Intertrigonal Distance Research Articles

The Clinical Development of Percutaneous Heart Valve Technology: A Position Statement of The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), and the Society for Cardiovascular Angiography and Interventions (SCAI)

The Clinical Development of Percutaneous Heart Valve Technology: A Position Statement of The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), and the Society for Cardiovascular Angiography and Interventions (SCAI)

Annular Geometry and Motion in Human Ischemic Mitral Regurgitation: Novel Assessment With Three-Dimensional Echocardiography and Computer Reconstruction

Annular geometry and motion in functional ischemic mitral regurgitation are incompletely understood. Three-dimensional echocardiography demonstrates saddle-shaped annular geometry, but standard methodology does not enable quantification of annular motion. Therefore, a novel technique using three-dimensional echocardiography and computer software was used to characterize alterations in mitral annular geometry and motion in patients with ischemic mitral regurgitation. We developed a computer program to reconstruct the mitral annulus based on spatial coordinates from three-dimensional echocardiography. Data were obtained at end-diastole and end-systole in 7 patients with ischemic mitral regurgitation and 5 normal control subjects. Mitral annular motion was quantified by calculating the displacement area of the annulus between end-diastole and end-systole. Comparison of ischemic mitral regurgitation and control patients revealed differences in annular geometry and motion at end-diastole. Annular perimeter was greater in ischemic mitral regurgitation patients (10.7 +/- 0.7 cm versus 8.6 +/- 0.2 cm in control group; p < 0.03), with increased intertrigonal distance in ischemic mitral regurgitation patients (2.8 +/- 0.3 cm versus 2.1 +/- 0.1 cm; p < 0.06). These changes resulted in increased annular orifice area in ischemic mitral regurgitation patients (9.1 +/- 1.2 cm2 versus 5.7 +/- 0.3 cm2; p < 0.03). Ischemic mitral regurgitation patients had altered annular motion, with reduced movement of the posterior annulus (5.4 +/- 0.7 cm2 versus 8.7 +/- 1.1 cm2; p < 0.03). Computer analysis of data obtained from three-dimensional echocardiography demonstrates altered annular geometry and motion in patients with ischemic mitral regurgitation. Patients with ischemic mitral regurgitation have annular dilatation, with an increase in anterior and posterior annular perimeters; this is accompanied by an increase in the intertrigonal distance and restriction of annular motion.

Semirigid partial annuloplasty band allows dynamic mitral annular motion and minimizes valvular gradients: an echocardiographic study

Background Traditional mitral annuloplasty devices include both rigid rings, which restrict annular motion, and soft rings and bands, which can locally deform. Conflicting data exist regarding their impact on annular dynamics. We studied mitral annuloplasty with a semirigid partial band and with a nearly complete rigid ring. Methods Intraoperative three-dimensional transesophageal echocardiograms (n = 14) and predischarge transthoracic echocardiograms were retrospectively analyzed in patients undergoing mitral valve repair for degenerative disease with either a rigid ring (n = 77) or a semirigid partial band (n = 38). Each transesophageal echocardiogram was analyzed with TomTec three-dimensional software to produce cardiac cycle frame planimetry and to measure device geometry. Actual device sizes provided reference dimensions. Blinded analysis of Doppler data from transthoracic echocardiograms was performed. Results Validation of the quantitative transesophageal echocardiogram methodology revealed a 1.3% ± 0.3% (mean ± standard error of the mean) underestimation of actual linear dimension. With the semirigid partial band, systolic valve orifice area and intertrigonal distance decreased from 6.14 ± 0.37 to 5.55 ± 0.24 cm 2 (−9.6%; p = 0.01) and from 2.69 ± 0.08 to 2.55 ± 0.13 cm (−5.2%; p = 0.03), respectively. Systolic anterior-posterior distance decreased from 2.1 ± 0.10 to 1.95 ± 0.06 cm (−7.1%; p = 0.01) compared with diastole. In contrast, rigid ring orifice area was unchanged (4.12 ± 0.15 to 4.10 ± 0.16 cm 2; −0.5%; p = 0.48) during the cardiac cycle. Transthoracic echocardiography revealed significantly lower mitral inflow gradients with semirigid partial band (mean gradients compared with rigid ring, 4.0 ± 0.3 versus 5.0 ± 0.3 mm Hg; p = 0.02; peak gradients, 8.9 ± 0.5 versus 11.1 ± 0.5 mm Hg; p = 0.01). Conclusions Three-dimensional transesophageal echocardiographic measurements of annular dynamics are valid and reliable when discrete annuloplasty devices are present. In contrast to the rigid ring, the semirigid partial band permits more physiologic geometric changes and is associated with lower postoperative mitral valve gradients.

