Rapid progress and constant innovation are being made in the field of less invasive approaches for intervention in valvular heart disease, both in the fields of minimally invasive surgery and catheter-interventional techniques. In this session an overview of the recent advances was given with both cardiological and surgical perspectives.
In the first talk, Professor F Mohr from Leipzig, Germany elucidated the options in minimally invasive mitral valve repair. Four levels of minimally invasive procedures have to be differentiated: level 1 being defined as a limited incision, levels 2 and 3 consisting of video assisted and video directed surgery respectively, and finally level 4 defined as robotic surgery. While all of these levels are principally possible for mitral valve surgery, the speaker stressed that in his own experience he most frequently used level 3. The main aims of mitral valve surgery are the preservation and restoration of the natural structures, achieving an optimal ?? coaptation, preservation of the mitral valve, left ventricular function and annulo-ventricular continuity, as well as ?? obtention of durable results. These aims will be achieved with a successful mitral valve repair. However, while selected centres have success rates of up to 90% or more and although progress has been made, on a general basis only about 50% of patients undergo valve repair, while the rest of the patients receive a prosthetic valve. Different repair techniques are currently used in a minimally invasive approach with a low incidence of residual regurgitation and low mortality rates that are comparable to conventional techniques.
In the second talk Professor A Vahanian from Paris, France discussed the percutaneous approaches to mitral regurgitation. At the beginning of his presentation he stressed that surgery is now an accepted treatment strategy for most of these patients with low mortality rates. However, he added that surgical risk is increasing when the valve needs to be replaced and even more so when additional coronary artery bypass grafting needs to be performed. He stressed that according to data from the Euroheart Survey on valvular heart disease, about half of the patients with symptomatic mitral regurgitation were not referred to surgery and that percutaneous techniques might offer a niche indication for some of these patients. Currently the most advanced technique is the “edge to edge repair” which can be performed from a transseptal approach similar to the concept of an Alfieri stitch, where a clip or a suture is used to join the two mitral valve leaflets in the middle, thus producing a double orifice valve. The Everest trial showed that mitral valve clipping was feasible in about 85% of patients with an event free survival rate of 80% after two years. However, some of these patients have residual regurgitation of a moderate degree. The ongoing Everest II study, which randomly compared this technique to surgery, will bring more definite answers. Another technique that is being developed is annuloplasty, where a device is introduced into the coronary sinus, which can then be tightened. However, the distance from the coronary sinus to the mitral valve level might be up to 2.6 cm and there is a theoretical risk of impairment of the circumflex artery.
Professor A P Kappetein from Rotterdam discussed the role of minimally invasive approaches to aortic valve repair. He stressed that less invasive strategies for aortic valve repair are more or less limited to smaller incisions such as partial sternotomies or a parasternal mini-thoracotomy. The technique is contraindicated in the presence of coronary artery disease, of a very short or long aorta or extensive calcification of the aorta. The advantages comprise faster healing, less blood loss and smaller scars at the price of technical difficulties and an increased duration of surgery.
In the last presentation Professor A Cribier from Rouen, France presented the latest information on percutaneous aortic valve replacement, the concept being “to offer a unique therapeutic option to patients with degenerative aortic stenosis at high risk for aortic valve replacement”. The technique consists of the implantation of the Cribier valve bioprosthesis, which is mounted on a balloon-expandable stent that is positioned at the aortic valve level via a retrograde or antegrade approach. The technique has been shown to be feasible in humans. Recent advances in the technique include the development of the FLEX-catheter, which allows steering through arterial and aortic tortuosities for a retrograde approach. Furthermore, a second larger valve size of 26mm (versus 23mm) has been introduced to reduce the incidence of paravalvular leaks. When vascular access cannot be warranted, a new concept consisting of a transapical implantation of the valve has been presented.