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functional tricuspid valve regurgitation ( tr ) associated with mitral valve disease has not been considered to be serious because it can be improved after the mitral valve lesion is surgically managed . in patients undergoing mitral valve surgery , an isolated tricuspid valve surgery for remnant or aggravated severe
tr usually indicates a poor outcome with high perioperative mortality , poor survival , and no significant improvement in functional capacity .
tricuspid annuloplasty ( ta ) without a ring prosthesis has shown a relatively high recurrence rate of tr .
compared with it , ring annuloplasty for functional tricuspid valve regurgitation improved the long - term clinical outcome and decreased the recurrence rate of tr .
tricuspid ring annuloplasty is usually performed with many interrupted mattress sutures to affix the ring to the annulus .
however , incorrect suturing in the annulus may poorly fix the ring to the annulus and result in uneven plication of the dilated annulus , resulting in remnant tr . with this concern
, we performed a ring annuloplasty using the continuous suture technique and assessed the clinical outcome of the ring annuloplasty for functional tr .
from may 2009 to july 2010 , 20 patients ( male / female , 8/12 ; mean age , 60 years ) with functional tr underwent tricuspid ring annuloplasty using a continuous suture technique .
the indications for tricuspid ring annuloplasty were mild to severe tr , marked annular dilatation ( tricuspid annulus diameter 4 cm or more by echocardiography ) irrespective of any tr grade .
nineteen of them had functional tr without an organic change in the valve leaflet and one patient had tr with chordal rupture secondary to blunt chest trauma .
four patients had isolated tr and 16 had functional tr secondary to left heart valve disease or valve surgery .
ten patients were in more than new york heart association ( nyha ) class iii ( table 1 ) .
the last postoperative echocardiographic results , which were available in 16 patients , were obtained more than 6 months postoperatively . after a median sternotomy
, cardiopulmonary bypass was initiated with a standard aortic cannula and two vena cava cannulas .
the ring annuloplasty was performed on an arrested heart in 17 patients and on a beating heart in three . for the ring annuloplasty
two septal sutures at the anteroseptal and posteroseptal commissures with 2 - 0 polypropylene were placed and then the suture was passed through the two markers of the ring .
the ring was lowered down to the annulus and one arm of each suture was passed along the septal annulus in an over - and - over fashion and they were tied when they met .
the other arm of each suture was passed along the anterior and posterior annulus and then tied . in this way
continuous values are expressed as the meanstandard deviation and were compared by paired and unpaired t - tests .
categorical variables were analyzed by fisher 's exact test using cross tabulation , and categorical ordinal variables were compared by the wilcoxon signed rank test .
from may 2009 to july 2010 , 20 patients ( male / female , 8/12 ; mean age , 60 years ) with functional tr underwent tricuspid ring annuloplasty using a continuous suture technique .
the indications for tricuspid ring annuloplasty were mild to severe tr , marked annular dilatation ( tricuspid annulus diameter 4 cm or more by echocardiography ) irrespective of any tr grade .
nineteen of them had functional tr without an organic change in the valve leaflet and one patient had tr with chordal rupture secondary to blunt chest trauma .
four patients had isolated tr and 16 had functional tr secondary to left heart valve disease or valve surgery .
ten patients were in more than new york heart association ( nyha ) class iii ( table 1 ) .
the last postoperative echocardiographic results , which were available in 16 patients , were obtained more than 6 months postoperatively .
after a median sternotomy , cardiopulmonary bypass was initiated with a standard aortic cannula and two vena cava cannulas .
the ring annuloplasty was performed on an arrested heart in 17 patients and on a beating heart in three . for the ring annuloplasty
two septal sutures at the anteroseptal and posteroseptal commissures with 2 - 0 polypropylene were placed and then the suture was passed through the two markers of the ring .
the ring was lowered down to the annulus and one arm of each suture was passed along the septal annulus in an over - and - over fashion and they were tied when they met .
the other arm of each suture was passed along the anterior and posterior annulus and then tied . in this way
continuous values are expressed as the meanstandard deviation and were compared by paired and unpaired t - tests .
categorical variables were analyzed by fisher 's exact test using cross tabulation , and categorical ordinal variables were compared by the wilcoxon signed rank test .
the surgical data are described in table 2 . there was no perioperative mortality or any conduction problems .
