Profile of plasma free amino acids, carnitine and acylcarnitines, and JAK2v617f mutation as potential metabolic markers in children with type 1 diabetic nephropathy

Fifty diabetic nephropathy (DN) children with type 1 diabetes mellitus (T1DM) and 50 healthy matched controls were included. Chromatographic assays of 14 amino acids, free carnitine and 27 carnitine esters using high-performance liquid chromatography/electrospray ionization-mass spectroscopy, and genetic testing for JAK2v617f mutation using real-time PCR were performed. Patients had significantly lower levels of tyrosine, branched-chain amino acids (BCAAs), and BCAA/AAA (aromatic chain amino acids) ratios, glycine, arginine, ornithine, free carnitine and some carnitine esters (C5, 6, 12 and 16) and higher phenylalanine, phenylalanine/tyrosine ratio and C18 compared with the controls and in the macro-albuminuria vs. the microalbuminuria group (p < 0.05 for all) except for free carnitine. Plasma carnitine was negatively correlated with eGFR (r = -0.488, p = 0.000). There were significant positive correlations between tyrosine with UACR ratio (r = 0.296, p = 0.037). The plasma BCAA/AAA ratio showed significant negative correlations with UACR (r = -0.484, p = 0.000). There was a significantly higher frequency of the JAK2V617F gene mutation in diabetic nephropathy patients compared with the control group and in macro-albuminuria than the microalbuminuria group (p = 0.000) for both. When monitoring children with T1DM, plasma free amino acids and acylcarnitine profiles should be considered, especially if they have tested positive for JAK2V617F for the early diagnosis of DN.

The impact of breast cancer knowledge and attitudes on screening and early detection among an immigrant Iranian population in southern California

Few studies explored factors influencing breast cancer screening and early detection behaviors among immigrant Iranian women residing in the USA. Using a cross-sectional survey, a convenience sample of 319 Iranian American women was selected to investigate the impact of breast cancer knowledge and attitude on screening. A self-administered questionnaire assessed breast cancer screening knowledge, attitude, and mammography use (ever, previous year, and future intention). 79 % of the women in the study reported ever receiving at least one mammogram and 74 % received a mammogram in the past year. Personal attitude had an independent significant effect on: mammography use in the last year, ever use of mammography, and future intention to screen. Knowledge and morality-induced attitude influenced screening behavior but not significantly. Interventions targeting breast cancer screening among immigrant Iranian women in the USA should focus on enhancing personal attitudes in order to influence actual screening behavior.

Lack of post-exercise depression of corticospinal excitability in patients with Parkinson's disease

There is lack of clarity in the literature over whether patients with Parkinson's disease (PD) show the same post-exercise depression of corticospinal excitability as is usually observed in healthy control. This study set out to resolve the problem. Ten patients with idiopathic PD and 10 age-matched controls were included in this study. Each subject performed a submaximal sustained voluntary contraction of the right first dorsal interosseous muscle (FDI) for 10 min or until force could no longer be sustained. Resting motor threshold, motor-evoked potential (MEP), input-output curve, cortical silent period duration, interference pattern (IP) and M/F ratio were recorded at baseline, immediately after fatigue and after 20 min rest. Immediately after exercise, decreased MEP amplitude and increased cortical SP duration were observed in the control group whilst no such changes were observed in PD patients. The input-output curve was also significantly suppressed only in controls, but not in patients. The amplitude of IP was significantly reduced immediately after exercise in both PD patients and controls. Almost all these changes returned nearly to baseline values after 20 min rest. The amount of exercise was approximately equal in both groups because the effect on M-waves and EMG amplitude was similar. However, the expected decline in corticospinal excitability was absent in PD patients. The absence of this effect in PD patients may reflect reorganization of motor commands in response to basal ganglia deficit.

Long-term results of pulmonary balloon valvulotomy in adult patients

BACKGROUND AND AIM OF THE STUDY

The study aim was to define the long-term outcome of pulmonary balloon valvulotomy (PBV) in adult patients.

METHODS

PBV was performed in 87 patients (46 females, 41 males; mean age 23+/-9 years; range: 15-54 years) with congenital pulmonary valve stenosis (PS). Intermediate follow up catheterization (mean 14.6+/-5.0; range: 6-24 months) was performed after PBV in 53 patients. Clinical and Doppler echocardiography examinations were carried out annually in 82 patients (mean 8.0+/-3.9; range: 2-15 years).

RESULTS

There were no immediate or late deaths. The mean catheter peak pulmonary gradient (PG) before and immediately after PBV, and at intermediate follow up was 105+/-39, 34+/-26 (p <0.0001) and 17+/-14 (p <0.0001) mmHg, respectively. The corresponding values for right ventricular (RV) pressure were 125+/-38, 59+/-21 (p <0.0001) and 42+/-12 (p <0.0001) mmHg, respectively. The infundibular gradients immediately after PBV and at intermediate follow up were 31+/-23 and 14+/-9 mmHg (p <0.0001), whilst cardiac index improved from 2.68+/-0.73 to 3.1+/-0.4 l/min/m2 (p <0.05) at intermediate follow up. Doppler PG before PBV and at intermediate and long-term follow up were 91+/-33 (range 36-200) mmHg, 28+/-12 (range 10-60) mmHg (p <0.0001) and 26+/-11 mmHg (p = 0.2), respectively. New pulmonary regurgitation (PR) was noted in 21 patients (25%) after PBV. Five patients (6%) with a suboptimal result (immediate valve gradient > or =30 mmHg) developed restenosis and underwent repeat valvulotomy 6-12 months later using a larger balloon, and with satisfactory outcome. Moderate to severe tricuspid regurgitation (TR) in seven patients regressed after PBV.

CONCLUSION

The long-term results of PBV in adults are excellent, with regression of concomitant, severe infundibular stenosis and/or severe TR. Hence, PBV should be considered as the treatment of choice for adult patients with PS.

Anaemia among Egyptian adolescents: prevalence and determinants

We aimed to estimate the nationwide prevalence of anaemia among adolescents in Egypt and to study possible risk factors. A cross-sectional approach was used. Blood samples were collected from 1980 adolescents for haemoglobin estimation. The overall prevalence of anaemia was 46.6%, most of which was mild or moderate, with severe cases in less than 1.0% of the sample. Gender difference was almost nonexistent. A significant inverse relationship was observed between the level of anaemia and age [especially among boys], socioeconomic level and educational level. Anaemia was more prevalent in rural areas and in Upper [southern] Egypt. Anaemia is a major public health problem among Egyptian adolescents and wide-scale public health education is warranted.

