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PubMed2004

Ischemic mitral valve prolapse: mechanisms and implications for valve repair.

OBJECTIVE: The aim of this study was to assess the mechanisms of prolapse in ischemic mitral valve regurgitation (MR) and the techniques of valve repair. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Aged↗
PubMed1998

Blood rheology in patients with native heart valve disease and after valve replacement.

Patients with heart valve disease have rheologic abnormalities that are more pronounced in double valve disease than in mitral or aortic valve disease; after valve replacement surgery, the degree of rheologic abnormality is more pronounced in patients with mechanical and biological prostheses than in those with homografts and pulmonary autografts. Rheologic abnormalities seen in these patients might be related to the different incidences of thromboembolism in the presence of various valve defects and various types of prostheses.

Adolescent↗
PubMed1998

Predictors of left atrial thrombus and spontaneous echo contrast in rheumatic valve disease before and after mitral valve replacement.

In this study we aimed to analyze, with reference to mitral regurgitation (MR), the incidence and predictors of left atrial (LA) thrombus and spontaneous echo contrast in patients with rheumatic valve disease before and after mitral valve replacement. The incidence of LA thrombus is known to be less in patients with MR. The impact of mitral valve replacement on this beneficial effect has not been studied in detail. The study included 169 consecutive patients (59 men and 110 women, average age 40 +/- 13 years) with rheumatic mitral valve disease who underwent transesophageal echocardiographic examination 1 to 3 days before and within 7 days (mean 4.0 +/- 1.3) after mitral valve replacement using mechanical prostheses in a single institution. The preoperative incidence of echocardiographic LA spontaneous echo contrast (SEC) was 1.1%, 30%, and 54%, and the incidence of thrombus was 1.1%, 13%, and 17% in the groups with MR, combined mitral stenosis + MR, and isolated mitral stenosis, respectively. In the MR group, SEC and thrombus incidence increased significantly after surgery. The independent predictors for postoperative thrombus development were atrial fibrillation, postoperative SEC, and preoperative thrombus. Thrombus recurred after surgery in 64% of 14 patients who had surgical thrombectomy. The presence of postoperative MR was associated with decreased risk of postoperative SEC and thrombus development. The interaction between MR and SEC and thrombus both before and after surgery provides further support for the protective effect of MR against LA thrombus formation.

Adult↗
PubMed1988

Marfan's syndrome: combined composite valve graft replacement of the aortic root and transaortic mitral valve replacement.

Echocardiographic studies in patients with Marfan's syndrome indicate that 95% eventually have aortic root dilatation, mitral valve prolapse, or a combination of these. Both lesions can progress and require operation for aortic root aneurysm, aortic valve insufficiency, and mitral valve insufficiency. This report reviews the simplified treatment of 6 patients by combined composite valve graft replacement of the aortic root and transaortic mitral valve replacement at one operation. All patients survived and are well for periods extending from 1 month to 12 months.

Adult↗
PubMed1988

Retraction of bioprosthetic heart valve cusps: a cause of wide-open regurgitation in right-sided heart valves.

Most failures of bioprosthetic heart valves in children are due to stenosis secondary to thrombus, calcific deposits, or tissue ingrowth. Valve failures due to regurgitation typically involve cuspal detachment, tears, or perforations. We present four cases of prosthetic valve regurgitation in children caused by cuspal retraction without stenosis and describe the morphologic findings related to the valves at autopsy or explantation. A mononuclear cell and giant cell response to the cusps of the valve was a striking finding in one patient.

Adolescent↗
PubMed2001

Left ventricular architecture after valve replacement due to critical aortic stenosis: an approach to dis-/qualify the myth of valve prosthesis-patient mismatch?

