Emmanuel Lansac

Institute Mutualiste Montsouris, Paris, Ile-de-France, France

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Publications (26)67.38 Total impact

  • Article: Reply to Bozok et al.
    Emmanuel Lansac, Isabelle Di Centa
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 01/2012; · 2.40 Impact Factor
  • Source
    Chapter: An Expansible Aortic Ring for a Standardized and Physiological Approach of Aortic Valve Repair
    12/2011; , ISBN: 978-953-307-600-3
  • Article: Reply.
    The Annals of thoracic surgery 12/2011; 92(6):2303-4. · 3.74 Impact Factor
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    Chapter: Pericardial Processing: Challenges, Outcomes and Future Prospects
    09/2011; , ISBN: 978-953-307-609-6
  • Article: An aortic ring: from physiologic reconstruction of the root to a standardized approach for aortic valve repair.
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    ABSTRACT: We suggest standardizing aortic valve repair using a physiologic approach by associating root remodeling with resuspension of the cusp effective height and external subvalvular aortic ring annuloplasty. A total of 187 patients underwent remodeling associated with subvalvular aortic ring annuloplasty (14 centers, 24 surgeons). Three strategies for cusp repair were evaluated: group 1, gross visual estimation (74 patients); group 2, alignment of cusp free edges (62 patients); and group 3, 2-step approach, alignment of the cusp free edges and effective height resuspension (51 patients). The composite outcome was defined as recurrence of aortic insufficiency of grade 2 or greater and/or reoperation. The operative mortality rate was 3.2% (n = 6). Treatment of a cusp lesion was most frequently performed in group 3 (70.6% vs 20.3% in group 1 and 30.6% in group 2, P < .001). Nine patients required reoperation during a follow-up period of 24 months (range, 12-45), 6 patients in group 1 and 3 patients in group 2. At 1 year, no patients in group 3 presented with composite outcome events compared with 28.1% in group 1 and 15% in group 2 (P < .001). Residual aortic insufficiency and tricuspid anatomy were independent risk factors for the composite outcome in groups 1 and 2. The annulus diameter, the presence of Marfan syndrome, and cusp repair had no effect on aortic insufficiency recurrence or reoperation. A standardized and physiologic approach to aortic valve repair, considering both the aorta (root remodeling) and the valve (resuspension of the cusp effective height and subvalvular ring annuloplasty) improved the preliminary results and might affect their long-term durability. The ongoing Conservative Aortic Valve Surgery for Aortic Insufficiency and Aneurysm of the Aortic Root (CAVIAAR) trial will compare this strategy to mechanical valve replacement.
    The Journal of thoracic and cardiovascular surgery 12/2010; 140(6 Suppl):S28-35; discussion S45-51. · 3.41 Impact Factor
  • Article: Unusual complication of apicoaortic conduit: left main coronary artery thrombosis.
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    ABSTRACT: We report a case of left main coronary artery thrombosis 7 days after aortic valve replacement for native aortic valve regurgitation. The patient had undergone apicoaortic conduit implantation 3 years earlier. The thrombosis resulted from deviation of the cardiac output through the apicoaortic conduit and consequent turbulence of flow in the ascending aorta. Despite thrombus aspiration from the left main coronary artery, the patient never recovered and died 2 days later from multiple organ failure.
    The Annals of thoracic surgery 08/2010; 90(2):628-9. · 3.74 Impact Factor
  • Article: An aortic ring to standardise aortic valve repair: preliminary results of a prospective multicentric cohort of 144 patients.
