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Valve-related events and valve-related mortality in 340 mitral valve repairs. A late phase follow-up study.

To assess the early and late valve-related events, 340 consecutive patients undergoing mitral valve repair from 1969 to 1988 were evaluated. Follow-up was complete, with a mean of 7.5% years and range from 2 to 22 years (cumulative 2456 patient-years). There were 221 (65%) female patients. Rheumatic valvular disease was present in 246 (68%) patients. The remaining patients had ischemic or congenital valve disease, floppy valve or infective endocarditis. At surgery, 47% of the patients had pure mitral incompetence, 43% had mixed mitral stenosis and incompetence and 10% had predominant mitral stenosis. Seventy-three percent of the patients were in functional class III or IV. Twelve percent had had prior heart surgery. Concomitant valve procedures including coronary revascularization were performed in 62.3%. There were 23 hospital deaths (6.8%) but only 3 of these (0.8%) were valve-related in patients who died at reoperation for valve repair failure. There were 4 other early repair failures who survived early reoperation. Of the 317 hospital survivors, there were 127 late deaths, and an actuarial survival of 44 +/- 3.7% (70% CL) at 14 years. Of these, 13 were valve-related or 0.5% patient-year. Late events included thromboembolism (TE) 1% patient-year, anticoagulant bleeding 0.4% patient-year, infective endocarditis (IE) 0.2% patient-year and late reoperation for mitral valve repair failure in 63 patients or 2.8% patient-year. At the late follow-up, 88% of the hospital survivors were in functional class I or II.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

Ball-valve thrombus obstructing a bioprosthetic mitral valve.

We present a patient with a large, left atrial ball valve thrombus that was intermittently obstructing a bioprosthetic mitral valve. The diagnosis was confirmed by transesophageal two-dimensional echocardiogram. The transthoracic study initially had failed to demonstrate the true ball valve nature of the thrombus and instead, suggested two separate mass lesions, one in the left atrium and one in the bioprosthetic mitral valve.

Aged↗

Efficacy of mitral valve replacement for patients with mitral regurgitation and a dilated left ventricle.

Mitral regurgitation is a significant complication of end-stage cardiomyopathy, and its existence predicts poor survival. In general, it is thought that mitral valve replacement (MVR) alone is ineffective; however, there are few detailed reports of the clinical course of patients who have undergone MVR. Five patients with mitral regurgitation whose preoperative left ventricular end-systolic volume index was more than 100 ml/m2 were studied. Although their prognosis late after MVR became poor, none of them died within 30 days of the operation. Postoperative cardiac catheterization was performed 6.3+/-1.1 months after surgery; the end-diastolic volume had reduced (before: 193+/-26 ml/m2; after: 166+/-34 ml/m2, p<0.05), but the end-systolic volume had not (before: 110+/-7 ml/m2; after: 112+/-32 ml/m2). The end-systolic wall stress was substantially elevated preoperatively (238+/-29 kdyne/cm2) and tended to increase after surgery (295+/-96 kdyne/cm2). All the patients were able to return to work at some stage postoperatively (their New York Heart Association functional class improved to I or II), but 3 of the 5 patients died suddenly of heart failure at 3.3+/-1.6 years after surgery and the New York Heart Association functional class of the others worsened to III again. Mitral valve surgery, including MVR, can manage severe end-stage heart disease with mitral regurgitation.

Adult↗

Detachment of the mitral valve anterior leaflet as a complication of aortic valve replacement.

Mitral regurgitation after aortic valve replacement is generally reported as a complication of a Manouguian's procedure for annulus enlargement. However, even if no annular enlargement procedure is performed, this complication may be encountered after isolated aortic valve replacement because of either extensive decalcification of the aortic annulus or progressive tension on the anterior leaflet of the mitral valve, caused by aortic valve sutures placed adjacent to firm or heavily calcified valve tissue. Routine transthoracic echocardiography may be inadequate for diagnosis of this condition; transesophageal echocardiography should be used both for preoperative diagnosis and for intraoperative management. We report the case of a patient who had severe mitral regurgitation that occurred after aortic valve replacement with a mechanical valve.

