Rhabdomyosarcoma arising within congenital pulmonary cysts: report of three cases.

Over the past 9 months, three cases of primary pulmonary rhabdomyosarcoma have been treated at British Columbia Children's Hospital. Two patients (aged 24 and 37 months) presented with spontaneous pneumothoraces and had cystic changes in the affected lung on chest radiograph. The third patient (aged 42 months) was evaluated for chronic cough, fever, and failure to thrive. Chest x-ray showed a large mass in the left lower lobe as well as mediastinal adenopathy. All three of these lesions originated within congenital lung cysts, one a peripheral bronchogenic cyst and the others cystic adenomatoid malformations. This report suggests that there is a significant risk for the development of rhabdomyosarcoma within malformed pulmonary tissue.

Myocardial oedema and ventricular function after cardioplegia with added mannitol.

Myocardial oedema may contribute to the impaired myocardial performance which commonly follows open heart surgery with cardioplegia-induced cardiac arrest. The rate of oedema formation during crystalloid cardioplegia and the relation of this to changes in ventricular compliance and ventricular function following reperfusion were studied using an isolated rabbit heart preparation. Myocardial tissue water content increased during cardioplegic arrest and the water content prior to reperfusion demonstrated an inverse correlation with ventricular function after reperfusion. In further studies the effect of adding mannitol to a standard crystalloid cardioplegic solution was investigated. The preparations were divided into two groups: nine were administered a standard cardioplegic solution (Plegisol*) (control group) and a further eight were administered the same solution mixed with mannitol to adjust the osmotic pressure to 360 mOsmol.L-3 (mannitol group). The mannitol group demonstrated less increase in RV water content and superior LV dP/dtmax following reperfusion. It is concluded that mannitol enhances protection of the myocardium during cardioplegic cardiac arrest.

The effect of desmopressin acetate (DDAVP) on postoperative blood loss after cardiac operations in children.

We investigated the effect of an intraoperative desmopressin acetate infusion on blood loss after cardiac operation in 60 children, by using a prospective, randomized, double-blind trial. Thirty patients received a desmopressin dose of 0.3 microgram/kg intravenously over 15 minutes at the conclusion of cardiac bypass, and 30 received a saline placebo. The two groups were comparable with respect to age, sex, cardiac lesion, presence of cyanosis, and prevalence of Down's syndrome. Results showed no significant difference in postoperative blood loss between the two groups (30.5 +/- 37.9 ml/kg in the placebo group versus 40.0 +/- 33.1 ml/kg in the desmopressin group). Postoperative bleeding time, total urine output, postinfusion hemodynamics, and postoperative coagulation studies did not differ significantly between the two groups. We conclude that postbypass desmopressin infusion does not reduce blood loss in children undergoing cardiac operations.

Influence of echocardiography in pre-operative cardiac catheterization in congenital heart disease.

The influence of echocardiography on pre-operative cardiac catheterization was assessed in a retrospective analysis comparing two 12-month periods. Of 245 operations in 1983, 200 (82%) had pre-operative cardiac catheterization when two-dimensional echocardiography only was used in the pre-operative assessment compared to 162 of 238 (68%) operations in July 1985-June 1986 when pulsed Doppler echocardiography also was used (P less than 0.001). Significant reductions in pre-operative cardiac catheterization were present in both open (87/87 vs 89/102, P less than 0.001) and closed (113/158 vs 73/136, P less than 0.005) heart procedures. The group with the most significant reduction in pre-operative cardiac catheterization before open heart surgery were children with atrial septal defects; of the closed heart surgical groups, the greatest reductions were in patent ductus arteriosus, coarctation of the aorta and tetralogy of Fallot. Echocardiogram diagnostic errors occurred in 22/245 (9%) in 1983 compared to 9/238 (4%) in 1985/86 (P less than 0.05). Echocardiography has resulted in a significant reduction in pre-operative cardiac catheterization and has become more accurate in diagnosis.

Left ventricular systolic and diastolic function after two-stage anatomic correction of transposition of the great arteries.