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    ABSTRACT: Multiplicity of aortic valve repair or sparing techniques results in a lack of standardisation, limiting widespread adoption of such procedures. To treat dilated diameters at the aortic annular base and sinotubular junction while maintaining root dynamics, we propose a standardised and physiological repair approach to the surgical management of aortic root aneurysms, consisting of root remodelling, cusp re-suspension and subvalvular aortic ring annuloplasty. From May 2003 to September 2009, 144 unselected patients with aortic root aneurysms underwent remodelling with external subvalvular ring annuloplasty in 13 centres (21 surgeons). Preoperative aortic insufficiency (AI) > or =grade 2 was present in 63.9% (92), Marfan syndrome in 12.5% (18) and bicuspid valve in 22.9% (33). Cusp repair was performed in 40.3% (58) patients. Valve repair was successful in all but two cases. Repair of cusp prolapse was necessary in 58 patients, significantly more frequent in bicuspid (24/33, 72.7%) than in tricuspid (34/111, 30.6%) valves (p<0.05). Operative mortality was 2.8% (four). Subvalvular ring implantation produced a significant annular base reduction from 27.6+/-2.5 mm to 20.5+/-2.6 mm (p<0.01) without significant mean trans-valvular gradient (7.2+/-1.7 mmHg). During follow-up (median 2.2 years (0.75-4.4, maximum 6.25 years)), five patients died while eight required a re-operation. Six were operated on during our early experience. Strategy for cusp re-suspension evolved over three operative periods, with a significant increase in the rate of cusp repair. From May 2003 to December 2006: eye balling evaluation (15/67 (22.4%)); from January 2007 to August 2008: alignment of cusp free edges (17/38 (44.7%)); and from September 2008 to September 2009: a two-step standardised repair consisting of alignment of cusp free edges and effective height re-suspension (26/39 (66.7%) p<0.05). Freedom from AI> or =grade 2 was 91.3% (115) at the end of follow-up. Implantation of an external aortic ring provides a reproducible technique for aortic valve repair with satisfactory preliminary results. The ongoing CAVIAAR trial (Conservative Aortic Valve surgery for aortic Insufficiency and Aneurysm of the Aortic Root) will compare this standardised repair technique using an expansible aortic ring to mechanical valve replacement.
    European journal of cardio-thoracic surgery: official journal of the European Association for Cardio-thoracic Surgery 03/2010; 38(2):147-54. · 2.40 Impact Factor
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    Article: An expansible aortic ring for a physiological approach to conservative aortic valve surgery.
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    ABSTRACT: Dystrophic aortic insufficiency is characterized by dilation of the aortic annular base and sinotubular junction diameters preventing coaptation of thin and pliable cusps amenable to valve repair. An expansible aortic ring was designed to reduce dilated aortic root diameters to increase valvular coaptation height while maintaining root dynamics. The properties of the device were tested in vitro and in vivo in an ovine model. Expansible rings were composed of an elastomer core covered by polyester fabric. After in vitro analysis of their mechanical properties, the rings were implanted in 6 sheep at both the level of the annular base and sinotubular junction (double subvalvular and supravalvular external aortic annuloplasty). Root dynamics were assessed by using intracardiac ultrasonography before surgical intervention and at 6 months. Histologic, scanning electron microscopic, and mechanical studies were then performed on explanted samples. The expansible ring produced a significant reduction of the aortic annular base and sinotubular junction diameters. Coaptation height was increased from 2.5 +/- 0.7 mm to 6.2 +/- 1.1 mm (P < .001). Mechanical testing on 6-month explanted samples revealed no significant differences in elastic modulus. Dynamics of the root were well preserved. Histomorphologic studies showed incorporation of the material without degradation. Expansible aortic ring implantation produces a significant annuloplasty that increases coaptation height while preserving the dynamics of the aortic root. The effectiveness of the device in treating aortic insufficiency is currently being evaluated in the prospective Conservative Aortic Valve surgery for aortic Insufficiency and Aneurysm of the Aortic Root trial comparing conservative aortic valve surgery versus mechanical valve replacement.
    The Journal of thoracic and cardiovascular surgery 09/2009; 138(3):718-24. · 3.41 Impact Factor
  • Article: A lesional classification to standardize surgical management of aortic insufficiency towards valve repair.