Aortic Valve↗

Late (>or=6 years) results of combined coronary artery bypass grafting and mitral valve replacement for severe mitral regurgitation secondary to acute myocardial infarction.

Analysis of outcomes in 31 patients who had combined mitral valve replacement (MVR) and coronary artery bypass grafting (CABG) for ischemic mitral regurgitation (MR) disclosed that 12 patients had MR because of papillary muscle rupture and that 19 patients had MR because of papillary muscle necrosis or fibrosis without rupture. Of the 12 patients with rupture, 6 died within 2 months of operation and the other 6 lived >or=6 years postoperatively; of the 19 patients without rupture, none died within 2 months of operation and 11 (58%) lived at least 6 years.

Aged↗

Early and late results of mitral valve repair in children.

Mitral valve repair in children has the advantage of avoiding mitral valve replacement with its attendant need for anticoagulation and reoperation. Seventy-nine children between the ages of 2 months and 17 years (mean 4.9 years) underwent mitral valve repair between May 1982 and April 1993. There were five patients with mitral stenosis and 74 patients with mitral regurgitation, and 19 children were less than 2 years of age. Patients were divided into anatomic subgroups on the basis of the primary cardiac pathologic condition. Forty-three had severe mitral regurgitation, 21 had moderate mitral regurgitation, and 12 patients with primum atrial-septal defect and 2 patients with univentricular hearts had minimal to moderate mitral regurgitation. Associated cardiac anomalies were present in 68 patients and 85% of the patients required concomitant intracardiac procedures. The methods of mitral valve repair included annuloplasty in 68 (86%), repair of cleft leaflet in 41 (52%), chordal shortening in 9 (11%), triangular leaflet resection in 8 (10%), splitting of papillary muscles with resection of subvalvular apparatus in 7 (9%), and chordal substitution in 1 (1%). The technique of annuloplasty was modified to allow for annular growth. Follow-up was available from 1 to 10 years (mean 4 +/- 2.5 years). There were three early deaths (4%), all occurring as a result of low output cardiac failure in patients with minimal postoperative mitral regurgitation. Three late deaths (4%) occurred in patients with persistent moderate to severe mitral regurgitation and progressive cardiac failure and eight patients (10%) required either rerepair or replacement of the mitral valve. Actuarial survival was 94% at 1 year, 84% at 2 years, and 82% at 5 years, and actuarial freedom from reoperation was 89% at 8 years. All patients received postoperative echocardiography with 82% having minimal to no mitral regurgitation and 98% of long-term surviving patients being free of symptoms. We conclude that mitral valve repair can be done with low early and late mortality. The need for reoperation is relatively low and valve growth has occurred with the use of a modified annuloplasty.

Actuarial Analysis↗

Fourier phase analysis of SPECT equilibrium radionuclide angiography in symptomatic patients with mitral valve prolapse without significant mitral regurgitation: assessment of biventricular functional abnormalities suggesting a cardiomyopathy.

