Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MITRAL VALVE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed1986

[Doppler echocardiography determination of the pressure gradient and valve orifice area in mitral valve stenosis].

Pressure gradient and orifice area of stenosed mitral valves can be determined with Doppler echocardiography using the modified Bernoulli equation and the pressure half-time method, respectively (Figures 1 and 2). There was a close linear correlation between Doppler-echocardiographically determined pressure gradients and valve orifice areas with those obtained by invasive methods. In this study, in 85 patients with mitral stenosis of various severity, the valve orifice areas, as derived by the two methods respectively, correlated well (y = 0.89x + 0.15) with a correlation coefficient r = 0.96 and standard error of the estimate SEE = 0.12 cm2 (Figure 3). The correlation was not influenced by the prevailing cardiac rhythm, ventricular function, left ventricular mass or coexistent mitral or aortic regurgitation (Table 1). Accordingly, the Doppler echocardiographic method also appears applicable in the presence of concomitant mitral and aortic regurgitation which precludes an exact determination of valve orifice area with invasive methods. The Doppler echocardiographic method is currently so well validated that it can be regarded as a reliable noninvasive procedure for determination of the severity of mitral stenosis.

Blood Flow Velocity↗
PubMed1996

[Valve reconstruction for mitral valve insufficiency. Aspects of surgical technique].

In mitral regurgitation it is undoubtful that reconstruction of the valve aims in functional better results with low risk for the patients. Due to patho-anatomic diversity it is not only necessary to reconstruct individually chordae and leaflets but also to choose selectively the kind for a proper annular reconstruction method. If after repair of the moving parts of the valve there is a central reflux persistent an annular reconstruction should be performed such as De Vega-plasty, whereas an excentric regurgitation makes the implantation of an annular ring mandatory. By this differential approach the risk for persistence of mitral insufficiency is diminished postoperatively.

Adult↗
PubMed2003

The outcome and criteria for mitral valve surgery in patients with ischemic mitral regurgitation.

OBJECTIVES: Mitral valve surgery for the correction of mitral regurgitation (MR) in patients with ischemic heart disease has been associated with poor prognosis. The criteria for selecting an appropriate surgical procedure are not clearly defined. The objectives of this study were to clarify the criteria for mitral valve manipulation and the outcome in patients with ischemic MR. METHODS: Twenty patients with ischemic MR were proposed for surgery. Ten of them (group A) had grade II MR and underwent isolated coronary artery bypass grafting (CABG). The remaining 10 patients with grade III or more MR underwent both CABG and mitral valve repair (group B). Postoperative left ventricular function and outcome were compared. RESULTS: Preoperative left ventricular end-systolic volume index (LVESVI) in group A was significantly smaller, while preoperative ejection fraction (EF) was almost equal between the groups. EF demonstrated a significant improvement in group A postoperatively, but no changes in group B. Two of group B died following surgery. The other patients were successfully treated with surgery which diminished MR. Congestive heart failure (CHF) developed in 2 patients of group B during follow-up and in none of group A. The 5-year freedom from CHF and the 5-year survival rate in group A were significantly greater than those in group B. CONCLUSIONS: Deterioration of mitral valve function, which necessitated mitral valve repair, was more frequent in the impaired and enlarged hearts. Although mitral repair was beneficial for diminishing MR and New York Heart Association, postoperative course in patients with ischemic MR depended on the preoperative LVESVI.

Aged↗
PubMed2003

[Preservation of the entire mitral subvalvular apparatus during mitral valve replacement in patients with mitral stenosis].