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    ABSTRACT: Aortic valve repair is an alternative to valve replacement for treatment of chronic aortic insufficiency (AI). In order to standardize surgical management, we suggest a classification based on echocardiographic and operative analysis of valvular lesions. Classification was based on the retrospective analysis of chronic AI mechanisms of 781 adults operated on electively between 1997 and 2003. AI was isolated (406 patients (52%)), associated with supra-coronary aneurysm (97 cases (12.4%)), or with aortic root aneurysm (278 patients (35.6%)). Etiologies of valvular or aortic lesions were respectively rheumatic, dystrophic and atheromatous in 17%, 73.6% and 9.4% of cases. Lesional classification is based on the analysis of chronic AI mechanisms defining type I with central jet (354 cases, 45.3%) and type II with eccentric jet (54.7%). Type Ia is defined as isolated dilation of sino-tubular junction (47 supra-coronary aneurysms), and type Ib as dilation of both sino-tubular junction and aortic annular base (233 root aneurysms, 74 isolated AI). The type II associates dilation of sino-tubular junction and annular base to a valvular lesion: IIa cusp prolapse (95 aneurysms, 200 isolated AI); IIb cusp retraction (132 rheumatic AI), IIc cusp tear (endocarditis, traumatic). A lesional classification aims to standardize the surgical management of aortic valve repair: type Ia, by supra-coronary graft; type Ib, by subvalvular aortic annuloplasty associated with the aortic root replacement with a remodelling technique (root aneurysm) or double sub- and supravalvular annuloplasty (isolated AI). For chronic AI type II, aortic annuloplasty associated a remodelling technique or double sub- and supravalvular annuloplasty is combined with the treatment of the cusp lesion (cusp resuspension, cusp reconstruction with autologous pericardium).
    European Journal of Cardio-Thoracic Surgery 06/2008; 33(5):872-8; discussion 878-80. · 2.55 Impact Factor
  • Article: Percutaneous mitral annuloplasty through the coronary sinus: an anatomic point of view.
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    ABSTRACT: We assessed the anatomic relationships among the mitral annulus, coronary sinus, and circumflex artery in human cadaver hearts. Percutaneous posterior mitral annuloplasty has been proposed to treat functional mitral regurgitation on the basis of the proximity of the coronary sinus to the mitral annulus. However, concern remains about the ability to perform a trigone-to-trigone posterior annuloplasty and the potential for compromise of the circumflex coronary artery. Ten hearts were studied after injection of expansible foam into the coronary sinus and circumflex artery. The mitral annulus perimeter, posterior intertrigonal (T1-T2) and intercommissural (C1-C2) distance, and coronary sinus projection on the native annulus (S1-S2) were measured. The spatial geometry of the coronary sinus was correlated with the circumflex artery route and the distance with the native mitral annulus. The projection of coronary sinus annuloplasty achieves at best a commissure-to-commissure annuloplasty 14.5 (6-24) mm behind each trigone: T1-T2: 74 (56-114) mm, C1-C2: 62.2 (48-80) mm, S1-S2: 59.5 (40-80) mm. The coronary sinus was distant from the native annulus (8-14 mm at the coronary sinus ostium, 13.7-20.4 mm at the middle of the coronary sinus, 6.9-14 mm at the level of the great coronary vein). The circumflex artery was located between the coronary sinus and the mitral annulus in 45.5% of cases. This anatomic study highlights the 3-dimensional structure of the coronary sinus and its distance from the native mitral annulus and fibrous trigones. Human anatomic studies are mandatory for the further development of percutaneous mitral repair technology.
    The Journal of thoracic and cardiovascular surgery 03/2008; 135(2):376-81. · 3.41 Impact Factor
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    Article: Further information from a sonometric study of the normal tricuspid valve annulus in sheep: geometric changes during the cardiac cycle.
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    ABSTRACT: In a previous sono-metric study, changes were described that occurred in the normal tricuspid valve during the cardiac cycle. However, the wealth of data available suggested the need for reporting further findings that should contribute to a better understanding of the dynamics of the tricuspid valve. Thirteen sonomicrometry transducers were placed in the hearts of each of seven sheep. Six transducers were placed in the tricuspid annulus (TA), at the base of each leaflet, and at each commissure; three at the tips of the papillary muscles (PMs); three in the free edges of the leaflets; and one transducer was placed at the apex. Distances between transducers, pulmonary and right ventricular pressures, and pulmonary flow were recorded simultaneously. The TA area underwent two major contractions and expansions during the cardiac cycle, reaching its maximum during isovolumic relaxation and its minimum in diastole. The TA height-to-width ratio changed from 8.4 +/- 1.9% to 15.3 +/- 4.2%. The leaflets began to open before end-systole. By the end of isovolumic relaxation, the leaflets had completed 54.1 +/- 13.4% of their opening. The PM and TA planes were not parallel, but were offset by 11.5 +/- 1.9 degrees to 17.8 +/- 2.1 degrees. The PM rotated 6.9 +/- 0.9 degrees with respect to the TA, with 3.1 +/- 1.1 degrees of the rotation occurring during ejection. The tricuspid valve is not a passive structure but rather forms a dynamic part of the right ventricle. Its orifice area changes not only due to the contraction and expansion of its perimeter but also to changes in its saddle shape. Leaflet opening and closure is not simply a response to pressure. The PMs rotate in relation to the TA. These data should impact upon the diagnosis and surgery of functional tricuspid regurgitation.