BACKGROUND: Ventricular premature beats are common in patients with mitral valve prolapse (MVP). The purpose of this study was to determine whether symptomatic patients with MVP had certain functional characteristics and if ventricular arrhythmia (VA) could be explained by functional extravalvular abnormalities. Single photon emission computed tomography equilibrium radionuclide angiography with Fourier phase analysis was preferred to the planar radionuclide method. Only patients without significant mitral regurgitation were studied. METHODS AND RESULTS: A total of 23 symptomatic patients with MVP (13 men, 10 women, mean age, 47+/-14 years) without mitral regurgitation underwent single photon emission computed tomography equilibrium radionuclide angiography. Symptoms were present in 20 patients, and VA was present in 14 patients. Ejection fraction, regional wall motion, and Fourier phase analysis were examined in both ventricles and compared with results for normal subjects. Ventricular abnormalities were observed in 20 (87%) patients: decreased left ventricular and right ventricular ejection fractions, increased standard deviations of the mean phase and focal wall motion, and/or delayed phase abnormalities. Abnormalities were less frequent but more marked in the right ventricular free wall, the infundibulum, or the septum compared with left ventricular delayed abnormalities, which were more frequent but limited. In 12 of 14 patients with VA, phase-delayed areas were observed in the ventricle where the origin of ventricular premature beats was suspected on the basis of their electrocardiographic morphologic features. A relation was found between late potentials and delayed-phase areas (right ventricle or septum) and left bundle branch block morphologic features of VA. CONCLUSIONS: Symptomatic patients with MVP frequently have ventricular dysfunction in 1 or both ventricles, sometimes limited but more marked in the presence of severe VA even without significant mitral regurgitation, suggesting structural modification. The use of a sensitive, accurate, and 3-dimensional method such as single photon emission computed tomography equilibrium radionuclide angiography may be of interest for a noninvasive investigation, especially in young symptomatic patients with MVP and VA.

Arrhythmias, Cardiac↗

[Is this mitral valve prolapse? A case of mitral regurgitation with early systolic murmur due to early systolic prolapse of the posterior leaflet].

This paper reports the findings of phonocardiograms, echocardiogram and Doppler echocardiograms in a case of a 50-year-old man with early mitral valve prolapse with an early systolic murmur. A characteristic early systolic crescendo murmur was recorded at the apex. By amyl nitrite inhalation, the early systolic murmur was attenuated and a late systolic murmur was evoked. On the contrary, methoxamine injection increased the intensity of the early systolic murmur. Early systolic prolapse and early systolic buckling were recorded by two-dimensional and M-mode echocardiography. The phase of mitral regurgitation detected by M-mode color Dopper echocardiography coincided well in timing with the early systolic murmur and the early systolic buckling recorded on the M-mode echocardiogram. A discussion was made on the mechanism of the early systolic mitral regurgitation due to early mitral valve prolapse.

Amyl Nitrite↗

Hemodynamic performance of an unstented xenograft mitral valve substitute.

OBJECTIVE: Stentless mitral xenografts offer potential clinical benefits because they mimic the normal bileaflet mitral valve. How best to implant them and their hemodynamic performance and durability, however, remain unknown. METHODS: A stentless porcine mitral xenograft valve (Medtronic physiologic mitral valve) was implanted in 7 sheep with papillary muscle sewing tubes attached with transmural left ventricular sutures. Radiopaque markers were inserted on the leaflets, annular cuff, papillary tips, and left ventricle. After 10 +/- 5 days, the animals were studied with biplane videofluoroscopy to determine 3-dimensional marker coordinates at baseline and during dobutamine infusion. Transesophageal echocardiography assessed mitral regurgitation and valvular gradients. Mitral annular area was calculated from the annular markers. Physiologic mitral valve leaflet and annular dynamics were compared with 8 native sheep valves. RESULTS: Average mitral regurgitation grade at baseline was 1.2 +/- 1.0 (range, 0-4), and the mean transvalvular pressure gradients were 3.6 +/- 1.3 and 6.2 +/- 2.2 mm Hg during baseline and dobutamine infusion, respectively. Xenograft mitral annular area contraction throughout the cardiac cycle was reduced (6% +/- 6% vs 13% +/- 4% for physiologic mitral valve and control valve, respectively; P =.03). Physiologic mitral valve leaflet geometry during closure differed from the native valve, with the anterior leaflet being convex to the atrium and with little motion of the posterior leaflet. Three animals survived more than 3 months; good healing of the annular cuff and papillary muscle tubes was demonstrated. CONCLUSION: This stentless xenograft mitral valve substitute had low gradients at baseline and during stress conditions early postoperatively, with mild mitral regurgitation. Preliminary analysis of healing characteristics appeared favorable at 3 months. Additional studies are needed to determine long-term xenograft mitral valve performance and resistance to calcification.