Anaemia among Egyptian adolescents: prevalence and determinants

We aimed to estimate the nationwide prevalence of anaemia among adolescents in Egypt and to study possible risk factors. A cross-sectional approach was used. Blood samples were collected from 1980 adolescents for haemoglobin estimation. The overall prevalence of anaemia was 46.6%, most of which was mild or moderate, with severe cases in less than 1.0% of the sample. Gender difference was almost nonexistent. A significant inverse relationship was observed between the level of anaemia and age (especially among boys), socioeconomic level and educational level. Anaemia was more prevalent in rural areas and in Upper (southern) Egypt. Anaemia is a major public health problem among Egyptian adolescents and wide-scale public health education is warranted.

Double-chambered right ventricle in 73 patients: spectrum of the disease and surgical results of transatrial repair

OBJECTIVE

To review the spectrum of double-chambered right ventricle (DCRV) and the outcome of surgical repair in patients diagnosed between February 1988 and March 1999.

DESIGN

The charts of patients with DCRV were studied.

SETTING

Tertiary care hospital.

PATIENTS AND METHODS

A total of 73 patients were identified. Sixty-nine underwent surgical repair, while four are awaiting surgery. The repair was through a transatrial approach in 61 patients, while in eight an additional ventriculotomy was performed.

MAIN RESULTS

An associated ventricular septal defect (VSD) was present in 56 of 73 patients (77%). These patients were significantly younger (P<0.05) than the 17 patients without a VSD. Among patients with a VSD, the 31 requiring patch closure were significantly younger than the 25 patients having direct closure. Five older patients among those with intact septum had impaired right ventricular (RV) function as well as higher intraventricular gradients. At surgery the intraventricular obstruction was relieved by myomectomy. There was no hospital or late mortality. Following surgery, at a mean follow-up of 13.6 months, no increase in the intraventricular gradient was detected by Doppler echocardiography.

CONCLUSIONS

The development of DCRV is associated with VSD in early life. The probability of the presence of a VSD decreases with age. The disease is progressive, resulting in increased intracavitary gradient within the RV and in RV impairment if it is not treated in a timely fashion. Transatrial repair is safe with excellent midterm results. In the presence of high gradients within the RV, a ventriculotomy may be necessary to obtain acceptable results.

Changes of management in a patient with double outlet left ventricle

Double outlet left ventricle is an extremely rare anomaly. Until recently, the diagnosis was usually established by angiography or at postmortem. There are only a few reports describing the echocardiographic findings in this lesion, and as far as we know, no report showing the anatomy as well as the velocity and pattern of flow by color Doppler echocardiography. The patient reported here underwent surgery at the age of four years, when an aortic homograft was placed between the right ventricle and the pulmonary trunk. This biventricular repair had to be changed into a Fontan-type procedure, 15 years later since the hypoplastic right ventricle did not grow adequately.

[Interventions in congenital heart disease and their sequelae in adults]

The advancements of cardiac surgery over the last decades led to larger numbers of patients with operated congenital heart diseases surviving into adulthood. In Germany it is estimated that over 120,000 adults have operated congenital heart diseases. Five to 7% of them will need yearly hospital admissions. Interventional procedures are additional tools used to treat these patients with various sequelae or residua (Table 1). In the following review we concentrate on 2 different interventional procedures: dilatation and stent implantations for treatment of stenosis and the different devices used for the closure of shunt lesions. For congenital valvular pulmonary stenosis, balloon dilatation is the therapy of choice regardless the age of the patient. Stent implantation for the treatment of peripheral pulmonary stenosis (e.g., after previous systemic pulmonary shunts) can decrease the need for redo surgery, which is accompanied with increased risk. Stent implantations proved also to be useful to treat stenoses after Mustard patch in patients with transposition of the great arteries, after Fontan procedures or dealing with the rare pulmonary venous stenosis. In contrast, dilatation of bioprosthesis and conduit stenosis are not promising. Balloon dilatation of valvular aortic stenosis is an accepted therapy in childhood up to adolescents. Table 2 compares a surgical series including many infants with critical aortic stenosis with a series of balloon dilatation in children and another one in adults regarding lethality, complications, and results. Table 3 illustrates the immediate and late results of balloon dilatation of aortic coarctation in 3 different studies. The high recurrence rate in infants made clinicians refrain from taking this age group for balloon dilatation. In children and adult patients, good results are reported (75% reduction of gradients). The complication rate is low (2.3 to 3.3%) and aneurysm formation rate seldom (1 to 7%). Stenosed aorto-pulmonary collaterals will rarely need balloon dilatation. Surgical closure of atrial septal defect is a low risk procedure with a very low rate of residual shunts (2%). Of the 5 available devices for transcatheter closure of atrial septal defect Type II, only 2 occluders are in use in Germany, the Clamshell and the Amplatzer device. The largest clinical studies of the different systems, their efficacy, complications and residual shunt rate are presented in Table 4. For the deployment of these occluders a TEE is always needed. There are many more systems in clinical use to close the patent arterial duct (PDA) (Table 5). The Ivalon plug as well as the Rashkind device have probably only historical value. Different types of coils (Gianturco, Cook detachable, PFM) are now in use worldwide. The reason for their widespread use, besides their easy application, is the fact that most coils are relatively cheap and need only small sheaths for deployment. Their further evaluation identified a residual shunt rate of 5% as well as a number of complications (embolization, hemolysis, stenosis of the left pulmonary artery) in 0 to 6%. For the large PDA the Amplatzer device has recently been introduced. An additional indication for the use of the different occluding devices are aorto-pulmonary collaterals, venovenous fistulae, pulmonary or coronary artery fistulae. Aorto-pulmonary collaterals are often associated with complex cardiac lesions and occasionally appear after palliative procedures. An excellent cooperation between adult and pediatric cardiologists is needed in order to offer the group of adults with congenital heart diseases an adequate and comprehensive management.

Long-term effects of balloon angioplasty on systemic hypertension in adolescent and adult patients with coarctation of the aorta

AIMS

To define the long-term effect of balloon angioplasty of aortic coarctation on hypertension, in adolescent and adult patients.

METHODS

Balloon angioplasty of discrete, native aortic coarctation was performed on 50 patients (34 male) aged 23+/-8 (mean+/-standard deviation) years. In 42 of these patients cardiac catheterization and angiography were repeated 1 year later, and on the basis of sphygmomanometric blood pressure determination at that time, they were divided into 31 patients (group A) with normalized blood pressure and 11 patients (group B) who still needed antihypertensive medication. Both groups were followed annually thereafter for 12-123 (66+/-37) months.

