Evaluation of the diagnostic work-up in children with myocarditis and idiopathic dilated cardiomyopathy.

The underlying etiology of dilated cardiomyopathy (DCM) in children varies, 14-22% is secondary to myocarditis, and the majority remains idiopathic. Etiology has prognostic value; however, 'a clinical diagnosis of myocarditis' has been frequently used because the gold standard [endomyocardial biopsy (EMB)] is often not performed. Therefore, a consistent diagnostic approach and interpretation is needed. In this multicenter study, we evaluated the diagnostic approach and interpretation of the viral results in children with myocarditis and idiopathic DCM. We included 150 children with DCM, of whom 103 were assigned the diagnosis myocarditis (n = 21) or idiopathic DCM (n = 82) by the attending physician. Viral tests were performed in 97/103 patients, in only 34% (n = 35) some of the tests were positive. Of those patients, we evaluated the probability of the assigned diagnosis using the viral test results. We classified viral test results as reflecting definite or probable myocarditis in 14 children and possible or unlikely myocarditis in 21 children. Based on this classification, 23% of patients were misclassified. We found that in children with DCM, the diagnostic approach varied and the interpretation was mainly based on viral results. Since a 'clinical diagnosis of myocarditis' has been frequently used in daily practice because of the lack of EMB results, a uniform protocol is needed. We propose to use viral test results in several steps (blood PCR, serology, PCR and/or cultures of the gastro-intestinal and respiratory tract, and EMB results) to estimate the probability of myocarditis.

The use of transesophageal echocardiography monitoring of transcatheter closure of a persistent ductus arteriosus.

We performed transesophageal echocardiography (TEE) with pediatric biplane probes throughout the procedure of transcatheter closure of the ductus arteriosus in 42 out of 46 patients who were scheduled for this intervention. Patient ages ranged from 15 months to 14 years and body weight from 9-53 kg. Both Rashkind double umbrella devices and coils were used. The described approach resulted in fewer contrast injections and was helpful in monitoring the procedure and in deciding when to release the device. To the best of our knowledge this is the first report describing a large series where continuous monitoring of transcatheter ductus closure was combined with x-ray fluoroscopy and TEE.

Neonatal pulmonary hypertension during extracorporeal membrane oxygenation.

OBJECTIVES: This prospective study was designed to monitor severe pulmonary hypertension during extra corporeal membrane oxygenation using echo Doppler variables. BACKGROUND: All neonates treated with extracorporeal membrane oxygenation also have severe pulmonary hypertension. A study which monitors the reaction of the pre-existing pulmonary hypertension during extracorporeal oxygenation by frequent sampling of those variables related to pulmonary pressure is still lacking. Such a study is necessary to analyze the complex haemodynamic changes in patients undergoing extracorporeal membrane oxygenation. METHOD: In 29 neonates, we estimated pulmonary arterial pressure using peakflow velocity of regurgitation across the tricuspid- and pulmonary valve, peakflow velocity of shunting across persistent arterial ductus, and systolic time intervals of the right ventricle. Correlation between the several estimations of pulmonary arterial pressure were analysed with the Spearman correlation coefficient. RESULTS: Systolic pulmonary arterial pressure measured by the velocity of tricuspid regurgitation illustrated severe pulmonary hypertension prior to extra corporeal membrane oxygenation (mean 63 mmHg, sd 20). Similar levels for the systolic pulmonary arterial pressure could be derived (mean 73 mmHg, sd 17) from ductal shunting. A fair correlation of 0.76 (p< 0.002) could be demonstrated. Pulmonary hypertension responded well and quickly to treatment by extra corporeal membrane oxygenation, with reductions within 24 hours to mean systolic levels of 35 mmHg, sd 23. This very early reaction has not previously been demonstrated and could be of importance in defining parameters for weaning from cardiopulmonary bypass. Diastolic pulmonary arterial pressure was investigated because of its relation to vascular resistance. It proved more difficult to measure because of the low incidence of pulmonary regurgitation. Derived diastolic pressures did not show any good correlations. CONCLUSION: Pulmonary hypertension is well documented prior to extra corporeal membrane oxygenation and response very quickly to the institution of treatment. Ultra sound techniques are indicated at the bedside, and prove useful in monitoring pulmonary blood pressure during the procedure.

Pulmonary perfusion after endovascular stenting of pulmonary artery stenosis.

