Original Articles: Cardiovascular Minimally Invasive Cardiac Surgical Techniques in the Closure of Ventricular Septal Defect: An Alternative Approach
Division of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital, Chang Gung Medical College, Taipei, Taiwan
Department of Pediatrics, Chang Gung Memorial Hospital, Chang Gung Medical College, Taipei, Taiwan
Department of Anesthesiology, Chang Gung Memorial Hospital, Chang Gung Medical College, Taipei, Taiwan
Accepted for publication July 5, 1997.
Dr Lin, Division of Thoracic and Cardiovascular Surgery, Children’s Hospital, Chang Gung Memorial Hospital, Chang Gung Medical College, 199, Tun-Hwa North Rd, Taipei, Taiwan.
Background.Minimally invasive cardiac surgical techniques recently have been applied in the management of a variety of intracardiac lesions. Methods. Fourteen patients (6 boys and 8 girls; age, 8.9 ± 5.5 years; body weight, 29.0 ± 13.5 kg) were operated on using minimally invasive cardiac surgical techniques for the closure of a ventricular septal defect (subarterial in 11 patients and perimembranous in 3 patients).
The operations were performed through a left anterior minithoracotomy and were guided by video-assisted endoscopic techniques under femorofemoral cardiopulmonary bypass. The myocardium was protected by continuous coronary perfusion with hypothermic fibrillatory arrest. The right ventricular outflow tract was entered after pericardiotomy was performed.
Results. Closure of the defect (directly in 4 patients and by patch in 10 patients) was performed successfully in all patients. A right ventricular outflow tract obstruction and ruptured sinus of Valsalva aneurysm also were repaired in 1 patient each. The duration of cardiopulmonary bypass was 41 ± 10 minutes (range, 28 to 100 minutes) and the total operative time was 2.2 ± 0.8 hours (range, 1.3 to 3.5 hours).
All the patients recovered rapidly from their operation and had an uneventful postoperative course. Follow-up (mean, 6.2 months; range, 6 to 9 months) was complete in all patients. There were no late deaths. Transthoracic echocardiographic examination showed no residual shunt and no aortic regurgitation in all patients.
Conclusions. Our experience demonstrates that minimally invasive cardiac surgical techniques are technically feasible and an alternative option for the repair of a ventricular septal defect.
Video-assisted endoscopic techniques have been used in many surgical subspecialties to reduce incisional pain and shorten the hospital stay. Advances in video instrumentation have made minimally invasive thoracic operations possible . These operations have been used in the treatment of coronary artery disease and the repair of congenital cardiac lesions when the use of cardiopulmonary bypass was not required .
Recently, minimally invasive cardiac surgical techniques have been used to repair intracardiac lesions, congenital or acquired, through a right or left anterior minithoracotomy . Our experience showed that closure of an atrial septal defect could be performed safely with the use of video-assisted endoscopic techniques under femorofemoral or femoral-right atrial cardiopulmonary bypass.
Median sternotomy is the standard approach for surgical intervention in ventricular septal defect (VSD). However, the use of minimally invasive cardiac surgical techniques might be an alternative approach in the surgical treatment of VSD. We report our experience with the use of minimally invasive cardiac surgical techniques in the closure of VSD in 14 pediatric patients.
Material and Methods
Fourteen selected patients were operated on for VSD and associated cardiac lesions from March to September 1996. There were 6 boys and 8 girls with a mean age of 6.3 ± 5.0 years (range, 1.5 to 18.9 years). Their mean body weight was 29.0 ± 13.5 kg (range, 13.1 to 59.0 kg). Transthoracic echocardiography and cardiac catheterization confirmed the diagnosis of VSD. The location of the VSD was subarterial in 11 patients and perimembranous in 3 patients.
Prolapse of the aortic cusp was noted in 10 patients, with mild aortic regurgitation in 7 patients. The pulmonary-to-systemic flow ratio was 1.9 ± 0.3 (range, 1.5 to 2.6). The mean pulmonary artery pressure was 20 ± 3 mm Hg (range, 16 to 24 mm Hg). Infundibular stenosis was observed in 1 patient, with a pressure gradient across the right ventricular outflow tract of 57 mm Hg. A right sinus of Valsalva aneurysm ruptured into the right ventricle also was seen in 1 patient.
The operative policy to use minimally invasive cardiac surgical techniques for the closure of VSD was approved by the appropriate hospital authorities. Written consent was obtained from the family members before operation.
After the induction of general anesthesia, transesophageal echocardiographic monitoring was set up and the diagnosis of VSD was confirmed. The patient was placed in a supine position with the left groin exposed. Cardiopulmonary bypass was established through cannulation of the left femoral artery with an aortic cannula (THI aortic perfusion cannula; Argyle, Division of Sherwood Medical, St. Louis, MO) and the left femoral vein with a chest tube (10F to 28F thoracic catheter; Mallinckrodt Laboratories, Athlone, Ireland), up to the level of the diaphragm.
A membranous oxygenator (Maxima Plus oxygenation system; Medtronic, Inc, Cardiopulmonary Division, Anaheim, CA) was used. Systemic hypothermia was begun immediately after the initiation of cardiopulmonary bypass.
A left anterior parasternal minithoracotomy (4- to 6-cm; Fig 1) was performed and the pleural space was entered through the third or fourth intercostal space in patients with a subarterial or perimembranous VSD. The third or fourth costal cartilage sometimes was divided, without resection, to increase exposure. The left internal thoracic artery was well preserved.
A 10-mm endoscope (Stryker Endoscopy, San Jose, CA) and other conventional surgical instruments were introduced through the thoracotomy. Because the length of both the thoracotomy and the ventriculotomy was short, illumination during repair of the VSD usually was not good. The video-assisted endoscope was used to provide illumination and guide the repair procedure.