Anatomic repair of transposition of the great arteries (TGA) has been developed because of concerns about right ventricular function after atrial repair by the Mustard or the Senning technique. This study assessed left ventricular systolic and diastolic function in three patients after two-stage anatomic repair. Two patients had a ventricular septal defect (one with coarctation), and the third patient had right ventricular dysfunction precluding atrial repair. All had pulmonary artery banding. The mean ages at the time of repair and catheterization were 2.75 and 4.9 years, respectively. The control group included 10 patients with insignificant or no cardiac disease. At cardiac catheterization the group with TGA had a higher mean end-diastolic volume index (110.9 +/- 4.74 ml/m2) compared to normal subjects (79.1 +/- 14.55; p less than 0.001), mean end-systolic volume index (37.3 +/- 3.69 vs 22.7 +/- 4.42; p less than 0.001), mass index (101.0 +/- 16.9 vs 68.2 +/- 12.34; p = 0.038), and stroke volume index (73.6 +/- 3.52 vs 56.5 +/- 12.1; p = 0.0027). The ejection fractions, end-diastolic and peak systolic pressures, and stresses were not different. There was no difference in the relationship between the mean rate-corrected velocity of circumferential fiber shortening and end-systolic stress for the group with TGA, but myocardial stiffness was markedly elevated (29.5 +/- 1.84 vs 10.8 +/- 2.20; p less than 0.001). Thus, this study found abnormalities of left ventricular size after two-stage anatomic repair of TGA in this group of patients with TGA.(ABSTRACT TRUNCATED AT 250 WORDS)

Total anomalous pulmonary venous return with left heart hypoplasia.

A term baby had a total anomalous pulmonary venous return to the inferior vena cava. The infant underwent complete repair, but died 30 hours after operation. The postmortem examination revealed severe endocardial fibroelastosis. This uncommon association is discussed.

Pulmonary artery banding: results and current indications in pediatric cardiac surgery.

The results of pulmonary artery banding in 144 patients seen from 1971 to 1984 were reviewed. Age ranged from 1 week to 4 years (median, 8 weeks) and weight, from 1.1 to 16 kg (median, 4 kg). The patients were divided into three major groups: Group 1, defects without mixing disorders (ventricular septal defect, double-outlet right ventricle [DORV], atrioventricular septal defect); Group 2, defects with mixing disorders (transposition of the great arteries, DORV, single ventricle, tricuspid atresia); and Group 3, miscellaneous (mitral atresia, left ventricular hypoplasia, truncus complex). The diagnostic group influenced survival (p = 0.0035). In Group 1, 88.8% survived, but only 64.9% survived in Groups 2 and 3 combined. The presence of patent ductus arteriosus or coarctation of the aorta had no effect on survival (p = 0.61 and p = 0.7, respectively). The clinical condition at thirty days after pulmonary artery banding was good in 35.1% and fair in 46.9% of the patients. When the data were divided into the three periods 1971 through 1974, 1975 through 1979, and 1980 through 1984, which included 28, 49, and 67 patients, respectively, a significant improvement in survival was observed from the early (64.3%) to the late period (92.5%) (p = 0.0009). Patients weighing less than 4 kg had a significantly lower survival in the period 1971 through 1974 (37.5% versus 91.67%). No significant difference in survival was detected in the late period, 1980 to 1984 (90% versus 94.6%), between patients weighing less than and those weighing more than 4 kg. Pulmonary artery banding is clinically satisfactory in small infants and children with complex anomalies.

Left ventricular systolic and diastolic function after total correction of tetralogy of Fallot.

