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Biomedical subjects

M Witsenburg

Publications and source records attributed to M Witsenburg.

At least 37 records · Page 2Linked to original sources
PubMed1999

Vascular rings: a rare cause of common respiratory symptoms.

Upper airway symptoms or dysphagia may be caused by vascular anomalies, forming a ring around the trachea, oesophagus or both. To analyse the clinical presentation, use of various diagnostic techniques, treatment and follow-up we carried out a retrospective study of 38 children who had been diagnosed with a vascular ring between 1981 and 1996. We found 74% of the vascular rings to be symptomatic, with inspiratory stridor and wheezing as the main complaints. The delay between the onset of symptoms and diagnosis of a vascular ring in patients without associated anomalies ranged from 1 to 84 mo. Associated anomalies were found in 53% of cases and 80% of these anomalies consisted of associated cardiovascular malformations. Oesophagography proved to be a valuable diagnostic technique when a vascular ring was suspected. Echocardiography appeared to be of little value for the diagnosis of a vascular ring, but was essential to exclude associated cardiovascular malformations. Although angiography has always been considered to be the gold standard in the determination of the exact anatomy of vascular rings, increasing evidence is available that CT scan or MRI may replace this role. Mortality was related to co-existent tracheal deformities in 5/6 cases. Of the remaining, preoperatively symptomatic patients, relief of symptoms was achieved immediately after surgery in 43% and within 4 y after surgery in 57%. Prolonged and recurrent respiratory complaints or dysphagia in infancy or childhood should alert the paediatrician to the possibility of a vascular ring.

Aorta, Thoracic↗
PubMed1997

Clinical outcome and left ventricular function after pulmonary autograft implantation in children.

BACKGROUND: Aortic root replacement with a pulmonary autograft is an alternative treatment for children with aortic valve or root disease, or both. METHODS: Twenty-six patients (18 boys and 8 girls) with a mean age of 10.9 years (range, 0.3 to 16.9 years) underwent this procedures in a 7-year period. The mean follow-up period was 3.2 years (range, 0.2 to 7.5 years). RESULTS: During follow-up 3 patients died and one autograft was replaced with a mechanical valve. The actuarial survival and actuarial event-free survival rates were 87% and 79%, respectively, at both 5 and 7 years. None of the surviving patients had complaints, and all have done well and are living normal lives. Electrocardiographic signs of myocardial ischemia and left ventricular hypertrophy were not present. Echocardiography showed autograft valve regurgitation to be absent or trivial (n = 17) or mild (n = 5). Stenosis was not present. Increasing autograft annulus diameters were noted during follow-up, but this was not related to the severity of autograft regurgitation. Left ventricular dimensions and function were within normal limits later than 1 year after the operation. Only 2 patients had a moderate pulmonary stenosis without right ventricular hypertrophy. CONCLUSIONS: The surgical results, clinical outcome, valve function, and left ventricular function in our patients have been good. This procedure is recommended as a method of aortic valve replacement in children.

Actuarial Analysis↗
PubMed1995

The efficacy of flecainide versus digoxin in the management of fetal supraventricular tachycardia.

Fetal supraventricular tachycardia (SVT) can be successfully treated transplacentally, but in cases where fetal hydrops develops there is considerable morbidity and mortality. The present study was carried out to establish whether the introduction of flecainide altered obstetric management and fetal outcome. A retrospective analysis took place of 51 singleton pregnancies which were referred to the division of prenatal diagnosis because of fetal tachycardia between 1982 and 1993. SVT was documented in 50 out of 51 fetuses, one of which displayed a combination of extensive rhabdomyomas and severe hydrops and died shortly after referral. In the other fetus ventricular tachycardia was diagnosed. Of the remaining 49 fetuses, 14 did not receive any prenatal treatment, but nine needed postnatal treatment. Transplacental treatment of SVT took place in 35 fetuses, of which 22 presented without hydrops and 13 with hydrops. These subsets differed significantly with respect to restoration of normal sinus rhythm (73% vs. 30%; p < 0.001) and mortality (0% vs. 46%; p < 0.001). Digoxin was effective in restoring sinus rhythm in 55 per cent of the non-hydropic fetuses but in only eight per cent of the hydropic fetuses. Flecainide was effective in restoring sinus rhythm in all non-hydropic fetuses where digoxin treatment failed, and in 43 per cent of hydropic fetuses. Administration of flecainide resulted in a significantly reduced mortality (p < 0.001) compared with digoxin treatment. No adverse effects were seen. Postnatal anti-arrhythmic treatment was necessary in 23 infants. Treatment could be withdrawn within one year in all cases but one.

