In vitro cytotoxicity of montelukast in HAPI and SH-SY5Y cells.

Montelukast is a cysteinyl leukotriene (CysLT) receptor antagonist with efficacy against a variety of diseases, including asthma and inflammation-related conditions. However, various neuropsychiatric events (NEs) suspected to be related to montelukast have been reported recently, with limited understanding on their association and underlying mechanisms. This study aimed to investigate whether montelukast can induce neuroinflammation and neurotoxicity in microglial HAPI cells and neural SH-SY5Y cells. The present study also compared the effects of montelukast with a 5-lipoxygenase inhibitor (zileuton) and a cyclooxygenase-2 inhibitor (celecoxib) to better understand modulation of related pathways. HAPI or SH-SY5Y cells were treated with the indicated drugs (3.125 µM-100 µM) for 24 h to investigate drug-induced neuroinflammation and neurotoxicity. Montelukast induced cytotoxicity in HAPI cells (50-100 µM), accompanied with caspase-3/7 activation, prostaglandin E2 (PGE2) release, and reactive oxygen species (ROS) production. Whilst both montelukast and zileuton down-regulated CysLT release in HAPI cells, zileuton did not significantly affect cell viability or inflammatory and oxidative factors. Celecoxib decreased HAPI cell viability (6.25-100 µM), accompanied with increasing caspase-3/7 activation and ROS production, but in contrast to montelukast increased CysLT release and decreased PGE2 production. Similar to observations in HAPI cells, both montelukast and celecoxib (50-100 µM) but not zileuton produced toxicity in SH-SY5Y neuroblastoma cells. Similarly, CM from HAPI cells treated with either montelukast or zileuton produced toxicity in SH-SY5Y cells. The results of the current study show the capability of montelukast to directly induce toxicity and inflammation in HAPI cells, possibly through the involvement of PGE2 and ROS, and toxicity in undifferentiated SH-SY5Y neuroblastoma cells. The current study highlights the importance of consideration between benefit and risk of montelukast usage and provides references for future investigation on decreasing montelukast-related NEs.

The intravenous adenosine test: a new test for the identification of bradycardia pacing indications? A pilot study in subjects with bradycardia pacing indications, vasovagal syncope and controls.

BACKGROUND: Intravenous adenosine has recently been used in the diagnosis of unexplained syncope, but there is no consensus as to the meaning of a 'positive' test. The objective is to determine the sensitivity and specificity of intravenous adenosine testing in the diagnosis of bradycardia-pacing indications [sinus node dysfunction(SND), atrio-ventricular block (AVB) and cardio-inhibitory carotid sinus syndrome (CSS)]. DESIGN: Pilot cohort study. METHODS: Patients-(i) Bradycardia-pacing group: Consecutive patients referred for pacing for SND, AVB and CSS; (ii) Consecutive head-up tilt (HUT)-positive VVS patients. Controls-(i) Simple controls (S-Con: normal examination/ECG) and (ii) Electrophysiology controls (EP-Con: consecutive subjects referred for accessory pathway ablation). Pacing referrals and EP-Con had electrophysiology studies to confirm referral diagnosis and exclude others. All subjects had bolus injection of 20 mg intravenous adenosine during continuous ECG and blood pressure monitoring (positive test: >or=6 s asystole, >or=10 s high-degree AVB post-injection). Sensitivity, specificity, safety and tolerability of the test were measured. RESULTS: Of 264 potential participants (4 SND, 8 AVB, 7 CSS, 10 VVS, 10 EP-Con and 11 S-Con) 50 were studied. All (100%) of the bradycardia-pacing group were adenosine test-positive, as were 6 (60%) VVS. None (0%) and 3 (27%) of the EP- and S-Con groups were positive. Adenosine testing was 100% sensitive and 86% specific for bradycardia-pacing indications, and 100% specific using the diagnostically 'clean' EP-Con results. There were no significant adverse or side effects. CONCLUSION: Adenosine testing reliably identified patients with definitive bradycardia-pacing indications in whom alternative diagnoses were excluded. Further work is needed to evaluate the role of this test in the diagnosis of unexplained syncope.

