Coarctation of the aorta: nonsurgical treatment using stent implantation

INTRODUCTION

Coarctation of the aorta (CoA) accounts for 5%-8% of all congenital heart defects. If left untreated, most patients with significant CoA will have varying degrees of morbidity (e.g. hypertension, stroke, collateral formation and ventricular hypertrophy), possibly even mortality. Traditionally, treatment for this condition is surgical. Herein, we report stenting during catheterisation as an alternative nonsurgical treatment option for patients with CoA, and present the treatment outcomes of patients who underwent this treatment option.

METHODS

We retrospectively reviewed four patients (2 men and 2 women; age range 20-41 years) who underwent CoA stenting under general anaesthesia for the treatment of native CoA or restenosis of CoA at our institution. Three patients had a 40-mm Palmaz stent inserted, while one had a 39-mm Cheatham-Platinum covered stent inserted. Angiography and measurement of pressure gradients were performed before and after stent implantation to ensure good treatment outcomes.

RESULTS

The patients' treatment outcomes were good, with a significant reduction in pressure gradients across the narrowed segments. Angiography showed relief of CoA. The patients were followed up for 1-3 years, during which no complications were noted.

CONCLUSION

This is the first reported series in Singapore on the nonsurgical treatment of CoAs in adult patients using stents during interventional cardiac catheterisation. This less invasive procedure may lead to a new paradigm shift with regard to the treatment of CoA.

Isolated cleft mitral valve with severe regurgitation resulting in a left inferior pulmonary vein varix diagnosed from cardiovascular magnetic resonance imaging

Isolated cleft mitral valve (ICMV) is a rare entity not known to be related to pulmonary atresia with ventricular septal defect (PA-VSD). This report describes the use of cardiovascular magnetic resonance (CMR) imaging to diagnose ICMV in a patient with repaired PA-VSD who presented with incidental severe mitral regurgitation (MR) on follow-up echocardiography. An associated pulmonary varix secondary to the severe MR also was shown by CMR.

The Effects of Three Factor VII Polymorphisms on Factor VII Coagulant Levels in Healthy Singaporean Chinese, Malay and Indian Newborns

Factor VII (FVII) is an independent risk factor for coronary artery disease. Three polymorphisms of the factor VII gene (F7) were studied in a group of healthy newborns comprising 561 Chinese, 398 Malays and 226 Asian Indians from Singapore. The allele frequencies of 3 polymorphisms (R353Q, Promoter 0/10bp Del/Ins and Intron 7) in the FVII gene were ascertained through genotyping by polymerase chain reaction and restriction digestion of amplified fragments. In Chinese the minor allele frequencies are Q: 0.04, Ins: 0.03, R7: 0.44; Malays, Q: 0.06, Ins: 0.10, R7: 0.41; and Indians, Q: 0.25, Ins: 0.23, R7: 0.43. Strong linkage disequilibrium (Delta > 0.7) is observed between the 0/10 bp and the R353Q sites in all ethnic groups. We conclude that: (i) the prevalence of the minor Q and Ins alleles of the R353Q and 0/10 bp polymorphisms are significantly higher in the Indian newborns than the Chinese and Malays; (ii) the Q allele is significantly associated (p = 0.01) with a lower plasma FVII coagulant level in the Indian and Malay neonates; and this polymorphism explains up to 3.8% of the variance in FVII coagulant levels; (iii) there is no significant difference in allele frequencies of the three polymorphisms between neonates with and without family histories of CAD.

Immunosuppressive therapy in acute myocarditis: an 18 year systematic review

BACKGROUND

Immunosuppressive therapy is reportedly ineffective in adults with acute myocarditis.

AIMS

To systematically review the impact of immunosuppressive therapy on the outcome of acute myocarditis in children.

METHODS

A literature search for articles published from 1984 to 2003 was conducted with the following keywords: myocarditis, dilated cardiomyopathy, and immunosuppression. The relevant studies were systematically reviewed and comparison of treatment effect was made by calculating the odds ratio (OR) and confidence interval (CI) using the exact method based on the exact discrete reference distribution.

