Feasibility of preservation of subvalvular apparatus in mitral valve replacement with the On-X mechanical valve

Kobe University Hospital, Department of Cardiovascular, Thoracic, and Pediatric Surgery, Kobe, Japan.
The Journal of thoracic and cardiovascular surgery (Impact Factor: 4.17). 01/2007; 132(6):1470-1. DOI: 10.1016/j.jtcvs.2006.08.030
Source: PubMed
Download full-text


Available from: Hiroshi Tanaka, Feb 19, 2015
17 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: The influence of strut position and strut height of Ionescu-Shiley bovine pericardial valves on the degree of left ventricular outflow tract (LVOT) obstruction was studied following mitral valve replacement (MVR) in hypertrophied left ventricles. Left ventricular hypertrophy was created in 6 lambs by constrictive banding of the descending thoracic aorta at 2 weeks of age. MVR was accomplished seven months later utilizing cardiopulmonary bypass and hypothermic cardioplegic arrest. Each animal underwent three consecutive valve replacements with 25-mm bovine pericardial valves randomly inserted in each of the following manners: (1) standard-profile valve with orientation of the struts out of the LVOT; (2) standard-profile valve with a strut oriented into the LVOT; and (3) low-strut profile investigational valve with a strut oriented into the LVOT. Gradients across the LVOT were measured after MVR and then following administration of isoproterenol hydrochloride (0.05 micrograms per kilogram of body weight per minute). No gradient was created with the struts oriented out of the LVOT with or without isoproterenol administration. When a strut was oriented into the LVOT without isoproterenol, the gradients were comparable with the standard- and low-profile valves (7 +/- 2 mm Hg versus 6 +/- 4 mm Hg, respectively). With isoproterenol, however, a significant difference in gradients between the standard- and low-profile valves (65 +/- 20 mm Hg versus 22 +/- 14 mm Hg, respectively) was observed when a strut was oriented into the LVOT. The results show that LVOT obstruction following MVR was related to the orientation of the strut of the bioprosthetic valve, and this obstruction was diminished with a decreased strut height of the Ionescu-Shiley prosthesis.
    The Annals of Thoracic Surgery 10/1986; 42(3):299-303. DOI:10.1016/S0003-4975(10)62739-7 · 3.85 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Frequently portions of the mitral valve and sub-valvular apparatus are left intact during mitral valve replacement to help preserve left ventricular function. We describe a patient with paroxysmal congestive heart failure caused by intermittent entrapment of the subvalvular apparatus in the prosthesis, preventing complete valve closure.
    Journal of the American Society of Echocardiography 01/2001; 13(12):1121-3. DOI:10.1067/mje.2000.107251 · 4.06 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This study evaluates the possible role of the mitral apparatus in left ventricular function after correction of chronic mitral regurgitation. Seventeen patients underwent complete preoperative and early postoperative heart catheterization. Six patients underwent conventional mitral valve replacement (group 1), six mitral valve replacement with preservation of chordae tendineae and papillary muscles (group 2), and five mitral valvuloplasty (group 3). There was no statistically significant difference among the three groups for any hemodynamic parameter as compared before surgery by analysis of variance. After correction of mitral regurgitation the increase in cardiac index was similar for all three groups. Left ventricular end-diastolic volume did not decrease significantly in group 1 (p = NS), but it did in groups 2 and 3 (p less than .005 for both). Left ventricular end-systolic volume increased in group 1 (p less than .025) and decreased in groups 2 and 3 (p less than .01 and .005, respectively). Ejection fraction decreased in group 1 (p less than .005) and did not change in groups 2 or 3 (p = NS). Left ventricular end-diastolic pressure increased in group 1 (p less than .005) and decreased in groups 2 and 3 (p less than .01 for both). These findings suggest that continuity between mitral anulus and left ventricular wall through leaflets, chordae tendineae, and papillary muscles plays a role in left ventricular function after correction of the chronic mitral regurgitation.
    Circulation 10/1983; 68(3 Pt 2):II76-82. · 14.43 Impact Factor
Show more