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Early results of geometric ring annuloplasty for bicuspid aortic valve repair during aortic aneurysm surgery

Open AccessPublished:June 08, 2022DOI:https://doi.org/10.1016/j.xjtc.2022.03.023

      Abstract

      Objectives

      Geometric ring annuloplasty has shown promise during bicuspid aortic valve repair for aortic insufficiency. This study examined early outcomes of bicuspid aortic valve repair associated with proximal aortic aneurysm replacement.

      Methods

      From September 2017 to November, 2021, 127 patients underwent bicuspid aortic valve repair with concomitant proximal aneurysm reconstruction. Patient age was 50.6 ± 12.7 years (mean ± standard deviation), male gender was 83%, New York Heart Association Class was 2 (1-2) (median [interquartile range]), and preoperative aortic insufficiency grade was 3 (2-4). Ascending aortic diameter was 50 (46-54) mm, and all patients had ascending aortic replacement. Forty patients had sinus diameters greater than 45 mm, prompting remodeling root procedures. A total of 105 patients had Sievers type 1 valves, 3 patients had type 0, and 7 patients had type 2. A total of 118 patients had primarily right/left fusion, 8 patients had right/nonfusion, and 1 patient had left/nonfusion. Leaflet reconstruction used central leaflet plication and cleft closure, with limited ultrasonic decalcification in 31 patients.

      Results

      Ring size was 23 (21-23) mm, and 26 of 40 root procedures were selective nonfused sinus replacements. Aortic clamp time was 139 (112-170) minutes, and bypass time was 178 (138-217) minutes. Postrepair aortic insufficiency grade was 0 (0-0) (P < .0001), and mean valve gradient was 10 (7-14) mm Hg. No early and 1 late mortality occurred. Four patients required reoperation for bleeding, and 4 patients required pacemakers. At a mean follow-up of 20 months (maximal 93), there were no valve-related complications, 5 late repair failures prompting valve replacement, and 1 death due to Coronavirus Disease 2019.

      Conclusions

      Geometric ring annuloplasty for bicuspid aortic valve repair with proximal aortic aneurysm reconstruction is safe and associated with good early outcomes. Further experience and follow-up will help inform long-term durability.

      Graphical abstract

      Key Words

      Abbreviations and Acronyms:

      AI (aortic insufficiency), BAV (bicuspid aortic valve)
      Figure thumbnail fx2
      BAV repair with hemi-root replacement. Bicuspid repair using geometric ring annuloplasty and root remodeling with single sinus resection followed by aneurysm repair.
      By using bicuspid ring annuloplasty, leaflet reconstruction, and aortic root remodeling, most types of bicuspid valve defects associated with proximal aortic aneurysms can be repaired with good early results.
      Routine bicuspid valve repair during aortic aneurysm surgery has been difficult for a variety of reasons. Bicuspid ring annuloplasty produces major annular remodeling and equalizes fused and nonfused segmental annular circumferences, facilitating leaflet reconstruction. Together with ascending aortic and selective sinus replacement, bicuspid valve repair can become routine with good early results.
      It now can be argued that autologous repair of the bicuspid aortic valve (BAV) for aortic insufficiency (AI) is the surgical procedure of choice when clinical indications exist.
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      • Schneider U.
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      • Schaefers H.J.
      (Almost) all nonstenotic bicuspid aortic valves should be preserved or repaired.
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      Geometric ring annuloplasty for aortic valve repair during aortic aneurysm surgery: two-year clinical trial results.
      and repair failure (previously a drawback) is decreasing progressively with technical development.
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      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      Valve-related complications are lower than with prosthetic valve replacement,
      • Aicher D.
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      Aortic valve repair leads to a low incidence of valve-related complications.
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      • et al.
      Valve sparing-root replacement with the reimplantation technique to increase the durability of bicuspid aortic valve repair.
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      Bicuspid aortic valve repair: causes of valve failure and long-term outcomes.
      but still require selective application, allowing only a minority of valves to be repaired.
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      • Svensson L.G.
      • et al.
      Long-term outcomes after aortic valve surgery in patients with asymptomatic chronic aortic regurgitation and preserved LVEF: impact of baseline and follow-up global longitudinal strain.
      Two barriers to repair of BAV with associated ascending aortic aneurysm persist, namely, difficulty in repairing some anatomies such as valves with 3 equal sinuses or unicuspid defects
      • Aicher D.
      • Kunihara T.
      • Abou Issa O.
      • Brittner B.
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      • Schafers H.J.
      Valve configuration determines long-term results after repair of the bicuspid aortic valve.
      ,
      • Igarashi T.
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      • Shimizu A.
      • Ehrlich T.
      • Karliova I.
      • Schafers H.J.
      Bicuspidization and annuloplasty provide a functioning configuration to the unicuspid aortic valve.
      and lower repair rates in patients with BAV and proximal aortic aneurysms using traditional reimplantation procedures.
      • Leontyev S.
      • Schamberger L.
      • Davierwala P.M.
      • Von Aspern K.
      • Etz C.
      • Lehmann S.
      • et al.
      Early and late results after David vs Bentall procedure: a propensity matched analysis.
      The major annular remodeling associated with BAV ring annuloplasty specifically addresses the first problem by equalizing the fused and nonfused annuli, while establishing 180° commissural orientation.
      • Si M.-S.
      • Conte J.V.
      • Romano J.C.
      • Romano M.A.
      • Andersen N.D.
      • Gerdisch M.W.
      • et al.
      Unicuspid aortic valve repair using geometric ring annuloplasty.
      Internal geometric ring annuloplasty also facilitates aneurysm replacement, and when coupled with remodeling aortic root replacement
      • Schäfers H.J.
      • Kunihara T.
      • Fries P.
      • Brittner B.
      • Aicher D.
      Valve-preserving root replacement in bicuspid aortic valves.
      eliminates the need for deep external root dissection in the sometimes difficult right coronary sinus area.
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      The purpose of this study was to assess the early results of BAV ring annuloplasty combined with proximal aortic replacement, including root remodeling when appropriate, for management of BAV defects associated with aortic aneurysms during initial application in the United States and Europe.

