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Objectives: To establish the rate of spontaneous closure of atrial septal defects diagnosed before age 3 months, 101 infants (mean age 26 days) with an interatrial shunt confirmed by Doppler echocardiography were followed up for an average of 265 +/- 190 days., Background: Even if interatrial shunts in the newborn are frequently encountered, little is known about their natural history., Methods: Defect diameter on two-dimensional echocardiography and width of color flow jet were measured in the subcostal view. Right and left ventricular diameters and atrial septal curvature were also studied. Kaplan-Meier curves were obtained to predict age of spontaneous closure in relation to initial defect diameter., Results: There was no significant correlation between the diameter of the atrial septal defect and right ventricular/left ventricular ratio or type of septal curvature (vertical or concave toward the left atrium). The classic predominance of girls over boys was observed only for defects > 5 mm. An overall rate of spontaneous closure of 87% was observed. Frequency and timing of closure were inversely correlated to atrial septal defect diameter: closure occurred in 100% (32 of 32) of defects in group 1 (diameter < 3 mm), 87% of defects (39 of 45) in group 2 (diameter 3 to 5 mm), 80% of defects (16 of 20) in group 3 (diameter 5 to 8 mm). Spontaneous closure did not occur in four patients of group 4 (defect > or = 8 mm) during an average follow-up interval of 417 days (range 294 to 597 days)., Conclusions: These results suggest that infants with an atrial septal defect < 3 mm need not be followed up as 100% of these defects will be closed by age 18 months; those with a defect 3 to 5 or 5 to 8 mm should be evaluated by the end of the 12th and the 15th month, respectively, when > 80% of these defects will be closed. An atrial septal defect with a diameter > or = 8 mm may have little chance of closing spontaneously and the possibility of surgical correction should be considered. Defects < 3 mm probably do not constitute a cardiac malformation in light of their natural evolution and gender distribution.

A four-parameter generalization of the Gompertz curve is proposed which passes through the origin with respect to total age and is often more suitable for somatic growth than the three-parameter Gompertz curve. Applied to published cross-sectional data on 44 male white rats, the new curve differs from another four-parameter curve proposed earlier by Jolicoeur and Pirlot (1988) in that it does not involve initial growth delays and it avoids an arbitrary assumption concerning the initial curvature, but it nevertheless yields approximately similar descriptions of chronological growth and complex allometry. The new four-parameter version of the Gompertz curve may be useful in cases where other growth curves do not provide a satisfactory fit.

Sotalol is a beta-blocker with class III antiarrhythmic properties that has recently been used in children for the treatment of supraventricular and ventricular arrhythmias. However, little is known about its electrophysiologic effects on the immature heart. Using intracardiac electrocardiographic recordings and stimulation techniques, 15 canine neonates (8-15 days) and 15 adult mongrel dogs were studied with cumulative doses of sotalol (0.5, 1, 2, and 4 mg/kg plus an additional dose of 8 mg/kg for neonates). Heart rate decreased significantly in the two groups, but more in adult dogs (-43% in adult dogs versus -25% in neonates, p less than 0.05). There was no significant change for QRS duration and His-Purkinje system conduction time interval. QT and atrioventricular nodal conduction time intervals increased in adult dogs and neonates. Sinus node recovery time increased significantly in the two groups, but more in adult dogs. Refractory periods of the atrioventricular (AV) node increased significantly in neonates. Atrial flutter was no longer inducible in 12 of 15 neonates after the 2 mg/kg dose. Atrial effective refractory period increased significantly more in neonates (96%, p less than 0.001) than in adult dogs (58%, p less than 0.001). Ventricular effective refractory periods increased significantly both in neonates (46%) and adult dogs (50%), in a similar way. In conclusion, sotalol has greater electrophysiologic effects on the immature heart at the atrial level when compared to the adult, and similar effects on the refractory period of AV node and ventricle.