UNLABELLED: Pulmonary artery stenosis is a well-known condition after surgical correction of tetralogy of Fallot. Endovascular stenting of the stenosis is a new technique for correction without surgical intervention. Objective evaluation of the procedure, however, is often hampered by moderate or severe pulmonary valve insufficiency. This disadvantage does not apply to 99mTc-macroaggregates of albumin (MAA) scintigraphy of the lungs. Moreover, quantification can be performed relatively easy. METHODS: Seven patients with surgically corrected tetralogy of Fallot (4 men, 3 women, mean age 15.7 yr, range 5-24 yr) were studied. The mean diameter decrement of a pulmonary artery was 69% +/- 8.7%. Before and after stenting, relative uptake in the left and right lung was assessed after injection of 37-55 MBq 99mTc-MAA. Three patients were studied twice after stenting. RESULTS: In all patients, perfusion of the affected lung increased significantly: before 22.7% +/- 10.8%, after 38.6% +/- 12.3% (p < 0.0001). All patients claimed clinical improvement of their condition after stenting. The perfusion gain did not correlate with the prestenting diameter decrement or with the pressure gradient over the stenosis. Lung uptake in the patients studied twice after stenting was similar between the initial and poststenting study (< or = 2% difference). CONCLUSION: Quantitative 99mTc-MAA lung imaging is a noninvasive technique without patient discomfort that objectively measures the effect of stenting pulmonary artery stenosis. The final outcome of stenting with regard to increment of pulmonary blood flow is not predicted by the severity of the stenosis or the pressure gradient over the stenosis.

[Endovascular stent in the treatment of residual pulmonary stenosis in patients operated on for congenital heart defects; initial results]. / Endovasculaire stent ter behandeling van resterende pulmonalistakstenose bij patiënten geopereerd wegens aangeboren hartafwijking; eerste ervaringen.

OBJECTIVE: Evaluation of the preliminary results of stent implantation as a new technique of intervention cardiology to treat (residual) stenosis of pulmonary arteries in congenital heart disease. DESIGN: Descriptive. SETTING: Children's Heart Centre, University Hospital Nijmegen, the Netherlands. METHODS: Data about physical condition, heart catheterization/angiography and lung perfusion scan were collected. Special attention was paid to the lung perfusion scan as a potential parameter of evaluation. RESULTS: The physical condition was not a useful parameter to judge the result of the pulmonary intravascular stenting, due to a simultaneously present important pulmonary valve insufficiency in most cases. Angiography showed a good result immediately after the procedure in all cases, except in one with kinking of the stent. The increase of lung perfusion could be confirmed by lung scintigraphy in most cases. The relative perfusion of the affected lung increased from 22.7% (SD: 10.8) to 38.6% (12.3) (p < or = 0.001). CONCLUSION: Percutaneous implantation of endovascular stents in pulmonary artery branch stenosis is a welcome alternative to (reconstructive) cardiac surgery. Objective quantification of this stenting by lung perfusion scintigraphy, a technique without patient discomfort, is possible.

Urokinase therapy in neonates with catheter related central venous thrombosis.

The results of fibrinolytic therapy with urokinase were evaluated in 26 neonates with catheter related central venous thrombosis. Complete thrombolysis could be achieved in 13 patients (50%), partial thrombolysis in 3 patients (12%). No effect was seen in 10 patients (38%). Therapy success was influenced by age, size and location of the thrombus. Coincidence of infection occurred in 16 patients (62%). Mild hemorrhagic complications were seen in 2 patients (8%), no other significant side effects were observed. Nine patients with residual thrombosis were treated with oral anticoagulants following urokinase resulting in resolution of the thrombus in 6 patients within 3 months (67%). The incidence of asymptomatic recurrent thrombosis was high (28%). Urokinase might be an effective and safe treatment for central venous thrombosis in neonates. Prophylactic antibiotic therapy during the infusion of urokinase and long-term treatment with oral anticoagulants after thrombosis are advisable. Early detection of thrombosis might enhance the success rate of fibrinolytic therapy. Therefore, we strongly recommend routine echocardiographic screening of central venous catheters.

Thrombus detection on central venous catheters in the neonatal intensive care unit.

Between September, 1989, and September, 1992, 193 infants were investigated prospectively for development of central-venous-catheter-induced thrombosis. In 25 infants intracardiac or central-venous-catheter-induced thrombosis was demonstrated (13%). A slightly higher incidence of thrombosis was found in infants with umbilical catheters in comparison with infants with subclavian catheters, although no significant difference was demonstrated. The results make clear that central venous catheters in neonatal intensive care have considerable risk in developing central venous or intracardiac thrombosis, and echocardiography is an excellent technique for diagnosing these thromboses.

[Purulent pericarditis in children. A continuously life-threatening disease]. / Purulente pericarditis bij kinderen. Een nog altijd levensbedreigend ziektebeeld.

Acute purulent pericarditis in children is usually fatal, if not recognized and adequately treated. The history of three children with acute purulent pericarditis is presented. In every septic child who presents with signs of right heart decompensation, acute purulent pericarditis should be seriously considered. Echocardiography is essential for the diagnosis. If possible, diagnostic pericardiocenthesis should be performed. Experience of the last years suggests that excellent results can be obtained when adequate surgical drainage and antibiotic therapy are combined.