RESULTS

Coarctation gradient values before, immediately after and 1 year after angioplasty were 69+/-24 mmHg, 12+/-8 mmHg (P<0.001) and 7+/-6 mmHg. The corresponding systolic blood pressure values were 165+/-17 mmHg, 128+/-12 mmHg (P<0.001) and 115+/-10 mmHg (P<0.001) in group A; 182+/-21 mmHg, 141+/-24 mmHg (P<0.001) and 134+/-18 mmHg (P<0.001) in group B. Echocardiographic left ventricular mass index before angioplasty and at follow-up was 130+/-31 g x m-2 and 105+/-23 g x m-2 in group A; 157+/-38 g x m-2 and 132+/-35 g x m-2 in group B (P<0.001 for both comparisons).

CONCLUSION

Normalization of blood pressure without medication occurred in 74% of patients after angioplasty for aortic coarctation, with subsequent long-term regression of left ventricular hypertrophy. In comparison to reported surgical results, balloon angioplasty should be considered as first line treatment for native, discrete aortic coarctation in adolescent and adult patients.

Phentolamine improves clinical outcome after balloon valvoplasty in neonates with severe pulmonary stenosis

Two neonates with severe pulmonary stenosis deteriorated immediately after successful balloon valvoplasty as a result of increased infundibular obstruction. They were treated with beta-adrenoceptor blockers and intravascular expansion with limited success. Phentolamine was then given, resulting in dramatic improvement. The children could be weaned from the ventilator within hours of starting this new therapeutic modality.

The role of selenium deficiency in dilated cardiomyopathy in Saudi Arabia

BACKGROUND

Selenium deficiency is implicated in the etiology of endemic juvenile dilated cardiomyopathy in China, and in sporadic cases in other countries. The aim of this study was to evaluate the role of selenium deficiency in the pathophysiology of dilated cardiomyopathy in the Saudi Arabian population.

PATIENTS AND METHODS

Plasma and urine selenium concentrations from 72 Saudi patients with confirmed dilated cardiomyopathy were compared with corresponding values from 70 control subjects of the same national origin who had normal ventricular function.

RESULTS

Plasma and urine selenium concentrations (mean+/-SD) were 1.347plusmn;0.45 and 0.49+/-0.37 micromol/L, respectively, for the patient group, and 1.32+/-0.41 and 0.60+/-0.41 micromol/L, respectively, for the control group. The differences in the values between the two groups were statistically insignificant.

CONCLUSION

In the Saudi population, dilated cardiomyopathy is not caused by selenium deficiency.

Results of three to 10 year follow up of balloon dilatation of the pulmonary valve

BACKGROUND

The results of immediate and short term follow up of balloon dilatation of the pulmonary valve have been well documented, but there is limited information on long term follow up.

OBJECTIVE

To evaluate the results of three to 10 year follow up of balloon dilatation of the pulmonary valve in children and adolescents.

SETTING

Tertiary care centre/university hospital.

DESIGN

Retrospective study.

METHODS AND RESULTS

85 patients (aged between 1 day and 20 years, mean (SD) 7.0 (6.4) years) underwent balloon dilatation of the pulmonary valve during an 11 year period ending August 1994. There was a resultant reduction in the peak to peak gradient from 87 (38) to 26 (22) mm Hg. Immediate surgical intervention was not required. Residual gradients of 29 (17) mm Hg were measured by catheterisation (n = 47) and echo Doppler (n = 82) at intermediate term follow up (two years). When individual results were scrutinised, nine of 82 patients had restenosis, defined as a peak gradient of 50 mm Hg or more. Seven of these patients underwent repeat balloon dilatation of the pulmonary valve: peak gradients were reduced from 89 (40) to 38 (20) mm Hg. Clinical evaluation and echo Doppler data of 80 patients showed that residual peak instantaneous Doppler gradients were 17 (15) mm Hg at long term follow up (three to 10 years, median seven), with evidence for late restenosis in one patient (1.3%). Surgical intervention was necessary to relieve fixed infundibular stenosis in three patients and supravalvar pulmonary stenosis in one. Repeat balloon dilatation was performed to relieve restenosis in two patients. Actuarial reintervention free rates at one, two, five, and 10 years were 94%, 89%, 88%, and 84%, respectively. Pulmonary valve regurgitation was noted in 70 of 80 patients at late follow up, but neither right ventricular dilatation nor paradoxical interventricular septal motion developed.

CONCLUSIONS

The results of late follow up of balloon dilatation of the pulmonary valve are excellent. Repeat balloon dilatation was performed in 11% of patients and surgical intervention for subvalvlar or supravalvar stenosis in 5%. Most patients had mild residual pulmonary regurgitation but right ventricular volume overload was not required. Balloon dilatation is the treatment of choice in the management of moderate to severe stenosis of the pulmonary valve. Further follow up studies should be undertaken to evaluate the significance of residual pulmonary regurgitation.

Reconstruction of supravalvar aortic stenosis with autologous pulmonary artery

Use of autologous tissue in corrective cardiac operations offers many advantages including the potential for growth. We report a surgical technique using autologous pulmonary artery in the repair of supravalvar aortic stenosis in a 6-year-old child. At 30 months' follow-up, the pulmonary arterial tissue shows no evidence of calcification or dilatation and appears to be growing with the aorta.

Clinical results and radiographic appearance of the Rashkind double umbrella device in patients with occlusion of the ductus arteriosus

BACKGROUND

The Rashkind double umbrella device for patent arterial duct occlusion has been used in many patients. Its radiographic appearance has not been sufficiently described.

OBJECTIVE

To present the varying radiographic appearances of the Rashkind double umbrella device on the chest X-ray.

MATERIALS AND METHODS

The chest radiographs of 69 patients (median age 60 months; median weight 17 kg), who underwent closure of their patent arterial duct between March 1990 and August 1994, were reviewed. The following parameters were evaluated: 1) the size of the heart (cardio-thoracic ratio) and pulmonary vessels, 2) the position of the device in AP/PA and lateral projections. The results of occlusion of the patent arterial duct were also reviewed.

RESULTS

Sixty-two of 69 (90 %) patients had complete occlusion after a follow-up between 2 months and 3(1)/2 years. The cardio-thoracic ratio showed significant reduction at follow-up (P < 0.001). The two different size devices could be well differentiated in the AP and the lateral projection. In 14 patients (20 %) the device was in an asymmetrical position. There was no significant correlation between position of the device and success of occlusion in our material.