Two hundred twenty-four consecutive patients operated on for tetralogy of Fallot were followed from 1 to 28 years (mean 11). Mean age at surgery was 5.3 years (range 1 to 14). Postoperative right ventricular systolic pressure was 60 mm Hg in 19 of 213 patients (9%). Fourteen patients (6%) had ventricular premature complexes on surface electrocardiograms. Seventy-nine patients underwent treadmill exercise tests, and ventricular premature complexes were induced in 17 (22%). Twenty-four-hour ambulatory monitoring in 92 patients demonstrated significant ventricular arrhythmias (greater than or equal to grade 2 of the Lown classification) in 41 (45%). The frequency of ventricular arrhythmias correlated with length of follow-up and duration of cardiopulmonary bypass. No correlation was found with age at surgery, postoperative right ventricular systolic pressure and importance of conduction defects on electrocardiogram. There were no sudden or unexpected deaths during follow-up.

In order to determine which variables are useful and accurate in estimating prognosis in horses with abdominal pain, data were analyzed from 231 horses presented at a veterinary teaching hospital. Using multiple stepwise discriminant analysis in a recursive partition model, we obtained a decision protocol that identified survivors and nonsurvivors. The prevalence of survivors was 61% in this population. The sensitivity, specificity, and positive and negative predictive values of this model were 71, 83, 87 and 65%, respectively. This decision protocol was validated by Jackknife classification and also by evaluation with a referral population of 100 horses in which the prevalence of survivors was 83%. This led to sensitivity, specificity, and positive and negative predictive values of 83, 78, 94 and 50%, respectively.

Isolated partial anomalous pulmonary venous drainage (PAPVD), in contrast to atrial septal defect (ASD), does not cancel out the effects of respiration on blood flow in the right ventricle. The aim of this study was to see whether this difference could contribute to the diagnosis of PAPVD without ASD on M mode echocardiography. The diastolic dimensions of the right ventricle on expiration and inspiration were compared in 4 groups of patients aged 2 to 17 years. Group 1 comprised 6 children with PAPVD without ASD; Group 2: 10 children with PAPVD and ASD; Group 3: 11 children with isolated non-restrictive ASD, and Group 4: 10 normal children. Groups 1 and 4 were comparable with a respiratory variation of RV dimension of 10 to 29%. On the other hand, in Groups 2 and 3 the percentage variation was less than 6%. The finding of isolated RV dilatation with normal respiratory variation of its internal dimension should therefore alert the operator to the possible diagnosis of PAPVD without ASD.

Nine pediatric patients underwent echocardiographic evaluation prior to and after renal transplantation. Prior to transplantation parameters of cardiac contractility such as mean velocity of circumferential fiber shortening, ejection time, ejection fraction and shortening fraction were within the normal ranges for the age group. Post transplantation there was a significant decrease in heart rate and cardiac index. In addition a dramatic increase in hemoglobin levels was observed. The improvement in circulating hemoglobin levels rather than the removal of uremia appears to be the dominant beneficial result in improving cardiovasuclar hemodynamics.

In search of reliable criteria that could help differentiate insignificant atrial septal defects (ASDs) from those with a large shunt, M-mode echocardiograms of three groups of patients were studied retrospectively: group I = 10 normal children (mean age 5.7 years); group II = 10 patients (mean age 7 years) with small ASD in whom the decision was taken not to proceed to surgical closure, based on hemodynamic and angiographic criteria; and group III = 15 patients (mean age 7 years) with an "operable" shunt, who underwent corrective surgery. The results showed that right ventricular end-diastolic dimensions during expiration (RVDDE) were increased in all patients in group III but were normal in only 3 of the 10 patients in group II. A normal septal movement was found in all patients in groups I and II but also in five patients in group III. The variation in right ventricular diastolic dimension with respiration (RVDVR) was always normal in group II. However, in group III all patients but one had a small RVDVR (less than 6%). It was concluded that a normal RVDDE is very specific (100%) but not sensitive (30%), a normal septal movement is very sensitive (100%) and moderately specific (70.6%), and a normal RVDVR is both very sensitive (100%) and specific (94.4%) as a criterion for identification of small ASDs not requiring surgery.