OBJECTIVE: To evaluate the surgical technique and the effect of preservation of the entire mitral subvalvular apparatus during mitral valve replacement (MVR) in patients with mitral stenosis. METHODS: MVR was performed on 56 patients with mitral stenosis. Of them, 11 had complete preservation of the entire mitral subvalvular apparatus (group A) with the technique of preservation of 'button-shaped' transplantation, 25 had the preservation of the posterior leaflet only (group B), and the other 20 underwent the conventional MVR (group C). Pre- and postoperative hemodynamic parameters were measured to determine the left ventricular performance. Echocardiography was performed preoperatively, at the time of discharge, and 3 to approximately 6 months postoperatively to determine the dimensions and ejection function. RESULTS: Cardiac index, stroke volume index and left ventricular stroke work index postoperatively in group A were better than those in group B and C (P < 0.05). Echocardiographic measurements postoperatively showed the increase of LVESD, LVEDD in group B and C, but a better LVL and LVFS in group A (P < 0.05), and LVEF was more pronounced in group A (P < 0.05). There appeared a long cross-clamp time in group A, but the total CPB time was not significant among the three groups. CONCLUSION: The surgical skills of preservation with 'button-shaped' transplantation may be a practical choice for patients with mitral stenosis. The preservation of entire mitral subvalvular apparatus improves the left ventricular functions after MVR in patients with mitral valve stenosis.

Adolescent↗
PubMedDate not supplied

Pathological aspects of explanted homograft mitral valve.

BACKGROUND: Homograft mitral valve replacement is an alternative therapeutic approach to prosthetic or bioprosthetic valve replacement. The present paper documents the pathological changes of explanted homograft mitral valve. METHODS: We examined six explanted homograft mitral valves, which were taken out 6 weeks to 60 months following valve replacement procedure. Gross examination of the specimens was done, and representative sections were evaluated using haematoxylin-eosin, Masson's trichrome, Verhoeff's van Gieson and von Kossa stains. RESULTS: On gross examination, the valves showed leaflet calcification and chordal rupture at the tip of the papillary muscles in three cases each. Microscopically, the valve leaflets appeared as aneucleated structures with loss of endocardial lining and lack of nuclear details. The collagenous skeleton was largely preserved. The papillary muscles underwent coagulative necrosis and lacked significant inflammatory infiltrate. One case had a few macrophages at the periphery of myonecrosis, while two cases revealed focal foreign body giant cell reaction. Foci of dystrophic calcification within the areas of myonecrosis were present in three cases. CONCLUSION: Homograft mitral valve undergoes degenerative changes in the recipient, some of which can be attributed to ischaemia.

Adolescent↗
PubMed1985

Flail mitral valve syndrome: comparison with chronic mitral regurgitation of other etiologies.

Thirty-nine patients with symptomatic severe mitral regurgitation (MR) were studied by cardiac catheterization and two-dimensional echocardiography (2DE) prior to mitral valve replacement. A flail mitral valve was found at surgery in 23 patients (group 1); 16 patients had intact chordae tendineae (chronic MR, group 2). No difference was found between groups 1 and 2 with regard to hemodynamic findings. Left atrial volumes in end systole (LAESV) and end diastole (LAEDV) were determined by 2DE from apical four- and two-chamber views with the use of a biplane area-length method and a light pen system. The LAESV and LAEDV measured 116 +/- 66 ml and 56 +/- 48 ml, respectively, in group 1, as compared with 185 +/- 101 ml and 105 +/- 62 ml in group 2 (p less than 0.025). Ten patients from group 1 with LAESV less than or equal to 100 ml (group 1A) were compared to the remaining 13 patients with LAESV greater than 100 ml (group 1B). Patients in group 1A had significantly smaller left ventricular volume and higher mean pulmonary wedge pressure, pulmonary artery, and left ventricular end-diastolic pressure compared to patients in groups 1B and 2 (p less than 0.05). Thus, a subset group of patients with flail mitral leaflets and smaller LAESV has hemodynamic features of acute MR, whereas the remainder with larger LAESV are indistinguishable from patients with chronic MR.

Adult↗
PubMed1991

Effect of severe pulmonary hypertension on the calculation of mitral valve area in patients with mitral stenosis.