Anti-Arrhythmia Agents↗
PubMed1995

Arterial switch for pulmonary venous obstruction complicating Mustard procedure.

Two patients underwent an arterial switch procedure for the relief of severe pulmonary venous obstruction complicating a Mustard procedure. Without preparatory pulmonary banding, both patients had adequate left ventricular function due to secondary pulmonary hypertension. At 8 and 4 years after the procedure, both patients are in New York Heart Association functional class I, with echocardiographic evidence of good left and right ventricular function.

Heart Septal Defects, Atrial↗
PubMed1995

Aortic root replacement with a pulmonary autograft.

A series of 42 consecutive patients with exclusively aortic root replacement using the pulmonary autograft is presented. The mean age at operation was 19.3 years (range 0.3-41.4). Two patients died in hospital (4.8%; 70% CL: 0.0-8.2). This mortality was not related to the autograft procedure. The mean follow-up time was 30 months (range 3-70; SD: 20). Late mortality consisted of two patients; in one of these severe autograft failure occurred due to chronic juvenile rheumatoid arthritis. The estimated survival rate at 4 years was 88.8% (70% CL: 83.3-94.5). Morbidity involved three patients. One had a total heart block after operation, requiring pacemaker implantation and two patients were reoperated: one for severe autograft failure due to recurrent acute rheumatic fever and the other for severe stenosis at the distal anastomosis of the pulmonary allograft. Thromboembolic complications and endocarditis were not registered. Reoperations for technical or degenerative reasons were not necessary. The estimated event-free survival rate at 4 years was 78.7% (70% CL: 71.0-86.4). Serial echocardiography (n = 28) showed a significant increase of the autograft annulus diameter of 2.9 mm (SD: 2.7). Thirty-five of the 37 patients with an autograft in situ were in NYHA class I, and 2 in class II. At last follow-up precordial color Doppler echocardiography showed moderate aortic regurgitation in one patient and no, trivial or mild aortic regurgitation in 36 patients. Stenosis of the autograft was not observed. These medium-term results are promising with respect to mortality, morbidity and functional results.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Acute effects of balloon valvuloplasty and pacing on left ventricular performance in children with moderate pulmonary valve stenosis, analysed by systolic and diastolic pressure-volume relationships.

Right ventricular overload of volume and/or pressure type may affect left ventricular systolic and diastolic function. This has been shown in animal studies and has been suggested in non-invasive studies in man. Altered geometry of the left ventricle, myocardial hypertrophy and changes in contractile state may be responsible for the change in function. Balloon valvuloplasty is an effective treatment for isolated valvular pulmonary stenosis in children, and results in an immediate decrease of right ventricular systolic pressure. Whether this results in immediate changes in left ventricular performance is unknown. Eight children (age 5.2 to 13.9 years) with moderate pulmonary valve stenosis underwent pulmonary balloon valvuloplasty under general anaesthesia. Left ventricular function measurements before and after valvuloplasty were performed using a combined micromanometer-conductance catheter to obtain end-systolic (ESPVR) and end-diastolic (EDPVR) pressure-volume relationships employing inferior vena cava occlusion both at normal and pacing-induced increased heart rates. Pulmonary valvuloplasty resulted in a decrease in peak systolic right ventricular pressure from 62.8 +/- 13.5 to 34.4 +/- 7.3 mmHg (P < 0.001), without significant changes in left ventricular systolic and end-diastolic pressure, or in cardiac index. The ESPVR was fitted to a linear function to obtain the slope (Ees) and the volume intercept at 75 mmHg (V75). The EDPVR was fitted to an exponential function. At baseline, Ees was 1.68 +/- 0.99 mmHg.ml-1 and V75 was 33.6 +/- 21.8 ml. Neither valvuloplasty nor pacing, which increased mean heart rate from 81 to 112 beats.min-1 (P < 0.001), resulted in significant changes of the parameters Ees or V75.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Catheterization↗
PubMed1994