Unlabelled: In order to assess possible changes in myocardial relaxation occurring during the neonatal period, M-mode echocardiograms were recorded serially in 9 normal term infants and in another group of 10 one-month-old infants. The tracings were studied with an M-mode calculator. Although individual variations were greater in the data collected during the first 24 h, no significant difference was found in the indices of diastolic function of the left ventricle during the first 4 days of age. The following changes were observed between data recorded at 4 days and 1 month, respectively: normalized peak rate of left ventricle filling, 4.03 vs. 4.71 cm/s; diastolic peak velocity of early posterior motion of aortic root, 1.89 vs. 5.15 cm/s; peak velocity of left ventricle posterior wall motion in diastole, 3.31 vs. 3.50 cm/s; mitral valve EF slope, 59.05 vs. 84.92 mm/s; left ventricle isometric relaxation time, 43.88 vs. 28.50 ms., In Conclusion: (1) greater individual variations are observed in indices of left ventricle diastolic function during the first day of life, and (2) significant increase in left ventricle compliance occurs during the first month of life. These changes should play a critical role in the clinical course of newborn with cardiopulmonary disease.

Records of two veterinary teaching hospitals from January 1, 1976 to June 1, 1982 were searched for diagnoses of stifle lameness. Forty-two records were found and information was recorded regarding signalment, history and clinical presentation. The following abnormalities were associated with stifle lameness: subchondral bone cyst (18 cases), joint instability (15 cases), degenerative joint disease (12 cases), cranial cruciate ligament injury (9 cases), cytological or bacteriological evidence of sepsis (9 cases), collateral ligament injury (3 cases), femorotibial luxation (2 cases) and intra-articular fracture (2 cases). The duration of lameness presentation ranged from 0.3 to 24 weeks and the mean follow-up period was 20.47 +/- 11.44 months (three animals were lost to follow-up). Animals (n = 15) with subchondral bone cysts as the sole association with lameness presented at an early age (range - 6 to 18 months) and apparently regardless of treatment, had a good prognosis as determined by 75% (three lost to follow-up) returning to their intended function. Cattle (n = 9) with septic arthritis were presented at an age ranging from two months to seven years and only 22.2% returned to function. Cattle (n = 15) with joint instability presented at an age varying from nine months to 13 years also did poorly as only 26.6% returned to function.

Following the study on psychomaintenance of asthma by Kinsman, Dirks, and Jones (1977), we adapted the Battery for Asthma Illness Behavior (BAIB) to children. Thirty-four children aged 9.3 to 15.4 years were tested with this modified BAIB. They were scored simultaneously on a semistructured psychological interview. Three groups emerged out of these data: low-, medium-, and high-panic-fear personalities. Patients were also rated with regard to their pulmonary function and clinical status, including medication prescribed. The high-panic-fear personality was significantly associated with a higher intensity of prescribed medication, in particular corticosteroids. These results were independent of spirometric pulmonary measurements. We conclude that doctors may overreact to the exaggerated distress of high-panic-fear patients. Psychotherapy could be of help for this group.

To determine whether acute alcohol ingestion during pregnancy could affect fetal myocardial function, studies were carried in six chronically catheterized fetal sheep during maternal alcohol infusion. Absolute ethyl alcohol (0.8 ml/kg) was administered to the mother over 10 minutes via the jugular vein. These infusions were repeated every 30 minutes during 3 hours, and peak maternal and fetal blood concentrations close to 200 mg/dl alcohol were reached. Fetal PCO2 decreased from a baseline of 43.15 +/- 3.75 to 36.13 +/- 2.6 torr 1 hour after the start of alcohol infusion (P less than 0.05). Similarly, pH rose from 7.37 +/- 0.027 to 7.44 +/- 0.015 (P less than 0.05). Both values returned to baseline level at the end of alcohol infusion. PO2 remained within physiologic limits. The systolic time intervals of the fetal heart showed a rapid and prolonged modification. The pre-ejection period from 58 +/- 8 to 66 +/- 4 msec (P less than 0.05) during the infusion; this change was related to an increase in the isometric contraction period. The ratio of the pre-ejection period over the ejection time was also significantly increased (P less than 0.01), and remained elevated until the end of the experiment (12 hours). A rise in fetal systolic and diastolic pressures was observed at about 2 hours after the start of the alcohol infusion, and lasted 4 hours. This study suggests that an episode of maternal alcohol intoxication causes rapid depression of fetal myocardial contractility that is maintained several hours after cessation of alcohol ingestion.