We studied 50 consecutive patients with mitral valve stenosis (MS) by cardiac catheterization and Doppler echocardiography to assess whether the presence of severe pulmonary hypertension affected the calculation of valve area by Doppler pressure half-time method and by the Gorlin formula using pulmonary capillary wedge pressure as an index of left atrial pressure. Patients with severe mitral regurgitation were excluded. In patients with pulmonary artery systolic pressure (PAS) less than 70 mm Hg (n = 33), there was good correlation between the mitral valve area derived from Doppler echocardiography and from cardiac catheterization (r = 0.85). However, in patients with PAS greater than or equal to 70 mm Hg (n = 17), this correlation was not as good (r = 0.57). In these 17 patients, the Gorlin formula tended to underestimate the valve orifice area (mean valve area 0.85 +/- 0.49 and 1.06 +/- 0.46 cm2 by catheterization and by Doppler respectively, p = NS). Direct measurement of the valve area by two-dimensional echocardiography was possible in 12 of the 17 patients and correlated well with Doppler values (r = 0.91). Hence in the presence of severe pulmonary hypertension, Doppler pressure half-time estimation of mitral valve area is more accurate than is catheterization-derived valve area, using the wedge pressure and the Gorlin formula.

Acute Disease↗
PubMed1994

The effects of complete versus incomplete mitral valve repair in experimental mitral regurgitation.

Severe mitral regurgitation (regurgitant fraction 0.75 +/- 0.02) was created in eight dogs by our closed-chest chordal rupture technique. After 3 months of chronic mitral regurgitation all indices of contractile function were depressed. Mitral valve repair was then attempted. Postoperative regurgitant fraction was reduced compared with the preoperative value in all eight dogs. Concomitantly, forward cardiac output increased in all dogs and pulmonary capillary wedge pressure fell in all dogs. However, in some dogs, significant regurgitation persisted despite repair. Postoperative regurgitant fraction ranged from 0% to 60%. Postoperative residual regurgitant fraction was related significantly to postoperative cardiac output (r = 0.99), pulmonary capillary wedge pressure (r = 0.77), ejection fraction (r = 0.75), and two indices of contractile function--the mass-corrected end-systolic stress volume relationship (r = 0.87) and end-systolic stiffness (r = 0.93). In general, these parameters returned to their normal values before mitral regurgitation when postoperative regurgitant fraction was less than 30%. Myocytes isolated from the ventricles at the end of study also demonstrated normal contractile function when regurgitant fraction was less than 30%.

Animals↗
PubMed1998

Papillary muscle shortening for mitral valve reconstruction in patients with ischaemic mitral insufficiency.

AIMS: To evaluate the feasibility of papillary muscle shortening in a specific group of high risk patients with ischaemic mitral regurgitation undergoing mitral valve reconstruction. BACKGROUND: From January 1996 to December 1997, 712 (10.1%) out of a total of 7042 open heart patients underwent mitral valve surgery in our hospital. Mitral valve reconstruction was performed in 408 of these patients (57.3%) and valve replacement had to be performed in 304 patients (42.7%). METHODS: A specific technique of papillary muscle reconstruction was performed in 32 patients undergoing valve reconstruction (7.8%). These cases had degenerated and had developed fibrotic elongated papillary muscles, which resulted in prolapses of one or more parts of the mitral valve leaflets. The aetiology in this group of patients was ischaemic, requiring concomitant myocardial revascularization in 28 patients (87.5%) with a mean of 2.7 grafts/patient. All patients underwent papillary muscle shortening using a pericardium pledget-reinforced Polytetrafluoroethylene suture and annuloplasty with a Carpentier-Edwards Physio Annuloplasty Ring. Of these 32 patients, 17 (53.1%) were male, the mean age was 67.1+/-9.7 years (range 41 to 81 years) and all but one were in pre-operative NYHA class III or IV. RESULTS: There were two hospital deaths (6.2%). Postoperative Doppler echocardiography indicated satisfactory mitral valve function in all patients. Within the short mean follow-up period of 9.6+/-5.4 months (3 to 26 months) there was one non-cardiac-related death (3.1%). There was no need for reoperation, and no cases of thromboembolic and bleeding complications in the postoperative period. All patients were in NYHA functional class I or II at the time of follow-up. CONCLUSION: Our results indicate that mitral valve repair is a safe treatment for this group of high risk patients, and that papillary muscle shortening is a valuable tool in these patients with ischaemic mitral regurgitation undergoing surgery.

Adult↗
PubMed1999

[Valve replacement for congenital mitral stenosis associated with double orifice mitral valve: a case report and a review of Japanese literatures].