    The Journal of heart valve disease 10/2007; 16(5):511-8. · 0.81 Impact Factor
  • Article: The papillary muscles as shock absorbers of the mitral valve complex. An experimental study.
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    ABSTRACT: Although it is known that the papillary muscles ensure the continuity between the left ventricle (LV) and the mitral apparatus, their precise mechanism needs further study. We hypothesize that the papillary muscles function as shock absorbers to maintain a constant distance between their tips and the mitral annulus during the entire cardiac cycle. Sonomicrometry crystals were implanted in five sheep in the mitral annulus at the trigones (T1 and T2), mid anterior annulus (AA) mid posterior annulus (PA), base of the posterior lateral scallops (P1 and P2), tips of papillary muscles (M1 and M2), and LV apex. LV and aortic pressures were simultaneously recorded and used to define the different phases of the cardiac cycle. No significant distance changes were found during the cardiac cycle between each papillary muscle tip and their corresponding mitral hemi-annulus: M1-T1, (3.5+/-2%); M1-P1 (5+/-2%); M1-PA (5+/-3%); M2-T2 (2.7+/-2%); M2-P2 (6.1+/-3%); and M2-AA (4.2+/-3%); (p>0.05, ANOVA). Significant changes were observed in distances between each papillary muscle tip and the contralateral hemi-mitral annulus: M1-T2 (1.7+/-3%); M1-P2 (23+/-6%); M1-AA (6+/-3%); M2-T1 (8+/-3%); M2-P1 (10.5+/-6%); and M2-PA (12.6+/-8%); (p<0.05 ANOVA). The distance changes between LV apex and each papillary muscle tip were significantly different: apex-M1 (12.9+/-1%) and apex-M2 (10.5+/-1%) and different from the averaged distance change between the LV apex and each annulus crystal (8.3+/-1%) with p<0.05. The papillary muscles seem to be independent mechanisms designed to work as shock absorbers to maintain the basic mitral valve geometry constant during the cardiac cycle.
    European Journal of Cardio-Thoracic Surgery 07/2007; 32(1):96-101. · 2.55 Impact Factor
  • Article: Dimensional ratios of normal mitral valve structures: a tool for determining the degree of geometric distortion in individual patients.
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    ABSTRACT: BACKGROUND AND AIM of the study: One objective of mitral valve repair is to restore the distorted mitral apparatus geometry to its normal dimensions specific for each patient. Because all dimensions of the normal aortic and mitral valves should be related, it was hypothesized that, in the presence of a normal aortic annulus, it would be possible to determine the dimensions of the structures needed for mitral valve repair. In seven sheep, sonometric ultrasound crystals were implanted at the left and right trigones (T1, T2), lateral annulus (P1, P2), and the tips of the anterior and posterior papillary muscles (Ml, M2). The distances T1-T2, M1-M2, T1-M1, T2-M2, P1-P2, P1-M1, and P2-M2 were measured at end-systole (ES), end-diastole (ED), and maximum and minimum lengths. Using these measured distances, fractional relationships were computed, and the average fractional relationship was used to determine a 'calculated' distance. The 'measured' and 'calculated' distances were then compared using a paired t-test. All fractional relationships were close to 1, with ED 1.00 +/- 0.21, ES 0.99 +/- 0.19, maximum length 0.99 +/- 0.19, and minimum length 0.94 +/- 0.21. The intertrigonal distance (T1-T2) expanded by 4.19 +/- 3.81%, and the transverse diameter (P1-P2) contracted by -6.15 +/- 3.69% from ED to ES. The interpapillary muscle distance (M1-M2) contracted -22.3 +/- 6.5%. The two distances with the least amount of contraction were those of T1-M1 and T2-M2, with contractions of -3.06 +/- 2.39% and -3.27 +/- 1.37%, respectively. P1-M1 and P2-M2 expanded 5.60 +/- 2.89% and 6.84 +/- 3.60% from ED to ES. The mitral valve dimensions and calculated fractional relationships were similar in all sheep. As shown previously, the ratio of aortic annulus diameter (easily measured echocardiographically) to the intertrigonal distance (T1-T2) is 0.79 and 0.80 in humans and sheep, respectively. This distance can be used to determine normal mitral valve geometry and, therefore, preoperatively to calculate the degree of geometric distortion present in individual patients.
