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P Ewert

Publications and source records attributed to P Ewert.

At least 19 recordsLinked to original sources
PubMed2006

Self-fabricated fenestrated Amplatzer occluders for transcatheter closure of atrial septal defect in patients with left ventricular restriction: midterm results.

To avoid left ventricular failure after transcatheter closure of atrial septal defects in elderly patients with restrictive left ventricular physiology, partial occlusion by fenestrated devices may be an option. If complete defect closure is not possible in these patients, significant reduction of left to right shunting usually results in clinical benefit. We report two patients in whom deterioration of left ventricular function could be avoided by implantation of self-fabricated fenestrated Amplatzer Septal Occluders (ASO) in patients with ongoing restrictive left ventricular physiology. We describe technical preparation of the standard occluder, the specific implantation technique, and the initial and the intermediate term results up to 24 months.

Aged↗
PubMed2006

Advantages of C2 monitoring to avoid acute rejection in pediatric heart transplant recipients.

BACKGROUND: Inadequate cyclosporine (CsA) blood levels are a major risk factor for acute rejection in transplant recipients. The CsA trough level (C0 level) measured just before the next dose is commonly used to adjust the oral dosage. However, the 2-hour post-CsA dose concentration (C2 level) is favored as the best single-point correlate of CsA area-under-the-curve concentration and may better reflect the immunosuppressive effect of CsA. Because an adequate C2 level has not yet been defined, this study was performed to assess the value of C2 monitoring for the prevention of acute rejection and to define target levels in pediatric heart transplant recipients. METHODS: C2 levels were assessed in 50 pediatric heart transplant patients with oral CsA therapy and compared with trough C0 levels using full blood sampling, mass spectrometry and a blinded analysis. Acute graft rejection was detected using intramyocardial electrocardiogram (IMEG) and serial conventional and tissue Doppler echocardiography (TDE). Rejection was confirmed or excluded by endomyocardial biopsy. RESULTS: C2 and not C0 levels were significantly reduced in patients with acute graft rejection (ISHLT Grade > or =2). Patients with a C2 level <600 ng/ml had a significantly higher risk of developing acute rejection (100% sensitivity and 82% specificity). Patients with impaired CsA absorption were identified with C2 monitoring and switched to another calcineurin inhibitor. CONCLUSIONS: Monitoring of the C2 rather than the C0 level better reflects immunosuppressive efficiency and identifies patients at increased risk of acute rejection. A C2 level of >600 ng/ml should be the target to prevent acute rejection.

Adolescent↗
PubMed2006

First experience with an oral combination therapy using bosentan and sildenafil for pulmonary arterial hypertension.

BACKGROUND: New oral substances such as beraprost, bosentan and sildenafil have proven effective in different forms of pulmonary arterial hypertension (PAH), both alone and in combination with standard treatment such as intravenous and inhaled prostacyclins. However, there are few reports so far on the effect of a combination of exclusively oral substances. In this paper, we present our initial findings of treatment using a combination of these oral substances in a heterogeneous group of patients with different forms of PAH. MATERIALS AND METHODS: Eleven patients with a median age of 12.9 years (5.5-54.7 years) with both idiopathic PAH and forms associated with congenital cardiac defects (PAH-CHD) with a mean pulmonary arterial pressure > 25 mmHg were enrolled in an observational, open-label, prospective, single-centre study. Either combination treatment with bosentan and sildenafil was started initially, or an existing bosentan treatment was complemented with sildenafil given as an add-on therapy. Mean doses given were 2.3 +/- 0.6 mg kg(-1) for bosentan and 2.1 +/- 0.9 mg kg(-1) for sildenafil. Clinical status, exercise capacity, and haemodynamics were assessed at baseline and at the end of the observation period after a mean follow-up time of 1.1 years (0.5-2.5 years). RESULTS: No major side effects regarding liver function and blood pressure regulation were noted. One patient died of sudden death elsewhere. Most patients were in New York Heart Association (NYHA) functional class III. Clinical improvement was about one NYHA class (mean 2.8 +/- 0.4-1.6 +/- 0.8, P = 0.001), which was associated with an increase of transcutaneous oxygen saturation (89.9 +/- 9.9-92.3 +/- 7.1%; P = 0.037), maximum oxygen uptake (18.1 +/- 6.8-22.8 +/- 10.4 mL kg(-1) x min; P = 0.043), and 6-minute walking distance (351 +/- 58-451 +/- 119 m; P = 0.039). Mean pulmonary arterial pressure measured invasively decreased (62 +/- 12-46 +/- 18 mmHg; P = 0.041). CONCLUSIONS: In our patient group, a combination of oral bosentan and sildenafil proved to be safe and effective. Clearly, randomized, double-blind, placebo-controlled studies are warranted to define the role and type of combination therapies in PAH.