A 3-year-old girl with congenital mitral stenosis (CMS) associated with double mitral orifice valve (DOMV) underwent successfully mitral valve replacement (MVR). DOMV is a rare form of congenital cardiovascular anomaly. To our knowledge, our patient is the first infant case of CMS due to DOMV in Japan. We present an infant case of CMS associated with DOMV who needed MVR, and discuss our patient with a review of Japanese literatures.

Cardiac Surgical Procedures↗
PubMed1997

Accurate assessment of mitral valve area in patients with mitral stenosis by three-dimensional echocardiography.

The accuracy of measurements of mitral valve orifice area (MVA) from three-dimensional echocardiographic (3DE) image data sets obtained by a transthoracic or transesophageal rotational imaging probe was studied in 15 patients with native mitral stenosis. The smallest MVA was identified from a set of eight parallel short-axis cut planes of the mitral valve between the anulus and the tips of leaflets (paraplane echocardiography) and measured by planimetry. In addition, MVA was measured from the two-dimensional short-axis view (2DE). Values of MVA measured by 3DE and 2DE were compared with those calculated from Doppler pressure half-time (PHT) as a gold standard. Observer variabilities were studied for 3DE. MVA measured from PHT ranged between 0.55 and 3.19 cm2 (mean +/- SD 1.57 +/- 0.73 cm2), from 3DE between 0.83 and 3.23 cm2 (mean +/- SD 1.55 +/- 0.67 cm2), and from 2DE between 1.27 and 4.08 cm2 (mean +/- SD 1.9 +/- 0.7 cm2). The variability of intraobserver and interobserver measurements for 3DE measurements was not significantly different (p = 0.79 and p = 0.68, respectively); for interobserver variability, standard error of the estimate = 0.25. There was excellent correlation, close limits of agreement (mean difference +/- 2 SD), and nonsignificant differences between 3DE and PHT for MVA measurements (r = 0.98 [0.02 +/- 0.3] and p = 0.6), respectively. There was moderate correlation, wider limits of agreement, and significant difference between 2DE and PHT for MVA measurements (r = 0.89 [0.32 +/- 0.66] and p = 0.002), respectively. This may be related to the difficulties in visualization of the smallest orifice in precordial short-axis views. This study suggests that three-dimensional image data sets, by providing the possibility of "computer slicing" to generate equidistant parallel cross sections of the mitral valve independently from physically dictated ultrasonic windows, allow accurate and reproducible measurement of the MVA.

Adult↗
PubMed2004

Does chronic mitral regurgitation influence Doppler pressure half-time-derived calculation of the mitral valve area in patients with mitral stenosis?

BACKGROUND: In patients with mitral stenosis (MS), Doppler pressure half-time (PHT) may be influenced by hemodynamic variables other than the anatomic mitral valve orifice narrowing. This study was undertaken to assess whether the presence of concomitant mitral regurgitation (MR) affects mitral valve area (MVA) estimation by PHT. METHODS: Consecutive patients (n = 166) with noncalcific MS, in sinus rhythm, were studied. Group 1 (n = 106) had no or mild MR, and group 2 (n = 60) had moderate or severe MR. MVA was assessed by using the PHT method and planimetry. RESULTS: There was a strong correlation between planimetry and PHT MVA in both groups (group 1: r = 0.86, P <.001; group 2: r = 0.73, P <.001). However, compared with planimetry MVA, PHT underestimated MVA by > or =20% in 18 patients (17%) in group 1 and 21 patients (35%) in group 2 (P <.01). Overestimation by > or =20% occurred in 12 patients (11%) in group 1 and in 7 (12%) in group 2. Group 2 subanalysis (group 2A: moderate MR, n = 16; group 2B: severe MR, n = 44) revealed that linear regression weakened with increasing severity of MR (group 2A: r = 0.824, P <.001, group 2B: r = 0.70, P <.001). PHT underestimation of MVA occurred in 31% and 36% of patients in Groups IIA and IIB, respectively (P = NS). CONCLUSIONS: PHT appears to be reliable for estimating MVA in most patients with MS, even in the presence of MR. However, the presence of significant MR reduces the reliability of PHT-derived MVA, with underestimation of MVA in a significant number of subjects. The severity of MR has a direct impact on PHT-derived MVA.

Adolescent↗