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P Ewert

Publications and source records attributed to P Ewert.

At least 19 recordsLinked to original sources
PubMed2001

Masked left ventricular restriction in elderly patients with atrial septal defects: a contraindication for closure?

The impact of an atrial septal defect in the elderly with reduced diastolic elasticity of the left ventricle is unclear. We studied the hemodynamic changes during balloon occlusion of atrial septal defects in patients over 60 years of age. In 18 patients (61-78 years old; median, 70), the left atrial pressure and the mitral valve inflow was measured during complete balloon occlusion of the defect and after deflation of the balloon. In seven patients, the left atrial pressure and the E/A ratio of the mitral valve inflow increased markedly (P = 0.02). Mean atrial pressures reached values of 27 mm Hg and the v-wave peak values of 55 mm Hg. Two patients received a transcatheter device closure and developed congestive heart failure. In the elderly, an atrial septal defect can have a decompressive impact on the left ventricle. Therefore, caution appears to be warranted if atrial septal closure is planned.

Aged↗
PubMed2001

[Acute left heart failure after interventional occlusion of an atrial septal defect].

Congestive left ventricular failure after surgical closure of an atrial septal defect (ASD) has been repeatedly reported, particularly in the elderly. We present a case of left ventricular failure after a successful transcatheter closure of an ASD, which to our knowledge has not been described before. In a 78-year-old woman (50 kg, 160 cm) with well-preserved left ventricular function (ejection fraction 65%) and without coronary artery disease or arterial hypertension, an ASD (Qp/Qs 1.6:1) was closed with an Amplatzer Septal Occluder without a residual shunt. Two hours after the procedure, she developed pulmonary edema due to left ventricular failure (increase of end-diastolic diameter from 42 mm to 54 mm, ejection fraction 20%), had to be mechanically ventilated for 24 hours and needed catecholamines for 4 days. High doses of diuretics were supplied until the ejection fraction normalized (32%). The patient could not be discharged until two weeks after intervention. A reduced preload for decades may predispose acute left ventricular failure, particularly in the elderly with compromised ventricular compliance.

Aged↗
PubMed2001

Feasibility of transcatheter closure of multiple defects within the oval fossa.

BACKGROUND: Multiple perforations in the floor of the oval fossa may be an obstacle for transcatheter closure. Thus, we analyzed the interventions in 33 patients with more than one interatrial communication in comparison with 370 procedures with a single defect. METHODS AND RESULTS: A diagnostic catheterization, which included a balloon-sizing maneuver, was performed. We implanted a total of 46 occluders, made up of 42 Amplatzers and 4 CardioSEALs. In 20 patients, the defects were closed with a single occluder, namely 18 Amplatzer and 2 CardioSEAL devices. Complete closure was achieved in 15 patients, while a tiny residual shunt remained in 5 patients. In 13 patients, two devices were implanted, without any residual shunt being found immediately after implantation. In 3 patients, the occluders did not touch each other. In 10 patients, their rims overlapped. In comparison with the control group, the group with multiple defects did not differ in the distribution of age, gender, and indications for device closure. The mean time of the procedure, and the time required for fluoroscopy, however, were significant longer (P<0.001). These times ranged from 45 to 250 minutes with a median of 140 minutes, and from 0.0 to 39.2 minutes, with a median of 12.0 minutes, respectively. Also, the association with an atrial septal aneurysm was significantly more frequent (61 vs. 17%; P<0.001). The times taken during insertion of double devices were also significantly longer than those needed for insertion of a single device (P<0.001). CONCLUSIONS: Transcatheter closure of multiple defects within the oval fossa is feasible with currently available occluders, albeit than, in selected cases it is necessary to implant two devices.

Adolescent↗
PubMed2001

Hemorheology and renal function during cardiopulmonary bypass in infants.

