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Transcatheter Aortic Valve Implantation in Aortic Valve Regurgitation Chapter | 42 467
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authors reported that one patient showed trivial prosthetic valve regurgitation and none of the patients had paravalvular leak of more than mild grade. In addition, Wei et al. reported no major postoperative complications or mortality
during the follow-up period [7].
Symetis ACURATE
Wendt et al. presented their results with the Symetis ACURATE transapical transcatheter aortic valve. They used this self-
expandable transcatheter prosthesis in a series of eight consecutive high-risk patients presenting with pure aortic regurgitation at the West-German Heart Center Essen. Patient mean age was 72.5 ± 8.4 years, and 37.5% of patients were female. All
patients were at highest risk, with a mean logistic EuroSCORE of 34.0 ± 7.9% and the mean Society of Thoracic Surgeons
score was 7.3 ± 3.3%. Before off-label implantation of the Symetis ACURATE prosthesis, two patients had undergone
emergency aortic operation because of acute type A aortic dissection, and both were treated by replacement of the ascending aorta (including root reconstruction) and the aortic arch combined with or without E-vita Open stent graft (Jotec
GmbH, Hechingen, Germany), whereas all other patients experienced primary aortic regurgitation. All patients underwent
successful transapical TAVI with the transapical ACURATE TA device (size small, n = 1, size medium, n = 3, size large,
n = 4) without any intraprocedural complications. Postprocedure aortic regurgitation grade I+ or lower, as revealed by
transesophageal echocardiography and angiography, was present in all eight patients. At 30 days, the stroke incidence and
all-cause mortality rate were 0% [8].
Lotus
In 2016, Wöhrle et al. published a single case report of a 78-year-old patient presenting with severe aortic regurgitation. The
patient also suffered from severe dyspnea New York Heart Association class III, had a severe pulmonary disease, prior stroke,
atrial fibrillation, and a history of repetitive gastrointestinal bleeding. Because of computed tomography and transesophageal
echocardiography measurements, the annulus was measured to be 25.2 mm, with an annulus area of 499 mm2. They decided
to implant a 27-mm Lotus valve. After repositioning, the Lotus valve was in the correct position demonstrating no residual
aortic insufficiency by aortography [9].
DISCUSSION
The present article describes the use of self-expandable, second- or third-generation transcatheter aortic valves in the
treatment of pure aortic valve regurgitation. Currently, all published literature in this regard demonstrates the feasibility of TAVI by the use of the abovementioned devices in high-risk patients presenting with severe aortic regurgitation.
Some of the devices were available only for the transapical approach, and some for both transfemoral and transapical
approaches.
Till date, TAVI has been suggested as an alternative treatment option to conventional aortic valve replacement in
selected patients and has become a more widely practiced and accepted therapeutic option [1,2]. TAVI was primarily developed for patients presenting with aortic valve stenosis valve stenosis; however, although aortic stenosis is
more prevalent, high-risk patients presenting with aortic regurgitation may also benefit from such new catheter-based
techniques.
Aortic calcification is presumably essential for TAVI. The concept of TAVI was originally based on the concept of
valve fixation by displacing the native calcified valve by an oversized transcatheter heart valve. Absence of aortic calcification may result in prosthesis dislodgement. Basically, there are currently two transcatheter valve concepts available: self-expandable and balloon-expandable transcatheter heart valves. The original concept of TAVI was based on
balloon-expandable valves, which by all means depend on aortic calcification. Contrarily, self-expandable valves offer
high and permanent recoil forces, and therefore, this concept is better suited to treat aortic regurgitation. So far, only the
JenaValve technology has received extended CE mark approval for the treatment of aortic regurgitation in September
2013. The JenaValve is now the only TAVI device worldwide approved for the treatment of high-risk or inoperable
patients suffering from severe aortic regurgitation. We decided to use and evaluate the Symetis ACURATE prosthesis in
patients presenting with aortic regurgitation, as we tested this valve in an acute animal study. Within this evaluation, by
nature, all animals presented without any calcification and with normal aortic valves. Even in this setting, we observed
no valve dislocation and a safe fixation in the native, noncalcified aortic annulus [10].
Some of the above-presented concepts offer tactile feedback, as they are implanted through the apex of the left ven-
tricle, and they come with a unique feature of self-positioning of self-aligning. Therefore, even in aortic regurgitation, these
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technologies offering tactile feedback guide the operator for optimal deployment. In addition to this beneficial feature,
some devices offer a partial resheathing or repositioning of the valve until final deployment.
