Discordant spectrum of cardiac manifestations of neonatal lupus in twins.

Congenital complete heart block associated with transplacental passage of maternal autoantibodies reactive with SSA/Ro and SSB/La is a rare disease with significant fetal, neonatal, and childhood morbidity and mortality. We present the case of dichorionic, diamniotic twins (female twin A and male twin B) exposed to maternal Ro and La autoantibodies with different disease expression. Twin A (female) had Mobitz type I second degree atrioventricular (AV) block (Wenckebach); twin B (male) had normal sinus rhythm. Both twins had structurally normal hearts but demonstrated echocardiographic evidence of endocardial fibroelastosis (EFE). Following maternal dexamethasone 4 mg once daily, twin A reverted to sinus rhythm in utero; twin B remained in sinus rhythm throughout pregnancy. Echocardiograms after delivery demonstrated resolution of EFE in both fetuses, and EKGs confirmed sinus rhythm. However, at five months of age, Holter monitor demonstrated first degree AV block and intermittent Wenckebach in twin A. Twin B remains in sinus rhythm. This case is one of only three in the literature that describes Mobitz type I second degree atrioventricular block presenting in fetuses exposed to maternal SSA and SSB autoantibodies and is the first case that we have seen reported in twins. Importantly, this case also adds to the growing body of literature describing EFE as a presentation of neonatal lupus with or without conduction system abnormalities, emphasizes the spectrum of cardiac conduction abnormalities in neonatal lupus syndrome, and raises interesting questions about discordant disease expression in twins.

Autoimmune associated congenital heart block: integration of clinical and research clues in the management of the maternal / foetal dyad at risk.

One of the strongest associations with autoantibodies directed to components of the SSA/Ro-SSB/La ribonucleoprotein complex is the development of congenital heart block (CHB) in an offspring, an alarming prospect facing 2% of primigravid mothers with these reactivities. This risk is 10-fold higher in women who have had a previously affected child with CHB. Anti-Ro/La antibodies are necessary but insufficient to cause disease. In vitro and in vivo experiments suggest that the pathogenesis involves exaggerated apoptosis, macrophage/myfibroblast crosstalk, TGFbeta expression and extensive fibrosis in the conducting system and in some cases surrounding myocardium. A disturbing observation is the rapidity of disease progression, with advanced heart block and life-threatening cardiomyopathy observed <2 weeks from normal sinus rhythm. Once 3rd degree (complete) block is identified, reversal has never been achieved, despite dexamethasone. Current strategies include the evaluation of an early echocardiographic marker of injury, such as a prolonged PR interval and the use of IVIG as a preventative measure for pregnancies of mothers with previously affected children.

Spectrum and progression of conduction abnormalities in infants born to mothers with anti-SSA/Ro-SSB/La antibodies.

The classic cardiac manifestation of neonatal lupus is congenital heart block, attributed to antibody-mediated inflammation and subsequent fibrosis of the atrioventricular (AV) node. In considering the pathologic process of injury it may be that tissue damage results in a range of conduction abnormalities. Identification of less-advanced degrees of block or of fibrosis around the AV node without any conduction abnormality on EKG would support this pathologic model, and serve as a potential marker for treatment if the conduction defect could be shown to progress. To ascertain the spectrum of arrhythmias associated with maternal anti-SSA/Ro-SSB/La antibodies, records of all children enrolled in the Research Registry for Neonatal Lupus were reviewed. Of 187 children with congenital heart block whose mothers have anti-SSA/Ro-SSB/La antibodies, nine had a prolonged PR interval on EKG at birth, four of whom progressed to more advanced AV block. A child whose younger sibling had third degree block was diagnosed with first degree block at age 10 years at the time of surgery for a broken wrist. Two children diagnosed in utero with second degree block were treated with dexamethasone and reverted to normal sinus rhythm by birth, but ultimately progressed to third degree block. Four children had second degree block at birth: of these, two progressed to third degree block. Sinus bradycardia (< 100 bpm) was present in three (3.8%) of 78 fetuses for whom atrial rates were recorded by echocardiogram. Of 40 neonates for whom EKGs were available, the mean atrial rate was 137+/-20 bpm (range 75-200). These data have important research and clinical implications. In contrast to the AV node, permanent sinoatrial nodal involvement is not clinically apparent. Perhaps many fetuses sustain mild inflammation, but resolution is variable, as suggested by the presence of incomplete AV block. Since subsequent progression of less-advanced degrees of block can occur, an EKG should be performed on all infants born to mothers with anti-SSA/Ro-SSB/La antibodies.

The role of positron emission tomography in evaluating mediastinal lymph node metastases in non-small-cell lung cancer.