CONCLUSION

Complete occlusion of the arterial duct using Rashkind double umbrella devices can be achieved in 90 % of our population. In 20 % the device will have an asymmetrical position. There is no correlation between asymmetrical position of the device in the chest radiograph and residual shunting.

One- to ten-year follow-up results of balloon angioplasty of native coarctation of the aorta in adolescents and adults

OBJECTIVES

We attempted to evaluate the role of balloon angioplasty in the treatment of discrete coarctation of the aorta in adolescents and adults, with special emphasis on long-term results.

BACKGROUND

Controversy persists over the use of balloon dilation for the treatment of native coarctation of the aorta.

METHODS

Between July 1986 and January 1997, 43 consecutive adolescent and adult patients with discrete coarctation of the aorta underwent balloon angioplasty. One- to 10-year follow-up data of 37 patients, including results of cardiac catheterization and magnetic resonance imaging (MRI), form the basis of this study.

RESULTS

No early or late deaths occurred. Balloon angioplasty produced a reduction in the peak to peak coarctation gradient from a mean +/- SD of 69 +/- 24 mm Hg (95% confidence interval [CI] 61 to 76) to 12 +/- 8 mm Hg (95% CI 10 to 14.8) (p < 0.001). Follow-up catheterization 12 months later (37 patients) revealed a residual gradient of 6.7 +/- 6 mm Hg (95% CI 4.6 to 8.9); 3 (7%) of 43 patients had suboptimal results with development of recoarctation, defined as peak gradient >20 mm Hg, with successful repeat angioplasty. A small aneurysm developed at the site of dilation in 3 (7%) of the 43 patients. MRI follow-up data 1 to 10.8 years (mean 5.2 +/- 2.7) after angioplasty (37 patients) revealed no new aneurysm or appreciable change in the size of the preexisting aneurysm in the three patients. The blood pressure had normalized without medication in 27 (73%) of 37 patients at follow-up examination.

CONCLUSIONS

Balloon angioplasty is safe and effective and should be considered a viable alternative to operation for treatment of discrete coarctation of the aorta in adolescents and adults.

Pulmonary artery augmentation with autologous aortic tissue

OBJECTIVE

To assess durability and viability of autologous aortic tissue used to augment severe branch pulmonary artery stenosis with a novice surgical technique.

PATIENTS AND METHODS

Seven patients underwent corrective surgery for complex cyanotic congenital heart disease. Their age ranged from 3-6 years, and their weight 11-17.4 kg. All had concomitant branch pulmonary artery stenosis repaired utilizing an autologous patch, harvested from the patient's own aorta by excising a ring and opening it to form the patch. The aorta is reconstructed directly by end to end anastomosis.

RESULTS

One patient died in hospital. Another patient died at 18 months at home. The surviving five patients have remained well in the follow up period of mean 31 months (range 10-52). All patients were restudied by follow up echocardiography and remain with no evidence of the aortic autograft tissue calcification or stenosis. The reconstructed aorta showed no stenosis at the site of anastomosis.

CONCLUSION

The intermediate term results of this novice surgical technique appear encouraging and justify the technique. However, longer follow up will be required to confirm the continued growth of this patch material.

Lack of evidence for connexin 43 gene mutations in human autosomal recessive lateralization defects

Heterotaxy is the failure of the developing embryo to establish normal left-right asymmetry, which is often associated with multiple malformations. Previous studies have identified different mutations in the cytoplasmic tail of the connexin 43 (cx 43) gene in six patients from a series of six sporadic cases with defects of laterality and severe heart malformations. These cases showed that of the genes involved in lateralization defects with autosomal recessive transmission, cx 43 was the most important. This result was challenged by two different teams, which, on sequencing only the carboxyl terminal end of the cx 43 gene in 30 patients, found no mutations. To assess the responsibility of the cx 43 gene in human autosomal recessive lateralization defects, we tested its involvement in a selected group of 25 patients (19 familial cases) with a wide variety of lateralization defects and cardiovascular malformations. The whole coding sequence and direct flanking sequences were screened for mutations, both by single strand conformation analysis and direct fluorescent sequencing. We could only detect a single base pair insertion in the 3' untranslated region of one patient. To test the possibility of mutations in other parts of the cx 43 gene, the gene was located onto the physical map of chromosome 6, and flanking polymorphic markers were genotyped. Haplotype analysis excluded the cx 43 gene locus in nearly all of the familial cases of lateralization defects. Thus, our results do not support the suggestion that this gene is implicated in human autosomal recessive lateralization defects.

Follow-up results of balloon aortic valvuloplasty in children with special reference to causes of late aortic insufficiency

The purpose of this study was to report on 3- to 9-year follow-up data after balloon aortic valvuloplasty in children and to investigate causes of aortic insufficiency at late follow-up. Although the immediate and short-term results of balloon aortic valvuloplasty have been well documented, little information is available on long-term follow-up results. During a 7.3-year period ending December 1992, 26 young patients, aged 6 weeks to 20 years, underwent balloon aortic valvuloplasty with resultant reduction of peak-to-peak aortic valvar gradient from 71 +/- 20 (mean +/- SD) to 25 +/- 12 mm Hg (p < 0.001). None required immediate surgical intervention. At intermediate-term follow-up, 6 (23%) of 26 had restenosis develop and underwent surgical (4 patients) or repeat balloon valvuloplasty (2 patients). Clinical and echo-Doppler data 3 to 9 years (median 6 years) after balloon valvuloplasty revealed residual peak instantaneous Doppler gradients of 26 +/- 13 mm Hg (p < 0.001), without restenosis beyond what was observed at intermediate-term follow-up. Aortic insufficiency progressed in seven patients. However, none required intervention. Actuarial intervention-free rates at 1, 2, 5, and 9 years were 80%, 76%, 76%, and 76%, respectively. Logistic regression analysis suggested that the degree of Doppler-quantitated aortic insufficiency 1 day after valvuloplasty predicts persistent aortic insufficiency at late follow-up. These data indicate that immediately successful balloon aortic valvuloplasty in children yields a residual gradient of < or = 36 mm Hg at a median of 6 years of follow-up in most patients and an intervention-free rate at 9 years of 76%. Restenosis occurs but can be treated with a repeat intervention with good results. Aortic insufficiency remains stable and does not appear to require intervention, at least during the first decade after balloon dilatation.

Problems encountered during introduction of Gianturco coils for transcatheter occlusion of the patent arterial duct

OBJECTIVE

To define the problems encountered during transcatheter occlusion of the patent arterial duct using Gianturco coils.