Administration, Oral↗
PubMed2005

Left ventricular conditioning in the elderly patient to prevent congestive heart failure after transcatheter closure of atrial septal defect.

Transcatheter closure of atrial septal defects (ASDs) is a safe and effective treatment. Over the past years, an increasing number of elderly patients (age > 60 years) have been admitted for transcatheter closure to prevent ongoing congestive heart failure from volume overload. However, recent data point to the risk of serious acute left ventricular dysfunction leading to pulmonary edema immediately after surgical or transcatheter ASD closure in some patients. In this study, we used a technique described before to recognize in advance patients at risk of left heart failure after ASD closure. Those patients at risk were then treated with preventive conditioning medication for 48-72 hr before definitive transcatheter ASD closure was performed. Fifty-nine patients aged over 60 years (range, 60-81.8 years; median, 68 years) were admitted to our institution for transcatheter closure of an atrial septal defect. All patients received evaluation of atrial pressures before and during temporary balloon occlusion of the ASD. Patients with left ventricular restriction due to increased mean atrial pressures (> 10 mm Hg) during ASD occlusion received anticongestive conditioning medication with i.v. dopamine, milrinone, and furosemide for 48-72 hr before definitive ASD closure with an Amplatzer septal occluder was performed. In 44 patients without any signs of left ventricular restriction, ASD closure was performed within the first session. Fifteen (25%) out of 59 patients showed left ventricular restriction. In the majority of patients with LV restriction, the mean left atrial pressures with occluded ASD were significantly decreased after 48-72 hr of conditioning medication. Definitive ASD closure was then performed in a second session. Only two patients received a fenestrated 32 mm Amplatzer occluder due to persistent increased atrial pressures > 10 mm Hg even after conditioning medication. There were no significant differences in shunt, device size, or defect size between the two groups. Balloon occlusion of atrial septal defects identifies patients with left ventricular restrictive physiology before ASD closure. Intravenous anticongestive conditioning medication seems to be highly effective in preventing congestive heart failure after interventional closure of an ASD in the elderly patient with a restrictive left ventricle.

Aged↗
PubMed2005

Rare case of pulmonary arteriovenous fistula simulating residual defect after transcatheter closure of patent foramen ovale for recurrent paradoxical embolism.

We report on a patient suffering from recurrent cerebrovascular events despite previous transcatheter closure of persistent foramen ovale (PFO) with a Helex occluder. There was evidence of persistent left-to-right atrial shunt shown by transesophageal contrast echocardiography and the patient was admitted to our institution for interventional closure of the supposed residual defect. However, the PFO was completely closed by the device and left pulmonary artery injections showed a pulmonary arteriovenous fistula in the left lower lobe. This rare malformation may well explain the recurrent paradoxical embolism. Transcatheter fistula closure with coils was performed successfully. This case underlines that the existence of an isolated pulmonary arteriovenous fistula as a right-to-left shunt in patients with cryptogenic stroke should not be overlooked, even if a PFO is present and pulmonary arteriovenous fistula is not suggested by the initial physical findings or chest X-ray.

Adult↗
PubMed2005

Assessment of myocardial function of the systemic right ventricle in patients with D-transposition of the great arteries after atrial switch operation by tissue Doppler echocardiography.

