Biomedical subjects

Bassem N Mora

Publications and source records attributed to Bassem N Mora.

6 recordsLinked to original sources

PubMed2006

The presentation and management of vascular rings: an otolaryngology perspective.

OBJECTIVE: To review the presentation and natural history of children with vascular rings and present management guidelines. METHODS: Retrospective study of tertiary care pediatric medical center charts from 1991 to 2002. RESULTS: There were 37 males and 27 females with a diagnosis of vascular rings. At presentation, 91% of patients had airway symptoms and 47% had esophageal symptoms. Airway symptoms included stridor (63%), recurrent respiratory infections (47%), respiratory distress (19%), and cough (17%). The most common esophageal symptom was dysphagia (27%). Pre-operative studies included: echocardiography (96%), chest X-ray (93%), barium swallow (75%), magnetic resonance imaging (MRI) (60%), and computerized tomography (CT) scan of the chest (59%). Surgical management included open (n=25) and thoracoscopic (n=39) approach. Complications included recurrent laryngeal nerve injury in five patients (8%). CONCLUSION: Children with vascular rings present with respiratory and/or feeding difficulty. The evaluation should include chest X-ray, echocardiography, and barium swallow. Direct laryngoscopy and bronchoscopy are recommended to assess the degree of compression of the airway and/or esophagus, tracheomalacia, and vocal fold motion prior to intervention. Indication for surgical release is given when the diagnosis is made and can be assisted by advanced radiology studies. Surgical options include minimally invasive techniques involving either thoracoscopic or robotic-assisted repairs, as well as open procedures involving thoracotomy.

Aorta, Thoracic↗

PubMed2005

Single-ventricle palliation for high-risk neonates: the emergence of an alternative hybrid stage I strategy.

BACKGROUND: Survival after stage I palliation for hypoplastic left heart syndrome or related anomalies remains poor in high-risk neonates. We hypothesized that a less invasive hybrid approach would be beneficial in this patient population. METHODS: The hybrid stage I procedure was performed in the catheterization laboratory. Via a median sternotomy, both branch pulmonary arteries were banded, and a ductal stent was delivered via a main pulmonary artery puncture and positioned under fluoroscopic guidance. RESULTS: Between October 2003 and June 2005, 14 high-risk neonates underwent a hybrid stage I procedure. Eleven of 14 had hypoplastic left heart syndrome. Two also underwent peratrial atrial septal stenting, and 5 required percutaneous atrial stenting later. Two neonates with an intact or highly restrictive atrial septum had emergency percutaneous atrial stent placement. Hospital survival was 11 (78.5%) of 14. One patient required extracorporeal membrane oxygenation support for intraoperative cardiac arrest. He underwent cardiac transplantation but died later of sepsis. One patient died of ductal stent embolization, and a third died of progressive cardiac dysfunction. The first 4 patients required pulmonary artery band revisions. There were none after we modified our technique and added branch pulmonary artery angiograms. There were 2 interstage deaths from atrial stent occlusion and from preductal retrograde coarctation. Eight patients underwent stage II procedures, consisting of aortic arch reconstruction, atrial septectomy, and cavopulmonary shunt. Two patients died after stage II. One patient is awaiting stage II. CONCLUSIONS: The hybrid stage I palliation is a valid option in high-risk neonates. As experience is accrued, it may become the preferred alternative. However, in aortic atresia, the development of preductal retrograde coarctation is a significant problem.

Cardiac Surgical Procedures↗

PubMed2005

Totally endoscopic robotic-assisted repair of patent ductus arteriosus and vascular ring in children.

BACKGROUND: This study reports on our initial experience with robotically assisted patent ductus arteriosus (PDA) closure and vascular ring division in children. METHODS: From April 2002 to May 2004, 15 patients underwent PDA closure (n = 9) and vascular ring repair (n = 6) by a totally endoscopic approach, utilizing the Da Vinci robotic system. The mean age of the patients was 8.3 +/- 4.7 years (range, 3 to 18) and the mean weight, 35.5 +/- 19.0 kg (range, 14.1 to 77.0 kg). Three thoracoscopic trocars were used to accommodate the endoscopic camera and two surgical instruments with an additional small incision for lung retraction. After dissection by the surgeon seated at the master console, PDA ligation with clips or division of the atretic arch and ductal ligament was performed. RESULTS: Total operative times were 170 +/- 46 minutes (PDA) and 167 +/- 48 minutes (vascular ring). One patient with vascular ring was converted to thoracotomy because of dense adhesions due to previous surgery. Precise and easy surgical maneuver was possible with the articulated surgical instruments and three-dimensional visualization in 14 patients. Intraoperative transesophageal echocardiography confirmed no persistent shunt in all PDA patients. No laryngeal nerve injury and hemorrhage were noted. All patients were extubated in the operating room. Median length of postoperative hospital stay was 1.5 days. CONCLUSIONS: Robotically assisted PDA closure and vascular ring division is a feasible and safe procedure. Future technologic improvement, including smaller instrument size and incorporation of tactile feedback, may permit application of this technique to even younger infants and intracardiac repairs.