METHODS

Between January 1994 and November 1995, 93 patients were admitted in whom it was intended to occlude the patent arterial duct using Gianturco coils. Anterograde transcatheter coil occlusion was performed via the femoral vein in 81 patients. In the remaining 12 the procedure was done via the femoral artery.

RESULTS

Coils were implanted successfully in 82/93 (88%) patients. In 11 patients the procedure was a failure. In 19/93 patients (20%), inadvertent embolization of the coil occurred. The coils were retrieved in all except one patient. In 17 of these patients, new coils were then reimplanted successfully. Doppler echocardiography after the procedure showed that in 9/82 (11%) patients the left pulmonary artery Doppler peak velocity exceeded 1.5 m.s-1 (mean 1.2 m.s-1) raising concern about left pulmonary artery branch stenosis. The complete occlusion rate at discharge from hospital was 72/82 (88%). Follow-up ranges from 1 day to 14 months (mean 2/12 months) in the 82 patients in whom successful deployment of coils was possible. In two patients, the arterial duct became occluded at follow-up. One additional patient had complete occlusion after reocclusion using another coil. Thus, after short-term follow-up a total of 75/82 patients (91.4%) have a completely occluded arterial duct after coil implantation.

CONCLUSION

Transcatheter occlusion of the patent arterial duct using Gianturco coils is an effective and safe technique. In the learning curve there is a relatively high rate of inadvertent embolization, but the coils can be retrieved in the vast majority of patients. The complication rate is offset by the high early occlusion rate and the inexpensiveness of the procedure.

The role of surgical ligation of patent ductus arteriosus in the era of the Rashkind device

BACKGROUND

The role of surgery in managing patent ductus arteriosus (PDA) was studied in the era of the Rashkind double-umbrella device.

METHODS

All 354 patients with PDA referred to our center in a 5-year period were included in this report. Of the 354 patients, 236 underwent cardiac catheterization with the intent of transcatheter PDA closure, and 118 had surgical intervention.

RESULTS

In 46 (19.5%) of the 236 patients having cardiac catheterization, the procedure either was abandoned or failed. Color Doppler echocardiography demonstrated total occlusion of the ductus after 24 hours in 97 patients (41%) in the cardiac catheterization group. An additional 20 patients had no residual leaks at follow-up. Twenty other patients underwent reocclusion because of a residual shunt. Thus, of the 236 patients, 137 (58%) had successful complete closure of the PDA. Surgical PDA ligation was performed in 118 patients as the initial procedure and in 26 of the 46 patients in whom transcatheter closure was abandoned. If the remaining 20 patients in whom transcatheter closure failed are added to the 144 patients who underwent PDA ligation, the percentage having surgical intervention versus transcatheter occlusion is higher than 46%.

CONCLUSIONS

Our data suggest that surgery plays a major role in the management of patients with PDA despite the advent of new interventional catheterization techniques.

Closure of residual leak after umbrella occlusion of the patent arterial duct, using Gianturco coils

Residual leak after transcatheter occlusion of the patent arterial duct (PDA) using the Rashkind double umbrella technique is a well documented problem. At our institution, there is a 15% incidence of persistent residual leak after 12 months. Since September 1994, 15 patients have undergone successful occlusion of the residual leak using single or multiple Gianturco coils. The median age of the patients was 48 months (range: 12-354 months). The median fluoroscopy time was 11 min (range: 4-14). There were no complications and no embolization of the coils. Eleven patients had total occlusion demonstrated on angiography 5-10 min after coil occlusion. A further three patients were demonstrated on colour Doppler echocardiography to have no residual leak before discharge the same day-despite a small leak on angiography. Only one of 15 patients had a small residual leak at the time of hospital discharge and this was finally occluded 1 year later with another coil. Coil occlusion of a residual leak on the umbrella device is effective and a safe and reliable procedure which appears to be an improvement on using a second umbrella device.

Feasibility and effectiveness of repeated balloon dilatation of restenosed congenital obstructions after previous balloon valvuloplasty/angioplasty

Balloon dilatation of congenital stenotic lesions of the heart and great vessels has been used for more than a decade. Varying incidence of residual obstruction or recurrence, hereafter referred to as restenosis, has been observed at follow-up. The purpose of this study was to evaluate the feasibility and effectiveness of repeated balloon dilatation of restenosed lesions after previous balloon dilatation for pulmonic (PS) and aortic (AS) stenosis and native aortic coarctation (AC). Neonates, infants, and children (n = 178) underwent balloon valvoplasty/angioplasty with reduction (p < 0.001) or peak-to-peak systolic pressure gradients from 91 +/- 41 (mean +/- SD) mm Hg to 25 +/- 19 mm Hg, from 70 +/- 20 mm Hg to 26 +/- 12 mm Hg, and from 48 +/- 17 mm Hg, to 11 +/- 9 mm Hg in patients with PS, AS, and AC, respectively. Repeated catheterization or echo-Doppler studies or both were performed from 3 months to 5 years after initial balloon dilatation. Residual gradients at follow-up were 26 +/- 26 mm Hg, 34 +/- 20 mm Hg, and 16 +/- 15 mm Hg, respectively, for PS, AS, and AC and remained significantly lower (p < 0.01) compared with gradients before the balloon dilatation. However, when results of individual patients were scrutinized, 9 (11%) of 80 patients with PS, 6 (23%) of 26 patients with AS, and 16 (27%) of 60 patients with AC had restenosis, on the basis of standard criteria. Repeated balloon dilatation was performed with reduction (p < 0.05 to < 0.001) of peak-to-peak gradients from 89 +/- 40 mm Hg to 38 +/- 20 mm Hg in 9 patients with PS, from 77 mm Hg to 13 mm Hg and 66 mm Hg to 6 mm Hg, respectively, in 2 patients with AS, and from 38 +/- 11 mm Hg to 10 +/- 6 mm Hg in 12 patients with AC. Echo-Doppler studies, 2 to 6.5 years after repeated balloon dilatation, indicated excellent results, with residual peak instantaneous Doppler gradients of 24 +/- 13 mm Hg in PS, 43 +/- 20 mm Hg in AS, and 11 +/- 6 mm Hg in AC groups, respectively. This improvement is irrespective of the cause of restenosis after initial balloon valvuloplasty/angioplasty. From this experience, we conclude that repeated balloon dilatation is feasible and effective in relieving restenosis after initial balloon valvuloplasty/angioplasty.

Thrombosis on the Rashkind double umbrella device: a complication of PDA occlusion

A 3-year-old child with a patent arterial duct underwent percutaneous transcatheter occlusion using Rashkind's "double umbrella" technique. The procedure, using a 17 mm device, was uncomplicated. An echocardiogram done 6 hr later showed a mobile 5 x 3 mm thrombus on the pulmonary aspect of the device. The thrombus resolved after 24 hr of intravenous heparin.