INTRODUCTION: The long-term follow-up of patients with D-transposition of the great arteries after atrial switch operation shows specific problems such as tricuspid valve insufficiency, rhythm disturbances and failure of the morphologic right ventricle in systemic position. Assessment of the myocardial contractility of the subaortic right ventricle by conventional echocardiography is limited. The usage of tissue Doppler echocardiography with strain combined with strain rate imaging provides a new approach for quantitative analysis of longitudinal myocardial function. The aim of this study was to assess patterns of wall motion and regional contractile function of the systemic right ventricle in patients after atrial switch operation for D-transposition of the great arteries and to compare them to those of normal subjects. PATIENTS AND METHODS: Twenty-four patients with Dtransposition of the great arteries after atrial switch operation with a mean age of 21.3 (range, 13 to 31) years and a postoperative period of 16.9 years were examined and compared to 22 control individuals with a mean age of 21.5 (range, 3 to 43) years. Tissue Doppler studies were obtained from apical 4- chamber view to determine regional systolic (Syst(T)) and diastolic (E(T), A(T)) velocities as well as E(T)/A(T) ratio at the basal free wall. The presystolic isovolumic contraction peak was assessed and the ratio of the presystolic peak velocity to the isovolumic acceleration time as the IVA index was calculated. Strain and peak systolic and diastolic strain rates were assessed on basal, middle and apical segments of the right ventricular free wall. Data obtained from the morphologic right systemic ventricle in patients were compared to those derived from the left and the right ventricle in controls. RESULTS: The right ventricular free wall systolic velocities were significantly reduced in patients compared to velocities obtained from the normal right and left ventricle. On the other hand, the IVA index was only reduced in patients compared to the IVA index in the normal subpulmonary right ventricle. Compared to data obtained from the normal systemic left ventricle, the IVA index in patients was not significantly different. In contrast, strain and strain rate parameters in all analyzed segments mostly showed a highly significant reduction compared to normal right and left ventricular data. CONCLUSION: Tissue Doppler echocardiography is a promising tool for the evaluation of regional myocardial contractile function of the morphologic right systemic ventricle in patients following atrial switch operation for D-transposition of the great arteries. Presystolic, systolic and diastolic regional ventricular function was reduced in the systemic right ventricle. However, further comparative studies using other quantitative parameters of global and regional myocardial function derived from cardiac catheterization or MRI should be performed in order to evaluate the reliability of tissue Doppler echocardiography for the assessment of global right ventricular function in these patients.

Adolescent↗
PubMed2005

Initial experience with bosentan (Tracleer) as treatment for pulmonary arterial hypertension (PAH) due to congenital heart disease in infants and young children.

INTRODUCTION: Bosentan, a dual endothelin-receptor antagonist, has been shown to be an effective treatment option in patients with the idiopathic form of pulmonary arterial hypertension (PAH). We used bosentan as compassionate treatment in infants and young children with congenital heart disease (CHD) who had a) PAH preoperatively representing a contraindication to corrective surgery or b) persisting PAH after corrective surgery causing right heart failure and reduced exercise tolerance. METHODS: Seven children with PAH due to CHD (median age 3.8 years; range 1.5 to 6.4 years) received 3 mg/kg/d bosentan (Tracleer) orally. Clinical, echocardiographic and hemodynamic parameters were measured and laboratory tests performed before treatment and during steady state while on treatment. Routine liver function parameters were monitored monthly. RESULTS: Mean bosentan treatment time was 8.6+/-5 months. During bosentan therapy there were no significant adverse events. The clinical status remained stable or improved in all patients: NYHA class decreased from 2.6+/-0.6 to 1.7+/-0.6 (p<0.05). This was associated with a mean reduction of the right ventricular systolic pressure (RVSP) from 96+/-11 mmHg to 71+/-26 mmHg (p<0.05). CONCLUSIONS: Treatment with bosentan in infants and young children with PAH due to congenital heart disease was tolerated without significant side effects and resulted in stabilization of clinical status. A significant reduction in right ventricular systolic pressure (RVSP) could be demonstrated. These results suggest that the dose regimen used is appropriate and safe for the treatment of infants and children with PAH, resulting in a reduction of pathologically increased pulmonary vascular resistance.

Antihypertensive Agents↗
PubMed2005

Analysis of atrial and ventricular performance by tissue Doppler imaging in patients with atrial septal defects before and after surgical and catheter closure.

