1/104. A new low profile balloon atrial septostomy catheter: initial animal and clinical experience.OBJECTIVE: To evaluate the safety and efficacy of a new low profile balloon septostomy catheter in neonatal animals as well as in one newborn infant. BACKGROUND: Balloon atrial septostomy remains one of the most commonly performed palliative procedures in pediatric cardiology. The currently available septostomy catheter requires a large introducer sheath (6 or 7F), does not have an end hole for confirmation of position or pressure measurement and is limited in patients with a small left atrium due to its large balloon inflated diameter. methods: Four neonatal piglets (average weight 3.9 kg) underwent percutaneous balloon atrial septostomy using the new balloon catheter inflated to 1 cc via a 5F sheath in the femoral vein. Two other piglets (average weight 4.9 kg) underwent septostomy with the conventional catheter inflated to 3.5 cc via a 6 or 7F sheath in the femoral vein. All animals underwent transthoracic echocardiography pre and post septostomy. All animals were sacrificed after the procedure and the size of the atrial defect created was measured. One neonate with Taussig-Bing anomaly underwent septostomy with the new balloon catheter. RESULTS: The left atrium was entered in all piglets. It was easier to enter the left atrium with an end hole catheter which was exchanged over a wire with the septostomy catheter. Septostomy was performed with the new or conventional catheters without complications. echocardiography demonstrated a very small patent foramen ovale prior to the procedure and a large atrial defect after septostomy. The average size of the defect created by the new catheter was 11.3 x 10 mm in diameter and 11 x 10 mm using the conventional catheter. A 10 x 10 mm atrial communication was created in the neonate. CONCLUSIONS: This study demonstrates the safety and efficacy of this new catheter. This catheter will be of potential importance in patients with a small left atrium and in small neonates with congenital heart disease requiring septostomy.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
2/104. Use of the laryngeal mask airway during repair of atrial septal defect in children.We describe the elective use of the laryngeal mask airway in two children undergoing cardiopulmonary bypass for repair of an atrial septal defect. Total surgical time was short and cardiopulmonary bypass performed at normothermia allowing removal of the laryngeal mask airway on the operating table on completion of surgery. We were able to adequately oxygenate and ventilate the children throughout the procedure using positive pressure ventilation and spontaneous ventilation. The use of caudal fentanyl and rectal diclofenac aided postoperative pain management. Atrial septal defect repair has become one of the more straightforward cardiac operations partly as a result of new cardiopulmonary bypass techniques. Avoidance of intubation and postoperative ventilation in appropriate patients would make this procedure ideal for 'fast tracking' and offers the potential advantages of decreased length of stay in hospital and reduction in overall costs.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
3/104. Right-to-left interatrial shunt in ARDS: dramatic improvement in prone position.The mechanisms leading to shunting through a patent foramen ovale include high right-sided cardiac pressures and respiratory factors due to mechanical ventilation and also anatomical changes in the right atrium as described in the platypnea-orthodeoxia syndrome. We report a patient with the adult respiratory distress syndrome (ARDS) who had a right-to-left atrial shunt which decreased in the prone position, after which oxygenation improved. The patient was admitted to the intensive care unit because of ARDS due to an invasive fungal infection. He had a history of chronic lymphocytic leukemia and paradoxical embolisms through a patent foramen ovale. Despite mechanical ventilation and antifungal treatment he developed severe ARDS. He was therefore turned to the prone position. blood gas values improved dramatically (arterial oxygen tension/fractional inspired oxygen ratio increasing from 59 to 278 torr). Transcranial Doppler sonography was performed with bubble study, which confirmed a massive right-to-left shunt in the supine position and which instantaneously decreased in the prone position. This case suggests that a decrease in right-to-left shunt in patients who have a patent foramen ovale could partly explain the improvement in hypoxemia in the prone position.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
4/104. A case of diffuse pulmonary arteriovenous fistula.A 30-year-old Japanese woman was admitted to hospital for dyspnea. She had a history of corrective surgery for a large atrial septal defect and partial anomalous pulmonary venous drainage, which had produced cyanosis in her infancy. However, her cyanosis continued postoperatively. angiography revealed a double inferior vena cava (IVC), with the left IVC connected with the hemiazygos vein and the right IVC with the left atrium through a very small orifice. Most of the blood from the 2 IVCs flowed into the superior vena cava via the distended azygos and hemiazygos veins. Pulmonary arteriography revealed no abnormal structures. Pulmonary arterial pressure was normal. There was marked pulmonary venous oxygen desaturation. perfusion lung scintigraphy revealed multiple segmental perfusion defects. These findings suggested the presence of diffuse microscopic pulmonary arteriovenous fistulas bilaterally in the lungs. The patient appears to be the first reported adult case of microscopic and diffuse arteriovenous fistulas. Neither resection of the arteriovenous fistulas nor corrective surgery for the diversion was indicated, and heart-lung transplantation might be the only treatment able to relieve her dyspnea.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
