Hemodynamic effects of dobutamine in children.

Dobutamine is useful for augmenting cardiovasuclar function in adults. However, no information is available on the action of dobutamine in children. To determine its hemodynamic effects in children, we infused dobutamine into 12 children with congenital heart disease during diagnostic cardiac catheterization. We administered dobutamine in two doses: first 2 and then 7.75 microgram/kg per min for 10 minutes each. We meaured heart rate, cardiac output, systemic and pulmonary arterial, right atrial and pulmonary capillary blood pressures before and during the infusion of dobutamine. Systemic and pulmonary vascular resistances, cardiac index and stroke index were calculated. Cardiac output, cardiac index, stroke volume, stroke index and systemic arterial phasic and mean blood pressures increased sugnificantly (P less than 0.05) and pulmonary capillary mean blood pressure decreased significantly (P less than 0.05) during the infusion of each dose of dobutamine compared with control values. Heart rate, pulmonary and right atrial mean blood pressure and systemic and pulmonary vascular resistance were unchanged with either dose of dobutamine. We noted no adverse effect from the drug.     

Using an integrated competence model to evaluate a health visitor cascade training programme for the Family Resilience Assessment Instrument and Tool (FRAIT)

This paper reports on an evaluation of health visitor trainers’ experience of a cascade training programme delivered in Wales, UK. Health visitors used Driscoll’s model (What, So What, Now What) to organise their feedback and an integrated competence model developed by Weeks et al. was used to analyse the feedback via category analysis of free text. As well as feedback on the logistics of running the training, the evaluation allowed for cognitive and functional competence to be identified along with personal and meta competence. There was limited scope for identifying ethical competence in the Health Visitor cascade trainer feedback. Suggestions are made for how this may be addressed.     

A Xp22.11-p21.3 microdeletion in a three-generation family supports male lethality of POLA1 nullisomy resulting in reduced fertility of female carriers

POLA1 encodes a subunit of the DNA polymerase alpha, a key enzyme for the initiation of DNA synthesis. In males, hemizygous hypomorphic variants in POLA1 have been identified as the cause of X-linked pigmentary reticulate disorder (XLPDR) and a novel X-linked neurodevelopmental disorder termed Van Esch-O’Driscoll syndrome (VEODS), while female carriers have been reported to be healthy. Nullisomy for POLA1 was speculated to be lethal due to its crucial function, while the effect of loss of one allele in females remained unknown. Here, we report on a three-generation family harboring a deletion of POLA1 in females showing subfertility as the only phenotype. Our findings show that heterozygous deletions or truncating variants in females with skewed X inactivation do not cause VEODS and support the hypothesis of very early embryonic lethality in males with POLA1 nullisomy.     

Management of surgical complete atrioventricular block in children

Because there is disagreement concerning the efficacy of and indication for permanent pacemaker implantation in children with postoperative complete (third degree) atrioventricular (A-V) block, experience in the management of this problem at one institution was reviewed. Thirty-four patients with postoperative complete atrioventricular block were identified. They ranged In age from 4 months to 22 years and in weight from 4 to 60 kg and were evaluated from 1 month to 20 years postoperatively.

Complete A-V block developed within 24 hours of operation in 28 of the 34 patients. A permanent pacemaker was implanted in 13 of the 28. Death occurred in 4 of these 13 patients and in 5 of the remaining 15 patients who did not have an artificial permanent pacemaker. Complete A-V block developed later than 1 day (2 days to 4 months) postoperatlvely in 6 of the 34 patients; all 6 of these patients survived, and only 3 required permanent pacemaker implantation.

Intracardiac electrophysiologic studies were performed by 14 of the 34 patients. The site of complete block was above the His bundle in 5, within the His bundle in 2, and below the His bundle in 4; it was undetermined in 3. The results of intracardiac electrophysiologic studies are important in delineating the natural history of surgically induced complete A-V block and in the clinical management of this lesion. Permanent pacemaker implantation is indicated if complete A-V block persists longer than 2 weeks postoperatively and if the site of the block is within or below the bundle of His.     