Anterograde transcatheter occlusion of the patent ductus arteriosus with Gianturco coils--a new, effective and inexpensive technique

OBJECTIVE

To report the use of Gianturco coils in non-surgical closure of patent ductus arteriosus (PDA).

DESIGN

Retrospective review of patient data.

SETTING

Two specialist paediatric cardiology units in Riyadh, Saudi Arabia, and Cape Town, South Africa.

PATIENTS

Thirty children (median age 36 months, weight 12.5 kg) and one adult (24 years old) with PDA underwent attempted transcatheter closure of the duct between August 1994 and February 1995.

OUTCOME MEASURES

Assessment of duct closure as measured angiographically or with colour flow Doppler techniques after insertion of a Gianturco coil or coils.

RESULTS

Total occlusion was achieved in 90% of patients. In 2 patients accidental embolisation of the coil occurred during the procedure. The coils were easily retrieved with a snare retrieval device. The median diameter of PDA occluded was 2.5 mm. Between 1 and 6 coils were used to achieve occlusion. The median procedure time was 79 minutes. Seventy-nine per cent of patients in Riyadh were handled as day cases.

CONCLUSION

Anterograde transcatheter occlusion of a small to moderate PDA with Gianturco coils is safe and effective. The technique is considerably less expensive than the Rashkind double umbrella.

Stent implantation for relief of pulmonary artery stenosis: immediate and short-term results

Our objective was to assess the immediate and short-term results of stent implantation to relieve pulmonary artery stenosis (PAS). Thirty-seven patients underwent an attempt at stent implantation at a median age of 7.0 years (range, 0.8-31.4 years) and a median weight of 20.5 kg (range, 7.4-85 kg). Twenty-two patients had previous tetralogy of Fallot repair. A total of 55 stents were implanted successfully in 36 patients. The peak systolic gradient across the stenotic segment decreased from a mean of 43 +/- 20.4 mmHg prestent to 13 +/- 13.9 mmHg (P < 0.001) poststent. The diameter of the narrowest segment increased from a mean of 4.8 +/- 1.6 mm to 10.5 +/- 2.6 mm (P < 0.001). The right ventricular-to-aortic mean systolic pressure ratio decreased from 0.74 +/- 0.2 to 0.52 +/- 0.19 (P < 0.001). Complications included balloon rupture prior to full stent expansion in 4 patients (in 2 patients the stent was positioned in the superior vena cava, and in 2 in the inferior vena cava), distal migration of a stent which was successfully retrieved at surgery 1 mo later in 1 patient, and tethering of the stent to the balloon requiring surgical removal in 1 patient. One patient died several hours after stent placement. Sixteen patients underwent repeat catheterization at a mean follow-up interval of 0.9 +/- 0.5 years (range, 0.2-2.0 years). The mean gradient across the stent for these 16 patients was 26.7 +/- 19.8 mmHg, and there was no change in the mean diameter (9.4 +/- 3.2 mm). Two patients developed stenosis related to neointimal proliferation at the stent site which was redilated successfully. In conclusion, stent implantation is generally safe and effective in relieving PAS.

Sympathetic activity in children undergoing balloon valvuloplasty of pulmonary stenosis

We studied the influence of balloon valvuloplasty on alpha- and beta-adrenoceptor densities, plasma catecholamine, and cAMP levels in children and infants with pulmonary stenosis before and 10 min after balloon dilatation, employing as controls children undergoing transcatheter occlusion of patent ductus arteriosus (PDA) with Qp/Qs ratio < 1.5. In the PDA group, the alpha-adrenoceptor density (Bmax) was 3.75 +/- 0.72 fmol/10(7) cells (n = 15) before occlusion and remained unchanged at 3.35 +/- 0.47 fmol 10 min thereafter. In the pulmonary stenosis patients (n = 31), the receptor density was 59% higher (p < 0.05) before, and decreased to PDA levels 10 min after, the procedure. The control beta-adrenoceptor density was 64.8 +/- 11.0 fmol/10(6) cells before, and 71.2 +/- 13.2 fmol 10 min after, occlusion. In the study group, the density was 23% lower (p < 0.07) and increased to the PDA levels 10 min after the dilatation. Compared with the PDA, pre- and postdilatation plasma norepinephrine levels were not significantly changed; epinephrine was slightly elevated before, but increased by 73% after, dilatation; dopamine was 80% (p < 0.05); and cAMP was 37% higher before, and remained elevated at 70 and 23% above the PDA values after, the procedure. Accordingly, alpha-adrenoceptor density is significantly elevated in children with pulmonary stenosis and decreases significantly immediately after balloon valvuloplasty. On the other hand, beta-adrenoceptor density is attenuated and increases toward normal levels after the procedure. The immediate reversal of the receptor levels after balloon valvuloplasty suggests that this procedure exerts acute effects on the sympathetic functional level in this disease.

The significance of children's age in estimating the effect of maternal time use on children's well-being

The women's initiative launched by the United Nations Decade for Women has sparked unresolved controversy over the consequences of mothers' increased participation in economically productive activities on children's well-being. Clearly, in many developing countries, poor mothers face stringent time constraints requiring trade-offs in time allocated to various activities, including child caregiving. However, the impact of these trade-offs on children's well-being remains unclear. The effect of maternal time use on children's nutrition and health status requires more rigorous examination. In particular, the role of children's age in this relationship is critical. Although children's requirement for maternal care varies with factors such as their age (a proxy for stage of psychobiological and sociocultural development), season of year and family size and structure, children's age has not been highlighted in the debate or in the relevant research. This paper documents children's age as a critical factor in the relationship between maternal patterns of time use and the well-being of children 18-30 months of age in peri-urban Egypt. It describes differences in maternal patterns of daily time use according to children's age and illustrates the differential associations between maternal daily activity patterns and children's well-being by children's age. Quantitative data collected on 161 mother-toddler pairs included information on maternal daily time allocation, children's dietary energy intake and diarrheal morbidity, maternal hemoglobin, and household and individual sociodemographics. Data were stratified by children's age at 24 months and were analyzed cross-sectionally using multiple linear and logistic regression. Results indicated that the age of two is critical in Kalama. At this age, toddlers begin to receive less time-intensive care freeing mothers for economic and self production. With respect to children's well-being prior to age two, frequency of feeding was positively related to their energy intake and more time spent in household sanitation activities reduced children's risk of diarrhea (during the diarrhea season). After two years of age, the maternal behaviors measured did not affect children's energy intake; however, children's diarrheal risk was reduced (during the diarrhea season) when mothers held them more and allocated more time to household sanitation year-round. We recommend that other investigators carefully examine the relationships between children's well-being according to developmentally-defined child age intervals and maternal patterns of time use. Results will help to resolve concern over the effect of maternal participation in economically productive activities on children's well-being.

