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DeVega Annuloplasty of the Tricuspid Valve

      The incidence of tricuspid regurgitation (TR) associated with left-sided valve disease, especially mitral, has been described as 8% to 30%. In approximately 80% of the cases, the TR is said to be “functional,” caused by isolated dilation of the annulus, secondary to right ventricular dysfunction, and in the remainder, the lesion is primarily rheumatic (organic), usually with fibrosis of the leaflets and fusion of the commissures.
      • King RM
      • Schaff HV
      • Danielson GK
      • et al.
      Surgery for tricuspid regurgitation late after mitral valve replacement.
      Management of TR during surgery of the mitral and aortic valves is becoming increasingly important.

      Functional Versus Organic Tricuspid Regurgitation

      In 1967, Braunwald and colleagues
      • Braunwald NS
      • Ross J
      • Morrow AG
      Conservative management of tricuspid regurgitation in patients undergoing mitral valve replacement.
      wrote that “in “most” patients with secondary TR, the surgical treatment of mitral valve disease corrects the right sided problems.” It should be expected that by eliminating the triggering factor, after adequate correction of left heart valve disease, the tricuspid regurgitation would regress, but this does not always happen. Furthermore, the results of mitral valve surgery are less favorable in patients with associated right heart disease.
      Hence, the quality of the correction of the left-sided valvulopathy appears fundamental. Any incomplete or unsatisfactory repair will result in persistence or progression of the TR. Even with long-term success of mitral valve surgery, in many cases, there is a progressive increase of tricuspid regurgitation, which may give reason to question its “functional” etiology. Barlow and colleagues have postulated that tricuspid regurgitation is often partly or mainly organic.
      • Pocock WA
      • Antunes MJ
      • Sareli P
      • et al.
      Late postoperative course and complications: emphasis on the “restrictive-dilatation” syndrome.
      Recent evidence demonstrates that functional TR can be ignored only in patients with predictable and significant reduction in pulmonary resistance, which usually follows early correction of left-side pathology. Then when should we repair/replace the tricuspid valve during left-sided valve surgery?
      The evaluation and treatment of the secondary TR continues to be a major problem in the surgical decision-making process. There is no reliable method to judge how much of it is reversible when left-sided problems are corrected. Additionally, there is a lack of reliable methods for quantifying the degree of tricuspid regurgitation, and for assessing true right ventricular function. On the other hand, Dreyfus and coworkers

      Dreyfus G, Bahrami T, John Chan KM, et al.: Secondary tricuspid dilatation with or without regurgitation: should it be repaired? Proceedings of the XIV Annual Meeting of the EACTS, Monaco, October 2002, p 206

      found, very recently, that “secondary” tricuspid annular dilation is present in a significant number of patients with severe mitral disease without TR, which does not resolve with correction of the primary lesion alone. They conclude that in these patients, “tricuspid annuloplasty at the time of mitral valve surgery results in improved functional capacity without any increase in perioperative morbidity or mortality.”

      Assessment Of Tricuspid Valve Regurgitation

      On examination, severe TR is usually associated with a fixed raised jugular venous pressure (JVP), a palpable pulsatile liver and, frequently, peripheral edema. The assessment of the severity of tricuspid valve regurgitation is made by echocardiography and by Doppler identification of the regurgitant jet, and indirectly by detection of hepatic portal venous flow and of right ventricular dilation. During surgery, dilated right atrium and ventricle is an indirect sign of severe TR, especially in the absence of severe pulmonary hypertension.
      In the final instance, the indications for surgery of tricuspid regurgitation in association with mitral valve disease include obviously severe TR preoperatively and worse than expected TR detected intraoperatively. But two major problems remain: what to do with lesser degrees of TR; and how to predict those patients who will return after mitral valve surgery with persistent, bothersome tricuspid regurgitation?

