for a right ventricular bypass procedure in these patients.

Repair of tetralogy of Fallot after catheterization-induced complete heart block

The case of a four-year-old boy with tetralogy of Fallot who developed complete heart block during cardiac catheterization and subsequently underwent surgical repair in the presence of heart block is presented. Return to normal sinus rhythm occurred on the 11th postoperative day, and the manner in which increased atrioventricular conduction appeared was documented with the use of a continuous Holter monitor. Placement of a temporary transvenous pacemaker, systemic heparinization in the preoperative period, and the insertion of a permanent epicardial wire during surgery were performed.

Tricuspid atresia: clinical course in 101 patients

The clinical profile and course of 101 patients with tricuspid atresia seen at the Children's Hospital Medical Center, Boston, were reviewed; the electrocardiograms, hemodynamic data, associated anomalies, complications of the malformation and surgical results were outlined and a definition of anatomic types and radiologic groups formed in order to facilitate therapeutic decisions. Overall survival to 15 years of age was approximately 50 percent. Tricuspid atresia type 1 (normally related great arteries), group A (decreased pulmonary vascularity) was the most frequent category (54 percent); without surgery, these patients had only a 10 percent chance of survival beyond the 1st year of life. Surgical intervention improved chance of survival to 15 years of age to 50 percent. Overall surgical mortality was 23 percent. The Waterston shunt is the procedure of choice in symptomatic small infants with diminished pulmonary flow (group A). Type II patients with increased pulmonary blood flow (group B) would benefit from a pulmonary arterial band. In contrast, patients with group B, type I atresia would rarely need a pulmonary arterial band. Patients with spontaneously changing hemodynamics (group C) usually require a shunt later in life than those in group A, with more favorable operative results. Our experience indicates the continued need of early surgical palliation. New surgical approaches, such as the right atrial-pulmonary arterial anastomosis, may result in a more prolonged survival.

The orthopaedic training programme in indonesia

I was fortunate to visit Indonesia in association with the Orthopaedic Training Programme, firstly whilst on holiday in October 1970 and later as a volunteer in an advisory capacity in March 1971 at the request of the Indonesians involved in the Orthopaedic Training Programme.

Estimation of faecal fat excretion using cuprous thiocyanate as a continuous marker

A method for the estimation of faecal fat excretion using cuprous thiocyanate as a continuous marker is described. Results obtained from a single stool sample are in close agreement with those from a three-day collection using this technique. The method is simpler and more accurate than collections done without a marker.

Effect of ethanol on magnesium excretion

The effect of ethanol on magnesium excretion was studied in three normal subjects. It was found that the ingestion of 2 ml ethanol/kg body weight produced a marked immediate increase in urinary magnesium excretion, but there was no significant effect on overall magnesium balance when this amount was taken daily for eight days.

CONCERNING THE RELATIVE RESPONSE TO BLOOD GAINS AND BLOOD LOSSES; AND HABITUATION TO AN EXCESS OF BLOOD PIGMENT

The effects of very gradually increasing or diminishing the amount of circulating hemoglobin have been studied in rabbits. Contrary to expectation it was found that when the pigment was increased by the injection of a small quantity of compatible blood every day during some weeks the erythropoietic tissue did not lessen its activities. The hemoglobin percentage mounted gradually yet considerably when even as little as 1/100 of the amount of blood initially possessed by the animal was injected each day; and the figure it finally attained must in some instances at least have been expressive of a superabundance. To this superabundance the animal itself evidently contributed through its persisting erythropoietic activity. The results were very different when rabbits were bled daily to the same small amount that was injected into their fellows. The marrow became abnormally active, and this activity continued undiminished throughout the long period of the bleedings. The organism is evidently far more susceptible to blood losses than to blood gains, a fact which is scarcely surprising when one considers that throughout its differentiation as a going concern it has had to cope with exigencies of the first sort only. Rabbits in which the hemoglobin is very gradually increased by the injection of strange blood become so accustomed to the abundance of pigment that even a slight falling off causes the erythropoietic tissue to become abnormally active to maintain the new status quo. Good reasons exist for referring the habituation thus manifested to readjustments in the functioning of the physiological mechanisms which mediate between oxygen demand and erythropoietic response. Too little recognition has been given to the rôle of these mechanisms in such relation. No evidence was obtained of any effective readjustment to protect the erythropoietic tissue from the stimulus of daily small blood losses.