Transcatheter closure of the patent ductus arteriosus: comparison between the Rashkind occluder device and the anterograde Gianturco coils technique

Thirty-five patients (mean age 43.7 months, mean weight 13 kg) underwent anterograde patent ductus arteriosus (PDA) occlusion with Gianturco coils (coil group). These patients were compared with 35 age- and weight-matched patients who underwent closure of their PDA with the Rashkind umbrella device (device group). The mean PDA diameter at its narrowest point was 2.8 mm in the coil group and 2.7 mm in the device group. There was immediate closure angiographically in 20 (57%) of 35 in the coil group compared with 9 (26%) of 35 for the device group. Color flow mapping before discharge revealed complete closure in 30 (86%) of 35 in the coil group compared with 18 (51%) of 35 in the device group (chi square = 9.5455, p < 0.005). Mean fluoroscopy time was 18.5 minutes (median 13.5 minutes) and 14.7 minutes (median 13 minutes) for the coil and device, respectively. Four coils and one device embolized down the pulmonary artery; all were successfully retrieved in the catheterization lab. Coil closure of the small to moderate PDA is safe and effective. It is more effective in achieving immediate closure than the Rashkind device. More clinical trials with the coil technique are warranted to establish the long-term results of this technique.

Five- to nine-year follow-up results of balloon angioplasty of native aortic coarctation in infants and children

OBJECTIVES

To evaluate the usefulness of balloon angioplasty for relief of native aortic coarctation, we reviewed our experience with this procedure, with special emphasis on follow-up results.

BACKGROUND

Controversy exists with regard to the role of balloon angioplasty in the treatment of native aortic coarctation.

METHODS

During an 8.7-year period ending September 1993, 67 neonates, infants and children underwent balloon angioplasty for native aortic coarctation. A retrospective review of this experience with emphasis on long-term follow-up forms the basis of this study.

RESULTS

Balloon angioplasty produced a reduction in the peak-to-peak coarctation gradient from 46 +/- 17 (mean +/- SD) to 11 +/- 9 mm Hg (p < 0.001). No patient required immediate surgical intervention. At intermediate-term follow-up (14 +/- 11 months), catheterization (58 patients) and blood pressure (2 patients) data revealed a residual gradient of 16 +/- 15 mm Hg (p > 0.1). When individual results were scrutinized, 15 (25%) of 60 had recoarctation, defined as peak gradient > 20 mm Hg. Recoarctation was higher (p < 0.01) in neonates (5 [83%] of 6) and infants (7 [39%] of 18) than in children (3 [8%] of 36), respectively. Two infants in our early experience had surgical resection with excellent results. Three patients had no discrete narrowing but had normal arm blood pressure and had no intervention. The remaining 10 patients had repeat balloon angioplasty with reduction in peak gradient from 52 +/- 13 to 9 +/= 8 mm Hg (p < 0.001). Reexamination 31 +/- 18 months after repeat angioplasty revealed a residual gradient of 3 to 19 mm Hg (mean 11 +/- 6). Three (5%) of 58 patients who underwent follow-up angiography developed an aneurysm. Detailed evaluation of the femoral artery performed in 51 (88%) of 58 patients at follow-up catheterization revealed patency of the femoral artery in 44 (86%) of 51 patients. Femoral artery occlusion, complete in three (6%) and partial in four (8%), was observed, but all had excellent collateral flow. Blood pressure, echocardiography-Doppler ultrasound and repeat angiographic or magnetic resonance imaging data 5 to 9 years after angioplasty revealed no new aneurysms and minimal (2%) late recoarctation.

CONCLUSIONS

On the basis of these data, it is concluded that balloon angioplasty is safe and effective in the treatment of native aortic coarctation; significant incidence of recoarctation is seen in neonates and infants; repeat balloon angioplasty for recoarctation is feasible and effective; and the time has come to consider balloon angioplasty as a therapeutic procedure of choice for the treatment of native aortic coarctation.

Child feeding patterns in the Middle East

A diversity in infant feeding patterns exists throughout the Middle East. Wide variations in cultures, languages, ethnic background, religions and social practices should be taken into consideration, when designing programs to promote appropriate feeding practices. Strategies applied in one community might not be appropriate for another. In order to be effective, these should be incorporated into overall primary health care programs.

Regulation of sympathetic activity in children with various congenital heart diseases

We studied the alpha- and beta-adrenoceptor activity and catecholamine and cAMP levels in 112 children and infants admitted to the hospital for diagnostic or interventional catheterization of tetralogy of Fallot, ventricular septal defects with or without hypertension, pulmonary stenosis, coarctation of the aorta, and various complex cyanotic congenital cardiac diseases and compared them with 14 children undergoing transcatheter occlusion of patent ductus arteriosus with insignificant left-to-right-shunts. The mean total platelet alpha-adrenoceptor density of the study population was elevated by 73%. Both the increases in acyanotic (p < 0.05) and cyanotic (p < 0.005) patients as well as the difference between the two groups (p < 0.01) were significant. Based on the congenital disease classification, the elevation in receptor density was also significant in all groups of patients, except coarctation of the aorta. On the other hand, the mean lymphocyte beta-adrenoceptor density was attenuated by 27%, showing significant difference between the acyanotic and the patent ductus arteriosus groups, but none between acyanotic and cyanotic or cyanotic and the patent ductus arteriosus groups. Among the congenital groups, only the left-to-right shunts and the pulmonary stenosis group showed significant (p < 0.05) decrease in beta-adrenoceptor density, whereas the affinity of all the groups toward [125I]iodocyanopindolol was hardly influenced. The plasma levels of all three catecholamines, norepinephrine, epinephrine, and dopamine, were elevated, but cAMP remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Re-occlusion of residual leaks after transcatheter occlusion of patent ductus arteriosus