      Materials and Methods

      From February 2014 to November 2021, 127 consecutive patients underwent BAV repair supported by internal ring annuloplasty with concomitant ascending aortic or root aneurysm replacement in 25 US and 2 European centers (Table 1). The first 6 patients were part of the European regulatory trial,
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      and the rest were postmarket after Food and Drug Administration and CE approval. A waiver of informed consent was obtained from the Institutional Review Board or Ethics Committee of each institution for retrospective analysis of de-identified clinical data. Additionally, an overall waiver was obtained from the WCG Institutional Review Board. This series represents the initial application of internal BAV annuloplasty ring technology in the 27 participating centers. Patient age was 50.6 ± 12.7 years (mean ± standard deviation), male gender was 83%, New York Heart Association Class was 2 (1-2) (median [interquartile range]), and preoperative AI grade was 3 (2-4). Twenty-eight patients (22%) had grade 0-1 AI preoperatively, and the valves were repaired during aneurysm surgery because of low coaptation height or dilated annulus, factors predicting future valve deterioration. The majority (82/127 or 65%) had grade 3 or 4 AI. Average ascending aortic diameter was 50 (46-54) mm, and all patients had graft replacement of the ascending aorta. Forty patients had sinus diameters greater than 45 mm prompting additional remodeling root procedures (Table 1), and 26 of these had selective nonfused sinus replacement. A total of 118 patients had Sievers type 1 valves, 4 patients had type 0, and 5 patients had type 2 defects. A total of 118 patients had primarily right/left fusion, 8 patients had right/nonfusion, and 1 patient had left/nonfusion.
      Table 1Clinical characteristics for patients with bicuspid aortic valve aneurysm
      Clinical characteristicsTotal N = 127
      Descriptive statisticsMean ± SDMedian (IQR)
      Age (y)50.6 ± 12.7
      Represents data with normal distribution by D'Agostino and Pearson test. The change in AI grade after repair was statistically significant, P < .0001.
      51 (40-59)
      Male, N (%)106/127 (83%)
      NYHA Class2 (1-2)
      Ascending aortic diameter (mm)50 (46-54)
      Ascending aortic replacement only, N (%)87 (69%)
      Root procedures for diameter >45 mm, N (%)40 (31%)
      Hemi-root replacements, N (%)26 (20%)
      Aortic clamp time (min)139 (112-170)
      Bypass time (min)178 (138-217)
      Preoperative annular diameter (mm)27.2 ± 3.7
      Represents data with normal distribution by D'Agostino and Pearson test. The change in AI grade after repair was statistically significant, P < .0001.
      Average ring size (mm)23 (21-23)
      Preoperative AI grade3 (2-4)
      Postrepair AI grade0 (0-0)
      Postrepair mean systolic valve gradient (mm Hg)10 (7-14)
      Hospital days to discharge6 (4-8)
      Clinical descriptive characteristics of the 127 patients undergoing BAV repair and concomitant proximal aortic procedures. SD, Standard deviation; IQR, interquartile range; NYHA, New York Heart Association; AI, aortic insufficiency.
      Represents data with normal distribution by D'Agostino and Pearson test. The change in AI grade after repair was statistically significant, P < .0001.
      As described previously,
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      the rings were machined from titanium blocks producing circular base geometry incorporating two 180° sub-commissural posts that flared outward by 10°. The rings were covered with a thin layer of polyester fabric to promote endothelialization while maintaining a low profile (Figure 1, A). By using specially designed ball sizers placed in the coronary sinus (Figure 1, B), ring size was determined as nonfused leaflet free-edge length/1.5, which was correlated with maintaining unchanged intercommissural distance (Video 1). Pathologic annular diameter was measured in 88 patients using a Hegar dilator. Mild to moderate calcification was removed using the ultrasonic aspirator in 31 patients (24%) if localized to the commissures, raphes, or cleft tissue. Severe transmural leaflet calcification, active endocarditis cases, or leaflet defects requiring large pericardial patches were not selected for repair. Rings were sutured sub-annularly into the inflow portion of the valve with 7-13 transannular horizontal mattress sutures of 3-0 or 4-0 coated braided polyester (Tevdek, Teleflex Medical EOM) supported by fine polyester pledgets. A 20-mm half-circle taper needle was ideal for suture placement. Early in the series, polypropylene (Prolene, Ethicon Inc) suture was used, but proved inadequate because of late suture fracture (see “Results”). However, using a high lubricity suture is important to pull the ring tightly up under the annulus, and the annular suture line should be complete, with no gaps, and with bites 2 mm deep to the leaflet-aortic junction above and below the valve. Leaflet reconstruction usually used Schäfers’ methods of central leaflet plication and cleft closure (Figure 2). Video 1 shows a technical BAV repair, and a complete description has been published.
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      Figure thumbnail gr1
      Figure 1A, BAV annuloplasty ring. B, Leaflet ball sizer used in this series.
      Figure thumbnail gr2
      Figure 2A, Typical type 1 BAV is shown with the right-left commissure comprising a complete fusion (fused leaflet raphe) and a thickened fused cusp cleft. B, The leaflet reconstruction is begun by plicating the nonfused cusp to an 8- to 10-mm effective height. C, Spacing sutures are placed from the center of the nonfused cusp across to the fused cusp, equidistant from the commissure, on both sides of the cleft. This sets up the cleft for closure, producing a 2-leaflet valve with similar effective height, geometric height, and free-edge length. Illustration adopted from Schäfers