OBJECTIVE: To compare the effects of surgical and device closure of atrial septal defects on atrial and ventricular performance assessed by the novel tissue Doppler derived strain rate. BACKGROUND: Despite the increasing number of transcatheter closures, there is no information comparing the effect of the transcatheter closure technique on atrial performance with that of conventional surgery. Tissue Doppler derived strain rate can effectively quantify local myocardial function independent of the overall heart motion. DESIGN AND PATIENTS: Twenty-four patients [aged 21.5 (6-70) years] with isolated atrial septal defect of the secondum type before and 1 week after surgical (n = 12) or Amplatzer Septal Occluder closure (n = 12) and 30 healthy controls [aged 26.0 (2-58) years] were studied. Atrial and ventricular strain rate curves were assessed in the middle of their corresponding lateral walls in an apical four-chamber view. The systolic, early diastolic, and late diastolic strain rates peaks were measured. RESULTS: Compared to preclosure condition, the right atrial late diastolic (P < 0.01), right ventricular systolic (P < 0.01), right ventricular early diastolic (P < 0.01), and left atrial late diastolic peak (P < 0.01) strain rates were reduced after surgery but not after Amplatzer Septal Occluder closure. The LV parameters did not significantly differ before and after atrial septal defect closure by either technique. CONCLUSIONS: In contrast to surgery, transcatheter closure of atrial septal defect preserves atrial and right ventricular function. Tissue Doppler derived strain rate can be applied to provide quantitative analysis of regional atrial and ventricular performance.

Adolescent↗
PubMed2005

Magnetic resonance imaging guided catheterisation for assessment of pulmonary vascular resistance: in vivo validation and clinical application in patients with pulmonary hypertension.

OBJECTIVES: To validate in vivo a magnetic resonance imaging (MRI) method for measurement of pulmonary vascular resistance (PVR) and subsequently to apply this technique to patients with pulmonary hypertension (PHT). METHODS AND RESULTS: PVR was assessed from velocity encoded cine MRI derived pulmonary artery (PA) flow volumes and simultaneously determined invasive PA pressures. For pressure measurements flow directed catheters were guided under magnetic resonance fluoroscopy at 1.5 T into the PA. In preliminary validation studies (eight swine) PVR was determined with the thermodilution technique and compared with PVR obtained by MRI (0.9 (0.5) v 1.1 (0.3) Wood units.m2, p = 0.7). Bland-Altman test showed agreement between both methods. Inter-examination variability was high for thermodilution (6.2 (2.2)%) but low for MRI measurements (2.1 (0.3)%). After validation, the MRI method was applied in 10 patients with PHT and five controls. In patients with PHT PVR was measured at baseline and during inhalation of nitric oxide. Compared with the control group, PVR was significantly increased in the PHT group (1.2 (0.8) v 13.1 (5.6) Wood units.m2, p < 0.001) but decreased significantly to 10.3 (4.6) Wood units.m2 during inhalation of nitric oxide (p < 0.05). Inter-examination variability of MRI derived PVR measurements was 2.6 (0.6)%. In all experiments (in vivo and clinical) flow directed catheters were guided successfully into the PA under MRI control. CONCLUSIONS: Guidance of flow directed catheters into the PA is feasible under MRI control. PVR can be determined with high measurement precision with the proposed MRI technique, which is a promising tool to assess PVR in the clinical setting.

Adult↗
PubMed2005

The CP stent--short, long, covered--for the treatment of aortic coarctation, stenosis of pulmonary arteries and caval veins, and Fontan anastomosis in children and adults: an evaluation of 60 stents in 53 patients.

OBJECTIVE: To evaluate the feasibility and usefulness of the Cheatham platinum (CP) stent in a broad spectrum of lesions. METHODS: Retrospective analysis of 60 implanted CP stents (11-80 mm lengths, 12 covered) between September 2001 and March 2004. PATIENTS: 53 patients aged 2.5-68 years (median 17 years). Body weight ranged from 12-95 kg (median 52 kg). Thirty six patients had aortic (re)coarctation; seven of them had functionally interrupted aortic arches. Thirteen patients had pulmonary artery stenosis and four had stenosis of caval veins or conduits in a total cavopulmonary connection (TCPC). RESULTS: Arterial pressure gradients dropped from 33 mm Hg (range 20-80 mm Hg) to 5 mm Hg (range 0-10 mm Hg) and pressure gradients in TCPC or caval veins dropped from 4 mm Hg (range 4-20 mm Hg) to 0 mm Hg (range 0-3 mm Hg). All stents were placed in the target lesion without complications. Three stent fractures without clinical instability were noted. CONCLUSIONS: The CP stent is suitable for the treatment of vessel stenosis in congenital heart diseases from childhood to adulthood. Whether these good results will be stable in the long term needs to be investigated.