Until recently intra-abdominal sepsis following surgery for perforated appendicitis has remained a frequent occurrence. In 1975 Fowler reported an incidence of one intra-abdominal abscess in 36 perforated appendicitis treated with a protocol consisting of saline irrigation at surgery, followed by intraperitoneal administration of cephaloridine q. 6 hours for 48 hours. The same antibiotic was then given i.v. for 72 hours. He concluded that this method was an effective way to minimize post-op intra-abdominal abscess, and that the intraperitoneal route was more effective, for this purpose, than systemic administration. More recently, with better knowledge of the role of anaerobes, improved results have also been obtained by adding clindamycin or metronidazole to the antibiotic regimen. A prospective study based on two groups of patients randomly assigned to two protocols was undertaken. The study group consisted of 45 children operated for perforated appendicitis with abscess or generalized peritonitis. These patients were treated with Fowler's protocol. Because it is less nephrotoxic and is active against the same organisms, cefazolin was used instead of cephaloridine. The control group consisted of 43 patients, also operated for perforated appendicitis, treated with saline irrigation at surgery, with either i.v. gentamycin or tobramycin and clindamycin or metronidazole for an average of 7.8 +/- 3.1 days. Both groups were fairly well matched in terms of age, sex, severity of disease, and bacterial flora. They showed an identical 6% post-op intra-abdominal sepsis rate. Days before afebrile, days under gastric suction, complications and average hospital stay were comparable in both groups. The wound infection rate was 20% in the study group and 9% in the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Thirty lactating Holstein cows were in two groups in a study of effects of vitamin B12 injections on milk fat synthesis. All cows were fed a normal fiber diet for the first 28 days after calving and then adjusted gradually to a low fiber diet over the next 28 days. After adjustment to the low fiber diet, in a single reversal trail, cows received either 150 mg of vitamin B12 in the form of hydroxocobalamin intramuscularly every 7 days for 21 days or no treatment for 21 days. Daily milk yield (kg), percent milk fat, and milk fat yield (g) for the normal fiber, low fiber adjustment, low fiber control, and low fiber plus vitamin B12 treatments were 29.6, 3.59, 1192; 31.5, 2.85, 840; 28.0, 2.58, 715; and 28.8, 2.65, 760. Injections of vitamin B12 did not correct the milk fat depression associated with the low fiber diets. In addition, there was no consistent relationship between blood B12 and milk fat production. Milk fat production was highly correlated with molar percent acetate in the rumen .63 and with blood acetate concentration .74.

Twelve infants, average age 5, 4 weeks (range 3 to 8 weeks) with congenital hypothyroidism were studied. In addition to routine evaluation including plasma T3, T4 and TSH estimation and the establishment of a clinical index of hypothyroidism on electrocardiogram and an echocardiogram were performed. The following variables were analysed: heart rate, QRS axis in the frontal plane, PR interval in Lead II, corrected QT interval in V5, amplitude of the P waves in Lead II, R waves in V3R, V1, V5 and V6; S waves in V1, V2 and V4 and T wave in V6. The ventricular activation time in V5 and QRS duration in V3R, V1 and V6 were also measured. The presence of pericardial effusion, left ventricular posterior wall and septal thickness, and left ventricular internal diastolic and systolic dimensions were determined by echocardiography. The following conclusions were drawn: 1. The ECG of hypothyroidism in the neonatal period is characterised by the low amplitude of the left ventricular potentials while increased conduction times were much less evident; 2. Only the sum of R + S in V2, the amplitude of the T wave in V6 and increase in QRS duration in V3R were influenced by severity of hypothyroidism; 3. Left ventricular microvoltage is not due to pericardial effusion which was absent in all our cases.

Echocardiographic assessment of cardiac function was made on 24 children with chronic renal failure of varying etiology and severity. In 20 patients without evidence of cardiac failure, parameters of left ventricular performance as represented by PEP/LVET and mean velocity of circumferential fiber shortening were within normal limits in the majority of patients. In addition, ejection fraction and shortening fraction were, in most children, within the 95% confidence limits for their age. In 4 patients who presented with congestive heart failure, marked left ventricular dilatation was noted in association with decreased shortening and ejection fractions and depressed mean velocity of circumferential fiber shortening. Also the PEP/LVET in these patients suggested the presence of a uremic cardiomyopathic condition. These studies, in addition to our own studies on children who have undergone fistula construction, hemodialysis, and transplantation, suggest that cardiac performance, in the majority of pediatric patients with end-stage renal disease, is well maintained and that the major factor involved in reducing exercise tolerance is the presence of uremic anemia. Only a minority of patients may develop severe uremic heart disease.

