The Bicuspid AV Surgical Considerations Ehud Raanani, MD Cardiothoracic Surgery, Sheba Medical Center Sackler School of Medicine, Tel Aviv University September 12, 2014 Homburg
BAV Repair Congenital variations Dysfunction mechanisms, aortopathy Decision making is complex borderline diameters, to root or not? cusps with moderate calcifications Surgical techniques: Stabilization of the root is important annuloplasty is crucial SCA is not a good solution for annular reduction in the BAV there is no standard technique yet
BAV Prevalence 1 2 % Fusion left-right 86 % right-non 12 % left-non 3 % Associated with: Coarctation PDA Turner s syndrome VSD Supravalvar AS William s syndrome Shone s syndrome
Different angles (120-180 degrees)
Freedom from reoperation BAV repair depending on the orientation of the 2 normal commissures Aicher D et al. Circulation 2011;123:178-185
Perfect BAV <1%
Unicuspid Aortic Valve unicuspid bicuspid R. Anderson
Unicuspid AV Eccentric Opening
Mechanisms of AR in BAV Asc. Aortic aneurysm (STJ) Root aneurysm: STJ Annular dilataion Cusp Prolapse Calcific degeneration Root pathology Cusp pathology
BAV Cusps Pathology Cusp Prolapse Raphe fibrosis and caification Fenestration
Cusp Prolapse
Fibrotic and Redundant Raphe
Tissue Deficiency (geometric height< 18-20mm)
Calcified Raphe Pericardial Patch Partial Cusp Replacement
Freedom from reoperation after BAV repair depending on the use of a pericardial patch Other materials(cor-matrix, Gortex membrane, Cardiocell) Aicher D et al. Circulation 2011;123:178-185
Commissural Pathologies
Bicuspid Aortopathy Prevalence of dilatation 20-80% All aorta segments are larger than in TAV Begins in childhood and is progressive Attributed to hemodynamic and genetic: Autosomal dominant, x-linked, familial modes of inheritances were reported Prevalent in first degree relatives Appears also in normally functioning AV
Histology (cystic medial necrosis) Abnormal processing of ECM fibrillin 1 Detachment of smooth muscle layer from ECM Release of MMP s and tissue inhibitors Disruption of matrix and elastin and all media layer
Patterns of Bicuspid Aortopathy AS, male, age>50 R-N pattern AI, male, <40 y genetic
Abnormal trans-valvular flow pattern: (turbulent flow) TAV BAV no. 1 without raphe Flow velocit magnitu [m/s] BAV no. 1 with raphe BAV no. 2
MRI asymmetric flow jet direction
Age sex morphologic type Patho-physiology (AS, AI)
BAV Aortopathy AHA guidelines
BAV Aortopathy
Risk of late aortic events after an isolated aortic valve replacement for bicuspid aortic valve stenosis with concomitant ascending aortic dilation 153 pts, 40-50mm, 1995-2000, 11.3 mean FU years Ascending aortic surgery was required in five patients (3%) Freedom from aortic interventions at 10 and 15 years was 97 and 94%, respectively. No documented aortic dissection or rupture occurred Pts presenting with AI, freedom from adverse aortic events was significantly lower (88 and 70% 10, 15 years) Girdauskas E..Borger MA et al, Eur J cardiothoracic surgery Nov 2012
Dysfunction of Aortic Root Causing AR Sinu-tubular Dilatation Sinu-tubular +/or Annular Dilatation
To Root or Not to Root
Freedom from reoperation after BAV repair in patients with preoperative AVD of >28 mm depending on the use of root replacement. Significant failure in patients with a > 28 mm Annulus whether they have a SCA or Remodeling Root. Aicher D et al. Circulation 2011;123:178-185
Freedom from reoperation after BAV repair depending on operative technique. Root stabilization is important Aicher D et al. Circulation 2011;123:178-185
Ascending Aorta Replacement
Root Remodeling (Yaacoub)
Remodeling and Correction of Dilated Annulus (D3, Lansac)
Re-Implantation (David)
Reimplantation BAV
What are normal annular diameters? Roman 1987 Kim 1996 Nistri 1999 Varnous 2003 Maselli 2005 Babaee 2007 Tamas 2007 Soncini 2009 Bierbach 2010 Zhu 2011 N 135 110 70 100 50 128 32 52 100 315 1132 Annular Ø STJ Ø STJ/ annulus 24.5 (± 3) 27.5 (± 3) 23.4 (± 2.4) 28.1 (± 3.2) 22.7 (± 2.7) 24.7 (± 2.8) 20.55 (± 3) 31.2 (± 3.7) 24.4 (± 4.1) 22.3±1,4 (20.5-32.4) 25.4 (± 4.1) 26.7±2.2 (31.2-23.4) 1.2±0.1 (1.1-1.3) 21.8±2.4 21± 3 21,6 21±2,8 20,3±8,7 29.5±3.1 27± 4 27,3 25± 3,7 23.4±3,1 1.12 1.2 1.1 1.3 1.1 1.3 1.3 1,3 1,2 1,1 Courtesy E Lansac
BAV have dilated AV junction:25-30mm
Courtesy A. Hamdan
Dilated Aortic Annulus Is Very Common in Patients with BAV and AI Is it Important?
