Atrial flutter in the perinatal age group: diagnosis, management and outcome.

OBJECTIVES: The aim of this retrospective study was to evaluate perinatal atrial flutter (AF) and the efficacy of maternally administered antiarrhythmic agents, postpartum management and outcome. BACKGROUND: Perinatal AF is a potentially lethal arrhythmia, and management of this disorder is difficult and controversial. METHODS: Forty-five patients with documented AF were studied retrospectively. RESULTS: Atrial flutter was diagnosed prenatally in 44 fetuses and immediately postnatally in 1 neonate. Fetal hydrops was seen in 20 patients; 17 received maternal therapy, 2 were delivered and 1 was not treated because it had a severe nontreatable cardiac malformation. In the nonhydropic group of 24 patients, 18 were treated and the remaining 6 were delivered immediately. In the hydropic group, 10 received single-drug therapy (digoxin or sotalol) and 7 received multidrug therapy. In the nonhydropic group, 13 received a single drug (digoxin or sotalol) and 5 received multiple drugs. One patient with rapid 1:1 atrioventricular conduction (heart rate 480 beats/min) died in utero and another died due to a combination of severe hydrops because of the AF, sotalol medication, stenosis of the venous duct and hypoplastic placenta. Of the 43 live-born infants, 12 were in AF at birth. Electrical cardioversion was successful in eight of nine patients. No recurrences in AF have occurred beyond the neonatal period. Four patients with fetal flutter and hydrops showed significant neurological pathology immediately after birth. CONCLUSIONS: Fetal AF is a serious and threatening rhythm disorder, particularly when it causes hydrops, it may be associated with fetal death or neurological damage. Treatment is required and primarily aimed at reaching an adequate ventricular rate and preferably conversion to sinus rhythm. Digoxin failed in prevention of recurrence at time of delivery in a quarter of our patients, whereas with sotalol no recurrence of AF has been reported, suggesting that class III agents may be the future therapy. Once fetuses with AF survive without neurological pathology, their future is good and prophylaxis beyond the neonatal period is unnecessary.

Prenatal pericardiocentesis: its role in the management of intrapericardial teratoma.

A fetus with intrapericardial teratoma had a large pericardial effusion diagnosed by echocardiography. Cardiac tamponade, a common cause of fetal death, was averted by intrauterine pericardiocentesis. Planned obstetric and neonatal management permitted surgical treatment before cardiorespiratory distress developed. The tumor was completely excised and the infant is asymptomatic.

Efficacy and tolerability of cisapride in children.

As gastro-oesophageal reflux disease (GORD) in infants and children is a motility disorder which differs in pathophysiology and clinical course from GORD in adults, prokinetics should be considered the drug of choice in certain circumstances. Indeed, cisapride may result in improvement of feeding tolerance in premature infants. Cisapride has a better tolerability profile than a 'wait-and-see-if-improvement-comes-spontaneously' policy or the other therapeutic options available. A careful and critical review of published data suggests that cisapride may have a QTc-prolonging effect. However, provided the precautions for cisapride administration are followed, the QTc-prolonging effect remains consistently without clinically relevant adverse effects. Correct dosage and avoidance of concurrent treatment with macrolides and/or azoles are the most relevant tolerability recommendations in children. Although there is a need for a prokinetic with better efficacy, cisapride is currently the prokinetic with the best benefit-to-risk ratio available. Thus, withdrawal of cisapride would result in a significantly increased risk for severe complications in infants and children with GORD or other gastrointestinal motility disorders such as chronic intestinal pseudo-obstruction, gastroparesis and feed intolerance in premature infants.

Long-term follow-up of coarctation of the aorta repaired by patch angioplasty.