Pacing in elderly recurrent fallers with carotid sinus hypersensitivity: a randomised, double-blind, placebo controlled crossover trial.

OBJECTIVES: While carotid sinus syndrome (CSS) is traditionally defined by the association of carotid sinus hypersensitivity (CSH) with syncope, uncertainty remains over the role, if any, of complex pacing in patients with CSH and unexplained or recurrent falls. We sought to clarify the role of dual chamber pacing in this patient group in the first placebo-controlled study in CSH. DESIGN: Randomised, double-blind, crossover, placebo-controlled trial. SETTING: Specialist falls and syncope facility. PATIENTS: Consecutive subjects aged over 55 years with CSH as the sole attributable cause of three or more unexplained falls in the 6 months preceding enrolment. INTERVENTION: Dual-chamber permanent pacing with rate-drop response programming. The pacemaker was switched on (DDD/RDR) or off (ODO (placebo)) for 6 months, then crossed over to the alternate mode for a further 6 months, in randomised, double-blind fashion. MAIN OUTCOME MEASURE: The primary outcome measure was number of falls in paced and non-paced modes. RESULTS: Twenty-five of 34 subjects (mean 76.8 years (SD 9.0), 27 (79%) female) recruited completed the study. Pacing intervention had no effect on number of falls (4.04 (9.54) in DDD/RDR mode, 3.48 (7.22) in ODO; relative risk of falling in ODO mode 0.82, 95% CI 0.62 to 1.10). CONCLUSION: Permanent pacing intervention had no effect on fall rates in older patients with CSH. Further work is urgently needed to clarify the role, if any, of complex pacing in this patient group.

A randomized phase II trial comparing every 3-weeks carboplatin/paclitaxel with every 3-weeks carboplatin and weekly paclitaxel in advanced non-small cell lung cancer.

BACKGROUND: The optimal schedule of taxane administration has been an area of active interest in several recent clinical trials. METHODS: To address a pure schedule question, we randomized 161 patients with advanced stage IIIB or IV non-small-cell lung cancer (NSCLC) to either paclitaxel 225 mg/m2 every 3 weeks x 4 cycles or 75 mg/m2/week x 12 (cumulative dose on each arm = 900 mg/m2). Both arms received concurrent carboplatin AUC 6 every 3 weeks x 4 cycles. RESULTS: The two arms were well-balanced in terms of known prognostic factors. The overall response rate and survival outcomes were similar on the two arms. There was significantly more grade 3/4 thrombocytopenia and grade 2-4 anemia on the weekly arm but less severe myalgias/arthralgias and alopecia. No difference in the rates of peripheral neuropathy was observed; however, patients on the every 3 weeks arm reported significantly more taxane therapy-related side-effects on the functional assessment of cancer therapy taxane subscale. CONCLUSIONS: This randomized trial exploring schedule-related issues with carboplatin/paclitaxel confirms the versatility of this regimen.

Pacing to restore right ventricular contraction after surgical disconnection for arrhythmia control in right ventricular cardiomyopathy.

Ventricular tachycardia in ARVC (arrhythmogenic right ventricular cardiomyopathy) is typically managed by ICD implantation, with a limited role of catheter ablation. Surgical disconnection of the right ventricular (RV) has been used to control ventricular tachycardia (VT) in ARVC, but it often led to refractory RV failure due to loss of RV contraction after surgery. We report multisite pacing to recruit the disconnected RV to prevent ventricular failure.

Catheter interventions for congenital heart disease in third world countries.