RESULTS

Of the 1470 articles found, only nine studies were eligible. The odds for improvement with immunosuppression was between 4.33 (95% CI 0.52 to 52.23) and 2.7 (95% CI 0.59 to 14.21). Addition of a second immunosuppressive agent to prednisolone only proved effective in one randomised controlled trial (OR 0.09, 95% CI 0.01 to 0.52). Heterogeneity of these studies precluded pooled odds ratio.

CONCLUSION

Current data suggest that immunosuppressive therapy does not significantly improve outcomes in children with acute myocarditis and there is insufficient evidence for its routine use. However, statistical power to detect a significant difference in the treatment effect may be limited because of the small number of subjects. This, together with problems of diagnosis, varying treatment practices, and a relative lack of evidence based guidelines would support efforts for a large multicentre, randomised controlled trial to better define the role of immunosuppression in acute myocarditis.

A case series of six children with primary pulmonary hypertension

INTRODUCTION

Primary pulmonary hypertension is an uncommon but serious disease in children. Management is difficult despite recent advances in pharmacotherapy.

CLINICAL PICTURE

We reviewed patients with this condition with respect to their presenting symptoms, investigations, treatment and outcome.

TREATMENT

These children were treated with individualised combinations of oxygen, diuretics and calcium antagonists.

OUTCOME

In our follow-up of 5 children, 4 had died.

CONCLUSION

This condition is irreversible and progressive with a high mortality rate. A better understanding of, and research into, the pathogenesis would hopefully lead to the formulation of improved therapeutic strategies for this condition.

Liver transplantation in a child with severe hypercholesterolaemia in Alagille syndrome

INTRODUCTION

Liver transplantation is a curative treatment modality in children with end stage liver disease in Alagille syndrome.

CLINICAL PICTURE

We report a 3-year-old child with this condition who had severe hypercholesterolaemia, pruritus and extensive xanthomatosis.

TREATMENT

Liver transplantation was performed in this patient.

OUTCOME

He recovered well with normalisation of his lipid profile. This procedure also resulted in resolution of the disfiguring xanthomatosis.

Abdominal coarctation and Alagille syndrome

Structural cardiac defects such as peripheral pulmonary stenosis are well-described in Alagille syndrome (AS), which is transmitted in an autosomal dominant inheritance. The genetic defect, with incomplete penetrance and variable expression, is localized to the short arm of chromosome 20. Abdominal coarctation is an uncommon congenital anomaly, with a spectrum of symptoms that may range from hypertension, intermittent claudication to abdominal pain. The association of abdominal coarctation with AS is rarely described. We report such a patient who also had aberrations of the visceral vascular supply involving the celiac, splenic, and superior mesenteric arteries. The indications to treat the coarctation, and in the context of a patient with AS, in whom liver transplantation may be contemplated at some stage, merit discussion.

A case report on the perinatal management of a 30-week preterm baby with congenital complete heart block

INTRODUCTION

Congenital complete heart block is an uncommon condition in the newborn, but is known to occur with maternal systemic lupus erythematosus.

CLINICAL PICTURE

This paper presents one such baby with complete heart block who was born premature (after a gestation of 30 weeks) and weighing 759 g.

TREATMENT

Continuous isoprnaline infusion was initially used to support the baby while her other neonatal problems were treated. A Medtronics VV1 pacemaker was subsequently inserted to maintain a heart rate that would be more physiologically acceptable for the patient.

OUTCOME

This baby is currently thriving well, having been followed up for one year.

CONCLUSIONS

The management issues, encompassing maternal and neonatal problems, and a review of current literature on this condition are discussed.

Initial experience of radiofrequency catheter ablation of supraventricular tachycardia in paediatric patients

INTRODUCTION

The management of supraventricular tachycardia (SVT) in paediatric patients until recently has frequently been pharmacologic therapy, but this approach suffers from the drawbacks of treatment failure, development of drug intolerance and/or side-effects.

