Abstract

Endoscopic bypass grafting can be complicated by limited intraoperative orientation. A method to overlay the preoperative model of the coronary tree on the live endoscopic images of the heart was therefore developed. The method is three-fold: (1) the three-dimensional (3D) model of the coronary tree is reconstructed from traditional angiograms; (2) preoperative images are registered with the intraoperative position of the patient in the operating room (OR); and (3) an iterative and interactive identification of clinically relevant landmarks within the operative field on the heart surface before their registration with the preoperative model of the coronaries. This algorithm allows one to compensate deformations (breathing, intraoperative heart shift) and leads to a precise overlay of the coronary network on the heart surface. For ergonomic reasons, the 3D model can be displayed directly within the visual field of any telesurgical master console. It thus provides an effective navigational aid to the surgeon similar to a global positioning system (GPS) in vehicles. Animal trials have been performed using the Da Vinci (Intuitive Surgical, Sunnyvale, CA, USA) teleoperated system to validate the method. Qualitative and quantitative analysis demonstrate the potential value during total endoscopic coronary artery bypass grafting.

Abstract

Stentless mitral valve (SMV) replacement is an intriguing concept to preserve the functionality of the physiological mitral valve (MV). Beginning in August 1997 to date, 51 patients, 35 females and 16 males (age: 68.3+/-8.4 years), with severe MV disease (stenosis 25, incompetence 17, mixed lesion 9) received a chordally supported SMV. SMV implantation was performed using a conventional sternotomy in 32, or a minimally invasive lateral minithoracotomy approach in 19 of the patients. Mean valve size was 29+/-1.5 mm; cross-clamp duration was 81+/-33 min. The perioperative mortality rate was comparable to conventional MV repair or replacement. Regular echocardiographic control disclosed good SMV function (Vmax 1.7+/-0.2 m/s, Pmean 3.9+/-1.2 mmHg) and well-preserved ejection fraction postoperatively, as well as at their most recent follow-up visit. SMV implantation by way of a sternotomy or lateral minithoracotomy leads to preservation of the annulo-ventricular continuity and similar to physiological hemodynamics. However, long-term durability remains to be proven.

Abstract

This clinical feasibility study was planned to evaluate pericardioscopy as a means of control of the pericardial cavity during drainage for pericardial effusion by a surgical sub xyphoid approach. Seventeen patients who underwent an operation for surgical drainage of the pericardium (11 medical and 6 postoperative pericardial effusions) benefited from a pericardial exploration with a mediastinoscope or rigid thoracoscope (Karl Storz, Germany). In 7 of the 11 medical cases, a severe inflammation of the pericardium associated with false membranes was visualized; in 3 cases, the pericardium was considered as normal; and in 1 case, pericardial metastases were visualized. In the 6 postoperative cases, clots were visualized with a venous bypass graft and the pulmonary cannula of a right ventricular assist device (Thoratec, USA) was also perfectly controlled. The cause of bleeding was reported in one case and suspected in another, but required total sternotomy for repair in both cases. No mortality or morbidity was reported to be directly due to the technique. The peroperative assessment of pericardial cavity is possible by use of pericardioscopy with a satisfactory resolution, but visualization of the left lateral part of the heart remains difficult. The possibility exists to partially remove clots and false membranes, obtain various samples, and control the position of the drains. Improvement in the optic device with the possibility of a flexible device that has a tip protector for optimal visualization, may improve both the technique and results.

Abstract

Aortic aneurysms continue to be a major source of morbidity and mortality despite advances in operative and perioperative technology. Endovascular stent graft repair of abdominal aortic aneurysms has been widely adopted since its initial report in 1991. Improvements in device delivery systems and development of modular bifurcated stent grafts have greatly facilitated repair, and broadened the applicability of these techniques. However, aneurysmal involvement of critical branch vessels can be problematic. Experience is growing with custom-made branched endografts to maintain antegrade perfusion to critical arteries in treatment of thoracoabdominal and complex aortoiliac aneurysms. The use of branched devices allows for extension of the sealing and fixation portions of the graft into more stable aorta, while simultaneously maintaining branch vessel patency. Much remains to be learned regarding the long-term durability of these repairs; however, as additional devices are developed, it is evident that the limitations of endovascular aortic aneurysm repair will continue to diminish.

Abstract

In addition to conventional and endovascular techniques, laparoscopic surgery is becoming a third way to treat patients with aortoiliac occlusive or aneurysmal diseases. Several different laparoscopic techniques are available, but most authors are stressing the need for development of specific laparoscopic aortic instruments, to decrease the operative and clamping times and reduce the learning curve. Our experience of more than 150 patients who underwent a laparoscopic abdominal or thoracic aortic reconstruction, has lead us to imagine the instruments that may facilitate these procedures, and then to create a society with Vascular Surgeons and Biomedical Engineers, called PROTOMED, which may conceive, develop, and test new medical instruments. This Chapter presents an overview of what is available currently, such as laparoscopic aortic clamps or laparoscopic intestinal retractors; others are in the experimental stage, such as laparoscopic aortic staplers, anastomotic devices, and robotic surgical systems. This important technologic challenge should lead to 2 major orientations: development of qualitative in vitro and in vivo experiments to test these new products, and training courses to teach their use. Minimally aggressive techniques are well adapted to a western population growing older and has access to constantly improving medical care; however, only specific and ergonomic instruments will allow these new techniques to be widely embraced by the vascular surgical community.