    The Journal of heart valve disease 06/2007; 16(3):260-6. · 0.81 Impact Factor
  • Article: Kinking of the atrioventricular plane during the cardiac cycle.
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    ABSTRACT: Systolic descent of the atrioventricular plane toward the relatively stationary left ventricular apex is well described. As the atrioventricular plane includes two separate valvular units, systolic atrioventricular plane displacement should not be homogenous. In 6 sheep, sonomicrometric crystals were implanted at the base of the right coronary sinus, anterolateral and posteromedial fibrous trigones, posterior mitral annulus, left ventricular apex, and the tips of the anterior and posterior mitral leaflets. The aortomitral angle was calculated and related to simultaneous left ventricular and aortic pressures and mitral valve movement. The aortomitral angle was largest at end diastole (150.73 degrees +/- 15.48 degrees ). During isovolumic contraction, it narrowed rapidly to 144.90 degrees +/- 16.64 degrees , followed by a slower narrowing during ejection until it reached its smallest angle at end systole (139.66 degrees +/- 16.78 degrees ). During isovolumic relaxation, the aortomitral angle increased to 143.66 degrees +/- 16.02 degrees at the beginning of diastole. During the first third of diastole, it narrowed again to 141 degrees +/- 16.24 degrees before re-expanding to maximum at end diastole. During systole, the atrioventricular plane descended non-homogeneously toward the apex, with kinking at the hinge between the aortic and mitral annulus plane. This deformation of the atrioventricular plane has relevance in valve surgery.
    Asian cardiovascular & thoracic annals 11/2006; 14(5):394-8.
  • Article: Aortic prosthetic ring annuloplasty: a useful adjunct to a standardized aortic valve-sparing procedure?
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    ABSTRACT: Dilation of aortic annulus, sinuses of Valsalva, and sinotubular junction (STJ) diameters are the characteristic lesions of aortic root aneurysm. The remodeling technique reduces STJ diameter and creates three neosinuses of Valsalva. Alternatively, the reimplantation technique reduces both annulus and STJ diameters to the detriment of aortic root dynamics. Although the remodeling technique is recognized as the most physiological valve-sparing procedure, aortic annulus dilation may jeopardize its results. A standardized approach that combines an external subvalvular aortic prosthetic ring annuloplasty with the remodeling technique is suggested. Eighty-three patients underwent an elective aortic root remodeling procedure, either isolated (group 1, n=34) or combined with an external subvalvular aortic prosthetic ring annuloplasty (group 2, n=49). Preoperative aortic regurgitation was 1.59+/-1.1 (group 1) and 1.97+/-1.3 (group 2) (NS). The aortic annulus was more dilated in group 2 than in group 1 (27+/-2.77 mm vs 26.4+/-2.3 mm, p<0.01). Residual aortic regurgitation > or =grade II was the conversion criteria for aortic valve replacement. Operative mortality was 3.6% (n=3). Intraoperative conversion for valve replacement was 32.7% in group 1 (n=11) versus 4.2% in group 2 (n=2) (p<0.001). In group 1, preoperative annulus diameter was larger for converted than for valve-spared patients (27.6+/-1.7 mm vs 25.2+/-1.5 mm, p<0.02). In group 2, implanted aortic ring significantly reduced annulus diameter (20.6+/-1.8 mm) without significant aortic valve gradient (8.3+/-3 mmHg). Follow-up was 17.2+/-13.4 months (group 1) and 10.41+/-7.95 months (group 2). Reoperation for recurrent aortic regurgitation was 13% in group 1 (n=3) versus 4.2% in group 2 (n=2). Echocardiographic follow-up found residual aortic regurgitation < or =grade I in 17 patients in group 1 (90%) versus 43 patients in group 2 (95.5%) and of grade II in two patients in group 1 (10%) and two patients in group 2 (4.5%). The addition of external aortic prosthetic ring annuloplasty improves the remodeling technique's operative reproducibility and short-term results. Therefore, its use as a systematical adjunct to the remodeling procedure is suggested. However, further long-term evaluation comparing this valve-sparing procedure to composite graft replacement should define the best surgical strategy for aortic root aneurysm.