Adolescent↗

PubMed2004

Three-dimensional echocardiography-guided atrial septectomy: an experimental study.

OBJECTIVES: The surgical feasibility of beating-heart atrial septectomy under the guidance of two different types of real-time 3-dimensional echocardiography systems was examined. METHODS: A modified real-time 3-dimensional echocardiography system with a x4 matrix transducer (Sonos 7500; Philips Medical Systems, Andover, Mass) or a mechanical 1-dimensional array transducer (SSD-5500; Aloka Co, Ltd, Tokyo, Japan) was used. Small porcine atrial septal defects (n = 8) were enlarged with a Kerrison bone punch in the tank model. In the animal studies, small atrial septal defects (n = 8) were enlarged with the same device through a transatrial port. In both experiments, the area of the atrial septal defect measured by real-time 3-dimensional echocardiography was compared with the area measured directly. RESULTS: Real-time 3-dimensional echocardiography provided satisfactory images and sufficient anatomic detail for the atrial septectomy in both experimental settings. All the atrial septal defects were successfully enlarged; an increase of as much as 293% of the preoperative atrial septal defect area was achieved in the tank experiment, and an increase of as great as 449% of the preoperative area was achieved in the animal experiment. The size of the atrial shunt was increased significantly after the atrial septectomy relative to that before the surgery (P <.0001). The percentage enlargement of the atrial septal defect measured by real-time 3-dimensional echocardiography was strongly correlated with that measured directly (both r(2) = 0.997, P <.0001) Bland-Altman analysis showed close agreement between the results obtained by the two measurement methods in both models. CONCLUSIONS: Real-time 3-dimensional echocardiography provides satisfactory images and sufficient anatomic detail for atrial septectomy. This experiment demonstrates the surgical feasibility of a beating-heart intracardiac procedure such as atrial septectomy under real-time 3-dimensional echocardiographic guidance.

Animals↗

PubMed2004

Three-dimensional echocardiography-guided beating-heart surgery without cardiopulmonary bypass: a feasibility study.

BACKGROUND: There is no current acceptable approach for intracardiac beating-heart interventions. We have adapted real-time 3-dimensional echocardiography with specialized instrumentation to facilitate beating-heart repair of atrial septal defects and mitral valve plasty to investigate the feasibility of real-time 3-dimensional echocardiography-guided cardiac surgery. METHODS: In experiment I a modified real-time 3-dimensional echocardiography system with x4 matrix transducer was compared with 2-dimensional echocardiography in the performance of common surgical tasks. Completion times, deviation from an ideal trajectory, and an echogenic target were measured. In experiment II porcine atrial septal defects were closed with an original semiautomatic suturing device (n = 4) and with a 5-mm endoscopic stapler and a pericardial or polytetrafluoroethylene patch (n = 4). In experiment III a pulsatile porcine mitral valve model was developed, and suture placement through the anterior and posterior mitral leaflets was performed (n = 8). During all experiments, the operator was blinded to the target and operated on only with ultrasonic guidance. RESULTS: In experiment I, compared with 2-dimensional echocardiographic guidance, completion times improved by 21% ( P <.01) with high-trajectory accuracy, and suture deviation was significantly smaller (2-dimensional echocardiography, 5.4 +/- 2.7 mm; 3-dimensional echocardiography, 1.7 +/- 0.7 mm; P <.05) in real-time 3-dimensional echocardiography-guided tasks. In experiments II and III in both atrial septal defect closure and mitral valve plasty, real-time 3-dimensional echocardiography provided satisfactory images and sufficient anatomic detail for suturing and patch deployment. All surgical tasks were successfully performed with accuracy. CONCLUSIONS: Real-time 3-dimensional echocardiography provides adequate imaging and anatomic detail to act as a sole guide for surgical task performance. These initial experiments demonstrate the feasibility of beating-heart direct or patch closure of atrial septal defects and mitral valve plasty without cardiopulmonary bypass.

Animals↗

PubMed2003

Composite aortic root replacement with a bovine pericardial valve conduit.

In order to offer selected patients undergoing composite aortic root replacement the advantages of a tissue valve, we have constructed conduits intraoperatively by suturing a stented bovine pericardial valve (Edwards Life-sciences LLC, Irvine, CA) inside of a Dacron tube graft (Boston Scientific Corp, Natick, MA). The conduit is quickly made from readily available materials, is easily implanted, and can accommodate any of the anatomic situations encountered in repair of aortic root aneurysms. It is particularly suitable for patients 65 years of age and older.

Aorta↗