CONCLUSION
In conclusion, some self-expandable transcatheter aortic valve may be off-label used in the treatment of aortic valve
regurgitation. So far, only the JenaValve received CE mark approval for the treatment of aortic regurgitation. All
currently published papers show the basic feasibility of TAVI with the abovementioned concepts in the presence of
aortic regurgitation with low intraprocedural complication rates. However, because of the nature of TAVI in highrisk patients, midterm results are debatable and currently only available for some small series. In the future, the use
of TAVI in high-risk patients presenting with pure aortic regurgitation might increase. Therefore, there are currently
some strong ambitions to harmonize and collect the results of the use of TAVI in pure aortic regurgitation in large
worldwide registries.
REFERENCES
[1] Leon MB, Smith CR, Mack M, Miller DC, Moses JW, Svensson LG, Tuzcu EM, Webb JG, Fontana GP, Makkar RR, Brown DL, Block PC, Guyton
RA, Pichard AD, Bavaria JE, Herrmann HC, Douglas PS, Petersen JL, Akin JJ, Anderson WN, Wang D, Pocock S. Transcatheter aortic-valve
implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med 2010;363(17):1597–607.
[2] Smith CR, Leon MB, Mack MJ, Miller DC, Moses JW, Svensson LG, Tuzcu EM, Webb JG, Fontana GP, Makkar RR, Williams M, Dewey T,
Kapadia S, Babaliaros V, Thourani VH, Corso P, Pichard AD, Bavaria JE, Herrmann HC, Akin JJ, Anderson WN, Wang D, Pocock SJ. Transcatheter
versus surgical aortic-valve replacement in high-risk patients. N Engl J Med 2011;364(23):2187–98.
[3] Cribier A, Eltchaninoff H, Bash A, Borenstein N, Tron C, Bauer F, Derumeaux G, Anselme F, Laborde F, Leon MB. Percutaneous transcatheter
implantation of an aortic valve prosthesis for calcific aortic stenosis: first human case description. Circulation 2002;106(24):3006–8.
[4] Roy DA, Schaefer U, Guetta V, Hildick-Smith D, Mollmann H, Dumonteil N, Modine T, Bosmans J, Petronio AS, Moat N, Linke A, Moris C,
Champagnac D, Parma R, Ochala A, Medvedofsky D, Patterson T, Woitek F, Jahangiri M, Laborde JC, Brecker SJ. Transcatheter aortic valve
implantation for pure severe native aortic valve regurgitation. J Am Coll Cardiol 2013;61(15):1577–84.
[5] Seiffert M, Diemert P, Koschyk D, Schirmer J, Conradi L, Schnabel R, Blankenberg S, Reichenspurner H, Baldus S, Treede H. Transapical implanta-
tion of a second-generation transcatheter heart valve in patients with noncalcified aortic regurgitation. JACC Cardiovasc Interv 2013;6(6):590–7.
[6] Seiffert M, Bader R, Kappert U, Rastan A, Krapf S, Bleiziffer S, Hofmann S, Arnold M, Kallenbach K, Conradi L, Schlingloff F, Wilbring M,
Sch+ñfer U, Diemert P, Treede H. Initial German experience with transapical implantation of a second-generation transcatheter heart valve for the
treatment of aortic regurgitation. JACC Cardiovasc Interv 2014;7(10):1168–74.
[7] Wei L, Liu H, Zhu L, Yang Y, Zheng J, Guo K, Luo H, Zhao W, Yang X, Maimaiti A, Wang C. A new transcatheter aortic valve replacement system
for predominant aortic regurgitation implantation of the J-valve and early outcome. JACC Cardiovasc Interv 2015;8(14):1831–41.
[8] Wendt D, Kahlert P, Pasa S, El-Chilali K, Al-Rashid F, Tsagakis K, Dohle DS, Erbel R, Jakob H, Thielmann M. Transapical transcatheter aortic
valve for severe aortic regurgitation: expanding the limits. JACC Cardiovasc Interv 2014;7(10):1159–67.
[9] Wöhrle J, Rodewald C, Rottbauer W. Transfemoral aortic valve implantation in pure native aortic valve insufficiency using the repositionable and
retrievable lotus valve. Catheter Cardiovasc Intervent 2016;87(5):993–5.