BACKGROUND: Acute renal failure is an occasional complication after cardiopulmonary bypass in infants. Whereas it is well known that postoperative hemodynamics inflict acute renal failure, the influence of extracorporeal circulation on the kidney is less clear. Moreover, changes in blood viscosity occur during and after surgery, which may influence renal dysfunction. For this reason, we investigated the impact of blood viscosity on renal function during cardiopulmonary bypass. METHODS: In 34 patients weighting less than 10 kg, we performed repeated analysis of urine, blood, and plasma viscosity. RESULTS: Polyuria and proteinuria that appeared during cardiopulmonary bypass indicated an elevated transglomerular filtration gradient, which recovered within 24 hours. The appearance of N-acetyl-beta-D-glucosaminidase in the urine, and elevated excretion of sodium, were additionally indicative of mild tubular damage. Elevation of blood viscosity during hypothermic perfusion showed a statistical correlation with proteinuria and N-acetyl-beta-D-glucosaminidaseuria. With hypothermia, the relation of blood viscosity to plasma viscosity became stronger, while the relation to the hematocrit decreased compared to normothermia. CONCLUSIONS: During cardiopulmonary bypass perfusion, the kidney can be stressed by proteinuria and mild tubular damage. Our data provide evidence that the kidneys can be protected by improved blood viscosity during cardioplegia, but this needs confirmation in a prospective interventional study.

Acetylglucosaminidase↗
PubMed2001

[Options for interventional heart catheterization in congenital heart disease].

Parallel to the rapid advances in the surgical options in treating congenital heart defects pioneering innovations in interventional cardiology could establish alternative treatment to surgery for these patients. On the one hand there is a trend to interventionally cure simple heart defects, but on the other hand interventional procedures can often only support surgical treatment. This review gives a limited overview over the recent possibilities and problems of the interventional cardiology and therefore focuses on balloon dilatation of congenital valve or vessel stenoses, on device closure of intracardiac defects and on the implantation of stents for the enlargement of elastic or long stenoses.

Angioplasty, Balloon, Coronary↗
PubMed2001

A rare complication of laparoscopic surgery: iatrogenic arteriovenous fistula with high-output cardiac failure.

SUMMARY: The authors report a 19-year-old man with cardiomegaly and high-output cardiac failure resulting from a hemodynamically significant arteriovenous fistula that was diagnosed 18 months after laparoscopic surgery for an inguinal hernia. The diagnosis was established on clinical examination and by ultrasonography and was confirmed by cardiac catheterization and angiography. The fistula was closed surgically by direct venous suture and reconstruction of the iliac artery with a polytetrafluoroethylene patch. The surgical repair achieved complete closure of the fistula with rapid normalization of cardiac size and function within 8 days.

Adult↗
PubMed2000

Transcatheter closure of atrial septal defects without fluoroscopy: feasibility of a new method.

BACKGROUND: In an effort to reduce x-ray exposure, we developed a technique for transcatheter closure of atrial septal defects under echocardiographic guidance without fluoroscopy. To assess the efficiency of this procedure for routine use, we compared our initial results with those for the conventional procedure. METHODS AND RESULTS: Twenty-two randomly selected patients (median age 18 years; range 2 to 66 years) with atrial septal defects (n=13) or patent foramen ovale (n=9) underwent cardiac catheterization for possible interventional defect closure with echocardiography as the only imaging tool. Median stretched diameter was 9 mm (range 6 to 26 mm); median left-to-right shunt over the atrial septal defects was Qp/Qs=1.8 (range 1.5 to 2.6). An Amplatzer septal occluder was successfully implanted in 19 defects without fluoroscopy and in 3 with the help of radiography. After 1 month, complete defect closure was documented in all patients. Compared with the conventional procedure of a control group of 131 patients, procedure times were not significantly different (88 versus 100 minutes; P=0.09). However, the study group received significantly higher doses of propofol for sedation (9.9 versus 5.6 mg/kg body weight; P=0.002) owing to extended transesophageal echocardiography. CONCLUSIONS: In the majority of patients in whom transcatheter closure of interatrial communications with the Amplatzer septal occluder is possible, the procedure can be safely performed under echocardiographic guidance without fluoroscopy.