Anatomy of the proximal coronary arteries as a risk factor in primary repair of common arterial trunk.

The objective of this study was to investigate whether the proximal coronary arterial anatomy is a risk factor in surgical treatment of common arterial trunk, with special focus on the value of preoperative angiocardiography. A retrospective analysis was performed of all 22 patients who underwent primary surgical repair of the common arterial trunk, with a mean follow-up of 5.1 years. In 18 patients preoperative angiocardiography was performed. Anatomical features (angiocardiographical, surgical as well as post-mortem) of the proximal coronary arteries were investigated. With standard biplane angiocardiography single and dual coronary arterial systems could adequately be distinguished. However, the position of the coronary orifices in relation to the sinus of Valsalva could not adequately be identified. Three patients had coronary abnormalities without surgical consequences. In 2 cases the surgical approach had to be modified due to the coronary anatomy. Early mortality was 23% (5/22) and was correlated with worse functional class (p < 0.05) and earlier date of operation (p < 0.05). Late mortality was 5% (1/22). Five patients were reoperated, without mortality. Fourteen surviving patients are in functional class I, and 2 in class II. A further improvement of the surgical therapy of common arterial trunk might be provided by adequate appreciation of the proximal coronary arterial anatomy at surgery.

Abnormalities, Multiple↗
PubMed1994

Aortic root replacement with pulmonary autograft in children.

Between September 1988 and February 1993, 14 patients whose ages ranged from 3 months to 16 years (mean 11.1 +/- 4.3 years) underwent replacement of the aortic root with the autologous pulmonary root for aortic valve disease. The follow-up was 4 years (cumulative total of 25.2 patient-years). There was no early mortality. Late mortality (one patient) was 7.1% (95% confidence limits 0% to 21%). This patient had juvenile rheumatoid arthritis and died of consequent congestive heart failure with autograft failure 6 months after operation. Event-free survival after 4 years was 78.6% (95% confidence limits 50% to 95%). One patient was reoperated on because of autograft failure caused by a relapse of rheumatic fever. One patient operated on for critical neonatal aortic stenosis has subnormal exercise tolerance because of restrictive cardiomyopathy and pulmonary homograft regurgitation. The other 12 patients were in New York Heart Association functional class I at the end of follow-up. There was no prevalence of bacterial endocarditis. There were no signs of primary structural degeneration of the pulmonary autograft. During follow-up, in eight patients, increased anulus diameter of the pulmonary autograft could be demonstrated by precordial two-dimensional echocardiography, suggesting growth of the autograft. Our experience shows that aortic root replacement with the pulmonary autograft can be done with low mortality and morbidity in children with aortic valve disease. The operation seems to be contraindicated in children with juvenile rheumatoid arthritis because of the risk of recurrence of rheumatic disease in the autograft. The pulmonary autograft has also been shown to be susceptible to recurrence of rheumatic inflammation in children with a history of acute rheumatic fever. Despite pulmonary autograft replacement of the aortic valve in infants with critical valvular aortic stenosis and endocardial fibroelastosis, clinical results may be poor. Growth of the autograft is suggested by echocardiographic follow-up. We consider aortic root replacement with the pulmonary autograft the procedure of choice in children who require aortic valve replacement.

Adolescent↗
PubMed1993

Balloon valvuloplasty for valvular pulmonary stenosis in children over 6 months of age: initial results and long-term follow-up.