The term "Third World" loosely encompasses a group of middle- and low-income countries. Considerable differences exist in health care delivery and health indices among these countries. The vast majority of children in the Third World do not have health insurance for congential heart disease (CHD). Catheter interventions for CHD are expensive because of installation costs of expensive biplane equipment, the requirement of dedicated personnel, and the need to stock a large inventory of expensive hardware. As a result, many catheter intervention procedures are beyond the reach of the average patient in the developing world. The following cost-effective strategies have evolved in selected institutions that have attempted to perform catheter interventions for CHD at an affordable cost: sharing of space, equipment, and support personnel with a busy adult cardiology program; use of single plane equipment; the development of sedation protocols to reduce the need for anesthesiologists; strategies to reduce procedure time; reuse of hardware through ethylene oxide sterilization; improvisations to use adult hardware items for CHD interventions; judicious case selection; and improvised alternatives to occlusive devices. These strategies may help reduce costs and allow a larger proportion of patients in developing countries with CHD to undergo interventions. However, the safety of these strategies and the cost savings need to be carefully evaluated prospectively.

Transcatheter coil occlusion of the arterial duct; results of the European Registry.

AIMS: To report on the data, collected by the Association for European Paediatric Cardiology (AEPC) Registry, on transcatheter coil occlusion of the arterial duct. METHODS AND RESULTS: A retrospective study was conducted of intention-to-treat data from 30 European and Middle Eastern tertiary referral centres which included an analysis of causes of suboptimal outcome. Since 1994, reports have been made on 1291 attempted coil occlusions of the arterial duct in 1258 patients. Median age at procedure was 4 years (range 0.1-52) and median weight was 29 kg (range 1.8-100). Following coil implantation, the immediate occlusion rate was 59%, which rose to 95% at 1 year. A suboptimal outcome occurred on 129 occasions (10% of procedures) and was defined as coil embolization, an abandoned procedure, persistent haemolysis, residual leak requiring a further procedure, flow impairment in adjacent structures and duct re-canalization. A number of clinical factors were chosen but only increasing duct size [odds ratio of 2.6:1 (CI 2-3.2)] and the presence of a tubular shaped duct [odds ratio 2.4:1 (CI 1.4-4)] were positively associated with an unfavourable outcome. CONCLUSION: The results of the European Registry support the view that transcatheter coil occlusion of the persistent arterial duct is a safe and effective procedure. Unfavourable outcomes are more likely when closing larger and/or tubular shaped ducts.

Stent implantation for superior vena cava occlusion after the Mustard operation.

A 25-year-old man who had undergone a Mustard repair for complete transposition of the great arteries 21 years previously developed complete occlusion of the superior vena cava and obstruction of the inferior vena cava. Transcatheter recanalization was performed using needle puncture of the superior obstruction followed by stent implantation into both systemic venous pathways with relief of obstructive symptoms.

Catheter closure of coronary artery fistulas.

Coronary artery fistulas are rare and vary widely in their morphological appearance and presentation. This paper presents experience of catheter closure of coronary artery fistulas in 40 patients. Catheter closure was performed with a variety of techniques, including detachable balloons, stainless steel coils, controlled-release coils, controlled-release patent ductus arteriosus (PDA) coils, and Amplatzer PDA plug. The vast majority of the fistulas were occluded with coils and in particular, controlled-release coils. Successful occlusion of the fistula was achieved in 39 (97%) of 40 patients. In one patient, the detachable balloon deflated prematurely and the patient underwent elective surgery. One 4-month-old infant died approximately 6 hours after the procedure. Immediate occlusion of the coronary artery fistula occurred in 33 (82%) of patients and late occlusion in 4 patients. Thus overall, total occlusion was achieved in 37 (97%) of 39 patients. The main complication was embolization of the occlusion device, which occurred in 6 (17%) of cases. In one of these cases, a detachable balloon deflated prematurely, and in five patients, coils embolized and were retrieved. In one of the patients, all six coils embolized 24 hours after the procedure but were retrieved, and further coils were implanted successfully. Controlled-release coils have made an important contribution to the technique of catheter closure of coronary artery fistulas. Catheter closure of these fistulas is an acceptable alternative to the standard surgical treatment.

The effects of ulnar axial malalignment on supination and pronation.