Adolescent↗
PubMed2000

[Interventional occlusion of atrial septum defects larter than 20 mm in diameter].

UNLABELLED: Over the last few years, various devices for the interventional closure of atrial septal defects (ASD) up to a diameter of 20 mm have been developed. We report our clinical experience in closing ASD with a diameter larger than 20 mm diameter with the Amplatzer Septal Occluder (ASO). METHOD: The stretched diameter of the ASD was measured by inflating a sizing balloon within the defect until an indentation in the circumference in the balloon could be observed. An ASO with a stent diameter 2-4 mm larger than the indentation in the circumference of the balloon was chosen and implanted via 9-12 French sheaths. In contrast to the closure of smaller defects, pullback of the device onto the atrial septum was only performed when the connecting stent of the ASO was completely deployed in order to achieve maximal centering characteristics and optimal support of the retention skirt of the left atrial disc on the edges of the defect. Only then was the right atrial disc deployed and actively configured by advancing the sheath and the delivery cable against the atrial septum. Implantation was only attempted if the atrial septal rims (except the anterior rim around the aorta) measured more than 7 mm by echocardiography to avoid injury or disturbance of sensitive intracardiac structures. After placement, the fixation of the device and the mechanical stability was proven by an extensive "Minnesota wiggle". The ASO was released only when TEE showed no or a trivial residual color flow through the connecting stent; otherwise repositioning was performed. RESULTS: Out of 352 patients (P) with successful closure of interatrial defects, 70 P (age: 1.1-77.3 years) had stretched defects larger than 20 mm diameter (median 22 mm diameter (20-36), 25/75% quartiles = 20/26 mm). Mean shunt size was Qp:Qs 2.1:1 (0.7-3.9:1), mean fluoroscopy time 10.9 min (0-63). Complete closure could be achieved in 85.7/93.1/100% after 3 months, 1 and 2 years, respectively. Besides 3 P with persistent atrial fibrillation, only 5 P showed transient atrial tachyarrhythmias, 2 only periprocedural and 3 within the first 3 months after implantation were treated with beta-blocker. In one patient, an acute embolization of the device occurred because a diminished posterior rim was not visualized by a monoplane TEE probe necessitating surgical explantation and defect occlusion. Despite oversizing the device, no "mushrooming" misconfiguration were observed. CONCLUSION: Transcatheter closure of large atrial septal defects with the Amplatzer Septal Occluder is feasible, safe and effective. Risk of complications do not seem to occur more frequently than after closure of smaller defects if one adheres to certain sizing and implantation measures. The incidence of transient atrial tachyarrhythmias seems to be low.

Adolescent↗
PubMed2000

[Interventional treatment of congenital heart defects in infants with a body weight up to 2,500 grams].

BACKGROUND: Pediatricians and neonatologists are still reluctant to consider invasive cardiological or cardiosurgical treatment in low body weight infants because it is believed to considerably increase the risk. The aim of this study was to assess the results and complications of percutaneous transcatheter interventions in infants with a weight below 2.5 kilograms. METHODS: Retrospective analysis was undertaken for all patients with a weight below 2.5 kilograms who underwent cardiac catheterization from 01/1994 to 04/1999. During this time 42 diagnostic catheterizations in 29 patients and 27 transcatheter interventions in 24 patients were performed. RESULTS: Surgery was replaced or effectively postponed in 9 (33%) out of 27 transcatheter interventions. This was possible for pulmonary stenosis, valvular aortic stenosis and aortic coarctation. A stabilization of the hemodynamic situation was possible in 14 patients. An antegrade pulmonary flow was established in 5, an effective interatrial shunt created in 5 and the arterial duct stented in 3 patients. Only 3 patients had no benefit from the intervention; however, there were no deaths nor hemodynamic complications. Arrhythmias occurred in 9% of all catheterizations and interventions but were transient in all cases. Femoral arterial complications were observed in 30% of all arterial catheterizations. CONCLUSION: Diagnostic cardiac catheterization and percutaneous transcatheter interventions can be performed with low mortality and acceptable morbidity in low weight infnats. Transcatheter interventions can replace surgery, postpone the necessity for surgery or stabilize the hemodynamic situation prior to surgery.