Animals↗

Relationship between resting parameters of the mitral valve and exercise capacity in patients with mitral stenosis: can the diastolic filling period predict exercise capacity?

BACKGROUND AND AIMS OF THE STUDY: In order to provide patients with better exercise capacity, interventional therapy to the mitral valve is often carried out in mitral stenosis (MS). Hence, it is crucial to determine exercise capacity before deciding on the time of intervention. The study aim was to demonstrate whether resting parameters of the mitral valve, notably left ventricular diastolic filling period (LVDFP) and mitral valve resistance (MVR), relate to restricted exercise capacity. METHODS: Forty-six patients (30 females, 16 males; mean age 44+/-11 years; range: 33-55 years) with rheumatic MS were enrolled. Exercise capacities of patients were grouped according to NYHA classification and maximal exercise tolerance values obtained using exercise testing. Exercise capacity in male patients was quantified. Relationships between patient variables and exercise capacity were evaluated using simple linear regression analysis. In order to identify determinants of exercise capacity, a discriminate multivariate analysis was performed with variables, which were found to correlate significantly in the univariate analysis. RESULTS: There were no correlations between echo score, MVR, planimetric mitral valve area (MVA), MVA obtained by the pressure half-time method or calculated by the continuity equation, and transmitral mean gradient and exercise capacity classes as defined by both NYHA and exercise testing. The only predictor of exercise capacity class determined by discriminate multivariate analysis using the significant parameters in the linear regression analysis was LVDFP. The quantified exercise capacity in male patients correlated only with LVDFP (r = 0.64, p = 0.008). CONCLUSION: Exercise capacity cannot be predicted using routine resting parameters of the mitral valve (including MVR) in patients with MS. In this respect, the LVDFP may be of value.

Adult↗

Percutaneous treatment of valvular heart disease: catheter-based aortic valve replacement and mitral valve repair therapies.

Until recently, percutaneous catheter therapy for valvular heart disease was limited to catheter balloon valvuloplasty for aortic, mitral, or pulmonic stenosis. A number of new approaches to percutaneous valve therapy are now developing rapidly, including methods for catheter-based valve replacement and repair. Stent-mounted valve prostheses have been successfully implanted in the pulmonic and aortic positions. These devices have been constructed using pericardial valve leaflets mounted inside balloon-expandable or self-expanding stents and have been used in patients who are high risk for valve replacement surgery. Percutaneous valve repair is also being developed for mitral regurgitation. Direct leaflet repair and percutaneous annuloplasty are being employed in clinical trials. All the percutaneous approaches are based on existing surgical techniques and offer less invasive alternatives. The era of percutaneous valve therapy has clearly arrived, and ongoing trials will define the clinical role for these new therapies.

Aortic Valve↗

Cardiac valve orifice equation independent of valvular flow intervals: application to mitral valve area computation in mitral stenosis and comparison with the Gorlin formula and direct anatomical measurements.

An orifice equation is developed which relates the effective mitral valve area (A), the average mitral valve pressure gradient (dP), the cardiac output (Q) and the heart frequency (f) through considerations of momentum conservation across the mitral valve. The form of the new equation is A = (4.75 X 10(-5)Qf/dP, where A, Q, and dP are expressed in cm2, ml X min-1 and mmHg respectively. Mitral valve areas computed with the new orifice formula are found to correlate with those computed by the Gorlin formula in conditions of equilibrium associated with the resting state at a level of r = 0.95, SE = 0.15 cm2, with autopsy measurements at a level of r = 0.85, SE = 0.18 cm2 and with direct anatomical measurements of excised valves at a level of r = 0.78, SE = 0.41 cm2. The results suggest that the new formula may be considered as an independent orifice equation enjoying a similar domain of validity as the Gorlin formula. The new equation offers the possibility of deriving additional useful haemodynamic relationships when used in combination with established cardiological formulas.

Hemodynamics↗