Management of symptomatic infants with anomalous origin of the left coronary artery from the pulmonary artery

There is disagreement concerning the optimal management of infants with congestive heart failure due to anomalous origin of the left coronary artery from the pulmonary artery. This report describes treatment in 23 such patients who had congestive heart failure before age 6 months. Eight patients had an operation in the 1st year of life and only two (25 percent) of these patients survived. Fifteen patients received initial medical treatment, and operation was delayed until an average age of 7.5 years; 13 (87 percent) of these patients survived. The two patients who survived early operation are still alive at an average age of 2.5 years. The 13 survivors in the medical group are still alive at an average age of 14.5 years. The age at onset and the severity of congestive heart failure were similar in the two groups. The frequency of the electrocardiographic pattern of myocardial infarction was similar in both groups. The radiographic cardiothoracic ratio was 0.74 in the surgical and 0.66 in the medical group. In 10 patients the left ventricular ejection fraction was less than 20 percent in the 1st year of life. In 7 of these 10 patients operation was performed before age 1 year and 2 (28 percent) survived; of the 3 patients treated medically, 1 (33 percent) survived.The outcome of surgical or medical treatment of the infant with anomalous origin of the left coronary artery from the pulmonary artery may be biased by patient selection. In the infants with depressed left ventricular function, the results of surgical and medical treatment are equally disappointing. Because coronary arterial surgery in the 1st year of life in infants with severely depressed myocardial function has an extremely high mortality rate (75 percent) and because many symptomatic infants with anomalous origin of the left coronary artery from the pulmonary artery can be treated medically and survive, we recommend delay of operative intervention until at least age 18 months.     

Results of the modified Fontan operation for congenital heart lesions in patients without preoperative sinus rhythm

Preoperative sinus rhythm has been a criterion for the Fontan operation. However, of 297 patients who underwent the Fontan operation between October 1973 and February 1984, 12 (4%) did not have sinus rhythm. The age at operation ranged from 4 to 34 years (median 15). Nine patients had a univentricular heart, two had tricuspid atresia and one had a complex form of transposition. In all 12 patients, 3 to 8 of the 10 proposed criteria for operability were not met. An atrioventricular (AV) conduction abnormality was present in seven patients, six with complete AV block and one with AV dissociation. The patient with complex transposition had complete AV block and atrial fibrillation. Postoperatively, all seven patients continued to have an AV conduction abnormality, and those with complete AV block had a permanent pacemaker implanted. Six of the 12 study patients had atrial flutter or fibrillation refractory to antiarrhythmic medications. Postoperatively, four of the six patients had sinus rhythm. Two of the six patients had complete AV block (including the patient with complex transposition) and both had a permanent pacemaker implanted. Three of the 12 patients died (mortality rate 25%). The nine survivors were followed up for 6 to 55 months; no late deaths occurred. All had marked clinical improvement. This study demonstrates that 1) complete AV block is not a contraindication to the Fontan operation, 2) some patients may not require AV synchrony postoperatively for survival, and 3) postoperative atrial flutter or fibrillation may cease or be easier to control after the Fontan operation.     

Congenital stenosis of individual pulmonary veins: clinical spectrum and unsuccessful treatment by transvenous balloon dilation

Congenital stenosis of the pulmonary veins is a rare but frequently lethal congenital cardiac abnormality. Eight patients with this malformation were diagnosed, evaluated and treated. All eight patients had associated congenital cardiac defects. Two of the eight died, one of sepsis and one after operative pulmonary venoplasty. In three patients who underwent transvenous balloon catheter dilation of the stenosis the procedure provided immediate but transient relief of the stenosis. The prognosis for symptomatic infants with pulmonary vein stenosis is poor and its treatment an enigma.