Adolescent↗
PubMed2004

[Levosimendan-long-term inodilation in an infant with myocardial infarction].

An infant with myocardial infarction due to congenital stenosis of the left coronary artery with consecutive left ventricular dysfunction and mitral regurgitation developed refractory pulmonary hypertension (PHT) and recurrent PHT crises. Catecholamines to support cardiac function, or pulmonary vasodilators like inhaled nitric oxide showed no effect. Treatment with Levosimendan (Simdax), a new inodilator, combining both inotropic and pulmonary vasodilating effects, improved left ventricular dysfunction, increased cardiac index, decreased pulmonary vascular resistance and reduced frequency and extent of the PHT crises. This case may suggest the use of Levosimendan as a long-term inotropic agent and pulmonary vasodilator in children with depressed cardiac function.

Cardiac Output, Low↗
PubMed2004

[Transcatheter closure of congenital ventricular septal defects].

We report on the transcatheter closure of ventricular septal defects (VSD) in 26 patients with Amplatzer Occluders and Nit- Occlud Coil Systems. Twenty-one patients had a perimembranous and 5 patients a muscular VSD. Patients' age range was 5 months to 59 years (median 8 years) and their body weight 4.5 kg to 167 kg (median 28 kg). Defect diameters were 3-11 mm (median 5 mm). Sixteen patients had left ventricular volume overload and 7 patients pulmonary hypertension (median 50% of systemic pressure). Seven patients suffered from trivial or mild aortic regurgitation. Twenty-eight devices (4-12 mm; median 8 mm) were implanted (16 Amplatzer, 12 Nit-Occlud) through sheaths of 4F to 9F (median 7F). Fluoroscopy times were 8.3- 56.5 min (median 26.2 min). One coil was surgically explanted directly after intervention. One patient needed pulmonary banding due to additional VSDs. After a follow-up of 7 months (1-12 months), 2 patients had a small and 9 a minimal residual shunt. Thirteen defects were completely closed. Transcatheter closure of VSDs with new devices seems to be a promising therapy for suitable defects in different hemodynamic conditions in patients of every age.

Adolescent↗
PubMed2003

[Stent implantation as therapy of first choice in adults with coarctation].

Stent implantation for coarctation of the aorta is an alternative to surgery or balloon dilation. We report our results in 12 patients with a median age of 22 years (10 to 28 years) and a body weight of 60 kg (32 to 97 kg). Nine patients had native stenosis and three had recoarctation after surgery. Invasively measured systolic pressure gradients ranged from 20 to 100 mmHg. Nine patients suffered from brachiocephalic hypertension. Eleven implantations were successful with a median dilatation of 17 mm (15-25 mm). Residual gradients were 0-5 mmHg in seven patients, 5-10 mmHg in three and 15 mmHg in one patient with postoperative recoarctation. Twenty-one months (2-37 months) after intervention, no hemodynamically relevant intimal proliferations, no restenosis, and no aneurysms were present. Thus, stent implantation is a very promising therapy for coarctation of the aorta in adults and is on its way to becoming the therapy of first choice.

Adolescent↗
PubMed2003

[Ebstein's anomaly: long-term results after modified reconstruction of tricuspid valve without ventricle plication].

Ebstein's anomaly is a rare congenital heart defect in which the hinges of the septal and/or posterior leaflets are displaced downward to the right ventricle. The anterior leaflet is usually not displaced but is enlarged and sail-like and valve closure is likewise displaced downwards. Since 1988 we have operated on 22 patients with Ebstein's anomaly using a modified repair technique of the tricuspid valve. This technique restructures the valve mechanism at the level of the true tricuspid annulus by using the most mobile leaflet for valve closure without plication of the atrialized chamber. We evaluated our long-term results with regard to functional capacity (New York Heart Association functional class), tricuspid valve function, rhythm disturbances and re-operation rate. We quantified the right ventricular function by measuring flow velocity integral of the pulmonary artery (VTIPA). All patients survived the operation. There were two hospital deaths (9%) and the late mortality was 4.5%. The mean followup period was 9 years (range, 1.5 to 13 years) for 19 patients. So far no re-operation has been necessary. Preoperatively, the majority of all patients were in NYHA classes III and IV (79%). After the first postoperative follow-up examination (2.9 months), 17 patients were in NYHA class II. Long-term follow-up examinations showed an additional improvement of 11 patients to NYHA class I. Echocardiographic studies demonstrated a significant improvement of tricuspid valve function. No tricuspid valve stenosis was observed. Significant improvement of VTI(PA) was observed. Analysis of the postoperative deaths demonstrated that all patients were in NYHA class III or IV and had a cardiothoracic ratio of 0.65 or more. A severe reduction in functional capacity seems to be an additional risk factor for mortality beside a cardiothoracic ratio greater than 0.65. We conclude that reconstruction of the tricuspid valve without ventricle plication not only achieves good functional results immediately after the operation but that follow-up examinations demonstrate stable or improved functional capacity in the long term. We postulate that incorporation of the atrialized chamber into the right ventricle may contribute to right ventricular contraction and thereby account for the improved functional capacity of the patients.