OBJECTIVES: Left ventricular hypertrophy in patients with critical aortic stenosis (AS) is an adaptive process that compensates for high intracavitary pressure and reduces systolic wall stress followed by an increase in myocardial masses. In the present prospective clinical trial, we investigated long-term compensatory changes in left ventricular geometry and function after aortic valve replacement using mechanical bileaflet prostheses with the main emphasis on the small-sized aortic annulus and valve prosthesis-patient mismatch. METHODS: A total of 58 patients with critical AS were assigned to the following groups according to the predictive value of prosthetic valve area index (VAI): group EXMIS: 29 patients (VAI < or =0.99), expected mismatch; group NOMIS: 29 patients (VAI < or =0.99), no mismatch. At controls T(0) (before operation/operation (OP), T(1) and T(2) (4 and 20 months after OP) the left ventricular geometry was recorded by means of Imatron electron beam tomography and the transprosthetic velocities were measured by echocardiography. RESULTS: Statistical analysis showed a consistent reduction in the absolute (P=0.04) and indexed (P=0.04) left ventricular myocardial mass for both cohorts; furthermore, there was a significant difference between EXMIS and NOMIS patients concerning the factors, time and mass reduction (P=0.005), because of distinct baselines. A logistic regression report revealed preoperative cardiac output, absolute left ventricular myocardial mass, perfusion, body surface area and the native valve orifice area as predicting coefficients and factors for a minimum mass reduction of 25%. We explain a mathematical formula that turned out to be the most sensitive for correctly classified factors. CONCLUSIONS: The left ventricular geometry and transprosthetic velocities resulted in the same postoperative recovery for both EXMIS and NOMIS patients. The presented data showed that valve prosthesis-patient mismatch had no influence in several stepwise logistic regression models. We conclude that modern mechanical bileaflet prostheses allow both acceptable hemodynamics and recovery of left ventricular hypertrophy, even in small aortic annuli.

Aged↗
PubMed1990

Combined mitral and aortic valve replacement with Bjørk-Shiley prostheses: long term survival and valve-related complications.

Between 1974 and 1985, combined aortic and mitral valve replacement (DVR) was performed in 209 patients using Bjørk-Shiley tilting-disc prostheses. Early and late mortality were 9.5% and 10.5% respectively for the entire series. Factors significantly influencing early mortality were: Emergency DVR, preoperative NYHA Class IV, double valve, critical stenosis, and small aortic replacement prostheses. The effect of the latter was augmented by the suboptimal orientation of the implanted prostheses. The overall survival was 74 +/- 4.4% at 12 years; but was only 40 +/- 6.1% at 8 years in patients who were in NYHA class IV preoperatively. Intermittent disc occlusion (DO) and thrombotic disc occlusion (TO), presented as early, anticoagulant related haemorrhage (AH) and prosthetic valve endocarditis (ENDO) as sporadic, and thromboembolism (TE) and paravalvular leak (PVL) as continuous risk factors. Freedom from all known valve-related complications was 77 +/- 4.5% at 12 years (DO, TO, AH, ENDO, TE, PVL: 98%, 97%, 96%, 96%, 88% and 89% respectively). Lethal DO and TO occurred in mitral prostheses. Freedom from reoperation was 95% at 5 and 12 years. Patient-related valve failure rate in this series is comparable with the other series which used mechanical prostheses and is lower than those which used bioprostheses.

Adult↗
PubMed1986

Eleven year experience of aortic valve replacement with antibiotic sterilized homograft valves in Southampton.

Aortic valve replacement with an antibiotic-treated aortic valve homograft was performed in 200 patients between April 1973 and December 1984. In all cases, a two-layered freehand technique of valve implantation was used. Tailoring of the annulus was performed in 39 cases and a gusset in the non-coronary sinus was used to maintain the shape of the aortic root in 67 patients. There were 6 early deaths (3%) and 14 late deaths (7.2%); 4 of these were related to homograft regurgitation. The 11 years survival rate on actuarial analysis was 83%. The overall incidence of early diastolic murmurs was 27.3%; being significantly higher in those with tailored roots (P less than 0.001). Severe homograft aortic valve incompetence requiring re-operation developed in 3.1%. Anticoagulant therapy was not used routinely, and there was no major thromboembolic episode in those who had isolated homograft aortic valve replacement. There was one case of miliary tuberculosis but pyogenic and fungal endocarditis were not encountered. No hemolysis, valvular calcification or stenosis was observed.

Adolescent↗
PubMed1990

Long-term performance of Starr-Edwards silastic ball valves and St Jude Medical bi-leaflet valves. A comparative analysis of implantations during 1980-86 for aortic stenosis.