    European Journal of Cardio-Thoracic Surgery 05/2006; 29(4):537-44. · 2.55 Impact Factor
  • Article: Left ventricular endocardial longitudinal and transverse changes during isovolumic contraction and relaxation: a challenge.
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    ABSTRACT: Left ventricular (LV) longitudinal and transverse geometric changes during isovolumic contraction and relaxation are still controversial. This confusion is compounded by traditional definitions of these phases of the cardiac cycle. High-resolution sonomicrometry studies might clarify these issues. Crystals were implanted in six sheep at the LV apex, fibrous trigones, lateral and posterior mitral annulus, base of the aortic right coronary sinus, anterior and septal endocardial wall, papillary muscle tips, and edge of the anterior and posterior mitral leaflets. Changes in distances were time related to LV and aortic pressures and to mitral valve opening. At the beginning of isovolumic contraction, while the mitral valve was still open, the LV endocardial transverse diameter started to shorten while the endocardial longitudinal diameter increased. During isovolumic relaxation, while the mitral valve was closed, LV transverse diameter started to increase while the longitudinal diameter continued to decrease. These findings are inconsistent with the classic definitions of the phases of the cardiac cycle.
    AJP Heart and Circulatory Physiology 08/2005; 289(1):H196-201. · 3.71 Impact Factor
  • Article: Aortic root dynamics are asymmetric.
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    ABSTRACT: The presence of conformational changes in the aortic root during the cardiac cycle is well known, but precise information on time-related changes at each level of the root is lacking. High-resolution, 3D sonomicrometry (200 Hz) was applied in an acute sheep model. Twelve crystals were implanted in eight sheep at each base (n = 3), commissure (n = 3), sinotubular junction (n = 3) and ascending aorta (n = 3). Under stable hemodynamic conditions, geometric changes of the perimeter of each sinus of Valsalva, sinus height, and twist and root tilt angles were time-related to left ventricluar (LV) and aortic pressures. Expansion of the perimeter of the three sinuses of Valsalva was homogeneous, but in significantly different proportions (p < 0.001): the right sinus expanded (+32.4 +/- 2.4%) more than the left (+29.3 +/- 3.2%), and more than the non-coronary (NC) sinus (+25.8 +/- 1.7%). A similar pattern was found for aortic root height: right greater than left, and left greater than NC sinus (p < 0.001). This asymmetry resulted in changes of the root's twist and tilt angles. Although the twist deformation was consistent for each sheep, no general pattern was found. The aortic root tilt angle (between the basal plane and the commissural plane) was 16.3 +/- 1.5 degrees at end-diastole (angle oriented posteriorly and to the left). During systole, it was reduced by 6.6 +/- 0.5 degrees, aligning the LV outflow tract with the ascending aorta. This tilt angle returned to its original value after valve closure. Aortic root expansion is asymmetric, generating precise changes in its tilt angle. During systole, tilt angle reduction resulted in a straight cylinder that probably facilitates ejection; during diastole, the tilt angle increased, probably reducing leaflet stress. These findings should impact upon surgical procedures and the design of new prostheses.
    The Journal of heart valve disease 06/2005; 14(3):400-7. · 0.81 Impact Factor
  • Article: Anterior mitral basal 'stay' chords are essential for left ventricular geometry and function.