      • Schäfers H.J.
      Reconstruction of the bicuspid aortic valve.
      with permission. eH, Effective height; gH, geometric height; FEL, free-edge length.
      After completing the valve repair, decisions were made about which aortic segments to replace using established criteria.
      • Svensson L.G.
      • Adams D.H.
      • Bonow R.O.
      • Kouchoukos N.T.
      • Miller D.C.
      • O'Gara P.T.
      • et al.
      Aortic valve and ascending aorta guidelines for management and quality measures.
      In all cases, ascending aortic or root diameter exceeded 45 mm, and ascending aortic replacement was performed with a Dacron graft 5 to 7 mm larger than the ring used in the valve repair, duplicating normal anatomy.
      • Rankin J.S.
      • Bone M.C.
      • Fries P.M.
      • Aicher D.
      • Schafers H.J.
      • Crooke P.S.
      A refined hemispheric model of normal human aortic valve and root geometry.
      ,
      • Crooke P.S.
      • Beavan L.A.
      • Griffin C.D.
      • Mazzitelli D.
      • Rankin J.S.
      A geometric model of the normal human aortic root and design of a fully anatomic aortic root graft.
      If the transverse maximal sinus diameter approached or exceeded 45 mm, a remodeling root procedure was performed using a Valsalva graft, again 5 to 7 mm larger than the annuloplasty ring. If the root enlargement was asymmetrically involving only the nonfused sinus (Figure 3), that sinus was excised, and a slightly less than 180° tongue of the graft was sutured to the sinus, usually starting at the nadir and progressing upward toward the commissures. The graft anastomosis was continued across the top of the fused sinus, often with a single running suture as an aortic “hemi-root” replacement.
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      ,
      • Mazzitelli D.
      • Pfeiffer S.
      • Rankin J.S.
      • Fischlein T.
      • Choi Y.H.
      • Wahlers T.
      • et al.
      A regulated trial of bicuspid aortic valve repair supported by geometric ring annuloplasty.
      Video 2 shows BAV repair with hemi-root replacement. If the aortic root was greater than 45 mm in diameter and both sinuses were dilated, the Valsalva graft was fashioned with 2 approximately equal 180° tongues, and the fused sinus was excised. Usually, each tongue was sutured from its respective sinus base with running sutures completed to the tops of the 2 commissures and tied. The vertical graft incisions were extended as necessary to exactly accommodate commissural heights. Finally, coronary buttons were reimplanted into the side of the graft, using standard techniques. The distal anastomoses were completed to the distal ascending aorta or the aortic arch in a hemi-arch fashion. BAV repair with full aortic root replacement is shown in Video 3. If coronary ostia were anomalous or arose close to a commissure, the coronaries could be left in continuity with the commissures and sinus replacement modified accordingly (Video 4). The technique evolved during the study, and the current recommended approach can be viewed in Video 5.
      Figure thumbnail gr3
      Figure 3After BAV repair, the ring annular sutures are evident, as well as the linear cleft closure and nonfused leaflet plication. An asymmetrically enlarged noncoronary sinus is being excised in preparation for an ascending aortic and hemi-root replacement. Leaflet coaptation is good with similar effective height, geometric height, and free-edge length.
      The standard readings of clinical transesophageal Doppler echocardiograms were used to assess AI grade before and after repair using 5 grades: 0 = none or trivial, 1 = mild, 2 = moderate, 3 = moderately severe, and 4 = severe.
      • Zoghbi W.A.
      • Enriquz-Sarano M.
      • Foster E.
      • Grayburn P.A.
      • Kraft C.D.
      • Levine R.A.
      • et al.
      Recommendations for evaluation of the severity of native valvular regurgitation with two-dimensional and Doppler echocardiography.
      Prerepair AI grades were compared with those obtained after repair with a 2-tailed paired t test. This was not an echocardiographic longitudinal follow-up study, but the “last available” echocardiography data were documented, along with times since the index surgery. Five repair failures occurred during follow-up, and the worse AI grade observed before reoperation was permanently assigned as the last echocardiography in those patients, specifically penalizing reoperation. Mean systolic aortic valve gradients also were measured for the same time points from Doppler velocity data using standard algorithms. Normally distributed data were presented as mean ± standard deviation, and non-normal data as median (interquartile range). Categorical data were described as percentages. Prerepair pathologic annular diameter was compared with “ideal” annular diameter, measured as nonfused leaflet free-edge length/1.5,
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      using a 2-tailed paired t test and linear regression analysis. Freedom from the composite of all-cause death, reoperation, and valve-related complications was analyzed as the most conservative assessment of outcomes, minimizing competing risks. By using the composite outcome variable, time-to-event analysis was performed with Kaplan–Meier techniques and the statistical package of Prism 9.0 (GraphPad Software, Inc). Ninety-five percent confidence limits were calculated by the exponential Greenwood formula. For this descriptive presentation, all survival data were displayed, but the last 10% were differentiated from the other 90% by lighter shading.