AIM

In keeping with recent advances in paediatric cardiology, we share our experience with radiofrequency catheter ablation as an alternative and definitive modality of therapy.

MATERIALS AND METHOD

4 young patients with recurrent SVT underwent electrophysiologic study followed by radiofrequency ablation of the accessory pathways.

RESULTS

Resolution of symptoms was achieved in all patients and no major complication was encountered.

CONCLUSIONS

The ability to ablate permanently the reentrant circuit responsible for SVT has now permitted cure by non-surgical means, and is an important alternative to drug therapy in the management of SVT in children.

Influence of surgery on aortic valve prolapse and aortic regurgitation in doubly committed subarterial ventricular septal defect

Doubly committed subarterial ventricular septal defects should be closed surgically once aortic valve deformity is present before the onset of aortic regurgitation.

Outcome of surgical closure of doubly committed subarterial ventricular septal defect

BACKGROUND

From 1986 to March 1997, 128 patients diagnosed to have doubly committed subarterial ventricular septal defects (VSD) were reviewed. Patients with aortic regurgitation (AR), and aortic valve (AV) deformity or a large left-to-right shunt across the VSD were offered operation. Forty-five patients (27 men, 18 women) agreed to surgical closure of their VSDs.

METHODS

Thirty-eight patients had VSD closure alone, and 7 had an additional AV repair. Other associated defects corrected at operation were closure of atrial septal defects, closure of other ventricular septal defects, ligation of patent ductus arteriosus, and repair of ruptured sinus Valsalva aneurysm.

RESULTS

There was no mortality nor major morbidity associated with operation. In the 26 patients with AR and AV deformity preoperatively, valve repair was performed in 6 patients. The condition of AR improved in 4, and remained unchanged in 22 patients. In the 10 patients with a deformity of the AV and no AR preoperatively, the condition remained unchanged in 5 patients, from whom 1 had valve operation, but progressed in 5 patients postoperatively at a mean follow-up of 6.4 years. In 9 patients with no deformity of the AV and no AR preoperatively, there was no postoperative AR and no progress of valve deformity.

CONCLUSIONS

Excellent results were obtained with VSD closure and AV repair. Surgical closure of VSD, if performed before the onset of AV deformity, may prevent progressive AR. If AV repair is performed after the onset of AV deformity, progressive AR may not always be prevented.

Hepatopulmonary syndrome: a rare complication of chronic liver disease in children

An 11-year-old boy with congenital hepatic fibrosis presented with cyanosis at the National University Hospital. Echocardiogram revealed a structurally normal heart with good ventricular function. A pulmonary cause of his cyanosis was suggested on macroaggregated albumin scan and selective pulmonary artery angiogram. Arterial hypoxaemia secondary to intrapulmonary arteriovenous shunting in chronic liver cirrhosis can lead to permanent cyanosis. The potential for a complete reversal of this condition after liver transplantation indicates that arterial hypoxaemia, rather than being a contraindication, should be a reason for early liver transplantation.

Bidirectional cavopulmonary anastomosis

The Fontan operation has been used to palliate patients with a functional single ventricle. In many such patients the operative risk for a Fontan procedure is high. The bidirectional cavopulmonary anastomosis (BCPA) is a useful intermediate palliative procedure before Fontan correction. It may reduce the deleterious sequelae of chronic hypoxaemia and long-term ventricular overload, thus yielding a more suitable Fontan candidate. We reviewed our experience of 9 patients with univentricular hearts who were at the time of the BCPA not considered suitable candidates for conventional Fontan operation. Two patients had double inlet right ventricle (DIRV) with pulmonary stenosis (PS) and ventricular septal defect (VSD), 2 had univentricular heart, 4 had tricuspid atresia (TA) and hypoplastic right ventricle (RV), 1 patient had atrioventricular septal defect (AVSD) with double outlet right ventricle (DORV) with hypoplastic RV. Two of the 9 patients had bilateral superior vena cavae. All except one had undergone prior palliative operations. The mean age at BCPA was 4.7 years (range 1.5 years to 6 years) and the mean weight at surgery was 15 kg (range 7 to 22 kg). There were no operative deaths. The mean hospitalization stay was 8.5 days (range 5 to 13 days) with a mean follow up of 14 months. Median oxygen saturation improved from 78.7 +/- 6.3% to 85.9 +/- 3.9%. The BCPA is a useful palliative procedure to stage Fontan type reconstruction in selected patients with univentricular hearts.