[10] Wendt D, Pasa S, Kahlert P, Delaloye S, Al-Rashid F, Price V, Janosi RA, Borenstein N, Behr L, Konorza T, Erbel R, Jakob H, Thielmann MA.
New self-expandable transcatheter aortic valve for transapical implantation: feasibility in acute and chronic animal experiments. Scand Cardiovasc
J 2013;47(3):145–53.
Chapter 43
FAV = X1+ X2+ X3+ X4+ X5+ X6+ X7+ X8+ X9+ X10,
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David Procedure—Reconstruction of the
Native Insufficient Valve
Jaroslav Benedik, Fanar Mourad, Sharaf-Eldin Shehada
University Hospital Essen, Essen, Germany
Chapter Outline
Background 469
Premise of Functioning AV After Aortic Valve–Sparing Repair 469
Indications for Reimplantation of Aortic Valve 469
Choosing the Right Prosthesis (Measure or Guess?) 470
Mathematical Formula 470
Annulus Sizing 470
Commissure Height 470
STJ-Triggered Sizing 470
Reimplantation of Normal Aortic Valve 473
FAQ 476
Reimplantation of the Tricuspid Aortic Valve
(Structurally Abnormal) 476
Reimplantation of the Bicuspid Aortic Valve 477
FAQ 478
Abbreviations 478
References 478
BACKGROUND
The aortic root remodeling technique was pioneered by Sir Magdi H. Yacoub and was introduced in early 1980s [1]. Aortic
valve (AV) reimplantation was primarily described by Tirone E. David in early 1990s [2]. Over time, the David procedure
has met many innovations including the I–V modifications, El Khoury’s technique [3], and a new modification, which
was recently introduced by our group [4]. Usually straight tube prosthesis was used to replace the enlarged aortic root,
where the AV was reimplanted. More recently, the straight tube prosthesis was replaced by De Paulis Valsalva graft [5].
Reimplantation of the native AV is known as a stable repair technique, which stabilizes the AV in all segments of the ventriculoaortal junction (VAJ), sinuses, and sinotubular junction (STJ). The exact technique allows anatomic placement of all
valve commissures on the same level with good coaptation height and length.
PREMISE OF FUNCTIONING AV AFTER AORTIC VALVE–SPARING REPAIR
After resection of the surrounding aortic tissues, AVs become lose and have no attachments. The technique of reimplanta-
tion (remodeling) would decide whether the valve will be functioning and would determine the life span of the repaired
valve. We believe that a special formula could be applied during aortic valve–sparing repair (AVSR). This “AVSR formula”
supposes to give a successful, long-term results:
where FAV, functioning AV after valve-sparing operation; X, unknown variables; X
, three aortic cusps (presence of
1–3
prolapse, perforation, or calcification); X4, all commissures on the same level (height); X5, sufficient effective height (eH,
which was introduced by Schafers’ [6]); X
, diameter of VAJ, aortic annulus, aortic root and STJ; X10, virtual height of
6–9
commissures/axis of the valve (Fig. 43.1)
INDICATIONS FOR REIMPLANTATION OF AORTIC VALVE
The internationally recognized indication for AV reimplantation is aortic root aneurysm with annular dilatation. The indications have been extended to include patients with connective tissue disorders (e.g., Marfan, Loeys–Dietz syndromes) with
New Approaches to Aortic Diseases from Valve to Abdominal Bifurcation. http://dx.doi.org/10.1016/B978-0-12-809979-7.00043-2
Copyright © 2018 Elsevier Inc. All rights reserved.
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FIGURE 43.1 Virtual height of the aortic valve. The dotted line represents virtual annulus of the valve (connection between nadirs of cusps). The red
line represents the distance between the virtual annulus and the top of each commissure, which should be of same length.
or without dilated aortic annulus, aortic root dilatation, and competent AV. As is already known that a bicuspid aortic valve
(BAV) plays a role in the pathology of aortic wall, the reimplantation of such a valve could also be justified.
CHOOSING THE RIGHT PROSTHESIS (MEASURE OR GUESS?)
The proper prosthesis size should provide the best condition for long-term stability of the reimplanted AV. The stability of
the repair depends mainly on the coaptation length and indirectly on the coaptation height. All components of AV (annulus,
aortic root, and STJ) should be stabilized to achieve a long-term stability of reconstruction.
Mathematical Formula
Tirone E. David published the first article, which described a reimplantation technique of AV, in 1992 [2]. The choosing of
proper prosthesis was based on sophisticated formula by measuring the average heights of the leaflets and the free margins
of all cusps. This formula was not widely adopted because of the difficulty to perform the intraoperative calculations and
was replaced by a simple annulus sizing.