      Valve Replacement Versus Repair

      The major remaining controversies in tricuspid valve surgery are the choice between repair and replacement, the effectiveness of different methods of repair, and, when replacement is required, the type of prosthesis. Only exceptionally will the tricuspid valve need to be replaced as a first procedure, because the valve tolerates well a less-than-perfect repair. Besides, prosthetic tricuspid valve replacement is associated with high rates of mortality and morbidity. Hence, annuloplasty is the surgery of choice and may be achieved with sutures or rings. We believe that implantation of a ring is specifically indicated when there is organic involvement of the tricuspid valve, usually with stenosis, where commissurotomy is also necessary. In “functional” TR, a suture annuloplasty has yielded excellent results in most surgeons' experience.
      Among several types of suture annuloplasty in use, the technique originally described by Dr. Norberto DeVega,
      • DeVega NG
      La anuloplastia selective, reguable y permanente.
      or one of its many modifications, is the most commonly performed. It aims at reducing and fixing the size of the annulus in the segments that are prone to dilation, those corresponding to the anterior and posterior leaflets. Several modifications of the original technique have been described, which were designed to decrease the incidence of suture-related tissue tearing, eventually resulting in a bow-string effect.

      Surgical Technique

      Figure thumbnail fx1
      1Although the right thoracotomy and other so-called mini-invasive or less invasive sternal incisions recently have gained the interest of many surgeons, the most commonly used approach to the left-side heart valves is still the classic median sternotomy. After sternal opening, an inverted-T incision of the pericardium is made. A pericardial cradle is created with three or four silk sutures in the edges of the pericardium on each side, which are pulled up and secured between the sternum and the blades of the retractor.
      Figure thumbnail fx2
      2AAfter confirmation of the indirect signs of tricuspid regurgitation, such as dilated right atrium and ventricle, and administration of heparin, purse-string sutures are placed in the right atrial appendage and in the lateral wall immediately above the inferior vena cava, for venous drainage, and in the distal ascending aorta, for arterial return. Some surgeons prefer to cannulate the superior vena cava directly. IVC, inferior vena cava; PV, right pulmonary veins; PA, pulmonary artery; RA, right atrium; SVC, superior vena cava.
      2B The arterial and venous cannulae are placed and cardiopulmonary bypass is commenced. At 28°C to 30°C, the aorta is cross-clamped and cardioplegia perfused into the aortic root. Snares previously placed around both vena cavae are tightened, to exclude the right atrium from venous blood. Our preferred approach to the mitral valve is the classic incision in the atrial wall, just posterior to the interatrial groove, in which case the right atrium is opened only after completion of the mitral valve surgery. However, in cases of significant biatrial enlargement, we usually access the mitral valve through a longitudinal incision in the interatrial septum after entering the right atrium. The right atrial incision begins next to the atrial appendage, occasionally displacing the superior venous drain, and progresses in an oblique downward direction, to end close to the inferior vena caval drain. Depending on the size of the atrium, it may extend beyond the crista terminalis.
      Figure thumbnail fx3
      3For adequate exposure of the valve, we use a Cooley tricuspid retractor. Alternatively, appropriately placed traction sutures may be used. The anatomy of the tricuspid valve is assessed (the position of the conduction system and of the atrial portion of the membranous interventricular septum should also be noted). A dilated annulus is invariably present. If the leaflets are not involved by the pathological process, the final decision is made to proceed to a DeVega annuloplasty. In cases where the tricuspid leaflets are retracted and there is commissural fusion, a Carpentier ring is preferred.
      Figure thumbnail fx4
      4The classic annuloplasty consists of a double continuous suture which runs along the anterior and posterior annulus, corresponding to the right ventricular free walls, which are mostly involved in this process. The septal portion of the annulus is usually not involved in the dilation process and is spared for protection of the conduction system. In the classic DeVega technique, a 2/0 or 3/0 polypropylene suture is commenced at the posterior extremity of the septal portion of the annulus and continues, in an anticlockwise direction, in the posterior and anterior portions of the annulus. The suture needle penetrates at a depth of 1 to 2 mm, in bites approximately 5 to 6 mm long (A). Once the suture reaches the fibrous trigone, close to the antero-septal commissure, it is reversed over a Teflon® felt pledget. Each bite of the annulus in the second suture line intercalates that of the first one (B). The suture ends where it started and is tied over a Teflon® felt pledget (C). The degree of narrowing of the annulus may be controlled over a Hegar dilator or a valve sizer, between 25 mm and 29 mm, depending on the body surface of the patient, but having in mind that mild stenosis is better tolerated than regurgitation. Though not done routinely, the valve may be tested by injecting cold saline into the right ventricle with a bulb syringe.
      Figure thumbnail fx5
      5In this modified technique, described by us in 1983,
      • Antunes MJ
      • Girdwood RW
      Segmental tricuspid annuloplasty: A modified technique.
      Teflon® felt pledgets are interposed in each bite of the suture in the annulus. We usually start the suture in the septal annulus, about 10 mm from the postero-septal commissure. The suture continues along the posterior and anterior annuli and ends in the central fibrous body, next to the antero-septal commissure. Five or six pledgets are used. The suture is then reversed and another pledget is intercalated in each bite, between those in the first row. In the end, a total of 11 to 13 pledgets will have been used. We have found that tying the knot to obtain a good tightening of the pledgets, resulting in a C-ring-type annuloplasty, leads to a tricuspid orifice which admits two fingertips (diameter of approximately 25-27 mm), without the need for the use of obturators to control the final size of the orifice. We also believe that the addition of the pledgets permits a more uniform distribution of tension, thus resolving the problem of the suture tearing of the annulus with the bow-string effect. Initially, we had used commercially available precut oval pledgets but found these to be too small and now cut them from a patch of Teflon® felt. Each rectangular pledget measures approximately 5 mm × 4 mm and is placed lengthwise (larger dimension along the annulus). To facilitate the handling of the pledgets during penetration by the suture needle, we have developed a special instrument that has a deep cut in the jaws through which the needles are passed (inset).
      Figure thumbnail fx6
      6Intraoperative photograph of a tricuspid valve after a modified DeVega annuloplasty performed according with the technique described in . The two rows of pledgets appear as one single flexible “ring” of felt. The valve was closed by injecting saline with a bulb syringe into the right ventricle