BACKGROUND: Forearm fractures are common injuries in both adults and children. Despite efforts to obtain anatomical alignment, axial rotational malunions occur, resulting in a decreased range of motion and a poor appearance. The objective of this study was to quantify loss of forearm rotation after simulation of ulnar malunions in supination and pronation. METHODS: Six fresh-frozen cadaveric upper extremities (mean age at the time of death, 79.4+/-2.8 years) were used to quantify loss of forearm rotation after simulation of axial rotational malunions of the ulna. First, maximum forearm rotation in supination and pronation was measured at torques of 6.8, 13.6, and 20.4 kilograms-centimeter applied with use of a custom jig. Following a midshaft ulnar osteotomy, a custom adjustable internal fixation plate was used to simulate axial rotational malunions of the ulna of 0, 15, 30, and 45 degrees in both directions. Measurements in supination and pronation were then repeated at the prespecified torques. Analysis of variance, with a p value of 0.05, was used for statistical analysis. RESULTS: In all instances, a decrease in forearm rotation after simulation of the ulnar rotational malunion was accompanied by an increase in rotation in the opposite direction. Supination and pronation were significantly influenced, whereas the total arc of rotation was not affected by ulnar rotational malunion. At a torque of 20.4 kilograms-centimeter, pronation malunions of 15, 30, and 45 degrees resulted in a mean loss of supination (and standard error of the mean) of 5+/-1, 11+/-1, and 20+/-1 degrees, respectively, and supination malunions of 15, 30, and 45 degrees resulted in a mean loss of pronation of 4+/-1, 10+/-2, and 18+/-4 degrees, respectively. The ratio of the simulated rotational malunion to the loss of motion was larger than one. CONCLUSIONS: Ulnar rotational malunions do not lead to a significant change in the total arc of forearm rotation. Instead, loss of motion in one direction is accompanied by increased motion in the opposite direction. Even with a 45-degree ulnar rotational malunion, forearm rotation decreases no more than 20 degrees.

A European multicentric experience using the CardioSEal and Starflex double umbrella devices to close interatrial communications holes within the oval fossa.

In this review, we describe the experience from 13 European centres using the CardioSEAL and Starflex double umbrella devices to close interatrial communications within the oval fossa (so-called 'secundum' defects). Between October 1996 and April 1999, the procedure was attempted in 334 patients with a mean age of 12 years and a mean weight of 44kg. The mean measured stretched diameter of the defect was 15 mm. In the overall group, the defect was solitary in 245 patients (73%), multiple in 21 (6%), associated with an aneurysm of the flap valve in 15 (5 %), was represented by patency of the oval foramen in 44 (13%), and was a fenestration in a Fontan repair in 9 (3%). In all patients, the devices were inserted under general anesthesia, using fluoroscopic and transesophageal echocardiographic control. Implantation was achieved in 325 (97,3%). The device embolized within either a few minutes or a few hours in 13 patients (4%). Of these, uncomplicated surgical repair was undertaken in 10, while the device was retrieved in 3 using catheters and a second device was successfully implanted. Residual shunting was detected immediately after the procedure in 41% of the patients, with the incidence decreasing to 31% at discharge, 24% at 1 month, 21% at 6 months, and 20.5% at one year. During the period of follow-up, elective surgical repair became necessary in two patients, due to malposition of the device in one, and late embolization in the other. Fractures of arms were seen in 6.1 %, most commonly with the largest devices. All those with fractured arms of the device were asymptomatic, and no clinical complications related to the fractures were observed. There were no arrhythmias, endocarditis, valvar distortion, thromboembolic events, or other complications. After one year of follow-up, clinical success, defined as complete closure of the defect or presence of only a trivial leak, had been obtained in 92.5% of the patients. We conclude, therefore, that these devices produce excellent results when used to close defects of small to moderate size. Results are less than optimal, or else complications ensure, when attempts are made to close very large defects.

Intracardiac pressures in the human fetus.

