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MMCTS
(May 23, 2008). doi:10.1510/mmcts.2007.002766 Copyright © 2008 European Association for Cardio-thoracic Surgery Procedure Tricuspid valve annuloplasty for functional regurgitationBluhm Cardiovascular Institute, Northwestern Memorial Hospital, Northwestern University's Feinberg School of Medicine, 201 East Huron St, Suite 11–140, Chicago, IL 60611, USA * Corresponding author: Surgical Director, Heart Transplantation and Mechanical Assistance. Tel.: +1-312-695-0454; fax: +1-312-695-1903emcgee{at}nmh.org
Functional tricuspid regurgitation (TR) is present in many patients with advanced heart failure. The following manuscript and videos describe our approach to its correction.
Key Words: Annuloplasty • Functional tricuspid regurgitation • Heart failure
As surgeons we are being asked to operate on an ever increasingly older patient population that often suffers from heart failure. Significant tricuspid regurgitation often exists in this population and contributes to right heart failure. In the majority of these patients, the valve leaflets are normal but leaflets coapt poorly secondary to annular dilatation (Carpentier classification type I) [1]. Several techniques, based on suture annuloplasty, such as the De Vega and Kay repairs, have been described for tricuspid valve repair [2, 3]. It is our preference to use formal ring annuloplasty given its superior durability [4, 5, 6]. The manuscript and videos that follow outline our current approach to tricuspid repair using the Edwards MC3 Annuloplasty system.
Anesthesia
After systemic heparinization, standard aortic cannulation is accomplished. Bicaval cannulation is carried out of the superior vena cava (SVC) and inferior vena cava (IVC) directly. For most individuals a 24 right angled cannula (Edwards VCCS02490 – MMCTSLink 117) is placed in the SVC and a 26 right angled cannula (Edwards VCS02690 – MMCTSLink 117) is used in the IVC. We usually perform tricuspid procedures as a concomitant procedure at the end of a complex operation. As long as there is no patent foramen ovale, we perform the tricuspid repair with the heart beating. Doing so allows the heart to reperfuse and facilitates prompt separation from bypass once the atrium is closed. If a patent foramen ovale is identified, it is repaired before declamping. For isolated tricuspid procedures it is our preference to repair a patent foramen ovale under a brief period of cardioplegic arrest. Alternatively, a brief period of ventricular fibrillation can be induced to prevent any air entrainment into the left atrium. After full deairing, tapes are secured about the IVC and SVC to achieve right heart isolation. Should adhesions be significant, SVC isolation can be achieved with a caval clamp. The right atrium is opened with an incision that parallels the atrioventricular (AV) groove down toward the IVC cannulae. For procedures that involve the tricuspid valve, we place our retrograde cardioplegia catheter so that its entry site is incorporated into the atriotomy (Video 1).
A self retaining retractor is typically used, although a hand held retractor may suffice. Occasionally, fine pledgeted traction sutures are placed at the edges of the atriotomy to enhance exposure. A flexible weighted vent is placed in the coronary sinus to scavenge blood. Attention is then directed toward the tricuspid valve. The valve is inspected and the pathology addressed. For pure annular dilation a down-sized annuloplasty is all that is required. 2-0 permanent braided sutures are placed about the annulus starting at the anterior leaflet and ending just medial to the coronary sinus and thus avoiding the bundle of His (Schematic 1). The pulmonary artery catheter may be left in place, or temporarily pulled back into the right atrium.
Care is taken to avoid passing any sutures through the leaflets. Medial traction on the leaflet displays the annulus. Sutures are placed 2 mm deep and 2 mm from the annulus. Saline irrigation from an assistant is also helpful. Care must be taken against overzealous placement of the first few sutures as the aortic root is in close proximity to the tricuspid annulus in this area. The conduction system is preserved by typically not placing any sutures in the annulus adjacent to the septal leaflet past the medial aspect of the coronary sinus (Video 2). The triangle of Koch, defined by the tendon of Todaro, septal leaflet of the tricuspid valve and coronary sinus, is thus not violated and the conduction system is preserved.
Sizing is based on the area of the septal leaflet. Our preference is to use the Edwards MC3 tricuspid annuloplasty ring (MMCTSLink 162), as it takes into account the natural three-dimensional architecture of the tricuspid annulus [7, 8]. Typically we aggressively downsize. Males usually receive a 28 mm ring and females a 26 mm ring. The ring is seated and sutures are tied (Video 3).
We start tying first at the septal leaflet as we feel that this area of the annulus is most secure. Passive testing is not as effective as with mitral repair as RV pressurization is difficult to achieve unless the pulmonary artery is temporarily occluded. Typically some attempt is made to compress the main pulmonary artery and saline is injected through the tricuspid valve. Doing so allows the adequacy of the repair to be inspected (Video 4).
We close the often thin atrium with (4-0) polypropylene suture with a fine needle using a double layer closure. Felt and pledgeted material are avoided. Bypass is weaned and the transesophageal echo is inspected to confirm the adequacy of the repair.
Frequently we are asked to operate on patients with compromised ventricles. Often, some component of biventricular failure and significant tricuspid regurgitation coexists with left-sided pathology. These patients often require substantial doses of diuretics to maintain euvolemia. Work by Dreyfus has shown that TR in such patients is progressive and is related to annular size [9]. It has become our policy to address tricuspid regurgitation if 2+ or greater TR has been identified by preoperative echocardiography, especially if significant annular dilation is present. We are mindful of intraoperative downgrading. We feel that it is most efficient to perform tricuspid procedures after left-sided work. The heart is allowed to reperfuse and recover from cardioplegic arrest and ischemic time is minimized. Tricuspid annuloplasty is usually straight forward and adds little to the total perfusion time. Once the atrium is closed separation from bypass is typically prompt. The work of several authors has shown that formal ring annuloplasty results in less recurrent TR and is more durable than suture annuloplasty [4, 5, 6] (Graph 1). McCarthy reported on a series of 790 patients undergoing tricuspid annuloplasty. Operative mortality was 6%. Even with formal ring annuloplasty using the Carpentier-Edwards ring and the Cosgrove flexible band, significant (3+/4+) TR was present in 14% of patients early after operation [4]. Risk factors for recurrent TR were found to be higher grade of preoperative TR, nonring annuloplasty, presence of a transvalvular pacing lead and decreased left ventricular function. Of note, the operative mortality for recurrent TR was high at 32%, which reflects how compromised patients with longstanding significant TR can be [4]. This paper taught us that reoperation for TR is not to be undertaken lightly. We treat TR aggressively at the initial operation if it is significant or if we think it will progress.
We occasionally use the De Vega technique for prophylactic annuloplasty on the donor heart during heart transplantation, and in patients undergoing left ventricular assist device placement who have significant TR, as it is slightly faster and does not introduce prosthetic material. However, in the vast majority of patients with significant TR, we have found ring annuloplasty simple, expeditious, reproducible, and durable. Recently we have used the Edwards MC3 annuloplasty system (Photo 1). It was developed by the senior author of this manuscript to take into account the three-dimensional geometry of the tricuspid valve with the hope of improving the durability of tricuspid valve repair. The Mt. Sinai group recently reported on a series of 75 patients who underwent tricuspid annuloplasty with the MC3 [7, 8]. Follow-up at up to 16 months demonstrated 28 (62%) of patients with 0 to trace TR, 17 (38%) with 1+ TR and 1 patient with 2+ TR [7, 8]. Operative mortality was 5.3%. Long-term studies will be required to see if these encouraging short-term results stand the test of time.
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