Birth Weight↗
PubMed2000

Optimal conduit size for extracardiac Fontan operation.

BACKGROUND: Lack of conduit growth potential and thrombogenicity are the main drawbacks of the extracardiac Fontan operation (ECFO). Optimal size of the conduit according to the patients age and inferior vena cava diameter has not been established. OBJECTIVES: We set out to ascertain whether the optimal dimensions of the conduit could be determined before an ECFO. METHODS: Actual and expected age-related inferior vena cava diameters were compared with the extracardiac conduit diameter in 20 patients after ECFO. In 50 other pediatric and adult patients, the distance between intrapericardial part of the inferior vena cava and the undersurface of the right pulmonary artery (IVC-RPA) was measured. Cases of conduit thrombosis were analyzed. RESULTS: The actual diameter of the inferior vena cava was variable and has a weak correlation with anthropometric data and expected diameter (R=0.07-0.23, P=0.32-0.76). The IVC-RPA distance correlated with height (R=0.87, P=0.0001), but was also variable. At the age of 2-4 years and body weight 12-15 kg IVC diameter and IVC-RPA distance are equal to 60-80% of adult values. Conduit thrombosis developed in two patients with unfavorable Fontan hemodynamics and oversized conduits. CONCLUSIONS: Considering the inferior vena cava size, ECFO may be performed at the age of 2-3 years and at a body weight 12-15 kg, when a hemodynamically optimal almost adult sized conduit can be implanted. Optimization of the conduit is necessary on the basis of the actual inferior vena cava diameter and IVC-RPA distance. Anticoagulation postoperatively should be considered to prevent conduit thrombosis in patients with suboptimal Fontan circulation

Adolescent↗
PubMed2000

Treatment of atrial septal defects in symptomatic children aged less than 2 years of age using the Amplatzer septal occluder.

AIMS: To assess results of closure of atrial septal defects within the oval fossa by devices delivered by catheterisation in symptomatic infants and children under 2 years of age. METHODS AND RESULTS: The Amplatzer septal occluder was used. Results, and complications of transcatheter device treatment in patients aged below 2 years were compared to previous results from our institution. PATIENTS: We attempted closure in 12 consecutive patients below the age of 2 years who presented with an atrial septal defect between May 1997 and 1999. Symptoms were failure to thrive in 6, frequent chest infections in 5, and the need for treatment of heart failure in the other. All were thought to have a defect suitable for interventional closure. The atrial defects were seen in isolation in 10 children, but 2 had associated pulmonary stenosis which had been treated by balloon dilation prior to placement of the Amplatzer occluder. RESULTS: The Amplatzer septal occluder was implanted at a mean age of 1.4 +/- 0.4, with a range from 0.8 to 1.8 years. Ratios of pulmonary-to-systemic flow had been 2.1 +/- 0.5, with a range from 1.6 and 3.2, and the defect was measured at 12 +/- 4 mms. Fluoroscopy time was 12.8 +/- 10.2 minutes, with a range from 5 to 43 minutes, and the time of the overall procedure was 162 +/- 70 minutes, with a range from 85 to 360 minutes. It proved necessary to remove the device in 2 patients (16%) because of a residual shunt and movement after release. One of these developed transient neurological complications. Both subsequently underwent surgical treatment. CONCLUSION: Symptomatic patients less than 2 years of age can undergo successful closure of an atrial septal defect using the Amplatzer device, but the rates of success are less, and procedure time longer, than in older children or adults.

Cardiac Catheterization↗
PubMed2000

[Pre- and postoperative evaluation of ventricular function, muscle mass and valve morphology by magnetic resonance tomography in Ebstein's anomaly].