Between March 1990 and November 1993 175 patients underwent successful closure of patent ductus arteriosus using the Rashkind double umbrella device. Of those patients seen on follow up, 13 (9 female, 4 male) had a residual leak and were admitted for implantation of a second device alongside the first device. The interval between the procedures ranged from 6 to 22 months. The mean age at the first procedure was 73.9 months (range 24-204 months) and the mean weight was 18.9kg (range 8.4-64). The mean age at the second procedure was 86.9 months (30-213) and the mean weight was 21.4 kg (8.6-64). The first device was 17 mm in 11 patients and 12 mm in two. The second device was 17 mm in four patients and 12 mm in nine. Four patients required two 17 mm devices in total. There was no difference in the two procedures regarding the fluoroscopy time, procedure time, complications and length of hospital stay. The second procedure was uneventful; however, in one patient the residual ductus had to be dilated before successfully deploying a 12 mm device. Ten patients had immediate total occlusion and three had a trivial leak on echocardiography 24 h later. One of the three patients was found to have total occlusion on Doppler echocardiography 1 year later. The other patients are yet to be seen for follow-up. Hence a total occlusion rate was in 11/13 patients (85%).(ABSTRACT TRUNCATED AT 250 WORDS)

Reopening of an arterial duct after total occlusion with Rashkind's double umbrella device

Reopening of a previously totally occluded ductus arteriosus with the Rashkind umbrella device occurred in a 5-yr-old girl, a previously unreported occurrence. Total occlusion using a second device was successful. This report emphasizes the need for regular follow-up with color flow Doppler echocardiography to diagnose and exclude a residual ductus even when apparent early closure has occurred.

Mitral balloon valvotomy in children with Inoue balloon technique: immediate and intermediate-term result

Percutaneous mitral balloon valvotomy (PMV) using the Inoue balloon technique was attempted in 170 patients. Of these, 30 patients were children aged 10 to 18 years (mean 15.9 +/- 2.7 years). There were 16 female and 14 male patients. All were in sinus rhythm. The procedure was successful in 28 patients (93%). PMV was performed using 20 to 28 mm (mean 25 mm) diameter balloon catheters with an echo-Doppler guided stepwise mitral dilation technique. After PMV, the mean left atrial pressure decreased from 25 +/- 5 to 14 +/- 4 mm Hg (p < 0.001). The mean mitral valve gradient (MVG) decreased from 16 +/- 4 to 6 +/- 3 mm Hg (p < 0.001). The mitral valve area (MVA) by catheter increased from 0.7 +/- 0.2 to 1.7 +/- 0.5 cm2 (p < 0.001), and MVA as determined by echocardiography (2DE) increased from 0.8 +/- 0.1 to 1.9 +/- 0.3 cm2 (p < 0.01). There were no deaths or thromboembolic complications; cardiac tamponade developed in one patient, mild mitral regurgitation (MR) developed in three patients (10%) and increased by one grade from (1+ to 2+) in another two patients (8%). A small atrial septal defect (ASD) assessed by color flow mapping developed in seven patients (25%); 90% were closed at 3 months. The Doppler and 2DE MVAs were maintained at 1.8 +/- 0.4 cm2 at 17 months' mean follow-up; one patient developed restenosis. We conclude the PMV using the Inoue balloon catheter is safe and effective in the treatment of severe mitral stenosis in children, with a low complication rate.

Transesophageal echocardiography in children with cardiac assist

Transesophageal echocardiography (TEE) is an easy, relatively non-invasive method for evaluation of cardiac function and abnormalities during cardiac assist. We used 19 TEE in 9 children (age: 10 days-4 years, weight: 2.7-12 kg) with mechanically assisted circulation for postcardiotomy cardiogenic shock. TEE provided valuable information: (1) dislocation of the cannula causing hemodynamic instability could be easily diagnosed and corrected; (2) Doppler evaluation of valvular function revealed severe malfunction in two patients; (3) intracardiac thrombus could be clearly detected in two children with seriously impaired hemodynamics. These findings were followed by therapeutic interventions; (4) left-ventricular function before attempted weaning from cardiac assist was moderately reduced or normal in the survivors, but poor in the nonsurvivors. We conclude that TEE is a valuable contribution to improved patient management during cardiac assist.

Magnetic resonance imaging compared with angiography in the evaluation of intermediate-term result of coarctation balloon angioplasty

Between July 1986 and December 1990, 24 consecutive adult patients with native coarctation of the aorta underwent balloon dilatation. Their ages ranged from 15 to 55 (mean 25) years. Dissection of the aorta developed in one patient. The remaining 23 patients were restudied by catheterization and magnetic resonance imaging (MRI) 8 to 60 (mean 21) months after dilatation. Both studies were performed between 1 and 180 (mean 40) days of each other. The diameter of the aorta at the site of previous coarctation was measured on angiogram and MRI by two independent observers. The data were compared by means of linear regression analysis. The gradient across the previous coarctation site ranged from 0 to 20 (mean 7 +/- 7.3) mm Hg. The diameter of the aorta at the site of previous coarctation measured on angiogram was 13.7 +/- 3.7 mm and on MRI it measured 13.5 +/- 3.7 mm, with excellent correlation (r = 0.96, SEE = 0.92, p < 0.001). Two patients had small aneurysms 2 cm in diameter demonstrated by angiography and MRI, and two patients developed restenosis, diagnosed correctly by both cardiac catheterization and MRI. This study demonstrates that MRI provides excellent visualization of the anatomy of the aorta and is a good noninvasive method for follow-up of patients undergoing balloon coarctation angioplasty.

Transcatheter laser atrial septostomy in rabbits

The feasibility of percutaneous transluminal catheter-directed laser (Argon multiline 488/514 nm) atrial septostomy under echocardiographic guidance was studied in eight rabbits. In five animals the interatrial septum was exposed to laser energy for 30 s (n = 1) or for 10 s (n = 4) by using the continuous wave (cw) mode of irradiation. In the other three animals chopped mode of irradiation was applied for 10 s at 7 W. Echocardiography allowed visualization of both atrial cavities and the interatrial septum, the tip of the catheter including the optical fiber tip as well as the flow direction of contrast echoes during the laser firing. Blood clotting with thrombus formation was present following the cw mode of irradiation. The defects created in the interatrial septa of < or = 0.3 mm in diameter had irregular black borders and, histopathologically, were surrounded by a zone of coagulation necrosis of < or = 0.2 mm and vacuolization (vacuoles of < 0.1 mm in diameter). After 30 s of lasering a huge defect was conspicuous in the interatrial septum which extended up to the right and left atrial roof. The chopped mode of irradiation induced less blood clotting and narrow channels of < or = 0.08 mm through the interatrial septa with a small zone of coagulation necrosis of < or = 0.05 mm and without carbonization and vacuolization. This study demonstrates that laser atrial septostomy is technically feasible. However, prior to the extension of the method to humans, further investigation especially considering other laser power sources, possibly more suitable for this application such as Neodymium-YAG or Excimer lasers is warranted.