      Results

      All BAV repairs were completed successfully, with no intraoperative conversions from repair to prosthetic valve replacement. Ring size was 23 (21-23) mm (Table 1), aortic clamp time was 139 (112-170) minutes, and bypass time was 178 (138-217) minutes. Twenty-six of the 40 root procedures were selective nonfused sinus or hemi-root replacements. Mild to moderately calcified valves were decalcified with the ultrasonic aspirator in 31 patients (24%). Five patients had repair of unicuspid defects.
      • Si M.-S.
      • Conte J.V.
      • Romano J.C.
      • Romano M.A.
      • Andersen N.D.
      • Gerdisch M.W.
      • et al.
      Unicuspid aortic valve repair using geometric ring annuloplasty.
      Intraoperative postrepair AI grade was 0 (0-0) (P < .0001 vs prerepair), and mean valve gradient was 10 (7-14) mm Hg. No 30-day, in-hospital operative mortalities occurred. Four patients required reoperation for bleeding, and 5 patients required pacemakers (4%). Follow-up closing date was November 30, 2021. With a mean follow-up of 20-months (maximal 93 months; maximal in 90% of patients 43 months), 5 patients required aortic valve replacement for interval repair failure.
      The first patient with repair failure experienced rupture of the commissural aspect of a leaflet, thought by the surgeon to reflect placement of the ring post too high in the sub-commissural triangle. Contact between the polyester covering of the ring post and the commissural leaflet tissue seemed to have abraded and ruptured the leaflet. A mechanical valve was placed. This sort of leaflet abrasion has been observed if the ring was sutured to the base of a leaflet (rather than 2 mm back into the annulus), as shown in a nonaneurysmal BAV repair reported previousy
      • Baker J.N.
      • Klokocovnik T.
      • Miceli A.
      • Glauber M.
      • Wei L.M.
      • Badhwar V.
      • et al.
      Minimally invasive aortic valve repair using geometric ring annuloplasty.
      (Figure 4, A). No contact between ring polyester and leaflet tissue should be permitted. Two repair failures in the present series were due to fracture of polypropylene ring looping sutures, with release of the rings into the center of the valve and abrasion of the adjacent leaflets (Figure 4, B). These valves were replaced with mechanical prostheses. The fourth repair failure was thought to be due to a gap in the annular suture line that allowed the ring to move out under the leaflet and abrade it. A mechanical valve was placed. A fifth patient developed breakdown of a raphe closure 2 months after surgery, perhaps due to overzealous fused leaflet thinning, and required a mechanical valve. All 5 reoperated patients recovered uneventfully, and no further annular suture failures have occurred since switching to braided polyester suture in the spring of 2021. Throughout the study period, no valve-related complications occurred. One unvaccinated patient died of Coronavirus Disease 2019 infection 4 months after surgery. At that hospitalization, AI grade was 0, mean valve gradient was 17 mm Hg, and ejection fraction was 0.55.
      Figure thumbnail gr4
      Figure 4A, BAV repair failure due to suturing ring into the base of the nonfused cusp with subsequent leaflet abrasion from ring Dacron. This was a nonaneurysmal BAV repair, reported previously.
      • Baker J.N.
      • Klokocovnik T.
      • Miceli A.
      • Glauber M.
      • Wei L.M.
      • Badhwar V.
      • et al.
      Minimally invasive aortic valve repair using geometric ring annuloplasty.
      B, Video frame from the third repair failure, showing a fractured polypropylene suture, release of the ring toward the valve center, and abrasion of the leaflet.
      A graph from 88 patients illustrating pathologic annular diameter observed before repair versus the “ideal” annular diameter predicted from leaflet free-edge length is shown in Figure 5. A few patients exhibited little annular dilatation, but in most, the pathologic diameter was significantly above the line of identity. On average, pathologic diameter was approximately 5 mm larger than “ideal” (Table 1) (P < .0001), similar to analyses for trileaflet AI. In defining echocardiographic variables at “latest follow-up,” the 5 repair failures cases had the last value before reoperation recorded; 17 patients had not had a follow-up echocardiogram yet or it was obtained elsewhere; in those cases, the operative data were used; 75 were recorded in the first postoperative year; 15 were obtained in the second postoperative year; 5 were obtained in the third postoperative year; 3 were obtained in the fourth postoperative year; and 7 were obtained between 4 and 8 years. Including the 5 repair failures receiving reoperation for grade 3 to 4 AI, the follow-up AI grade was 0 (0-1) (P < .0001 vs preoperative). At the last echocardiography, only 3 patients had stable grade 2 AI, and 119 patients had insignificant grade 0-1 AI. The corresponding mean valve gradient was 12 (8-16). A Kaplan–Meier time to event curve of composite freedom from all-cause death, reoperation, and valve-related complications over time is shown in Figure 6. A Graphical Abstract is included as Figure 7.
      Figure thumbnail gr5
      Figure 5Comparison of pathologic annular diameter (measured with a Hegar dilator before repair) to the “ideal” annular diameter predicted from leaflet free-edge length/1.5 in the 88 patients with prerepair Hegar annular diameter measurements. The line of identity is the heavy thick line, and the linear regression is the thinner line. The regression equation was Y = 0.7886 × X + 9.627 (P < .0001). Mean ± standard deviation for pathologic diameter was 27.3 ± 3.7 mm and for “ideal” diameter was 22.7 ± 1.9 mm (P < .0001). BAV, Bicuspid aortic valve.
      Figure thumbnail gr6
      Figure 6Kaplan–Meier analysis of time-varying events after BAV and proximal aneurysm repair in 127 patients. The composite outcome of interest was survival free of reoperation or valve-related complications. Patients from the early device clinical trials are on the upper right. Blue shading indicates ± 95% confidence limits. Lighter blue shading denotes data from the last 10% of the population. CI, Confidence interval.
      Figure thumbnail gr7
      Figure 7Graphical summary of the study showing the geometry of the BAV annuloplasty ring on the left, an operative photograph of the leaflet repair technique in the center, and the outcomes observed on the right. BAV, Bicuspid aortic valve; CI, confidence interval; AI, aortic insufficiency; AVR, aortic valve replacement.