Between 1984 and December 1990 balloon valvuloplasty for valvular pulmonary stenosis was planned and performed in 92 children over 6 months of age (range 0.8-17.9 years). Valvuloplasty decreased the invasively determined peak systolic gradient from 61 +/- 34 (mean +/- SD) to 27 +/- 20 mmHg (P < 0.0001). At follow-up cardiac catheterization, performed in 22 patients after 13 +/- 5 months, the gradient was 22 +/- 23 mmHg (ns). Initially the continuous wave Doppler gradient decreased from 61 +/- 23 to 26 +/- 12 mmHg (P < 0.0001). It then remained unchanged both at early follow-up after 0.6 +/- 0.3 years, being 23 +/- 12 mmHg, and at long-term follow-up after 3 +/- 1.7 years (21 +/- 10 mmHg, ns). In the 41 patients treated before the end of 1986 the residual continuous wave Doppler gradient at long-term follow-up after 5.1 +/- 0.8 years was 21 +/- 10 mmHg. Mild pulmonary regurgitation was present in 77% of the patients at early follow-up and in 83% at the last follow-up. Right ventricular hypertrophy on the electrocardiogram was present in 83% of the children before valvuloplasty. At early follow-up it had decreased to 44% with a further decrease to 24% at the last follow-up. Comparison of patients with initial invasive systolic gradients greater and smaller than 50 mmHg revealed no differences between either group with regard to the continuous wave Doppler gradient at last follow-up, the incidence of pulmonary regurgitation and the occurrence of significant complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Balloon angioplasty for aortic recoarctation in children: initial and follow up results and midterm effect on blood pressure.

OBJECTIVE: To assess the direct and follow up results of balloon angioplasty for aortic recoarctation with respect to the type of initial operation and to determine the midterm effect on systolic blood pressure. DESIGN: Prospective study of invasive haemodynamic and angiographic data and non-invasive data on upper body blood pressure. SETTING: Tertiary referral centre for paediatric cardiology. SUBJECTS: 24 infants and children (age 0.3-16.2 years, mean 5.9 years) who had had surgical correction for coarctation (end to end anastomosis (14 patients) subclavian flap angioplasty (nine), patch angioplasty (one)). MAIN OUTCOME MEASURES: Peak systolic gradient over the recoarctation and aortic diameters before and directly after angioplasty and at follow up. Upper body blood pressure before and after angioplasty and at latest follow up. RESULTS: Mean peak systolic gradient initially decreased from 35 (15) to 12 (9) mm Hg (p < 0.001) and was 9 (10) mm Hg at follow up after 1.4 (0.5) years. Patients with a subclavian flap repair showed a slight further decrease in the residual gradient at follow up (p < 0.05). The coarctation diameter increased from 5.3 (2.6) to 7.7 (2.5) mm (p < 0.001), and a further increase to 9.3 (2.9) mm (p < 0.01) was present at follow up after 1.4 (0.5) years without significant changes in other aortic diameters. Upper body systolic blood pressure decreased from 138 (24) to 115 (17) mm Hg after balloon angioplasty, and the effect on blood pressure persisted at a mean follow up of 3.7 years. One patient died of ventricular failure. Femoral artery thrombosis occurred in three patients. In one patient a small aneurysm occurred that had not increased at follow up. In one patient restenosis after angioplasty was redilated successfully. In one patient dilatation of a residual stenosis after angioplasty failed. CONCLUSION: Balloon angioplasty for recoarctation is effective and is associated with accelerated growth of the dilated segment at follow up in many patients. The complication rate is acceptable. Midterm follow up shows persistent relief of upper body hypertension in most patients.

Adolescent↗
PubMed1992

Short- and midterm results of balloon valvuloplasty for valvular aortic stenosis in children.