Adolescent↗
PubMed2003

Early and medium-term results after modified Fontan operation in adults.

OBJECTIVE: Single ventricle palliation is rarely performed in adults and the results are less optimal than in children. In this article we analyze our experience with the modified Fontan operation in this age group. METHODS: Data of 15 consecutive patients with single ventricle with a mean age of 26 (range 16-38) years, who underwent Fontan operation between 3/92 and 1/2000 were retrospectively analyzed. Five patients had previously had an aortopulmonary shunt in childhood and two patients had previously received a bi-directional cavopulmonary shunt as adults. Eleven patients were preoperatively in NYHA class III and four in class II. The main factors for the selection of the patients before surgery were well-developed pulmonary arteries with lower lobe index 120+30 mm/m(2), pulmonary artery pressure <18 mmHg, good cardiac function and enddiastolic systemic ventricular pressure <12 mmHg. The lateral tunnel Fontan operation (LTFO) was performed in ten patients and extracardiac Fontan operation (ECFO) in five. A fenestration 4-5 mm in size was constructed in all patients with LTFO and in three of five patients with ECFO. RESULTS: There was one intraoperative and one late death (total mortality 13%). The mean extubation time and hospital stay were 24 h and 21 days, respectively. Severe postoperative complications were observed in three patients (20%). Two LTFO patients out of a total of eight patients (53%) with perioperative arrhythmias received a permanent pacemaker due to bradyarrhythmia. During the median follow-up of 5.0 (range 2.3-10.1) years, four patients developed arrhythmias; one of them had new onset bradyarrhythmia after LTFO and required permanent pacemaker implantation. The median postoperative oxygen saturation was 93% (range 90-98%). NYHA class improved significantly in 12 survivors. Cardiac catheterization (0.5-4 years postoperatively, n=12) showed excellent Fontan hemodynamics in all patients. CONCLUSIONS: The modified Fontan operation can be performed in adults with acceptable early and midterm mortality and morbidity and leads to either complete or marked relief of cyanosis and enhanced exercise tolerance in all survivors. Postoperative arrhythmias are one of the main drawbacks but the incidence of arrhythmias after ECFO seems to be lower. The long-term follow-up has yet to be established.

Adolescent↗
PubMed2003

Antibradycardia pacing in patients with congenital heart disease: experience with automatic threshold determination and output regulation (Autocapture).

AIMS: The purpose of this study was to reevaluate whether St Jude Medical's Autocapture algorithm (AC) with beat-to-beat capture confirmation, automatic pacing threshold determination and output adjustment can be applied to paced patients with congenital heart disease (CHD). METHODS AND RESULTS: 30 patients with CHD received a transvenous (group A: n=22) or epicardial (group B: n=8) single (n=7) or dual chamber (n=23) AC pacemaker for antibradycardia pacing. As a safe AC function is ensured only if a sufficient evoked response (ER) and a low lead polarization amplitude (LPA) are present, these parameters were reevaluated from 112 follow-up studies with respect to AC-function. In all but one transvenous system AC correctly functioned. AC was recommended in 5/8 patients with epicardial leads but correct AC function was preserved in only 3 patients. CONCLUSION: These data suggest that the application of the AC algorithm is safe in patients with CHD when transvenous leads are used. Whether appropriate AC function is possible with epicardial leads needs individual verification.

Adolescent↗