      Discussion

      Organized efforts to repair insufficient BAVs were initiated by Cosgrove and colleagues
      • Cosgrove D.M.
      • Rosenkranz E.R.
      • Henderson W.G.
      • Barlett J.C.
      • Stewart W.J.
      Valvuloplasty for aortic insufficiency.
      in the late 1980s. However, techniques were rudimentary, usually using sub-commissural mattress sutures for annuloplasty
      • Cabrol A.
      • Guiraudon G.
      • Bertrand M.
      Le traitement de l'insuffisance aortique par l'annuloplastie aortique.
      and leaflet wedge resections for prolapse correction.
      • Cosgrove D.M.
      • Rosenkranz E.R.
      • Henderson W.G.
      • Barlett J.C.
      • Stewart W.J.
      Valvuloplasty for aortic insufficiency.
      Subsequent follow-up in the 1990s revealed unacceptable AI recurrence rates using these techniques,
      • Casselman F.P.
      • Gillinov A.M.
      • Akhrass R.
      • Kasirajan V.
      • Blackstone E.H.
      • Cosgrove D.M.
      Intermediate-term durability of bicuspid aortic valve repair for prolapsing leaflet.
      and efforts to develop practical BAV repair abated. In the late 1990s, Schäfers and coworkers
      • Schäfers H.J.
      • Aicher D.
      • Langer F.
      Correction of leaflet prolapse in valve-preserving aortic replacement: pushing the limits?.
      published a series of patients and illustrations of central leaflet plication for management of leaflet prolapse. Because prolapse is such a prominent feature of bicuspid AI, this innovation was a major enabler for readdressing BAV repair, and the Homburg group
      • Miyahara S.
      • Schneider U.
      • Marganthaler L.
      • Schaefers H.J.
      (Almost) all nonstenotic bicuspid aortic valves should be preserved or repaired.
      recently published their subsequent 20-year experience with excellent long-term results. For replacement of associated proximal aortic aneurysms, these surgeons modified remodeling techniques to their current mature state.
      • Schäfers H.J.
      • Aicher D.
      Root remodeling for aortic root dilatation.
      The approach to BAV repair used in the current article largely uses Schäfers' methods, only with ring annuloplasty added to the repair.
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      Our interest in ring annuloplasty was derived from Carpentier's work,
      • Carpentier A.
      Cardiac valve surgery - the "French correction".
      anticipating that an annuloplasty ring, designed specifically for aortic valve geometry, could improve success and reproducibility of BAV repair.
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      ,
      • Mazzitelli D.
      • Pfeiffer S.
      • Rankin J.S.
      • Fischlein T.
      • Choi Y.H.
      • Wahlers T.
      • et al.
      A regulated trial of bicuspid aortic valve repair supported by geometric ring annuloplasty.
      Annuloplasty is a fundamental component of cardiac valve repair, and full annuloplasty is accepted as a predictor of durability in BAV repair.
      • Jasinski M.J.
      • Kosiorowska K.
      • Gocol R.
      • Jasinski J.
      • Nowicki R.
      • Bielicki G.
      • et al.
      Bicuspid aortic valve repair, outcomes after 17 years of experience.
      As with mitral and tricuspid valve insufficiency, most aortic valves with chronic AI exhibit annular dilatation.
      • Jasinski M.J.
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.
      • Choi Y.-H.
      • Wei L.M.
      • et al.
      Leaflet dimensions as a guide to geometric annuloplasty during aortic valve repair.
      Reduction in annular dimension to a value appropriate for leaflet size is an objective method of ring sizing and a significant advantage of this approach.
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      ,
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      Moreover, remodeling BAV annular geometry to 180° commissures allows routine repair of valves with a variety of commissural orientations, such as intermediate-type BAV with 3 equal sinuses and unicuspid valves.
      • Si M.-S.
      • Conte J.V.
      • Romano J.C.
      • Romano M.A.