Annular Remodeling in Chronic Ischemic Mitral Regurgitation: Ring Selection Implications

Background More precise understanding of annular remodeling in the evolution of chronic ischemic mitral regurgitation is needed to provide a more rational basis for optimal annuloplasty ring sizing and selection as well as the design of new reparative techniques. Three-dimensional in vivo data describing these geometric perturbations however are lacking. Using an ovine model of chronic myocardial infarction we determined the three-dimensional distortions of the mitral annulus associated with the development of chronic ischemic mitral regurgitation. Methods Ten sheep underwent placement of radiopaque markers on the left ventricle and mitral annulus as well as placement of snares around the second and third obtuse marginal coronary arteries. After 8 days biplane cinefluoroscopy provided three-dimensional marker data and snare occlusion created an inferior infarction. After 7 more weeks the animals were studied again. Results Severity of mitral regurgitation increased (0.6 ± 0.5 to 2.5 ± 0.7). Septal-lateral (2.99 ± 0.20 cm to 3.64 ± 0.35 cm, maximum dimension) and commissure-commissure (3.71 ± 0.32 cm to 4.40 ± 0.30 cm) mitral annular diameters and the lengths of the muscular (7.77 ± 0.39 cm to 9.51 ± 0.72 cm) and fibrous annular perimeters (3.36 ± 0.37 cm to 3.85 ± 0.39 cm, p < 0.0001 for all) increased while the height of the annular “saddle horn” above a best-fit plane fell (0.73 ± 0.52 cm to 0.57 ± 0.42 cm, minimum dimension, p = 0.01). Conclusions These three-dimensional in vivo data reflect annular remodeling in chronic ischemic mitral regurgitation and suggest that mitral repair in this context should be aimed at preventing further lengthening of the intertrigonal distance, reducing the septal-lateral annular diameter to reestablish adequate leaflet coaptation, and restoring the saddle shape of the annulus.

Does the intertrigonal distance dilate? Never say never

J Thorac Cardiovasc Surg 2002;124:1078-9

Mitral annular size and shape in sheep with annuloplasty rings

Background: Mitral annuloplasty is an important element of most mitral repairs, yet the effects of various types of annuloplasty rings on mitral annular dynamics are still debated. Recent studies suggest that flexible rings preserve physiologic mitral annular area change during the cardiac cycle, while rigid rings do not. Methods: To clarify the effects of mitral ring annuloplasty on mitral annular dynamic geometry, we sutured 8 radiopaque markers equidistantly around the mitral anulus in 3 groups of sheep (n = 7 each: no ring, Carpentier-Edwards semi-rigid Physio-Ring [Baxter Healthcare Corp, Edwards Division, Santa Ana, Calif], and Duran flexible ring [Medtronic, Inc, Minneapolis, Minn]). Ring sizes were selected according to anterior leaflet area and inter-trigonal distance (Physio-Ring 28 mm, n = 7; Duran ring 31 mm, n = 5, and 29 mm, n = 2). After 8 ± 1 days of recovery, the sheep were sedated and studied by means of biplane videofluoroscopy. Mitral annular area was calculated from 3-dimensional marker coordinates without assuming circular or planar geometry. Results: In the no ring group, mitral annular area varied during the cardiac cycle by 11% ± 2% (mean ± SEM; maximum = 7.6 ± 0.2, minimum = 6.8 ± 0.2 cm 2; P ≤ .001). Mitral annular area was fixed in the Physio-Ring group (4.6 ± 0.1 cm 2) and, surprisingly, also static in the Duran ring group (4.8 ± 0.1 cm 2; P = .26 vs Physio-Ring). Furthermore, mitral annular 3-dimensional shape changed in the no-ring group during the cardiac cycle, but not in the Physio-Ring or Duran groups. Conclusions: Mitral annular area and shape did not change during the cardiac cycle after ring annuloplasty, regardless of ring type. Thus mitral annular area reduction, independent of intrinsic ring flexibility, is the chief mechanism responsible for the salutary effects of mitral ring annuloplasty. (J Thorac Cardiovasc Surg 1999;117:302-9)