Minimally invasive mitral valve surgery (MIMVS) does not refer to a single approach, but rather to a collection of new techniques and operation-specific technologies. These include enhanced visualization and instrumentation systems as well as modified perfusion methods, all directed toward minimizing surgical trauma by reducing the incision size. Cohn and Cosgrove, along with several European surgeons, first modified cardiopulmonary bypass techniques and reduced incision sizes to enable safe, effective, minimally invasive aortic and mitral valve surgery.1–3 Concurrently, port-access methods using endoaortic balloon occluders were developed.4 Despite expanding enthusiasm for minimally invasive valve surgery, many surgeons remained skeptical and became critical of complex operations done through small incisions, owing to possibilities of unsafe operations, unknown operative complexities, and inferior results.5,6
Despite circumspect reticence, significant advances were made and various institutions have published favorable results as single-center observational and comparative studies. Most surgeons who performed MIMVS in this era selected either a variation of a sternal incision or a minithoracotomy, and used direct vision with longer instruments. Simultaneous advances in cardiopulmonary perfusion, intracardiac visualization, instrumentation, and robotic telemanipulation hastened a technologic shift, with more surgeons adopting minimally invasive valve surgery in their practice. Less surgical trauma, blood loss, transfusions, and pain, translating into shorter hospital stays, faster return to normal activities, less use of rehabilitation resources, and overall healthcare savings, has driven further development in this field. Today, replacing and repairing cardiac valves through small incisions have become standard practices for many surgeons as patients become more aware of its increasing availability. Changes in surgical indications, largely because of a better understanding of the natural history of organic mitral regurgitation and improved repair techniques, have increased the number of less symptomatic patients with degenerative disease being referred for an elective repair.7,8 For MIMVS to become widely accepted, equivalent, if not better, short- and long-term outcomes have to be demonstrated compared with sternotomy operations.
To perform the ideal cardiac valve operation (Table 44-1) surgeons need to operate in restricted spaces through tiny incisions, which necessitate assisted vision and advanced instrumentation. Although the ultimate goal of a completely endoscopic mitral valve repair has not been widely achieved, MIMVS has continued to evolve, with many surgeons performing procedures along the minimally invasive continuum, utilizing a variety of techniques including either limited incisions, video-assistance, video-directed operations, or robotic techniques. Heretofore, completely endoscopic mitral valve repair was difficult but telemanipulators now offer ideal endoscopic techniques to mitral valve surgeons and their patients. However, the steep learning curve still can be an impediment to more widespread adoption. Video-assisted and direct vision techniques have placed MIMVS within the reach of most cardiac surgeons.
Table 44-1 The Ideal Cardiac Valve Operation |Favorite Table|Download (.pdf)
Table 44-1 The Ideal Cardiac Valve Operation
Single small endoscopic port
Central antegrade perfusion
Facile, secure valve attachment
Wide Intracardiac access