      • Andersen N.D.
      • Gerdisch M.W.
      • et al.
      Unicuspid aortic valve repair using geometric ring annuloplasty.
      In so doing, BAV ring annuloplasty provides substantial advantages over other methods of BAV repair.
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      The major ring remodeling that equalizes the fused and nonfused annular segments (no matter the baseline anatomy) allows repair of virtually all BAV defects in the absence of severe calcification. Mild to moderate degrees of calcification also can be managed with the ultrasonic aspirator,
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      converting most insufficient bicuspid valves to repair candidates.
      BAV ring annuloplasty also is advantageous when performed concomitant to remodeling aortic replacement. The procedure can be tailored to specific sinus and coronary anatomy (Video 3). Only the nonfused sinus needs to be replaced when asymmetric sinus enlargement is present (Video 2). This approach comprised approximately two-thirds of our patients with root enlargement and significantly simplified the procedures. Anomalous coronary arteries arising close to a commissure could be left intact, with the sinus suture line coursing outside of the coronary/commissural complex (Video 4). In most cases, remodeling is simpler and more expeditious than reimplantation. The permanent pacemaker rate in this study was 4%, which may be higher than for other techniques. This rate could be reduced in future cases by limiting suture depth into the septal muscle beneath the right/noncoronary commissure, although understanding of conduction system anatomy in BAV defects currently is lacking.
      Separating the valve repair from aneurysm management also has advantages. As discussed, initially creating and maintaining favorable annular geometry allow assessment of repairability as the first step and provide opportunity to address the entire valve pathology before replacing any portion of the aorta. As such, identification of an inadequate repair is not delayed until after the entire aortic procedure, and this aspect may assist the surgeon in the decision to treat more complex valve anatomies. Moreover, external deep aortic root dissection is not required, as with both reimplantation and external bands. In some BAV cases, a right sinus muscle bar can make external annuloplasty difficult, and with internal rings, this problem and the variable of aortic thickness are avoided. With both external bands and circular annuloplasty sutures, the bands can cut through the aorta, disrupting the entire root.
      Aortic ring annuloplasty can also have technical problems. In the first clinical trials 10 years ago, the 2-year repair failure rate was 11%,
      • Mazzitelli D.
      • Fischlein T.
      • Rankin J.S.
      • Choi Y.H.
      • Stamm C.
      • Pfeiffer S.
      • et al.
      Geometric ring annuloplasty as an adjunct to aortic valve repair: clinical investigation of the HAART 300 device.
      mostly from annular suture untying and leaflet injuries due to long annular suture tails. The development of lateral suture fixation
      • Mazzitelli D.
      • Pfeiffer S.
      • Rankin J.S.
      • Fischlein T.
      • Choi Y.H.
      • Wahlers T.
      • et al.
      A regulated trial of bicuspid aortic valve repair supported by geometric ring annuloplasty.
      largely eliminated these complications, and in the current series, the early repair failure rate decreased by two-thirds, although these were the first ring BAV repairs performed by most of the surgeons. Even with early failures, events in the present series were low and similar to most contemporary repair series.
      • Miyahara S.
      • Schneider U.
      • Marganthaler L.
      • Schaefers H.J.
      (Almost) all nonstenotic bicuspid aortic valves should be preserved or repaired.
      ,
      • Malas T.
      • Saczkowski R.
      • Sohmer B.
      • Ruel M.
      • Mesana T.
      • de Kerchove L.
      • et al.
      Is aortic valve repair reproducible? Analysis of the learning curve for aortic valve repair.