Positron emission tomography (PET) is a modality that differentiates malignant from benign processes based upon metabolism rather than anatomy. A number of studies have confirmed improved accuracy of PET over computed tomography (CT), but until a few recent studies, most had failed to include satisfactory histologic confirmation. The objective of this study was to compare PET and CT to histologic staging of the mediastinum in patients with non-small-cell lung cancer (NSCLC). Histologic examination of mediastinal lymph nodes (MLNs) was performed on 40 patients with NSCLC at mediastinoscopy and/or at surgical resection. PET scans were interpreted by one of two nuclear medicine physicians, blinded to histology, using CT scans for anatomic localization. CT scans were independently evaluated for mediastinal lymphadenopathy. The overall accuracy, sensitivity, and specificity of PET were 78% (31 of 40), 67% (four of six), and 79% (27 of 34), respectively. The overall accuracy, sensitivity, and specificity of CT were 68% (27 of 40), 50% (three of six), and 71% (24 of 34), respectively. PET was superior to CT at correctly identifying mediastinal nodal metastases; however, both modalities were inferior to the gold standard of surgical staging. PET is more accurate than CT in staging the mediastinum of patients with NSCLC. PET failed to identify lymph node metastasis in 33% of patients with histologically proven MLN involvement, and false positives were present in 15%. At present, mediastinoscopy should remain the standard of care for preoperative mediastinal staging for NSCLC.

Fetal diagnosis of atrioventricular septal defect with dextrocardia in trisomy 18.

On prenatal ultrasound atrioventricular septal defect is often diagnosed in infants with Down syndrome based on an abnormal four-chamber view of the heart. A unique case of atrioventricular septal defect with dextroposition of the heart in an infant with trisomy 18 is presented.

A cross between truncus arteriosus communis and aortopulmonary septal defect: a hitherto undescribed entity.

Case history and necropsy findings of a 5-month-old infant with a unique heart defect with features of truncus arteriosus communis and aortopulmonary defect in combination with severe tricuspid stenosis are presented. There is a wide spectrum of remarkable heart defects between truncus arteriosus communis and aortopulmonary septal defect.

Ventricular preexcitation sensitive to flecainide in late stage chick embryo ECGs: 2,3,7,8-tetrachlorodibenzo-p-dioxin impairs inotropic but not chronotropic or dromotropic responses to isoproterenol and confers resistance to flecainide.

ECGs free of movement artefacts were obtained without anesthesia in 16- to 18-day-old chick embryos close to hatching and used to study the effect of the environmental toxin 2,3,7, 8-tetrachlorodibenzo-p-dioxin (TCDD) on cardiac rhythm and conduction. The ECGs of normal late stage chick embryos exhibited short PR intervals, frequent nonisoelectric PR segments, delta waves, and inverted T waves. Those ECG characteristics are found in patients with the Wolff-Parkinson-White syndrome (WPW) in which they reflect ventricular preexcitation associated with the use of accessory conduction pathways and arrhythmias. Isoproterenol (30 microg/egg) did not alter the ECG preexcitation characteristics. Flecainide, a sodium channel blocker used clinically to suppress WPW accessory pathway activity, at 0.5 to 5 mg per egg diminished the preexcitation and caused atrioventricular (AV) block, supporting the use of accessory pathways together with AV-nodal conduction in normal late stage chick embryos. The findings challenge the dogma that accessory pathways are entirely replaced by AV conduction pathways in late fetal development. TCDD, at 1-2 nmol per egg for 48 h, did not affect heart rate, the increase in heart rate by isoproterenol, or the ECG characteristics, suggesting that short-term TCDD treatment did not affect sinus node function or cardiac conduction. The latter results taken together with prior findings indicate that TCDD differentially impairs the inotropic and lusitropic effects but not the chronotropic or dromotropic effects of isoproterenol. In TCDD-treated embryos, flecainide, tested at 5 mg per egg, caused much less inhibition of preexcitation or production of AV block than in the untreated or solvent-treated controls. The resistance to flecainide represents a new TCDD effect consistent with the reported increase of cardiac myocyte [Ca(2+)](i) by TCDD treatment.

Evaluation of distant metastases in esophageal cancer: 100 consecutive positron emission tomography scans.

BACKGROUND: Pilot studies suggest positron emission tomography (PET) scanning may be superior to conventional imaging in staging esophageal cancer, especially in the detection of radiographically occult distant metastases. This report summarizes our experience with PET in staging esophageal cancer. METHODS: One hundred consecutive PET scans in 91 patients with esophageal cancer referred for surgery were prospectively collected (1995 to 1998) and compared with computerized tomography (CT) and bone scan. PET images were acquired after injection of 18F-fluorodeoxyglucose and evaluated for abnormal uptake. Minimally invasive surgical staging (MIS) and/or clinical correlation were used to confirm or refute imaging results. RESULTS: MIS or clinical correlation confirmed 70 distant metastases in 39 cases. PET detected 51 metastases in 27 of 39 cases (69% sensitivity, 93.4% specificity, 84% accuracy) compared with CT, which detected 26 metastases in 18 of 39 cases (46.1% sensitivity, 73.8% specificity, 63% accuracy) (p < 0.01). CONCLUSIONS: PET was more accurate than CT in detecting distant metastases, but was only 69% sensitive compared with minimally invasive staging.

Pulmonary embolism following laparoscopic antireflux surgery: a case report and review of the literature.