PURPOSE: To evaluate the value of MRT with spin echo (SE) and CINE gradient echo (GE) sequences for the pre- and postoperative assessment of patients with Ebstein's anomaly. METHODS: Twelve patients within the ages of four to 49 years (mean 22 +/- 12 years) were examined pre- (n = 5) or postoperatively (n = 7) after tricuspid valve reconstruction with a 1.5 T scanner. For the anatomical assessment, an ECG-gated transverse SE-sequence, for the assessment of valve morphology and function as well as for volumetry a CINE GE-sequence with retrospective gating was used. With the use of the multislice-multiphase technique, after summing up the manually outlined epi- and endocardial areas, endsystolic (ESV) and enddiastolic volumes (EDV), ejection fraction (EF), stroke volume (SV), and muscle mass (MM) were calculated for both ventricles. RESULTS: The differentiation of the displaced parts of the tricuspid valve (TV) was insufficient with static SE, but was possible in all patients with CINE-MRT. Like in Doppler echocardiography, a qualitative assessment of tricuspid insufficiency was possible in CINE-MRT, the mean incompetence grade preoperative was 1.8 (+/- 0.8), postoperative 0.7 (+/- 0.5). The mean RV-EF in the preoperative group was 41.8% (+/- 6.4), in the postoperative group 47.9% (+/- 10.6), the mean LV-EF preoperative 47.4% (+/- 8.5%), postoperative 63.0% (+/- 9.4). CONCLUSION: CINE-MRT should rather be used than SE for the assessment of valve morphology. EF, muscle mass and tricuspid incompetence can also be calculated pre- and postoperative with CINE-MRT.

Adolescent↗
PubMed2000

Late-diastolic forward flow in the aorta induced by left atrial contraction.

Late-diastolic forward flow is a well-described phenomenon detectable by Doppler echocardiography in the pulmonary trunk. It is supported by a restrictive right ventricular diastolic function and by a low end-diastolic pulmonary artery pressure. A similar phenomenon for the left ventricle and the aorta has not been described. We report a case of a preterm infant with aortic stenosis and endocardial fibroelastosis, who underwent balloon valvuloplasty. Restrictive left ventricular diastolic filling led to high left atrial pressure (27 mm Hg) and a very pathologic ratio of early-to-late peak velocities (2.6) for an infant of 29 weeks' gestation. In combination with a low diastolic aortic pressure (24 mm Hg) caused by moderate aortic regurgitation after intervention, a late-diastolic forward flow was detectable in the aorta during left atrial contraction with pulsed Doppler echocardiography.

Aorta↗
PubMed2000

Diagnostic catheterization and balloon sizing of atrial septal defects by echocardiographic guidance without fluoroscopy.

To avoid x-ray exposure prior to interventional closure of atrial septal defects (ASDs), we recently developed a technique for diagnostic catheterization and balloon sizing of the defect by echocardiographic guidance without fluoroscopy. We report on our first experiences with this technique. Fourteen patients with atrial septal perforations (mean age, 23 years; range, 1-66 years) underwent diagnostic catheterization and balloon sizing prior to possible interventional defect closure. Mean size of the defects was 16 mm (7-29 mm). Mean left-to-right shunt was Qp/Qs = 2.0 (range, 1.0-4.0). Without fluoroscopy, the procedures were performed in two children by transthoracic echocardiography (TTE) and in 12 patients by both TTE and transesophageal echocardiography (TEE). Mean procedure time was 59 minutes (range, 35-90 minutes). We conclude that oxymetry, pressure recordings, and the estimation of the balloon-stretched size of atrial septal perforations can be performed safely by echocardiographic guidance without fluoroscopy. The x-ray exposure for patient selection prior to a transcatheter closure of an ASD can be avoided with this technique.

Adolescent↗
PubMed2000

Morphology of perforated atrial septal aneurysm suitable for closure by transcatheter device placement.