Abnormal electrocardiographic patterns in renal failure. Ventricular tachycardia

A 9-year-old girl was diagnosed to have renal failure. However, her family has not been compliant with medical treatment and opted for traditional therapy instead. She was admitted in an ill state with fluid overload. What is the ECG diagnosis?

The athlete's heart: is this an entity in paediatrics?

A case report of a boy who demonstrates features of an athlete's heart, associated with dilatation of the coronary artery, is presented. The importance of distinguishing this benign condition from pathologic causes such as cardiomyopathy, and risk of sudden death in these athletes is discussed.

Cardiac dysrrhthmia in systemic disease

This is an ECG of a 6-year-old girl. She presented to us for management of epilepsy. Magnetic resonance imaging (MRI) of the brain showed multiple lesions consistent with cortical and subcortical tubers. There were also achromic spots on her skin and echocardiography demonstrated a rhabdomyoma near the right ventricular outflow tract. A diagnosis of tuberous sclerosis, an autosomal-dominantly inherited condition, was made. What is abnormal about the ECG?

The Polarprobe--emerging technology for cervical cancer screening

The Polarprobe is a portable non invasive electronic device designed for the detection of cervical precancer and cancer. It measures both electrical and optical properties of cervical tissue to allow a real time comparison with a databank of previously determined cervical tissue types. The need for additional tests to augment or even replace the Papanicolaou smear has partly prompted its development. Indeed it has been shown to be associated with less pain and anxiety than the smear and has the capability of encouraging women to attend for screening. Some of the preliminary clinical trials on the Polarprobe are reported as well as the ongoing developments and modifications to the device.

Cardiac manifestations in tuberous sclerosis: a 10-year review

OBJECTIVE

Tuberous sclerosis is a genetic disorder with multisystem involvement. The aim of this study was to focus primarily on the cardiac aspects of this condition.

METHOD

This review included 10 children with tuberous sclerosis presenting to our department during a 10-year period.

RESULTS

From our data, 80% were found to have cardiac involvement. There was an equal prevalence of neurologic complications.

CONCLUSIONS

Cardiac tumours and seizures were the most common problems encountered. Whereas most patients had no symptoms referable to the cardiovascular system and required no active intervention, many of those with neurologic involvement needed appropriate treatment.

Transcatheter embolization of coronary artery fistula with controlled release coils

The treatment for large congenital coronary cameral fistulas has been surgical but with advances in interventional catheterization techniques transcatheter embolization of these fistulas with coils or detachable balloons is now possible. This report describes occlusion of a congenital coronary arteriovenous fistula in a 6-year-old girl.

Use of a reformulated Oka strain varicella vaccine (SmithKline Beecham Biologicals/Oka) in healthy children

The first live-attenuated Oka strain varicella vaccines needed to be stored at -20 degrees C. Reformulation of this vaccine by SmithKline Beecham Biologicals has provided a vaccine shelf life of up to 2 years when stored at +4 degrees C to +8 degrees C. In this study the immunogenicity and reactogenicity of two different production lots of this reformulated vaccine at two different titres each, which corresponded to the release and expected expiry titres, were evaluated. A double-blind randomised clinical trial was conducted in healthy children aged from 9 to 24 months. Immunogenicity was assessed by the measurement of varicella specific antibodies in paired serum samples taken before and from 35 to 63 days post vaccination. Reactogenicity was assessed by the evaluation of any untoward reactions occurring up to 42 days post vaccination. In order to assess protective efficacy, parents of these subjects were contacted approximately 6 months after completion of the trial. One hundred and ninety-one subjects were recruited into the study. Of the 181 initially seronegative subjects who completed the trial according to the protocol, 179 showed seroconversion (98.9%). Reactions to the vaccine were minor and observed in 46/191 (24%) of subjects. Rashes were present in 19, fever in 22, and both fever and rash in 5. Rashes were mainly maculo-papular in nature but were vesicular in 6. Febrile reactions were shortlived. After a 6-month follow up period, attenuated varicella with minor clinical symptoms was diagnosed in 6/52 vaccinees who had close contact with natural varicella (attack rate = 11.5%).