5/104. Patent foramen ovale and implantable cardioverter defibrillator.A case of patent foramen ovale opening was observed concomitantly to a defibrillation threshold determination in the setting of an internal cardioverter defibrillator implantation. The subsequent transient right-to-left shunt was confirmed by a peroperative transoesophageal echocontrast study. The underlying mechanism of this incident may be related to a transient reversal of the interatrial gradient, due to the pre-existence of pulmonary hypertension and tricuspid regurgitation, associated with ongoing mechanical ventilation and modifications of intracardiac pressures regimen secondary to the succeeding ventricular tachyarrhythmia and defibrillation. Paradoxical embolism can be an aetiology for neurologic injury during internal cardioverter defibrillator implantation.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
6/104. Intermittent hypoxaemia without orthodeoxia due to right-to-left shunting related to an elongated aorta.An elderly woman presented with unexplained, intermittent hypoxaemia unrelated to posture. Subsequent investigations revealed intermittent and variable right-to-left interatrial shunting through a patent foramen ovale in the presence of normal pulmonary arterial and intracardiac pressures, caused by right atrial compression from a horizontal, elongated ascending aorta. Surgical closure of the foramen resulted in marked clinical improvement.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
7/104. Contrast echocardiography and transcranial Doppler sonography for detection of a patent foramen ovale.We report the case of a patient, in whom a patent foramen ovale was detected. For the detection of a patent foramen ovale simulation of Valsalva's manoeuvre with a positive airway pressure of 20 cm H2O was applied. Change of ventilation manoeuvre by ventilation with positive airway pressure of 35/30/15 cm H2O at a tidal volume of 1200 ml make a distinct increase in passage of contrast medium from the right to the left atrium. These findings were detected by contrast transesophageal echocardiography and indirectly by transcranial Doppler sonography and were reproducible. This may stress the importance of preoperative screening of patent foramen ovale in patients to be operated on in the sitting position. Contrast echocardiography and the ventilatory manoeuvre with high airway pressure and PEEP might increase the detection rate of patent foramen ovale with a right to left shunt during general anaesthesia.- - - - - - - - - - ranking = 3keywords = pressure (Clic here for more details about this article) |
8/104. Platypnoea-orthodeoxia syndrome.PLATYPNOEA: orthodeoxia is a rare syndrome of postural hypoxaemia accompanied by breathlessness. The predominant symptom, dyspnoea induced by upright posture, can be debilitating and difficult to discern without thorough evaluation of the patient's pattern of dyspnoea. The precise cause of the syndrome is unclear but patients develop right to left intracardiac shunting in the presence of normal right sided cardiac pressures. Initially, patients should have confirmation of orthostatic desaturation by erect and supine pulse oximetry. However, definitive diagnosis of an orthostatic intracardiac shunt is most readily established by echocardiography. The use of echocontrast with postural manoeuvres may facilitate the diagnosis. The treatment of choice is surgical closure of the intracardiac (usually interatrial) communication, which may result in dramatic symptomatic and haemodynamic improvement. Three cases (a 27 year old man and two women aged 63 and 72 years) are described that exemplify the presentation of this syndrome, and reflect the varied management strategies and outcomes of this condition.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
9/104. Intermittent atrial level right-to-left shunt with temporary hypoxemia in a patient during support with a left ventricular assist device.We report a 56-year-old male patient developing hypoxemia after surgical replacement of infected valves of a left ventricular assist device (LVAD, Novacor) which had supported him during the previous 15 months. Contrast transesophageal echocardiography (TEE) revealed an atrial septal defect with intermittent right-to-left shunt across a patent foramen ovale. We postulate that the shunt detected in this patient occurred as a consequence of reduced pulmonary vascular compliance due to positive end-expiratory pressure (PEEP) and an increase of mean intrathoracic pressure. Furthermore, we hypothesize that synchronized LVAD operation exacerbates any potential right-to-left shunt due to the profound left ventricular unloading which occurs during LVAD support. In this first report of a right-to-left shunt from a previously unrecognized patent foramen ovale in a Novacor patient, the subsequent transient hypoxemia could be managed by avoiding PEEP of more than 3 mmHg, and mean airway pressure of more than 11 mmHg and by careful volume replacement in order to prevent the pump from completely emptying the left ventricle (LV) and the left atrium (LA). Thus, prior to every LVAD implantation a transesophageal contrast echocardiography with valsalva maneuver should be performed to identify intracardiac right-to-left shunt.- - - - - - - - - - ranking = 3keywords = pressure (Clic here for more details about this article) |
10/104. Combined percutaneous atrial septal defect occlusion and pulmonary balloon valvuloplasty in adult patients.Severe pulmonary stenosis in association with a large atrial septal defect is uncommon. When these 2 conditions are present, significant left-to-right shunt is often prevented by the outflow obstruction, which protects the pulmonary bed until adulthood. This report shows our initial experience of percutaneous treatment of both congenital malformations, either staged or combined in the same procedure, in 2 adult patients whose treatments yielded effective atrial septal defect occlusion and right ventricular pressure relief that persisted at mid-term follow-up. Although these opposite procedures (opening and closing) have been applied as isolated methods of treatment, this preliminary experience appears to demonstrate the feasibility and effectiveness of a combined percutaneous treatment.- - - - - - - - - - ranking = 1keywords = pressure (Clic here for more details about this article) |
| | Next -> |