OBJECTIVE: To define the morphological criteria of perforated atrial septal aneurysms suitable for closure by a transcatheter device. METHODS: A retrospective analysis of all consecutive patients with atrial septal aneurysm and one or more perforations presenting between May 1997 and June 1999. The aneurysms were classified as: aneurysm with persistent foramen ovale (type A); aneurysm with single atrial septal defect (type B); aneurysm with two perforations requiring more than one device for closure (type C); and aneurysm with multiple perforations (type D). PATIENTS: Data from 50 patients aged 5-78 years (mean 43 years) were analysed; 32 had systemic thromboembolism or transient ischaemic attacks, eight presented with dyspnoea on exercise, and 10 were discovered incidentally but had significant left to right shunt and right ventricular volume overload. RESULTS: In all 18 patients with aneurysm and persistent foramen ovale (type A), transcatheter closure was possible. In nine with aneurysm and atrial septal defect (type B), five defects were closed and four required surgery. Device closure was achieved in all 10 patients with aneurysms and two perforations (type C), but four had a residual shunt. Thirteen patients with multiple perforated aneurysms (type D) underwent surgery. CONCLUSIONS: This classification of morphology of perforations of aneurysm is clinically useful for selecting patients for treatment by transcatheter devices.

Adolescent↗
PubMed1999

Transcatheter closure as standard treatment for most interatrial defects: experience in 200 patients treated with the Amplatzer Septal Occluder.

To judge whether an Amplatzer Septal Occluder can be used as standard therapy instead of surgery for closure of atrial septal defects we report our experiences in 200 patients. Of these patients, 127 had an atrial septal defect with haemodynamically significant left-to-right shunt, 68 patients a persistent oval foramen after presumed paradoxical embolism, and 5 had a fenestration after Fontan-repair. Mean age was 29.8 years (0.8 to 77.7 years). Body weight ranged from 6.9 to 120.0 kg (mean 51.5 kg). After diagnostic cardiac catheterization, and balloon-sizing of the defect, we implanted Amplatzer Septal Occluders with stents of 4 to 28 mm diameter. Follow-up studies were obtained after 48 hours, and one, six, and twelve months. Transcatheter closure of the atrial septal defect proved successful in all without any relevant residual shunts. In particular, complete closure was achieved in all patients after presumed paradoxical embolism. The mean period of follow-up is 9.5 months, with a range from 0.4 to 23.5 months, giving a total of 1898 patient months. The occlusion rate after three month was 98.1%. A trivial haemodynamically insignificant residual shunt remained in 1.9% of the patients. Fluoroscopy times ranged from 0 to 43.5 minutes, with a median of 8.7 minutes. The excellent results in the short and medium term in children and adults have resulted in using this device routinely at the present time for closure of central atrial septal defects up to a diameter of 28 mm. Final judgement, however, is only possible after long-term follow-up.

Adult↗
PubMed1999

Comparison of acute effects on right ventricular haemodynamics of surgical versus interventional closure of atrial septal defects.

OBJECTIVES: We compared the acute effects on right ventricular haemodynamics of surgical versus transcatheter closure of medium-sized atrial septal defects. METHODS: We studied 47 consecutive patients with a defect in the oval fossa and a ratio of pulmonary to systemic flows between 1.5: 1 and 2: 1. They were divided into two groups according to whether the defects were closed by surgery, performed in 23 patients, or by interventional catheterization, achieved in 24 patients. By means of transthoracic cross-sectional echocardiography, we measured right ventricular end-diastolic and endsystolic volumes and calculated ejection fractions. These calculations were performed before, and between 1 and 7 days after closure of the defect. RESULTS: Before closure of the defect, all patients had an enlarged right ventricle with normal function. After closure by either method, there was no difference in the rate of normalization of end-diastolic volume, but endsystolic volume remained enlarged. Thus, the calculated ejection fraction was lower than before closure. CONCLUSIONS: There was no difference in right ventricular volumes or function early after closure of atrial septal defects, irrespective of whether this was achieved surgically or via transcatheter closure.

Adolescent↗