During a 27-month period, 21 consecutive children (aged 0.1 to 15.7 years) with isolated valvular aortic stenosis underwent percutaneous transfemoral balloon valvuloplasty. Ten children had undergone earlier surgical valvulotomy. The indication for treatment was ST-T-segment changes at rest or during bicycle-ergometry, a continuous-wave Doppler-derived transvalvular gradient greater than 60 mm Hg or syncope, or a combination. Mean peak systolic left ventricular pressure decreased from 165 +/- 19 to 131 +/- 19 mm Hg (p less than 0.001). Mean end-diastolic left ventricular pressure did not change significantly (12 +/- 3 vs 11 +/- 5 mm Hg). Mean peak systolic valve gradient decreased from 71 +/- 23 to 22 +/- 11 mm Hg (p less than 0.001). Mean cardiac index remained unchanged (2.9 +/- 0.8 vs. 3.0 +/- 0.7 liters.min-1.m-2). Aortic valve regurgitation on angiography appeared or increased in 9 patients (up to grade 3 in 3 children). Noninvasive follow-up studies were performed for 2 to 4.2 years (mean 2.8). ST-T changes on the electrocardiogram at rest or during exercise were present in 6 patients before balloon valvuloplasty and had disappeared in all at 6-month follow-up. Reoccurrence of ST-T changes after a longer follow-up was associated with severe valve regurgitation. Syncope was not observed after balloon valvuloplasty. The continuous-wave Doppler gradient decreased from 94 +/- 36 to 49 +/- 15 mm Hg (p less than 0.001). After a follow-up of 2 to 4.2 years (mean 2.8) it remained unchanged (43 +/- 13 mm Hg; p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Management of fixed subaortic stenosis: a retrospective study of 57 cases.

Although recommended by several investigators, the benefit of early surgery in patients with fixed subaortic stenosis has not been proved. Findings were reviewed of 57 patients with isolated fixed subaortic stenosis, including 27 surgically treated patients, with special emphasis on the occurrence of aortic regurgitation during a mean follow-up period of 6.7 years. The number of patients with aortic regurgitation increased preoperatively in the total group (23% at diagnosis to 54% after 3.7 years of follow-up). The prevalence of aortic regurgitation in the 27 surgically treated patients was higher (81%) than that in the nonsurgically treated group but remained unchanged after a mean postoperative period of 4.7 years. In all patients but one, aortic regurgitation remained of minor hemodynamic significance. One patient died during follow-up. After surgery, 15 patients (55%) showed a relapse; 11 redeveloped a subvalvular pressure gradient greater than 30 mm Hg and discrete subvalvular ridges (range 6 months to 24 years after surgery, mean 7 years). In those patients with fixed subaortic stenosis, follow-up did not reveal any benefit from early surgery. The unpredictable course and sometimes very severe progression of this disease make frequent and careful follow-up necessary.

Adolescent↗
PubMed1991

Transesophageal echocardiographic monitoring of interventional cardiac catheterization in children.

Transesophageal echocardiography was used prospectively in 22 children scheduled for interventional cardiac catheterization (9 with pulmonary valvuloplasty, 5 with aortic valvuloplasty, 1 with pulmonary angioplasty, 2 with aortic angioplasty, 2 with patent ductus arteriosus occlusion and 3 with Mustard baffle dilation) to determine its potential value as a monitoring technique. The patients ranged in age from 0.9 to 14.6 years (mean 5.4) and in weight from 9.5 to 49.2 kg (mean 21.1). Studies were completed in all patients without complications. Preintervention studies provided important new information in two patients, leading to cancellation of the planned procedure. Major contributions of transesophageal monitoring included 1) a real time assessment of catheter placement across either atrioventricular valve and the aortic valve during balloon valvuloplasty; 2) immediate assessment of aortic valve and aortic wall morphology during balloon dilation; and 3) detailed morphologic and hemodynamic information together with enhanced catheter guidance during Mustard baffle dilation. After pulmonary valvuloplasty, partial chordal rupture of the tricuspid valve was documented in one patient. In two patients, balloon catheter position was modified according to the transesophageal findings. The assessment of changes in pulmonary valve morphology and transcatheter occlusion of a patent ductus arteriosus was not enhanced by single-plane transesophageal monitoring. Pulsed wave Doppler studies contributed additional information in the assessment of immediate hemodynamic changes after interventional procedures. Transesophageal echocardiography is a new important guiding and monitoring technique during interventional cardiac catheterization procedures in children. It can provide additional real time imaging information, immediate identification of complications and assessment of hemodynamic changes.