OBJECTIVE: To obtain normal values for intracardiac pressures in the human fetus. DESIGN: Intracardiac pressures were measured directly in the four chambers of the human fetal heart during clinically indicated invasive obstetric procedures. SETTING: Department of fetal medicine in a tertiary referral centre. PATIENTS: 39 fetuses between 16 and 29 weeks of gestation. RESULTS: The ventricular waveforms obtained were similar to those found in postnatal life. There was an increase in ventricular systolic and end diastolic pressures with advancing gestation. There was no difference between left and right ventricular pressures. Atrial pressures were equal and remained constant in the gestational age range studied. CONCLUSIONS: Fetal cardiovascular pressure measurements in the normal fetus assist in understanding the fetal circulation, and provide a basis for the assessment of cases of congenital heart disease that may be amenable to intrauterine treatment.

Evaluation of myocardial perfusion using positron emission tomography in infants following a neonatal arterial switch operation.

This study was performed to examine the use of positron emission tomography (PET) as a method of evaluating myocardial perfusion after the arterial switch operation for correction of transposition of the great arteries. Eleven asymptomatic patients (median age 2.3 years, range 1.3-4.3 years) post successful neonatal arterial switch repair for transposition underwent cardiac PET scanning using N(13) ammonia before and after dipyridamole infusion. Reconstructed data from static scans were analyzed for regional perfusion defects before and after pharmacological stress. Simultaneous assessment of coronary flow before and after stress was performed using a Patlak graphical analysis of data from dynamic scans. Results obtained from PET scanning were correlated with patterns of coronary artery anatomy, electrocardiogram (ECG) recordings, and echocardiographic evaluation. PET scanning demonstrated normal distribution of myocardial perfusion before and after stress in all but one patient, who was found to have a discrete inferior transmural perfusion defect. The defect was well correlated with perioperative ECG changes and a complicated postoperative course. Myocardial blood flow before dipyridamole (0.690 ml/min/g) was similar to reported adult rest values. There was a small but significant (p < 0.002) increase in myocardial blood flow after dipyridamole stress with a mean coronary flow reserve of 1.19 (+/-0.103). Echocardiographic evaluation failed to demonstrate significant wall motion abnormalities in any of the patients. Cardiac PET scanning is a reliable noninvasive method for evaluation of myocardial perfusion in small children. In this study, the incidence of myocardial perfusion defects after the arterial switch operation is lower than previously reported. The data obtained concerning coronary flow and coronary flow reserve after the arterial switch need to be interpreted with caution because normal data in children are not available.

Second-line gemcitabine in refractory stage IV non small-cell lung cancer: a phase II trial.

Two recent trials have suggested that docetaxel improves survival in the second-line treatment of non small-cell lung cancer (NSCLC) refractory to first-line platinum-based regimens. Given this, it is appropriate to continue to address the role of new agents in the second-line treatment of refractory NSCLC. Gemcitabine is a well-tolerated new agent that has been shown to have activity in NSCLC. Thirty-one previously treated patients with NSCLC were entered in this study. Eight patients had responsive disease (defined as response to first-line therapy lasting greater than or equal to 3 months) and 23 had refractory disease (defined as progressive disease on first-line therapy or progression less than 3 months from completing first-line therapy). Gemcitabine (1250 mg/m2) was infused over 30 minutes on days 1, 8, and 15 every 28 days. Quality of life (QOL) was assessed with each cycle using the Functional Assessment Cancer Therapy-Lung (FACT-L) questionnaire. Two patients (6.5%) had a partial response, and nine (29%) had disease stabilization. The most frequent grade 3/4 toxicity was myelosuppression, but this only occurred in 8% of doses delivered. Fifty-two percent of evaluable patients had stable or improved QOL over baseline, 10% had a decline in QOL, and the remainder completed only baseline questionnaires. Twenty-nine patients have died of progressive NSCLC; two patients remain alive. Overall, the 31 patients have a median survival of 5.1 months (95% confidence interval [CI]: 4.2-7.4 months) and 1-year survival rate of 16% (95% CI: 3%-29%). Gemcitabine was well tolerated in this patient population. An objective response rate of 6.5% was observed although a significant proportion of patients (29%) experienced stable disease, which may have impacted on their survival. QOL was improved or maintained in over half of the patients. Given these data, gemcitabine as a single agent is a therapeutic option for patients with refractory NSCLC.