Annulus Sizing
Annulus sizing is the method is used by the majority of surgeons (in the same way as sizing of the aortic annulus in case of
valve replacement). The prosthesis size is estimated by measuring the aortic annulus and adding 3 mm. It is approximately
corresponding to the following statement: “The male patient usually requires a 30-mm prosthesis meanwhile the female
patient would usually require a 28-mm prosthesis.” This method of sizing could be very inaccurate in cases of aortic annulus ectasia or aortic root dilatation.
Commissure Height
It is a relatively simple technique published by De Kerchove [7]. It is based on measuring the height of the noncoronary/
left-coronary commissure. The idea of this technique is to choose the Valsalva prosthesis corresponding to the measured
height (N.B. the prosthesis length of Valsalva sinus portion is the same as the diameter of prosthesis). The graft must be
tailored and cut to bring the three commissures at the same height of the Valsalva prosthesis in what we call a neo-STJ (the
transition of the root part to the tube part of prosthesis). However, it should be mentioned that the graft measurements in
this way does not respond the native configuration of the AV.
STJ-Triggered Sizing
This was a new method for sizing the prosthesis that was introduced by the author [4] (Figs. 43.2 and 43.3). It is based on the
idea that each AV needs its own prosthesis (STJ diameter) for achieving optimal coaptation length and height of the cusps
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FIGURE 43.2 Schematic drawing of sinotubular junction (STJ)–triggered sizing of prosthesis. The black arrow shows the sizing ring. The inner
diameter should correspond to the diameter of prosthesis in the STJ. The black star shows the Trifeet coaptation forceps, creating the desired coaptation
of the three leaflets by holding them in closed position (coaptation length of 1 cm).
FIGURE 43.3 The intraoperative view of freed aortic valve (prepared for aortic valve–sparing repair). The native aortic valve is held in the closed
position using the Trifeet forceps (black star). The tightness of remnant cusp tissue (red arrow) between the Trifeet and the sizing ring (red star) indicates
the correct size of prosthesis. The black arrow shows the commissures.
without creating any prolapse, which usually requires additional plication. The aim of this sizing method is to achieve a competent AV even if the aortic root is dilated. For sizing, two instruments must be used. The special forceps (Trifeet Fig. 43.4),
which creates the coaptation plane, and the phantom-sizing rings (Fig. 43.5) are used to measure the surrounding of the valve,
which corresponds to the size of the Valsalva prosthesis. All three commissures are put on traction sutures and introduced
through the sizing ring. The three cusps are then grasped together with the Trifeet forceps, which creates the required coaptation (8–10 mm). The commissures are put on traction over the sizing ring. The remnant cusp tissue between the forceps and
commissure has to be tightened inside the sizing ring. To determine the optimal size, the sizing maneuver should be repeated
using different sizing rings (Fig. 43.6). The commissures are matched with the marking signs on the upper surface of each sizing ring (indicating a 120-degree orientation) and configuration (symmetry) of the valve should be checked.
FIGURE 43.4 Sizing rings. Different sizing rings (28–34 mm) for the sinotubular junction–triggered sizing.
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FIGURE 43.5 Trifeet forceps. Specially designed three-armed forceps allow gentle gripping of the three cusps and create the plane of coaptation of
the aortic valve with a coaptation length of 1 cm. The red arrow shows the lock mechanism of the forces, which allows gradual coaptation of the three
cusps together.
FIGURE 43.6 Sizing process: an upper view diagrammatic scheme. All three cusps that are held with the Trifeet forceps are represented by the grey
circle, with the big round representing the sizing ring. (A) The sizing ring seems to be too small as the red commissures exceed the plane of sizing ring.
(B) An exact diameter of sizing ring as the green commissures is fitted in the sizing ring. (C) The sizing ring seems to be too big as the red commissures
are very far inside of the sizing ring.
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REIMPLANTATION OF NORMAL AORTIC VALVE
The normal functioning AV has three commissures on the same height. All the three normal cusps open widely in an axis
connecting the left-ventricular outflow tract with the ascending aorta. The valve could be competent or has a moderate
regurgitation (AR). The cause of AR might be because of annular dilatation, STJ dilatation, or both. Preoperative transesophageal echocardiography (TOE) might show no or central jet without eccentric components, prolapsed, or restriction
of cusps.
