Heart valve disease is a widespread condition in which one or more of the valves of the heart fails to function properly. Various surgical techniques may be used to repair a diseased or damaged valve, including securing a cardiac implant to the diseased annulus. Cardiac implants include a prosthetic heart valves and annuloplasty rings. In a valve replacement operation, the damaged leaflets are excised and the annulus sculpted to receive a replacement valve. About one-half of patients receive a mechanical heart valve, which are composed of rigid, synthetic materials, and the remaining patients received bioprosthetic heart valve replacements, which utilize biologically derived tissues for flexible fluid occluding leaflets. Another less drastic method for treating defective valves is through repair or reconstruction, which is typically used on minimally calcified valves. One repair technique that has been shown to be effective in treating incompetence is annuloplasty, in which the deformed valve annulus is reshaped by attaching a prosthetic annuloplasty repair segment or ring to the valve annulus.
In a typical cardiac implant procedure, the aorta is incised and, in a valve replacement operation, the defective valve is removed leaving the desired placement site that may include a fibrous tissue layer or annular tissue. Known cardiac implant techniques include individually pre-installing sutures through the fibrous tissue or desired placement site within the valve annulus to form an array of sutures. Free ends of the sutures are draped out of the thoracic cavity and are spaced apart, sometimes being distributed around a suture organizer. The free ends of the sutures are then individually threaded through a suture-permeable sewing edge of the annuloplasty ring or prosthetic heart valve. Once all sutures have been run through the sewing edge (typically 12 to 18 sutures), all the sutures are pulled up taught and the prosthesis is slid or “parachuted” down until it sits against the target annulus. The cardiac implant is then secured in place by traditional knot tying of the anchoring sutures on the proximal side of the sewing edge. There are often 7-10 knots on each suture advanced by pushing the knot one at a time to the desired location by using a knot pusher device. This procedure is obviously time-consuming.
During open-heart procedures, the patient is on heart-lung bypass which reduces the patient's oxygen level and creates non-physiologic blood flow dynamics. The longer a patient is on heart-lung bypass, the greater the risk for complications including permanent health damage. Existing techniques for suturing cardiac implants extend the duration of bypass and increase the health risks due to heart-lung bypass. Furthermore, the securing force created by suturing varies significantly because the pre-tensioning of the suture just prior to knot tying is difficult to consistently maintain, even for an experienced medical professional.
There exists a need for devices and methods that reduce the time required to secure a medical implant in place. Additionally, there exists a need to make it easier to secure a cardiac implant, in particular, in place. Currently, a clinician must work in the limited space near the heart to tie knots in sutures. This is a cumbersome process even for a clinician of great dexterity and patience.