CONCLUSION

This reformulated vaccine was well tolerated, highly immunogenic and provided protection against varicella. In increased stability allowing refrigerator storage makes it a good candidate for mass vaccination programmes.

Prevalence and severity of asthma, rhinitis, and eczema in Singapore schoolchildren

This study was part of an international effort to evaluate the epidemiology of asthma and allergic diseases around the world. The aim was to assess the prevalence and severity of these disorders in Singapore schoolchildren. The international study of asthma and allergies in childhood (ISAAC) written questionnaire was administered to 6238 schoolchildren. The respondents were parents of a 6-7 year cohort (n = 2030), and schoolchildren aged 12-15 years (n = 4208). The overall cumulative and 12 month prevalence of wheezing were 22% and 12%, respectively. The prevalence of doctor diagnosed asthma was 20%. Rhinitis was reported by 44% and chronic rashes by 12%. Multiple logistic regression analysis showed that a higher prevalence of wheezing and rhinitis was associated with males, and subjects of higher socioeconomic status (based on type of housing and total family income). More severe asthma related symptoms were present in Malays and Indians than in the Chinese. Allergic disorders are common in Singapore and prevalence is comparable to some populations in the West. Demographic and socioeconomic factors appear to influence the prevalence and severity of these disorders.

Paediatric pacemaker implant using the transvenous endocardial approach

The advent of the pacemaker has opened a whole new dimension to management in cardiology. Although its use has been well described in adults, its role in paediatric cardiology has proven to be equally exciting and challenging. We describe a case of a child with complex cyanotic heart disease who had an insertion of a cardiac pacemaker via the transvenous route, one of the youngest to be performed locally. This article also highlights the pertinent features of paediatric pacemaker therapy, including its indications and implantation technique.

Effects of an acaricide on asthmatic children with house dust mite allergy

D'Allergen is a recently available acaricidal and allergen reducing agent. To study any beneficial effects of treating houses with this agent in asthmatic children with dust mite allergy, histamine bronchial responsiveness was measured in 18 children before and 6-8 weeks after their homes were treated with the agent. Comparisons were with nine similar asthmatics whose homes were not treated. The mean provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 s (PC20) increased from 1.02 mg/L to 2.07 mg/L in all 18 children who were studied (1.01 doubling doses). Bronchial responsiveness was relatively unchanged in a well matched control group of nine children studied over comparable time periods (PC20 pre was 1.25 mg/L, PC20 post was 0.67 mg/L). The results suggest that treating homes with D'Allergen reduces bronchial reactivity in asthmatic residents with house dust mite allergy.

Day care and asthma morbidity

An association between attendance at day care centres and lower respiratory symptoms among pre-school asthmatic children who were attending follow-up appointments at a specialist respiratory outpatient clinic was studied. Parents of 69 children completed a questionnaire. Because of the variation in the age distribution of the two groups, analysis was restricted to children aged 2-4 years old; results from 49 children were analysed. Cough, wheeze at night and wheeze on waking occurred significantly more frequently in the two weeks prior to clinic visits among asthmatics attending day care. Among asthmatic children requiring specialist outpatient follow up, those attending day care are more likely to be troubled by lower respiratory symptoms than those looked after at home.

Helicobacter pylori infection in children with recurrent abdominal pain

Forty-eight patients with recurrent abdominal pain were studied endoscopically for the presence of gastritis and Helicobacter pylori infection. Fifteen of these children had histological evidence of gastritis with eight of them having concomitant H. pylori infection. The majority of those with H. pylori infection had severe degrees of acute following chronic gastritis.