      Given the technical nature of all 5 repair failures, it is possible that results could improve further with more experience. Moreover, suture failure with fracture of Prolene annular sutures was found to occur, and together with refined ring sizing strategies (Video 1), the change to braided polyester annular sutures seems to have reduced failure rates to very low levels (Video 5). Thus, compared with other techniques, aortic ring annuloplasty seems to achieve similar outcomes, but has the possible advantage of better reproducibility and greater applicability to more difficult pathologies.
      One repair failure in this series was a technical issue of suturing the ring post too high in the sub-commissural space with abrasion of the commissural leaflet. This type of problem emphasizes the importance of detailed initial surgeon training and continued video proctoring until the learning curve is traversed.
      • Malas T.
      • Saczkowski R.
      • Sohmer B.
      • Ruel M.
      • Mesana T.
      • de Kerchove L.
      • et al.
      Is aortic valve repair reproducible? Analysis of the learning curve for aortic valve repair.
      Similar leaflet abrasion can be produced by suturing rings directly into leaflets (Figure 4, A),
      • Baker J.N.
      • Klokocovnik T.
      • Miceli A.
      • Glauber M.
      • Wei L.M.
      • Badhwar V.
      • et al.
      Minimally invasive aortic valve repair using geometric ring annuloplasty.
      loosely tied sutures, or suture line gaps, emphasizing the importance of tight juxtaposition of each ring under the entire annulus, 2 mm deep to the leaflet-aortic junction. Three repair failures occurred because of fracture of polypropylene annular sutures and annular suture line gaps. In both situations, the rings were released into the center of the valves with subsequent leaflet abrasion (Figure 4, B). Polypropylene initially was used for annular sutures because of its ability to slide and oppose the ring tightly beneath the annulus. Although the incidence of polypropylene suture fracture has been low, it now seems reasonable to use braided polyester sutures instead, which seem to have less tendency toward fracture than the more brittle polypropylene (Video 5).
      Unlike trileaflet aortic rings where liberal downsizing can be useful (and transvalvular gradients are low),
      • Rankin J.S.
      • Wei L.M.
      • Downey R.S.
      • Si M.S.
      • Gerdisch M.W.
      • Kupferschmid J.P.
      • et al.
      Aortic valve repair using geometric ring annuloplasty.
      ,
      • Mazzitelli D.
      • Fischlein T.
      • Rankin J.S.
      • Choi Y.H.
      • Stamm C.
      • Pfeiffer S.
      • et al.
      Geometric ring annuloplasty as an adjunct to aortic valve repair: clinical investigation of the HAART 300 device.
      bicuspid ring true-sizing (or even upsizing if there is any question) is important to minimize higher mean valve gradients (Video 1). Emphasizing the maintenance of inter-commissural dimension, while reducing sinus-to-sinus diameter, optimizes ring size, reduces leaflet plication, and minimizes consequent gradients. Larger sized rings also may reduce suture line stress and suture failure. Shaving of dysplastic leaflets or commissural decalcification is important, along with avoiding overplication
      • Schäfers H.J.
      Reconstruction of the bicuspid aortic valve.
      by maintaining leaflet free-edge length greater than half of the ring circumference (Videos 1, 2, and 5). In special circumstances, however, more plication may be required for reasons of valve competence, and initial mean systolic gradients of 20 to 30 mm Hg have been tolerated well. Over weeks to months postoperatively, such gradients usually fall below 20 mm Hg, possibly because the living leaflet tissue adapts to the hemodynamic milieu.
      • Rankin J.S.
      • Mazzitelli D.
      • Fischlein T.J.M.
      • Choi Y.-H.
      • Aicher D.
      • Wei L.M.
      • et al.
      Bicuspid aortic valve repair using geometric ring annuloplasty: a first-in-humans pilot trial.
      With proper BAV ring sizing, postrepair gradients should be low in the majority of patients (Video 1).