The reimplantation technique should consider all anatomic relations. The surrounding structures (aortopulmonary fibrous connection underneath the L–R commissure and membranous septum underneath the R–N commissure)
might interfere with the prosthesis in the depth to surround the whole AV with the commissures approaching the
neo-STJ.
Aortic root is fully dissected and freed from the surrounding tissue as much as possible (except for the aortopulmonary
connection and the membranous septum underneath R–N commissure) and AV is checked for any pathology. Both coronary ostia are dissected and prepared for reimplantation as buttons. The wall of the aortic sinus should be excised leaving
approximately 5 mm remnant tissue surrounding the AV and all the three commissures. The stay sutures are placed on top
of each commissure and above each coronary ostium separately.
The suitable prosthesis is chosen using STJ-triggered sizing method (as mentioned above). Configuration (symmetry)
of the valve is checked comparing with signs indicating 120-degree orientations. The known Teflon-pledged sutures are
reduced in our technique only six times and exact placement of these enhances optimal reimplantation of the valve. Three
stitches underneath the commissures would be oriented vertically, minimizing the contact with both leaflets meanwhile the
other three stitches in nadirs are oriented horizontally (Fig. 43.7).
Pre-reimplantation preparation of the prosthesis is essential. The remnant graft material especially underneath R–L commissure, right-ventricle outflow tract, and R–N commissure could oppress the surrounding structures. Cutting through the
prosthesis enhances comfortable reimplantation of the AV. The distance between the subannular Teflon and the top of each
commissure is measured as proposed by El Khoury’s group [3]. The base of the Valsalva graft is cut with a prosthesis cautery
(all three commissures) according to each measured distances, respectively, so that each commissure approaches the neo-STJ
after lowering the graft to aortic base. The remnant prosthesis between commissures is excised in circular shape (Fig. 43.8).
A Prolene (3/0) Normal Aortic Valve purse string suture is placed on the basal part of the prepared prosthesis. Both ends
are passed through the tourniquet (Fig. 43.9). This suture is tied at the end of the procedure (after weaning from cardiopulmonary bypass) under TOE guidance. The subannular sutures are crossed over this purse string suture so that purse string
suture is located underneath the annulus plane directly upon the VAJ (Fig. 43.9). The commissures are temporarily inverted
in the outflow tract, the graft is then lowered down to reach the right position, and the subannular sutures are tied.
The commissures are pulled out in the aortic root. To preserve the natural axis of the valve and respect the virtual
height of all the three commissures (Fig. 43.1), the Trifeet forceps is used again. Perfect coaptation is created and the
three commissures are placed in an appropriate position in the neo-STJ respecting the native orientation of commissures (Fig. 43.10). The remnant aortic wall is fixed by three additional stitches placed in the three nadirs to facilitate
reimplantation (Fig. 43.11). The valve is now fixed at six points (three at the commissures and three nadirs). We have
to take into consideration that any millimeter displacement of the commissures plays a main role in the final appearance of the valve. The 120-degree orientation of commissures matches with the maximal opening of the valve. The
distance between the bottom and the top of the commissure stay stable following the axis connecting the outflow tract
and the ascending aorta.
Reimplantation of the valve is now carried out with three commissural 4/0 Prolene sutures starting in right then left and
finally in the noncoronary sinus. The nadir sutures are tied or even cut out if necessary.
FIGURE 43.7 Orientation of the subannular Teflon-pledged sutures. The six subannular Teflon-pledged sutures are placed underneath the commis-
sures vertically (red arrow) and in the nadirs horizontally (red stars).
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FIGURE 43.8 Cutting of prosthesis. To enhance the safety and comfort of reimplantation, the distance between the subannular Teflon-pledged suture
and the top of the commissure is measured as proposed by El Khoury (red lines) [3]. The rest of the prosthesis is cut in circular shape using electrocautery.
FIGURE 43.9 Subannular purse string suture. Subannular purse string suture (black star) is placed on the bottom of the prosthesis and passed
through a tourniquet (red arrow), which allows adjustment of ventriculoaortal junction and the annulus after weaning from cardiopulmonary bypass under
transesophageal echocardiography guidance.
FIGURE 43.10 Millimeter concept of commissural attachment. All three commissures (black arrows) are placed exactly on the neo–sinotubular
junction (red arrow). The yellow-colored tissue refers to the remnant aortic wall inside the prosthesis. The blue-colored tissue refers to the cusp tissue.