The long-term complications of patch plasty repair for coarctation of the aorta were assessed retrospectively in 119 patients who were operated upon from 4 days to 13 years of age. There were 7 late deaths and 17 patients were lost to follow-up. Thus 95 patients were followed up for a minimum period of 3 years (mean 6.3 years). In addition, graded exercise tests were performed on 15 patients and 11 normal controls, measuring systolic blood pressure response and arm-leg blood pressure gradients. In this series, 16 patients (17%) were hypertensive, while 25 (26%) had a resting systolic arm-leg gradient greater than 20 mm Hg. Re-coarctation occurred more frequently when surgery had been undertaken under 1 month of age. Review of chest X-rays revealed calcification in the patch in 4 patients, one of whom subsequently went on to aneurysm formation. In a second child aneurysm formation was detected at repeat operation. Exercise tests showed a significantly higher systolic arm pressure in patients (mean: 165.3 mm Hg) when compared to controls (mean: 139.2 mm Hg) (P = 0.017) and a significant increase in arm-leg systolic gradient viz. 36 and 5.9 mm Hg, respectively (P = 0.0016). A good correlation was found between the systolic arm pressure and the systolic arm-leg gradient after exercise (r = 0.822; P = 0.0001). We conclude that the most important long-term complication following an aortic patch plasty, is re-stenosis. The development of an aneurysm was observed only twice. We believe that this apparently rare occurrence, as assessed on chest radiographs; is related to the young age (53% under 1 year) at which the repairs were carried out. Another possible reason may be that the follow-up period is not yet long enough.

Immunological abnormalities in children with acute rheumatic carditis and acute post-streptococcal glomerulonephritis.

Immunological functions were investigated in 10 children with acute rheumatic fever and 11 children with acute nephritis to try and elucidate the cause of heart damage in acute rheumatic fever. Children with acute rheumatic fever and carditis showed an increase in serum IgG, IgA and antistreptococcal antibodies during the acute stage. Lymphocyte transformation responses to phytohaemagglutinin and streptococcal antigens were reduced but this was due to a serum suppressor effect. After recovering from acute rheumatic fever a lymphocytosis and an increased lymphocyte blastogenic response to streptococcal antigen were found. T-cells, T-helper cells and T-suppressor cells showed some changes in acute rheumatic fever but these were not statistically significant in our study. None of the changes in immunological responses that were seen in acute rheumatic fever were found in acute nephritis. These results support the hypothesis that an abnormal immune response to streptococcal products is involved in the development of carditis and the other phenomena observed in acute rheumatic fever.

Surgical correction for one pulmonary artery arising from ascending aorta--report of five cases.

Over a 10-year period we encountered 5 infants with a pulmonary artery branch arising from ascending aorta. Surgical re-implantation of this vessel was carried out at ages 2.5, 5, 8, 9, and 19.5 months. Pre-operative cardiac catheterization demonstrated severely raised pulmonary artery pressures in all, equal to systemic in 3, and suprasystemic in 2. Four patients had origin of the right pulmonary artery from ascending aorta with a left aortic arch, and the remaining patient had an anomalous left pulmonary artery associated with a right-sided aortic arch. All patients had substantial reduction in pulmonary artery pressures immediately following surgery. One patient died 18 days post-operatively from extensive lung disease. In all 4 of the survivors, post-operative cardiac catheterization (11 to 85 months after surgery) has shown a drop in pulmonary artery pressures. One patient has been left with mildly elevated systolic values but normal diastolic levels. In 2 of the children, mild stenosis has been found at the site of reimplantation of the pulmonary artery. This anomaly should always be considered as a cause in the setting of a large left to right shunt with tricuspid incompetence and severe right ventricular hypertrophy. Prompt surgical repair, after confirmation of the diagnosis, should prevent death from heart failure or the development of irreversible pulmonary vascular disease.

Pulmonary hypertension in infants with chronic lung disease: non-invasive evaluation and short term effect of oxygen treatment.