Long-term performance of Starr-Edwards silastic ball (SESB, n = 168) and St Jude Medical bi-leaflet (SJMB, n = 93) valves in patients who were alive 30 days after implantation (1980-86) for aortic stenosis was compared. Mean follow-up was 3.0 years (0.1-7.9 years). The SESB and SJMB groups differed as regards female gender (18% vs 47%, P less than 0.0001), NYHA classes III-IV (59% vs 72%, P less than 0.05), coronary artery disease (CAD, 32% vs 62%, P less than 0.01) in patients with coronary arteriography (n = 82 and n = 55, respectively), and prosthetic annulus diameter (26 +/- 1 vs 23 +/- 2 mm, P less than 0.0001). Five-year survival +/- SE in SESB vs SJMB patients was: total population, 89 +/- 3% vs 80 +/- 6% (NS); coronary arteriography population, no CAD, 90 +/- 4% vs 100% (NS), and with CAD, 71 +/- 11% vs 60 +/- 13% (NS; P = 0.01 for CAD). Five-year event-free survival +/- SE in SESB vs SJMB patients was 95 +/- 2% vs 97 +/- 2% (NS) for thromboembolism, 95 +/- 2% vs 89 +/- 4% (NS) for coumadin-related haemorrhage, 98 +/- 1% vs 99 +/- 1% (NS) for endocarditis, 98 +/- 1% vs 94 +/- 5% (NS) for paravalvular leak, 88 +/- 3% vs 79 +/- 6% (NS) for all valve-related complications, and 98 +/- 1% vs 95 +/- 4% (NS) for prosthesis replacement. Thrombotic occlusion or structural failure were not observed. No patients without CAD experienced thromboembolic events. Cox regression analyses (in both total population and coronary arteriography population) of survival as well as the various complications revealed that the type of prosthesis did not have predictive influence. CAD was an independent risk factor for thromboembolism, haemorrhage, and all valve-related complications. Previous systemic hypertension was independently predictive of haemorrhage. The SESB and SJMB prostheses showed comparable and acceptable long-term performance. Only patient-related variables, notably CAD, influenced late results. The proven durability and relatively low price of the SESB valves together with the excellent haemodynamic performance of even small-sized SJMB valves should be considered in the light of the present results.

Adolescent↗
PubMedDate not supplied

Evaluation of the mitral valve leaflet morphology after mitral valve reconstruction with a concept "coaptation length index".

BACKGROUND: In clinical settings, information on morphology of mitral valve leaflet after mitral valve reconstruction is limited. METHODS: Between January 1996 and June 2000, 36 underwent mitral valve repair for mitral regurgitation (MR). The etiology of mitral insufficiency was prolapse, dilated annulus, and ischemic. Ring annuloplasty was performed in all cases. Mitral valve short-axis dimension (MVd), vertical distance between annular line and closing point (Vd), coaptation length (CL), coaptation length index (CL/MVd) were measured by the two-dimensional transesophageal echocardiography for the present 11 cases. RESULTS: In 11 cases, residual MR, using a scale from 0 to 4, was 0 in 5 patients, 1 in 4 patients, 2 in 2 patients whose etiology of regurgitation was cardiomyopathy. MVd and Vd decreased significantly (38.7 +/- 6.2 to 27.0 +/- 5.6 mm, 10.1 +/- 7.7 to 6.5 +/- 4.6 mm, respectively). CL and CLI increased significantly (6.4 +/- 2.4 to 11.6 +/- 4.6 mm, 0.16 +/- 0.06 to 0.44 +/- 0.21, respectively). Among those index, only CLI have a statistically significant negative correlation with the degree of residual MR. CONCLUSION: The mitral valve ring annuloplasty produce the morphologic change of mitral apparatus, especially the increase of CLI, which may be one of the main factors in regulation of regurgitation.

Adult↗
PubMed1975

The floppy mitral valve syndrome--a review of fourteen patients requiring valve surgery.

The correlation of clinical features with the operative findings in 14 patients with a floppy mitral valve is discussed. The clinical course is typified by rapidly progressive disability. An abrupt deterioration was present in five of our subjects and this may be due to rupture of chordae tendinea or stretching of the valve apparatus. The redundancy of the anterior cusp in 13 of our series may explain the absence of mid systolic clicks in all except one patient. The diagnosis of prolapse can be difficult to make prior to surgery because the prolapsed cusp may be masked by the regurgitant contrast medium. Hypokinesis and prominent inflow sacculation of the left ventricular inflow tract suggest an associated myocardial abnormality. Calcium was present in one valve and thus mitral valve calcification does not exclude the possibility of a floppy valve in patients with mitral regurgitation.

Adolescent↗
PubMedDate not supplied

Evaluation of the mitral valve leaflet morphology after mitral valve reconstruction with a concept "coaptation length index".

BACKGROUND: In clinical settings, information on morphology of mitral valve leaflet after mitral valve reconstruction is limited. METHODS: Between January 1996 and June 2000, 36 patients underwent mitral valve repair for mitral regurgitation (MR). The etiology of mitral insufficiency was prolapse, dilated annulus, and ischemia. Ring annuloplasty was performed in all cases. Mitral valve short-axis dimension (MVd), vertical distance between annular line and closing point (Vd), coaptation length (CL), and coaptation length index (CLI) were measured by two-dimensional transesophageal echocardiography for the present 11 cases. RESULTS: In 11 cases, residual MR, using a scale from 0 to 4, was 0 in 5 patients, 1 in 4 patients, 2 in 2 patients whose etiology of regurgitation was cardiomyopathy. MVd and Vd decreased significantly (38.7+/- 6.2 to 27.0 +/- 5.6 mm, 10.1 +/- 7.7 to 6.5 +/- 4.6 mm, respectively). CL and CLI increased significantly (6.4 +/- 2.4 to 11.6 +/- 4.6 mm, 0.16 +/- 0.06 to 0.44 +/- 0.21, respectively). Among those indices, only CLI has a statistically significant negative correlation with the degree of residual MR. CONCLUSION: Mitral valve ring annuloplasty produces the morphologic change of the mitral apparatus, especially increase of CLI, which may be one of the main factors in regulation of regurgitation.