David Procedure—Reconstruction of the Native Insufficient Valve Chapter | 43 475
FAV = C1+ C2+ C3+ C4+ A5+ A6+ A7+ C8+ C9+ C10,
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FIGURE 43.11 Schematic view of nadir trimming. The Trifeet forceps creates the coaptation and the nadirs of the remnant aortic tissue are fixed with
single sutures (black stars).
FIGURE 43.12 Intraoperative view of the high-pressure angioscopy. The silicon line delivers the cold saline (red arrow). Angioscope is in the
middle of the aorta (black arrow). The subannular purse string suture is seen (red star).
Immediately after reimplantation, high-pressure root angioscopy is performed [8]. To facilitate the orientation in
the aortic root, the noncoronary cusp should be marked with a blue marker. The prosthesis is clamped at the end leaving two holes for infusion line and the angioscope. The aortic root is then filled with cold saline under high pressure
(100–200 mmHg) (Fig. 43.12). The AV is inspected under the high-pressure condition. The coaptation and the height of
all cusps are checked (Fig. 43.13). Temporary tightening of the subannular purse string suture could be performed, to
reduce a central defect if present. The possible prolapse of cusps should be fixed immediately after angioscopy, and the
test could be repeated until excellent result is noted. Finally, both coronary ostia are reimplanted in prosthesis using 5/0
Prolene, and continuity of aorta is restored with end-to-end anastomosis using 4/0 Prolene. For such a normal AV, the
AVSR formula mentioned earlier could be modified:
where C
ficient effective height—adjusted; A
, three normal aortic cusps—constant; C4, all commissures on the same level (height)—constant; A5, suf-
1–3
, VAJ, annulus—adjusted; C
6–7
, aortic root, STJ—prosthesis; C10, virtual height of
8–9
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FIGURE 43.13 Aortic valve angioscopy. The aortic valve is visualized during diastole under high-pressure angioscopy. The symmetry of the valve, the
possible prolapse of cusps, and reimplantation suture lines are checked.
commissures/axis of the valve; C, constant by nature (normal cusps), prosthesis (choosing the optimal graft); A, adjustable
(eH—caliper [6]), or basal purse string suture (VAJ, annulus).
The probability of successful reimplantation of such a valve could reach the optimum levels.
FAQ
Q1: Is it possible to use the straight tube graft to reimplant a normal AV?
A: No, in case of the straight tube graft, the distance between the basis and commissure is not stable (possible distortion of
valve) and there are no sinuses present (hemodynamic).
Q2: Could the annulus be stabilized by cutting through the proximal collar of the Valsalva graft?
A: Yes, the distal length of circumference is stable and the definitive width of VAJ is modulated with the purse string suture
on the bottom of the Valsalva graft.
Q3: Is there are any differences between Yacoub and the “novel” David procedure regarding to cutting the prosthesis?
A: Yes, in case of Yacoub procedure the remodeling does not stabilize the aortic annulus (VAJ), and this procedure is a little
bit faster. However, the prosthesis should be fixed underneath the aortic annulus using additional rings or sutures. In case
of the “novel” David procedure, the aortic annulus is stabilized. This procedure requires six additional stitches, which allow
perfect orientation of the valve without the need for additional repair of the leaflets when the AV is structurally normal.
REIMPLANTATION OF THE TRICUSPID AORTIC VALVE (STRUCTURALLY ABNORMAL)
The abnormal AV has additional pathology of the aortic cusps. The suspicion of abnormality could be established in preoperative TOE. The clear signs of abnormality are: eccentric regurgitation jet caused by prolapse or restrictive motion of the
cusp, perforation or large fenestration.
The preparation of aortic root is similar to that of normal AV. The commissural traction sutures are placed and traction is
performed gently; meanwhile, a careful inspection of the valve is performed. The anatomic height of all cusps is measured
and the cusps are carefully examined. At first a valve repair should be performed. After achieving satisfactory repair, the
coronary ostia are dissected and the AV is prepared for reimplantation.
Prosthesis sizing is performed in the same way and reimplantation is carried out as in structurally normal AV (see
section Reimplantation of Normal Aortic Valve). Meticulous care must be taken for the nadir trimming (the deeper reim-
plantation could reduce the prolapse of a single cusp). After reimplantation, a final check of the valve is preformed by
measuring the effective height of each leaflet by using the high-pressure angioscopy. We should bear in mind that the
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