A total of 45 examinations on 30 premature infants with chronic lung disease (CLD) of prematurity were made using Doppler echocardiography. Pulmonary systolic time intervals and tricuspid regurgitant velocity were measured to assess the prevalence of pulmonary hypertension and short term responsiveness of the pulmonary circulation to oxygen. Twelve preterm infants matched for gestational age, served as controls. Tricuspid regurgitation (TR) was detected in 14 of the patients. Eleven of those with TR had pulmonary hypertension, of whom eight responded to oxygen treatment. Of the remaining three patients with 'fixed' pulmonary hypertension, one subsequently died. The detection of TR was the basis of the preferred method for measuring pulmonary artery pressure (Ppa) non-invasively, but the degree of correlation between the Ppa estimated from TR and pulmonary systolic time intervals was high (r = -0.84, p = 0.001). In the absence of TR, systolic time intervals are an effective way to monitor pulmonary artery pressure in infants with CLD. Without these measurements, it would have been impossible to predict which subjects had pulmonary hypertension, and which might respond to oxygen treatment.

Complication of intra-aortic balloon pumping in a pediatric patient.

A serious complication was seen following insertion of an intra-aortic balloon pump in the ascending aorta in a pediatric patient. The catheter initially coursed to the left subclavian artery from which it folded upon before finding its way in the descending aorta. We recommend that a suitably curved J-tip guidewire be used to guide the IABP balloons distal to the aortic arch into the descending aorta, so as to avoid potentially fatal complications.

Mid-term results of the modified Senning operation for cavopulmonary connection with autologous tissue.

UNLABELLED: The aim of this study was to determine the results and mid-term outcome of a modified Senning technique using autologous tissue for total cavopulmonary connection. The study involved 31 children, 8 with tricuspid atresia and 23 with complex congenital heart disease. In this operation, a flap of autologous atrial free wall tissue was used to tunnel inferior vena caval blood to the pulmonary arteries. An additional Damus-Kay-Stansel operation was required in 9 patients with subaortic obstruction. RESULTS: the early mortality rate was 16% (5 out of 31 patients) and there were four late deaths. COMPLICATIONS: Pleural effusions were encountered in 17 patients, of whom 4 had a concomitant pericardial effusion. Diaphragmatic paralysis was diagnosed in five patients, one of whom underwent surgical plication. Median hospital stay was 26 days. The 1- to 5-year actuarial survival was 68.6%. Follow-up ranged from 10 months to 7.1 years, mean 3.2 years. A serious atrial arrhythmia was diagnosed in one patient and another one died, possibly from rhythm disorders. Exercise tolerance and quality of life has improved in all but one of the survivors. Although follow-up is short, we have thus far witnessed a low incidence of hemodynamic and rhythm disturbances with this modification of the cavopulmonary connection.

Successful use of an intraosseous infusion in an 800 grams preterm infant.

An intravascular access line for the administration of life support drugs and volume expanders may be particularly difficult, especially in very small premature babies. We report on the successful use of an intraosseous accessline in an 800 grams preterm infant for the administration of drugs and fluid. The use and technique of an intraosseous access is an important emergency alternative which may be lifesaving, even in very preterm babies, when other methods fail.

Comparison of formulae for heart rate correction of QT interval in exercise ECGs from healthy children.

OBJECTIVE: To investigate the differences in four formulae for heart rate correction of the QT interval in serial ECG recordings in healthy children undergoing a graded exercise test. SUBJECTS: 54 healthy children, median age 9.9 years (range 5.05-14.9 years), subjected to graded physical exercise (on a bicycle ergometer or treadmill) until heart rate reached > 85% of expected maximum for age. DESIGN: ECG was recorded at baseline, at maximum exercise, and at one, two, four, and six minutes after exercise. For each stage, a 12 lead digital ECG was obtained and printed. In each ECG, QT and RR interval were measured (lead II), heart rate was calculated, and QTc values were obtained using the Bazett, Hodges, Fridericia, and Framingham formulae. A paired t test was used for comparison of QTc, QT, and RR interval at rest and peak exercise, and analysis of variance for all parameters for different stages for each formula. RESULTS: From peak exercise to two minutes recovery there was a delay in QT lengthening compared with RR lengthening, accounting for differences observed with the formulae after peak exercise. At peak exercise, the Bazett and Hodges formulae led to prolongation of QTc intervals (p < 0.001), while the Fridericia and Framingham formulae led to shortening of QTc intervals (p < 0.001) until four minutes of recovery. The Bazett QTc shortened significantly at one minute after peak exercise. CONCLUSIONS: The practical meaning of QT interval measurements depends on the correction formula used. In studies investigating repolarisation changes (for example, in the long QT syndromes, congenital heart defects, or in the evaluation of new drugs), the use of an ad hoc selected heart rate correction formula may bias the results in either direction. The Fridericia and Framingham QTc values at one minute recovery from exercise may be useful in the assessment of long QT syndromes.