Left ventricular (LV) systolic and diastolic function was assessed in 12 patients after total correction of tetralogy of Fallot (age range 5 to 18 years, mean 10) and compared with 10 control patients. Only 1 patient had a shunt before total correction that was performed at a mean age of 3.5 years, (range 0.3 to 8). At cardiac catheterization the following indexed LV parameters were measured: end-diastolic and end-systolic volumes, wall mass, ejection fraction, stroke volume and end-diastolic and end-systolic pressures and stresses. The rate-corrected mean velocity of fiber shortening was calculated. LV diastolic operant chamber stiffness and myocardial stiffness were calculated from simultaneous diastolic pressures and volumes in mid- and late diastole using monoexponential formulas. The 2 groups were compared by unpaired t tests. The tetralogy group had higher mean end-diastolic (93 vs 74 ml/m2), end-systolic (29 vs 19 ml/m2) and stroke (64 vs 55 ml/m2) volumes than controls. Rate-corrected mean velocity of fiber shortening was lower in the tetralogy group (1.07 vs 1.24). Myocardial stiffness was higher in the tetralogy group (16 vs 11). Other indexes were not significantly different. Thus, LV function after total correction of tetralogy of Fallot may be abnormal with larger than normal LV size, decreased contractile function and increased myocardial stiffness.

Experience with polytetrafluoroethylene grafts in children with cyanotic congenital heart disease.

Survival and event-free rates of 47 polytetrafluoroethylene (PTFE) (Gore-Tex) shunts for severe cyanotic congenital heart defects were studied in 42 children from April, 1981, to March, 1983. Retrospective actuarial analysis was conducted over the 27 months of the study in 3-month intervals of the follow-up. The estimated actuarial patient survival at two years was 86% with an estimated actuarial event-free rate of 57.2%. The grafts were found to be patent in 89% (42/47) of the grafts. Complications associated with PTFE grafts were thrombosis, infections, heart failure, shunt stenosis, and deformity of the pulmonary arteries. Polytetrafluoroethylene grafts for systemic-pulmonary shunts offer good palliation, but the frequency of complications indicates that close follow-up is mandatory to avoid or treat serious sequelae of the complications.

Successful palliation by pulmonary artery banding in absent pulmonary valve syndrome with aneurysmal pulmonary arteries.

Three infants with absent pulmonary valve syndrome were treated between 1977 and 1980. All infants were in critical cardiorespiratory failure refractory to medical therapy. Pulmonary artery banding was performed to reduce the volume occupied by the large pulsating pulmonary artery in a limited mediastinal space. The band reduced tracheobronchial compression and increased effective cardiac output. All three infants survived the procedure and, at follow-up, significant improvement in cardiorespiratory function has been noted, with satisfactory growth. This experience suggests that pulmonary artery banding has a place in the initial management of absent pulmonary valve syndrome, allowing survival so that total correction can be undertaken more safely at a later stage.

"Stone heart" in a neonate.

A neonate presented at this institution in September, 1978, with interrupted aortic arch complex, including ventricular septal defect, atrial septal defect, and patent ductus arteriosus. Additional anomalies included bilateral cleft lip and palate, low set ears, and bilateral colobomas. One-stage total correction of the interrupted aortic arch complex was undertaken with standard hypothermic techniques. The repair was completed within a 65 minute period of circulatory arrest at 18 degrees C, perfusion was re-established, and the patient was returned to normothermia. Tetanic contracture of the myocardium, stone heart, was evident at 27 degrees C. Cardiac action did not resume despite several therapeutic maneuvers, and the infant died on the operating table. Extensive calcium flooding was a notable feature on histological sections of the heart, associated with myofibrillar degeneration (contraction bands). This complication has never been reported before in a neonate with congenital heart disease. Deep hypothermia did not prevent ischemic contracture of the myocardium, and this complication must now be added to an already lengthy list of complications of neonatal heart surgery.

Parachute accessory anterior mitral valve leaflet causing left ventricular outflow tract obstruction. Report of a case with emphasis on the echocardiographic findings.

A case of left ventricular outflow tract obstruction caused by a parachute accessory anterior mitral valve leaflet is presented. The abnormality was detected in an asymptomatic patient by systolic murmur and thrill and was demonstrated by echocardiography, as well as by cardiac catheterization and surgery. These findings are presented. Several previously reported cases of a similar nature are reviewed. An identical case was not found in the English literature.