Deep venous thrombosis and pulmonary embolism are concerning causes of morbidity and mortality in patients undergoing general surgical procedures. Laparoscopic surgery has gained rapid acceptance in the past several years and is now a commonly performed procedure by most general surgeons. Multiple anecdotal reports of pulmonary embolism following laparoscopic cholecystectomy have been reported, but the true incidence of deep venous thrombosis and pulmonary embolism in patients undergoing laparoscopic surgery is not known. We present a case of pulmonary embolism following laparoscopic repair of paraesophageal hernia. The literature is then reviewed regarding the incidence of pulmonary embolism following laparoscopic surgery, the mechanism of deep venous thrombosis formation, and the recommendations for deep venous thrombosis prophylaxis in patients undergoing laparoscopic procedures.

Perinatal monitoring of fetal well-being in the presence of congenital heart block.

We present a case of congenital complete heart block associated with maternal autoantibodies in which a normal labor and delivery could safely be allowed to proceed despite the absence of the usual tool of electronic fetal heart rate monitoring for fetal distress, by the technique of rupturing membranes and using a fetal scalp electrode electrocardiographic tracing to assess the fetal atrial rate.

Incidence and risk factors for mitral valve prolapse in severe adolescent idiopathic scoliosis.

Mitral valve prolapse (MVP) is known to be associated with thoracic skeletal anomalies. To determine the incidence and risk factors for mitral valve prolapse in the adolescent population with severe idiopathic scoliosis (IS), a prospective follow-up study on 139 adolescent patients with IS from the Pediatric Orthopedic Service was undertaken. Data collected included age, sex, medical and family history, physical exam, electrocardiogram and echocardiogram, spinal x-rays, and pulmonary function tests. MVP was detected by echocardiogram in 13.6% (19/139) of patients with IS as compared with 3.2% in 154 age- and weight-matched controls (p < 0.006). All patients with MVP were asymptomatic and a systolic click or murmur was detected on the single preoperative exam only in 37% (7/19) of them. Patients with MVP and IS weighed less (45.1 +/- 2.0 vs 51.8 +/- 0.1 kg, p < 0.002) as compared with those IS patients without MVP. The electrocardiogram was abnormal in 21% (4/19) of patients with MVP as compared with only 1.6% (2/120) of patients with IS but no MVP. The two groups did not differ with respect to age at diagnosis, severity of scoliosis, positive family history of scoliosis, or the presence of restrictive lung disease. Though IS was more prevalent in females (79%), the presence of MVP was not related to gender. MVP was persistent in 10 of the 19 patients reevaluated by echocardiogram 2-4 years after spinal surgery. We conclude that MVP is four times more common in patients with severe IS than in the normal adolescent population, and is associated with a lower body weight in IS patients with MVP than in IS patients without MVP. The persistent nature of MVP, even after corrective spinal surgery, may be related to factors other than geometric changes of the heart caused by abnormal thoracic curvature.

Benign fetal bradycardias diagnosed by echocardiography.

Five cases of benign fetal arrhythmias presented with dramatic pictures of sustained irregular bradycardias. These cases were not associated with structural heart disease, the development of hydrops fetalis, or maternal autoantibodies. In all but one case, the arrhythmias resolved before delivery. Two fetuses had 2:1 atrioventricular block and the other three showed group beating due to blocked atrial trigeminy. With regular intermittent reevaluation, and if no signs of hydrops occur, watchful waiting is the suggested therapeutic modality.

Clinical diagnosis of pediatric obstructive sleep apnea validated by polysomnography.

The decision to perform tonsillectomy and adenoidectomy for treatment of pediatric obstructive sleep apnea syndrome is often made on a clinical basis without formal polysomnography. To examine the accuracy of the clinical diagnosis of pediatric obstructive sleep apnea syndrome, we prospectively evaluated 30 children with obstructive symptoms by a standardized history, physical examination, and review of a tape recording of breathing during sleep. On the basis of this clinical evaluation, patients were divided into three predictive groups: (1) definite obstructive sleep apnea syndrome, (2) possible obstructive sleep apnea syndrome, and (3) unlikely to have obstructive sleep apnea syndrome. Nocturnal polysomnography was used to determine the presence or absence of true sleep apnea. Ten of 18 (55.6%) patients predicted clinically to have definite obstructive sleep apnea syndrome had positive nocturnal polysomnographies. Two of six (33.3%) patients predicted to have possible obstructive sleep apnea syndrome had positive nocturnal polysomnographies. One of six (16.7%) patients predicted to be unlikely to have obstructive sleep apnea syndrome had a positive nocturnal polysomnography. Six nocturnal polysomnographies negative by conventional criteria were suspicious for apnea, but considering these positive for obstructive sleep apnea syndrome did not improve the specificity of the clinical prediction. Our results show that clinical assessment of obstructive sleep apnea syndrome in children is sensitive (92.3%) but not specific (29.4%) for making the diagnosis of obstructive sleep apnea syndrome as compared with nocturnal polysomnography and may contribute to the decision to obtain nocturnal polysomnography in specific circumstances.