the nyha class of the patients improved and the grade of tr was reduced to less than mild after the operation . after the ring annuloplasty using the continuous suture technique , perioperative echocardiographic values were significantly improved ( table 3 ) . at the mean follow - up duration , none has aggravation of the degree of tr or the annular dimension ( table 4 ) .
in an early study , braunwald et al .   suggested that secondary tr resolves after mitral valve replacement ( mvr ) and a concomitant tricuspid procedure is not needed .
however , nowadays , it is accepted that tr might not improve after mitral valve surgery and even regurgitation might aggravate as much as 20 years later [ 7 - 10 ] . although there is no complete consensus on the guidelines for tricuspid valve ( tv ) repair , tv repair is usually indicated for severe tr in patients undergoing mitral valve surgery , concomitant tv repair with a ta diameter > 40 mm or moderate tr , symptomatic functional tr despite medical management , or symptomatic isolated tr late after left - sided valve surgery .
however , the american college of cardiology / american heart association guidelines do not clearly recommend tv repair when tr is less than severe in patients undergoing mitral valve surgery [ 11 - 13 ] .
in general , a more aggressive concomitant tricuspid annuloplasty is recommended at the initial major procedure because the delayed secondary tr and reoperation for residual tr show a poor outcome [ 14 - 17 ] .
the most common finding of functional tr is an annular dilatation , which subsequently disturbs coaptation of tricuspid leaflets , secondary to the right ventricular dilatation .
several methods such as suture annuloplasty , ring annuloplasty , annuloplasty using tissue materials , and even tricuspid valve replacement have been used for elimination of functional regurgitation .
recent studies have demonstrated that ring annuloplasty is the most effective of the techniques , but 14% of patients with ring annuloplasty had remnant or recurrent tr of 3 to 4 + .
we believe that the early residual regurgitation was related to the suture technique for ring implantation .
the usual suture technique for ring implantation is interrupted mattress sutures that are placed along the tricuspid annulus and enable gathering up the annulus , resulting in a reduction in annular size .
however , when the annular plication is not made with the continuous suture technique , the suture can be released before tying and the annular plication length be redistributed .
we concluded that interrupted sutures make it difficult to adjust the annulus size by the areas of the anterior and posterior leaflets but a continuous suture can be easily performed to allow the adjustment of the size to fit the leaflet area .
tr is strongly related to the annulus dimension : tr was seen when the dimension was larger than 34 mm . in our study ,
the preoperative mean annulus dimension measured by echocardiography was 31.7 mm and even a tricuspid annulus measured 22 mm in diameter showed moderate regurgitation .
postoperatively , the mean annular dimension was 19.8 mm and all the patients revealed less than mild regurgitation , which even 6 months later was still not aggravated in any of the patients .
in addition , the ring annuloplasty improved the postoperative hemodynamic values and did not result in perioperative mortality or conduction problems .
these results suggest that the continuous suture technique for tricuspid ring implantation is safe and effective .
this study is limited by the small number of patients and short study duration ; a report on longer - term surgical outcomes is needed .
various methods of tricuspid annuloplasty have been used to manage tr . to obtain better outcomes ,
a ring prosthesis should be used when tricuspid annuloplasty is performed . instead of the interrupted mattress suture technique using many sutures , a continuous suture technique for the ring implantation in tricuspid annulus
therefore , this method is thought to be a useful way of performing tricuspid ring annuloplasty .
backgrounda ring implantation in the tricuspid annulus requires many interrupted mattress sutures for correction of tricuspid regurgitation ( tr ) . in this study , 
 tricuspid ring annuloplasty was performed by 2 - 0 polypropylene continuous suture instead of multiple interrupted 2 - 0 polyester mattress sutures , and the efficacy of the method was evaluated.materials and methodsthis study included 20 patients who underwent tricuspid ring annuloplasty by continuous suture between may 2009 and july 2010 . 
 four of the patients had an isolated tr , and the rest had a left - sided cardiac lesion . 
 the concomitant tricuspid annuloplasty was performed after the left - sided heart surgery was completed and a duran flexible ring prosthesis was used.resultsthere was no perioperative mortality or conduction problem . 
 more than a moderate degree of tr was improved to less than a mild degree after the procedure . 
 after the ring annuloplasty , the right atrial volume decreased from 123.769.2 ml to 74.537.4 ml , and the mean right atrial pressure was lowered from 18.712.2 mmhg to 8.95.5 mmhg.conclusionthe continuous " over and over " suture may be a useful procedure for fixing the ring to the annulus and making an intentional annular placation in performing tricuspid ring annuloplasty .