Stent implantation for aortic coarctation and recoarctation.

OBJECTIVE: To determine the early results of balloon expandable stent implantation for aortic coarctation or recoarctation. DESIGN: Prospective observational study. SETTING: Two paediatric cardiology tertiary referral centres. PATIENTS: 17 patients, median age 17 years (range 4.4 to 45) and median weight 61 kg (17 to 92). Six had native aortic coarctation and 11 had aortic recoarctation; 14 had upper limb systolic hypertension. Of those with recoarctation, eight had had at least one previous balloon dilatation attempt and two of these patients also had further surgical interventions. INTERVENTION: Balloon expandable Palmaz iliac stent implantation. MAIN OUTCOME MEASURES: Systolic pressures gradients, minimum aortic diameter, upper limb blood pressures, and incidence of aneurysm formation. RESULTS: 18 stents were implanted during 18 procedures in the 17 patients. Mean peak systolic pressure gradient fell from 26 mm Hg (95% confidence interval (CI), 21 to 31 mm Hg) before to 5 mm Hg (2 to 8 mm Hg) after stent implantation (p < 0.001), and mean minimum aortic diameter increased from 7 mm (95% CI, 6 to 8 mm) before to 11.3 mm (10 to 12.6 mm) after implantation (p < 0.001). Complications occurred in five patients (bleeding in two, stent migration in two, and aneurysm formation in one). Two patients remained borderline hypertensive and eight were receiving antihypertensive treatment at most recent assessment. CONCLUSIONS: Stent implantation for aortic recoarctation and native coarctation gives good immediate results. Careful follow up is necessary to evaluate complications and the long term effect on blood pressure.

Middle aortic syndrome treated by stent implantation.

OBJECTIVES: To determine outcome of stent implantation in patients with middle aortic syndrome. DESIGN: Prospective study, case series. SETTING: A tertiary paediatric cardiology centre in a children's hospital. PATIENTS: Five patients, aged 4 to 17 years (mean 11.4 years), with upper limb hypertension due to middle aortic syndrome. INTERVENTION: Stents were implanted in the mid/lower thoracic/upper abdominal aorta. MAIN OUTCOME MEASURE: Satisfactory deployment of stents and blood pressure control. RESULTS: In all patients, angiocardiography showed long segment stenosis in the mid or lower thoracic/upper abdominal aorta. The pressure gradient was between 40 and 90 mm Hg (mean 63.2 mm Hg). Seven Palmaz stents were implanted. Immediately after implantation, the gradient decreased to between 0 and 35 mm Hg (mean 13.6 mm Hg). Angiography showed a satisfactory result with widely patent stents in all. In one patient, thrombosis of the stent occurred six days after implantation. This was successfully treated with infusion of alteplase, further balloon dilatation, and implantation of a second stent overlapping the first, both dilated to 10 mm diameter. One patient had elective redilatation of the stent six months after implantation, with further reduction of the gradient from 35 mm Hg to 10 mm Hg. At the latest follow up between three and 20 months (mean 12.2 months) after stent implantation, in four patients blood pressure was better controlled with antihypertensive drugs. One patient was normotensive without drugs. Computed tomography showed no aneurysm formation in the region of the stents. CONCLUSIONS: Stent implantation is a preferable alternative to surgery in the treatment of patients with middle aortic syndrome and merits further evaluation.

Transcatheter closure of atrial septal defects within the oval fossa: medium-term results in children using the 'ASDOS'-technique.