In cardiac allografts acute rejection produces deleterious effects on blood flow adjustments. In order to differentiate the role of rejection over that of denervation cardiac denervated and cardiac transplanted dogs were compared. A canine model of orthotopic cardiac transplantation was utilized. Electronic devices were implanted for chronic hemodynamic studies. Regional myocardial blood flow distribution was assessed by radioactive microspheres (15 micron in diameter). Studies were carried out when animals had fully recovered (two to three days postoperatively), then in the 'early rejection' stage (five to six days post transplant) and in the 'severe rejection' stage (24 h before death). No significant difference in hemodynamic data or blood flow values were observed between groups in the recovery stage. In the denervated group, adequate cardiac function and myocardial blood perfusion was maintained throughout the study. In the transplanted group, significant loss of function was observed at the severe rejection stage. This was combined with significant decrement in blood flow to all areas of the myocardium. No selective area of underperfusion nor an early reduction in total blood flow could be observed. This study indicates that within cardiac rejection there is a parallel impairment in function and transmural myocardial blood flow which is unrelated to denervation or interruption of lymphatics.

The cardiac hemodynamic effects of patent Brescia Cimino fistulas were assessed using non-invasive techniques in 10 pediatric patients who had undergone successful renal cadaveric transplantation. All had hemoglobin levels above 11 g/dl and had serum creatinine values of less than 1.5 mg/dl. Studies were done prior to and after temporary fistula occlusion to assess the effect of fistula patency on parameters of cardiac function. Values obtained prior to fistula occlusion were compared to those obtained in a normal control population. It was noted that though fistula patency did significantly alter cardiac function, changes were such that fistula patency could be safely maintained. It was also noted that the difference in cardiac index prior to and after occlusion provided a good assessment of fistula flow.

The authors studied the time of conception of 280 fetuses and liveborns with anencephaly or spina bifida seen in a French Canadian population during a period of six years. There is an evident seasonal variation in the conception of NTD fetuses. Using a wave statistical model applied to data recorded over a six year period the authors have rejected the "no variation between the six two-month intervals" hypothesis at a P less than or equal to 0.005 level. It is postulated that, in any vitamin intake or environmental program to prevent NTD in families at risk, one must take into account the annual and seasonal variations, ethnic groups identity and the date of conception in the choice of control mothers.

Since heart rate influences the values of many hemodynamic parameters, the authors have examined the effect of heart rate variations noted after cardiac transplantation on the hemodynamic criteria of rejection. They have undertaken serial studies at intrinsic rate and at a paced atrial rate of 150 beats/min in 11 resting homotransplanted dogs. The authors analysed cardiac index, stroke volume, peak velocity, acceleration, stroke power and stroke work. Results at intrinsic and paced atrial rates were compared during each of three phases of postoperative evolution: phase II (2 to 3 days after transplantation), phase III (4 to 5 days) and phase IV (6 to 7 days postoperatively). Phase II, being the period of maximum recovery, served as a baseline for comparing the cardiac parameters in phases III (the initial phase of rejection) and phase IV (24 hours before death). The authors found that the patterns of change were similar at intrinsic and paced atrial rates and concluded that heart rate variation does not significantly influence the hemodynamic criteria of rejection.

This preliminary study evaluated phenoxymethyl penicillin (Penicillin V) as an alternative to parenteral administration of penicillin in horses. Penicillin V was administered orally to five horses at two different doses and plasma levels of the drug were determined at timed intervals. The results were evaluated by regression analysis. Following the administration of penicillin V at a dose of 66,000 IU/kg or 110,000 IU/kg, the mean peak plasma levels obtained were 1.55 micrograms/mL and 2.34 micrograms/mL respectively. A plasma level two to four times above the minimal inhibitory concentration level of Streptococcus equi and Streptococcus zooepidemicus was maintained for 325 minutes at 66,000 IU/kg and 349 minutes at 110,000 IU/kg. Penicillin V given orally was thus shown to be an acceptable alternative to parenteral administration of penicillin in the horse.