Adult↗
PubMed2001

Emergency redo mitral valve replacement in a 27-year-old pregnant female with a clotted prosthetic mitral valve, preoperative fetal demise and postoperative ventricular assist device: a case report.

A 27-year-old Laotian woman with a St Jude mechanical mitral valve became pregnant, requiring a change in her anticoagulant after the first trimester when her warfarin sodium (coumadin) was replaced with enoxaparin sodium (lovenox). Her prosthetic valve clotted and became dysfunctional. She was 16 weeks pregnant and was taken to the operating room for emergency surgery for replacement of the valve. The fetus had not been viable for 1-2 weeks, but still remained in utero. The clotted valve was replaced with another St Jude valve of a slightly smaller diameter (27 mm). The patient could not be weaned from bypass so a right ventricular assist device (RVAD) was inserted. The patient was weaned from the RVAD after 2 days of support. Two days following removal of the RVAD the fetus spontaneously aborted. The patient had a long, complicated hospital course and was discharged 3 months later. She subsequently died 4 months after discharge of a cerebral hemorrhage from excessive anticoagulation.

Adult↗
PubMed1977

Regression of pulmonary hypertension after mitral valve surgery in children. Operative management of rheumatic mitral valve disease.

Forty-one children with advanced chronic rheumatic disease of the mitral valve had preoperative and postoperative hemodynamic studies. Twenty-three cases had open mitral commissurotomy, and 20 had mitral valvular replacement. After surgery the average pulmonary arterial systolic pressure in the group with valve replacement decreased from 78 to 42 mm Hg, the pulmonary vascular resistance decreased from 974 to 313 dynes sec cm 5, and the cardiac index rose from 2.29 to 4.15 L/min sq m. In the group with mitral commissurotomy, the average pulmonary arterial systolic pressure decreased from 90 to 63 mm Hg, the pulmonary vascular resistance decreased from 1,201 to 616 dynes sec cm-5, and the cardiac index rose from 2.5 to 3.5 L/min sq m. While all patients with mitral valve replacement showed a drop in pulmonary arterial pressure, the postoperative pressures were higher after commissurotomy in four patients, two of whom required a second operation of valve replacement. The study shows that in children, even severe degrees of pulmonary hypertension secondary to mitral valve abnormality is corrected.

Adolescent↗
PubMed1997

High incidence of Chlamydia pneumoniae in sclerotic heart valves of patients undergoing aortic valve replacement.

Chlamydia pneumoniae has previously been demonstrated in the atherosclerotic lesions of various arteries, including the coronary arteries, and has been proposed to play a role in the pathogenesis of atherosclerosis. A prospective study of the incidence of C. pneumoniae in the sclerotic valves of patients undergoing aortic valve replacement because of aortic stenosis and in the aortic valves of cases dying of non-cardiac reasons and undergoing forensic autopsy was undertaken. The results were correlated to serological markers of past (IgG) or persistent (IgA) C. pneumoniae infection. C. pneumoniae, as determined by the polymerase chain reaction (PCR), was detected in the aortic valve in 19/39 (49%) patients and in 1/11 (9%) autopsy controls (p = 0.018) and confirmed by electron microscopy in one patient. There was no significant difference in the incidence rate of IgG or IgA antibody positivity between PCR-positive and PCR-negative cardiac patients. These results extend the hypothesis of a pathogenic role of C. pneumoniae in atherosclerosis to include also aortic valve sclerosis.

Adult↗
PubMed1979

Chronic haemolysis following combined mitral and aortic valve replacement. A randomized study between the Björk-Shiley and Lillehei-Kaster disc valve prostheses.