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    ABSTRACT: Among the anterior mitral basal chords, two particularly strong and thick stay chords (SC) remain under tension during the entire cardiac cycle. Collagen fibers of the anterior mitral leaflet (AML) are oriented from insertion of the SC on the AML to the fibrous trigones (FT), suggesting that local stress is directed from the papillary muscles (PM) over the SC and AML to the FT, maintaining left ventricular (LV) geometry. Sonomicrometry crystals were implanted in sheep at the LV apex (A), the anterior (AW) and septal (SW) LV wall, the PM tips (M1 and M2), the SC insertion into the AML (S1 and S2), the posterior (PMA) and lateral (P1 and P2) mitral annulus, the FT (T1 and T2), the tips of the anterior (AL) and posterior (PL) mitral leaflets, and the base of the aortic right coronary sinus (RCS). Changes in distances, areas, and volume were time-related to aortic flow and LV and ascending aorta pressures. Recordings were taken at baseline and after transection of the SC. After transection of the SC, the systolic distance from M1-T1 increased by +0.96 +/- 0.41 mm (p < 0.05) and from M2-T2 by +0.97 +/- 0.42 mm (p < 0.05). The LV length increased at T1-A by +1.14 +/- 0.60 mm (p < 0.05) and at T2-A by +0.97 +/- 0.37 mm (p < 0.05). The aortomitral angle narrowed at end-systole by -3.26 +/- 0.85 degrees (p < 0.05). Transection of the SC reduced dP/dt by -11.20 +/- 5.29% (p < 0.05), maximum aortic flow by -16.89 +/- 7.86% (p < 0.05), and maximum pressure-volume ratio by -10.83 +/- 3.36% (p < 0.05). Transection of the anterior mitral SC did not result in mitral regurgitation but induced significant changes in LV geometry, including narrowing of the aortomitral angle and subsequent deterioration of LV function. The SC are essential for maintaining normal LV geometry and function.
    The Journal of heart valve disease 03/2005; 14(2):195-202; discussion 202-3. · 0.81 Impact Factor
  • Article: External aortic annuloplasty ring for valve-sparing procedures.
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    ABSTRACT: Two different surgical approaches have been suggested for aortic valve-sparing surgery. My colleagues and I suggest combining the advantages of both approaches by adding an external subvalvular prosthetic ring annuloplasty to the remodeling procedure.
    The Annals of thoracic surgery 02/2005; 79(1):356-8. · 3.74 Impact Factor
  • Article: Ischemic mitral valve prolapse: mechanisms and implications for valve repair.
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    ABSTRACT: The aim of this study was to assess the mechanisms of prolapse in ischemic mitral valve regurgitation (MR) and the techniques of valve repair. Out of 121 patients operated upon for ischemic MR, a prolapse was present in 44 patients (36.4%). The operation was performed emergently in four cases (9.1%) and electively in 40 patients (90.9%). Fifteen patients (34.1%) were operated upon within 60 days following acute myocardial infarction. The diagnosis of prolapse had been overlooked by echography in five cases (11.4%). A commissural area was involved as the site of prolapse in 31 cases (70.4%). The mechanism of prolapse was a papillary muscle (PM) lesion in 38 cases (86.4%) (anterior PM: n=8, posterior PM n=36) or a chordal lesion in six cases (13.6%). PM injury was elongation (n=16), or rupture (total n=1, partial n=21, incomplete n=4). The operative technique was mitral valve repair with Carpentier's techniques in 42 cases (95.5%) or replacement in two cases (4.5%). Hospital mortality was 11.4% (n=4). The mean follow-up was to 44.7+/-29.6 months. Overall survival and freedom from reoperation were 68.3+/-9.0 and 89.9+/-5.7% at 5 years, respectively. Freedom from MR equal or > grade 2 was 69.7+/-9.5% at 5 years. The mechanisms of ischemic mitral valve prolapse were variable and tightly linked to the PM anatomy. A reliable mitral valve repair could be achieved in most cases with acceptable mid-term results.
    European Journal of Cardio-Thoracic Surgery 01/2005; 26(6):1112-7. · 2.55 Impact Factor

Institutions

  • 2010–2012
    • Institute Mutualiste Montsouris
      Paris, Ile-de-France, France
  • 2010–2011
    • Hôpital Foch
      Paris, Ile-de-France, France
  • 2009
    • INSERM, GIP CYCERON
      Caen, Basse-Normandie, France
  • 2008
    • Assistance Publique – Hôpitaux de Paris
      Paris, Ile-de-France, France
  • 2002–2007
    • University of Montana
      • The International Heart Institute of Montana Foundation at Saint Patrick Hospital and Health Sciences Center
      Missoula, MT, USA