Posterior d-transposition of the great arteries with an unusual form of aortic obstruction.

An unusual case of posterior transposition of the great arteries, with previously undescribed aortic obstruction is described. The patient, who underwent an arterial switch operation, was found at surgery to have a mass of myxomatous tissue arising from the tricuspid valve. This finding was responsible for the hemodynamically significant aortic stenosis.

Subclinical cardiomyopathy in Becker muscular dystrophy.

OBJECTIVE: To investigate the prevalence, age distribution, and spectrum of cardiac involvement in a cohort of patients with Becker muscular dystrophy. DESIGN: A prospective non-invasive study with clinical, electrocardiographic, and echocardiographic assessment. PATIENTS: 19 patients (age range 16-41 years) with Becker muscular dystrophy attending the Muscle Clinic at Hammersmith Hospital and 22 healthy controls (age range 22-36 years). RESULTS: 17 patients (89%) were symptom free; two had exertional dyspnoea. Three had a past history of acute pericarditis. The electrocardiogram was abnormal in 14 patients (74%). Intraventricular conduction delay or right bundle branch block was present in eight (42%). Three (16%) had tall R waves (R/S > 1) in lead V1 in the absence of right bundle branch block and eight (42%) had Q waves in the lateral and inferolateral leads. The PQ interval was significantly shorter in patients with Becker muscular dystrophy (p < 0.01). Echocardiography showed left ventricular dilatation in seven patients (37%) and 12 (63%) had subnormal systolic function caused by global hypokinesia (fractional shortening < 27%). Six of these patients were under the age of 22 years. Patients with Becker muscular dystrophy had significant reduction of both fractional shortening and corrected mean velocity of circumferential shortening compared with controls. No correlation was found between fractional shortening and age. The third filling fraction was significantly reduced in patients with Becker muscular dystrophy (p < 0.05), although other indices of diastolic function (isovolumic relaxation time and E/A ratios) were not significantly different. CONCLUSIONS: Though most patients with Becker muscular dystrophy were symptom free, a high percentage had evidence of a subclinical cardiomyopathy. Electrocardiography showed that the inferolateral and posterior segments of the left ventricle tended to be affected and may show evidence for conduction tissue disease. Echocardiography showed that most patients had left ventricular dilation and global hypokinesia. The severity of left ventricular disease was unrelated to age; some younger patients had severe left ventricular dysfunction. All patients with Becker muscular dystrophy should have echocardiographic assessment of left ventricular function.

Cisapride plasma levels and corrected QT interval in infants undergoing routine polysomnography.