Freedom from reoperation after BAV repair depending on preoperative AVD. Aicher D et al. Circulation 2011;123:178-185
Effect of annulus diameter Six geometries with different annulus diameters Calculated by expanding or shrinking the AA of normal case (24mm) The other dimensions were not changed 20mm 22mm 24mm 26mm 28mm 30mm C-C section
Influence of the geometry on coaptation 5 4 average h c [mm] 3 2 1 h C average h C [mm] 0 15 16 17 18 19 geometric height [mm] 3,5 3 2,5 2 1,5 1 0,5 0 20 22 24 26 28 30 AA diameter [mm]
Influence of the geometry on the max. principal stress The average dimensions case (h G =16.2mm, d AA =24mm) σ max [kpa] has the lowest mechanical stress 1000 900 800 700 600 500 400 300 200 100 0 15 16 17 18 19 geometrial height [mm] σ max [kpa] 900 800 700 600 500 400 300 200 100 0 20 22 24 26 28 30 AA diameter [mm] Maximum principal stress [kpa]
Coaptation vs. effective height Comparison of coaptation during diastole as a function of the effective height The effective height correlates well with valve coaptation The cusps in all the cases with h E <9mm prolapsed during 5 diastole h E h c [mm] 4,5 4 3,5 3 2,5 2 1,5 1 0,5 0 7 9 11 13 h E [mm] daa cusp area
Sub-Commissural Annuloplasty
BAV repair (SCA) with dilated annulus (> 27mm): fails in short term SAME Conclusion: More Failure in Large Annulus p = 0.0003 5 years 34 ± 12% 94 ± 5% 86 ± 10% J. Bavaria et al: STS 2013
Sub-Commissural Annuloplasy (SCA) vs Reimplantation on AI p =0.03 SCA 5 years 92 ± 6% 62 ± 10% Bavaria et al; Presented at STS 2013;
Computer Finite Element Model Stress during peak systole TAV has the largest opening area Highest stress values are found in BAVs with fused cusps Raphe region increases stress magnitudes Max. principal stress [kpa] A TAV BAV no. 2 A BAV no.1 without raphe BAV no.1 with raphe
Flow shear stress during peak systole Higher systolic flow shear stresses are found on the cusps of BAVs The TAV model has the lowest shear stress, specifically on the coapting regions Flow shear stress [Pa] TAV BAV no. 2 BAV no.1 without raphe BAV no.1 with raphe
56
Techniques for Aortic Annuloplasty Carpentier 1983 Frater 1986 Haydar 1997 Izumoto 2002 Hahm 2006 Lansac 2007 Schäfers 2009 Fattouch 2011 Courtesy E Lansac
Lansac 2007 Schäfers 2009
Summary BAV repair for AI, with or without Root Aneurysm, is a good operation in selected patients However, there are relative contraindications to repair where the results are sub-optimal: Significant calcification Need for patch augmentation Inter-commissural angle<160 degrees The case of the Large Annulus (>28mm) specially in Normal Root Diameter Aorta dilatation is frequent and usually involves annular dilatation Annular dilatation should be addressed but SCA is probably not the best technique
Thank you
Ascending Aorta Plication for Moderate Dilatation(40-45mm)
Physiological and standardized approach to aortic valve repair + = Remodeling Reimplantation Remodeling + subvalvular annuloplasty
Valsalva 45 mm Valsalva<40 mm all Ø < 40 mm Remodeling + subvalvular annuloplasty Supra-coronary graft + subvalvular annuloplasty (annulus > 25 mm) Subvalvular annuloplasty (annulus> 25 mm)
Frequency of BAV in AVR pts TAV BAV UAV 45 % 49 % 5 %
70% 45% 33% 45% of patients between 71-80 years 70% of patients between 61-70 years!!
70
Survival After the Bentall Procedure in BAV Survival nearly same as age and sex matched group at 12 years 1 Etz C. D. Ann Thorac Surg 2007;84:1186-94 mount sinai NY
Excellent Aortic Bio-Root replacement outcomes in patients < 60y Desai, annals thorac surg 2011;92 2054-61 U-penn
TAVI Valve-in-Valve Adds More Years to the Index Operation Webb Circ 2010 Bapat JTCVS 2012
Fenestration or Perforation Closure and Stabilisation with pericardium
Aortic root aneurysm Valsalva 45 mm Supracoronary aneurysm Valsalva<40 mm Isolated AI all Ø < 40 mm Remodeling + subvalvular annuloplasty Supra-coronary graft + subvalvular annuloplasty (annulus > 25 mm) Subvalvular annuloplasty (annulus> 25 mm) Courtesy E. Lansac
Freedom from reoperation for SVD All Patients < 60 years
Surgical Solutions Geometry altered by non-pressurized state! Stay sutures
Aortic Annuloplasty
Composite AVR
LVOT and Aortic Root Complex
Co-Location
Remodeling and Correction of Annulus (D3) Dilated
Fibrotic and Redundant Triangular Resection
Aortic Valve Replacement Thromboembolism Anticoagulation/Hemorrhage Structural failure PV endocarditis Incidence of valverelated complications Hammermeister et al, JACC 2000
Prolapse Plication of Cusp Margin
Dilatation of the STJ
Position of His bundle Position of RCA Ostia
Velocity vectors and streamlines TAV BAV no. 1 without raphe Flow velocity magnitude [m/s] BAV no. 1 with raphe BAV no. 2