Adolescent↗
PubMed1991

One stage repair of aortic arch anomalies and intracardiac defects.

Between August 1985 and May 1990, 27 neonates and infants underwent combined correction of intracardiac and aortic arch anomalies through a median sternotomy. Coarctation (CoA) was combined with VSD (6), AVSD (2), Taussig-Bing (TB) heart (5), transposition of the great arteries (TGA) (1), TGA + VSD (2), congenitally corrected TGA + VSD (1) and VSD + myxoid stenotic outlet valves (1). Interrupted aortic arch (IAA) was combined with VSD (10) and TB heart (1). Two patients had IAA type B as well as CoA. Age at operation varied from 2 to 243 days with a mean age of 51 days. Twenty patients (70%) were younger than 30 days. One TGA + VSD and all TB hearts had maligned outlet septum and right ventricular outflow tract obstruction (RVOTO). Posterior outlet septum deviation and left ventricular outflow tract obstruction (LVOTO) occurred in 8 patients with malalignment VSD and IAA (7) or CoA (1). Aortic arch reconstruction was performed using extended end-to-end anastomoses. In 3 patients, arch hypoplasia necessitated patch implantation. VSDs were closed through the right atrium unless the anatomy dictated otherwise. One TB heart was reconstructed with a Kawashima procedure. All other TB hearts and all TGAs were corrected with arterial switch operation. Obstructing outlet septum was resected whenever necessary. Follow-up was complete and included echo-Doppler control. Eleven patients had postoperative heart catheterisation. Early mortality was 18.5% (5 patients). Persisting LVOTO or RVOTO was responsible. There was no late mortality. Five patients were reoperated upon: 3 for stenotic anastomoses and 2 for a subaortic membranous stenosis. Successful balloon dilatation of recoarctation was performed four times.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1990

Streptokinase treatment for femoral artery thrombosis after arterial cardiac catheterisation in infants and children.

Data on 205 children who underwent retrograde arterial catheterisation were studied to assess the frequency of femoral artery thrombosis and the safety and efficacy of systemic streptokinase treatment for this complication. In 29 (14%) a transarterial balloon dilatation was performed. In 15 (7.3%) patients impaired arterial perfusion due to vascular spasm with or without thrombus formation was seen in the cannulated leg after catheterisation. Despite heparinisation, signs of impaired arterial circulation persisted in nine patients (4.4% of the total). In these patients femoral artery thrombosis was strongly suspected. Six (53%) of these had undergone a balloon dilatation. Therefore in this study the risk of femoral artery thrombosis developing was 12 times greater after transarterial balloon dilatation than after arterial catheterisation without dilatation (20.6% v 1.7%). Systemic infusion of streptokinase was started in all patients with femoral artery thrombosis. Arterial perfusion became normal in all patients, though in one this was delayed. Haematological monitoring showed lengthening of the thrombin time and a decrease of the fibrinogen concentration during streptokinase treatment. There were no serious complications. Systemic infusion of streptokinase is a safe and useful treatment in children with persistent femoral artery thrombosis after arterial cardiac catheterisation.

Cardiac Catheterization↗
PubMed1989

[Q-fever as a cause of myocarditis in childhood].

Q-fever occurs in The Netherlands in childhood more often than used to be believed. We treated an 8-month-old infant with congestive myocarditis associated with a seroconversion against Coxiella burnetii. The infection was probably caused by the father, who a few weeks earlier had visited his native Surinam, where he frequently was surrounded by domestic animals and drank raw cow's milk. After 2.5 years the child's general and cardial conditions are good although digoxin therapy is still necessary.

Antibodies, Bacterial↗