BACKGROUND: Reported QTc prolongation associated with cardiac arrhythmia in a small number of children undergoing cisapride therapy and lack of pharmacokinetic correlation provided the impetus for this prospective study. The authors evaluated the relation between cisapride plasma concentrations, the electrocardiographic QT interval, and cardiac rhythm in infants undergoing routine 8-hour polysomnography. METHODS: A total of 211 infants were enrolled: 84 (17 born prematurely) undergoing cisapride therapy for at least 4 days for suspected gastroesophageal reflux and 127 controls (10 born prematurely), aged between 1 week and 13.5 months. Infants underwent continuous bipolar limb lead I recording during routine 8-hour polysomnography. QT intervals and heart rate were measured at hourly intervals. The morning after polysomnography, 12-lead electrocardiography was performed (1 hour after cisapride administration). Cisapride plasma concentrations were determined immediately before and 1 to 2 hours after administration. Serum electrolyte concentrations were measured. RESULTS: The administered cisapride dose ranged from 0.35 to 1.55 (mean, 0.81, median 0.79) mg. kg-1. d-1. Cisapride plasma concentrations were significantly higher in infants younger than 3 months of age. Cisapride-treated infants younger than 3 months of age had longer QTc intervals compared with age-matched controls. Heart rate was similar for cisapride-treated and control infants. No arrhythmia or atrioventricular conduction abnormalities were observed. CONCLUSIONS: At comparable doses of cisapride and comparable plasma concentrations, the QTc was significantly higher in infants younger than 3 months of age. This confirms age-dependent cisapride pharmacokinetics in the first 10 to 12 weeks strongly correlated with changes in body weight and may also suggest an altered ability of infants younger than 3 months of age to metabolize cisapride. The clinical significance and risk of the increased QTc interval is unclear. Cisapride should be judiciously prescribed in infants younger than the age of 3 months and electrocardiography should be performed before and during therapy.

The effect of cisapride on the corrected QT interval and QT dispersion in premature infants.

BACKGROUND: Cisapride is used frequently in premature neonates as a gastrointestinal prokinetic drug. Concerns exist, however, about its safety because of its effect on the QT interval. Premature infants could be at higher risk for side effects because of their immaturity. This prospective study investigated the pharmacokinetics of cisapride and its effects on corrected QT interval (QTc) and QT dispersion in premature infants. METHODS: Electrocardiogram examination was performed just before and after 72 hours of treatment with cisapride (0.2 mg/kg per dose, four times daily) in 10 premature infants. Trough and anticipated peak plasma level of cisapride and norcisapride were quantified after 72 hours of treatment. Results were compared with a cohort of 41 term infants aged 0 to 3 months receiving cisapride treatment. RESULTS: The QTc interval increased significantly from 423 ms to 461 ms after 72 hours of treatment (P = 0.0007). No effect was seen on QT dispersion (44.3 ms vs. 45.9 ms). The change in QTc interval was inversely related to postnatal age (R2 = 0.52; P = 0.02), whereas there was no correlation with gestational age or plasma levels of cisapride or norcisapride. Trough and anticipated peak plasma levels of cisapride and norcisapride were significantly higher in the premature infants compared with the term infants aged 0 to 3 months (P < 0.001). CONCLUSIONS: Premature infants less than 1 month of age could be at higher risk for cardiac side effects of cisapride when used in the same dosage as in older infants. The daily dose should be reduced (0.1 mg/kg per dose, maximum four times daily), and the QTc interval should be monitored closely. The benefits and safety of cisapride in premature infants less than 1 month of age should be reconsidered.

Left-ventricular inflow obstruction due to a dilated coronary sinus mimicking Cor Triatriatum.

Persistence of the left superior vena cava with drainage to the coronary sinus is a common congenital anomaly. We report an infant with such a malformation associated with marked enlargement of the coronary sinus, which produced partial supramitral obstruction and consequently impairment to the left-ventricular inflow. The patient pre-sented with cardiac failure in infancy and features mimicking cor triatriatum. Surgical relief of the supramitral obstruction resulted in immediate reversal of the pulmonary hypertension, with clinical improvement. This rare entity, only once previously reported, is an unusual cause of pulmonary hypertension in infancy.

Coarctation and coarctation syndrome. A 5-year review.

The management of and results of treatment in 57 children with coarctation of the aorta are presented. In this series, 75% of the patients presented in the 1st year of life and 51% presented as neonates. Among the 50 patients who underwent surgery the total surgical mortality rate was 14%. The higher mortality in young infants is closely related to associated cardiac anomalies. We suggest that neonates with coarctation presenting with heart failure should be operated on early, as this significantly reduces the mortality.