Intravascular haemolysis was studied in a randomized series of 35 patients examined 12--24 months after combined mitral and aortic valve replacements with either the Björk-Shiley (pyrolytic carbon) tilting disc valve (19 patients) or the Lillehei-Kaster pivoting disc valve (16 patients). Red blood cell count, haemoglobin concentrations, and serum bilirubin varied within normal ranges with a few exceptions. Haptoglobin was absent or reduced in 86%, while elevated values for serum lactate dehydrogenase were found in 82%. The increase in serum lactate dehydrogenase activity was moderate and indicated a normal or only slightly reduced red cell lifespan in most patients. Although the intravascular haemolysis was of little clinical significance, the increase in lactate dehydrogenase was significantly higher in patients with the Lillehei-Kaster prosthesis than in patients with the Björk-Shiley prosthesis, indicating a slightly shorter lifespan in the former group. For both models, however, intravascular haemolysis was less severe than previously reported after combined aortic and mitral valve replacement with ball valve prosthesis.

Adult↗
PubMed2001

Determinants of survival after aortic valve replacement as treatment for symptomatic aortic valve disease in the elderly.

BACKGROUND AND AIM OF THE STUDY: The effect of concurrent disease and cardiac comorbidity on survival after bioprosthetic valve replacement in elderly patients was assessed retrospectively. Risk factors were categorized as general, non-cardiac (age, diabetes, previously treated carcinoma) and cardiac (LVEF, three-vessel disease, previous CABG or valve replacement, and endocarditis). METHODS: A total of 400 elderly patients (median age 73 years; range: 71-76 years) was studied. Medical history included diabetes, previous CABG or aortic valve replacement (AVR), endocarditis and treatment of previous carcinoma. A left ventricular ejection fraction (LVEF) of <0.66 and presence of three-vessel disease were also investigated. Hospital deaths (and cause) were recorded; survival or date and cause of death after discharge were obtained by questionnaire. Kaplan-Meier univariate and Cox proportional hazards multivariate regression analyses were carried out. RESULTS: Mortality during follow up was 28.3%; hospital mortality was 3.8%. Univariate analysis showed five factors significantly to affect survival: LVEF, history of endocarditis, carcinoma, age and three-vessel disease. Fifteen of 38 patients with history of carcinoma died, 10 due to a malignancy. Of 76 patients with three-vessel disease, 26 died. A history of diabetes and previous CABG did not influence survival significantly. Four of eight patients with preoperative endocarditis died, all in hospital. Six of 11 patients died after redo-AVR, none before 36 months follow up. By Cox regression analysis, LVEF and histories of carcinoma and endocarditis remained significant. CONCLUSION: AVR should be performed before ventricular deterioration occurs. Previous CABG is not a contraindication for AVR. Endocarditis impaired survival. Long-term mortality after redo-AVR in this population was relatively high, but acceptable. AVR should also be performed in elderly patients with aortic valve disease. Since prognosis of symptomatic aortic valve disease is poor in the short term, AVR is indicated in patients treated for carcinoma.

Aged↗
PubMed2003

Glycosaminoglycan-degrading enzymes in porcine aortic heart valves: implications for bioprosthetic heart valve degeneration.

BACKGROUND AND AIM OF THE STUDY: Glutaraldehyde (GA)-fixed aortic valves used in heart valve replacement surgery have limited durability due to tissue degeneration and calcification. Despite their structural and functional importance, very little is known about the fate of glycosaminoglycans (GAGs) within the extracellular matrix of bioprosthetic heart valves. The study aim was to investigate the stability of GAGs in GA-fixed tissues and to identify enzymatic mechanisms that may be responsible for GAG degeneration. METHODS: Porcine aortic valve cusps were fixed with GA and implanted subdermally in rats for 21 days. Fresh, fixed and explanted cusps were analyzed for GAG content by hexosamine determination, and GAG-degrading enzyme activity was evaluated using zymography. GAG classes in fresh cusps were also assessed by flurorophore-assisted carbohydrate electrophoresis. Fresh and GA-fixed cusps were also exposed in vitro to hyaluronidase and chondroitinase in order to test the susceptibility of cusp GAGs towards enzymatic degradation. RESULTS: Native aortic cusps contained -3.5% GAGs by dry weight, consisting of hyaluronic acid, chondroitin sulfate and dermatan sulfate. Significantly lower GAG levels were found in aortic cusps after fixation with GA, and even lower levels were found after subdermal implantation in rats. GAG levels in GA-fixed cusps were also significantly reduced by in-vitro incubation with hyaluronidase and chondroitinase. Novel GAG-degrading enzymes were detected in considerable levels in native cusps, in lower levels in GA-fixed cusps and significantly increased levels after subdermal implantation of GA-fixed cusps. CONCLUSION: The combined action of active GAG-degrading enzymes and the failure of GA to stabilize GAGs towards enzymatic digestion may contribute significantly to bioprosthetic heart valve degeneration and subsequent structural failure.

Animals↗