      Study Limitations

      This descriptive study is limited by its observational nature, short follow-up, and small sample size. The echocardiographic follow-up uses only routine clinical data and must be considered as only a first glimpse to rule out large issues, with a future need for proper longitudinal echocardiography analysis. With the exception of the 5 technical repair failures, however, deterioration over time was not detected, and it is important to observe 6 original clinical trial patients doing well almost 8 years after surgery. In this regard, the analysis was not intended as a definitive statement of the propriety of BAV plus aortic aneurysm repair, but rather a first significant description of an approach developed by the authors in the initial phases of US and European clinical application. Since the first regulatory trials of geometric ring annuloplasty, many small problems have been identified and corrected, and technique development now may be asymptotically approaching 100% efficacy. Still, only future case assessment will tell, and more experience and follow-up will be necessary to validate these strategies. Hopefully, the broader anatomic application possible with ring annuloplasty, together with the emerging superiority of BAV repair,
      • Miyahara S.
      • Schneider U.
      • Marganthaler L.
      • Schaefers H.J.
      (Almost) all nonstenotic bicuspid aortic valves should be preserved or repaired.
      will allow autologous BAV reconstruction to be the dominant surgical procedure in the future.

      Conclusions

      Geometric ring annuloplasty for BAV repair combined with proximal aortic reconstruction, including root remodeling, is safe and associated with good early outcomes. The composite of postrepair events is low, and results are consistent with other types of aortic valve repair, but with perhaps greater applicability. The methods are still evolving and could improve further in coming years. Internal geometric rings could form the basis of standardizing BAV repair, as well as extending repair into anatomies that were previously challenging. Further experience and follow-up will be necessary to validate long-term durability.

      Conflict of Interest Statement

      The aortic annuloplasty ring was developed by BioStable Science and Engineering (www.biostable-s-e.com) and is Food and Drug Administration approved in the United States (21 CFR 870.3800) and CE Marked in Europe (G7 103732 0008). Drs Gerdisch, Baker, and Rankin are consultants for this company. All other authors reported no conflicts of interest.
      The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.

      Supplementary Data

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