OBJECTIVES: The purpose of this study was to evaluate the safety and efficacy of the ASDOS-technique (Sulzer-Osypka GmbH, Germany) for transcatheter closure of atrial septal defects within the oval fossa. BACKGROUND: Although several attempts have been made to occlude defects within the oval fossa by transcatheter techniques, none of these has gained general acceptance. METHODS: Patients with a defect in the oval fossa measuring equal to or less than 20 mm diameter, with a residual septal rim of 5 mm or greater, body weight greater than 10 kg, with clinical indications for surgical closure were considered for transcatheter closure. Follow-up investigations were performed at discharge, after 1, 3, 6 and 9 months, as well as after 1 and 2 years. RESULTS: Of 78 patients considered for closure, a device was inserted in 41 patients (53%), with success being achieved in 40 patients (98%). The ages ranged from 1.1 to 15 years (7.8 +/- 1.92 years), the 'stretched' diameter of the defect from 10 to 20 mm (14.7 +/- 2.60 mm), and the diameters of the inserted devices from 25 to 45 mm (33.2 +/- 5.43 mm). Transient impairment of atrioventricular conduction occured in 4 patients. During the follow-up of 23.0 +/- 5.6 months elective surgical closure of a residual shunt was performed 26 months after insertion of the device in one patient. None of the other patients required surgery, hospitalisation or medical treatment, and none is requiring further treatment of the defect within the oval fossa. Fracture of one arm of the device occurred in 4 patients, but the fractured arms are in an unchanged and stable position after a period of at least 19 months. CONCLUSIONS: Our medium-term data show that transcatheter closure in children of defects within the oval fossa can be performed with a high efficacy and safety using the ASDOS-device.

Effects of modified and classic Blalock-Taussig shunts on the pulmonary arterial tree.

BACKGROUND: The aim of this study was to assess by angiography the late effects of both classic and modified Blalock-Taussig shunts in terms of growth and development of stenosis and distortion. METHODS: At a mean of 51 months postoperatively, we retrospectively reviewed the results in 78 patients who underwent creation of Blalock-Taussig shunts (25 classic and 71 modified). RESULTS: At the level of the anastomosis, the shunt caused a reduction in diameter of the pulmonary artery in 49% of all shunts, major stenosis (>50% narrowing of the lumen) in 14%, and distortion of the pulmonary artery in 19%, findings that did not correlate with the type of shunt. Distortion did correlate with younger age at the time of shunt operation (p=0.01). CONCLUSIONS: After a Blalock-Taussig shunt, growth of the pulmonary arteries occurred but did not exceed the normal growth of the pulmonary arterial tree. Moreover, a shunt procedure can cause distortion and stenosis of the pulmonary artery, which may have important implications for future corrective surgical intervention. All these findings support earlier complete surgical repair of correctable congenital cardiac defects.

Growth of the right ventricle after successful transcatheter pulmonary valvotomy in neonates and infants with pulmonary atresia and intact ventricular septum.

OBJECTIVES: Since 1990, transcatheter pulmonary valvotomy has become an alternative to surgical valvotomy in the management of neonates and infants with pulmonary atresia and intact ventricular septum. We sought to determine whether right ventricular growth after transcatheter pulmonary valvotomy is commensurate with body growth. METHODS: Laser or radiofrequency-assisted balloon valvotomy was attempted in 12 neonates and infants with pulmonary atresia and intact ventricular septum. Tricuspid and mitral valve dimensions were measured retrospectively on the cross-sectional echocardiograms performed before the procedure and during follow-up. Z-values were used to standardize tricuspid valve dimensions with body size. RESULTS: The atretic pulmonary valve was successfully perforated and dilated in nine of 12 patients. Five of these nine patients required additional transcatheter or surgical procedures to augment the pulmonary blood flow. Of six survivors, five are regularly followed up with a median follow-up of 60 months (range 37 to 68 months). All five have two-ventricle circulation, two of the five patients requiring surgical enlargement of the right ventricular outflow tract with or without closure of the atrial septal defect. Echocardiographic tricuspid valve dimensions and Z-values before transcatheter valvotomy tended to be smaller in the patients who died than in the survivors. In the survivors, the absolute tricuspid valve dimensions increased after valvotomy but the Z-values tended to decrease or stayed constant. CONCLUSIONS: Transcatheter valvotomy is a good alternative to surgical valvotomy in patients with pulmonary atresia and intact ventricular septum. Two-ventricle circulation can be achieved despite subnormal right ventricular growth.