      Conclusion

      Between March 1988 and December 2002, 399 patients who had tricuspid regurgitation associated with mitral valve disease (16% of the total) were subjected to tricuspid valve surgery at our Department. The frequency of tricuspid annuloplasty concomitant with mitral valve surgery increased to 26.4% in the past 5 years. Only three patients had valve replacement. The remainder had annuloplasty, 26 with implantation of a ring and 370 by a modified DeVega annuloplasty.
      • Antunes MJ
      • Girdwood RW
      Segmental tricuspid annuloplasty: A modified technique.
      The latter was performed by all surgeons in the Department, including senior residents. The 30-day mortality was identical (1.3%) for patients who had tricuspid annuloplasty and for those who did not have tricuspid valve surgery. Only two patients required reoperation for persistent or recurrence of severe TR. No case of dehiscence of the suture was identified.
      Thus, in our experience, the modified DeVega tricuspid annuloplasty proved to be a safe procedure for the management of secondary tricuspid regurgitation. It is technically easy and reproducible even by relatively inexperienced surgeons. In our view, it should be used in all patients with more than mild “functional” tricuspid regurgitation. We
      • Antunes MJ
      Segmental tricuspid annuloplasty revisited (letter).
      have recommended and followed this policy for more than a decade with encouraging results, inasmuch as we have observed a low rate of late reoperations. Recent evidence may suggest that it should be used “prophylactically” even in patients with annular dilation in absence of significant regurgitation.
      We have reserved rigid ring annuloplasty (Carpentier-Edwards) for patients with organic tricuspid regurgitation with commissural fusion requiring commissurotomy, where reshaping of the valve is fundamental. Primary valve replacement has been necessary only in a very small number of patients with severe destruction of the valve caused by infective endocarditis.

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        • Schaff HV
        • Danielson GK
        • et al.
        Surgery for tricuspid regurgitation late after mitral valve replacement.
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        • Ross J
        • Morrow AG
        Conservative management of tricuspid regurgitation in patients undergoing mitral valve replacement.
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        • Antunes MJ
        • Sareli P
        • et al.
        Late postoperative course and complications: emphasis on the “restrictive-dilatation” syndrome.
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        • DeVega NG
        La anuloplastia selective, reguable y permanente.
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        Segmental tricuspid annuloplasty: A modified technique.
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