Multivalve Disease Research Articles

Conventional Biological versus Sutureless Aortic Valve Prostheses in Combined Aortic and Mitral Valve Replacement.

Sutureless aortic valve prostheses have proven to provide a significant decrease in procedural, cardiopulmonary bypass and cross-clamp time, leading to a significant reduction in mortality risk in elderly high-risk cohorts. In this study, we sought to review our institutional experience on the sutureless aortic valve replacement (SU-AVR) and the concomitant mitral valve replacement (SMVR), comparing the combined conventional surgical aortic valve replacement (SAVR) with SMVR. Between March 2018 and July 2022, 114 consecutive patients underwent a combined aortic and mitral valve replacement at our institution. We stratified the patients according to the operative procedures into two groups and matched them 1:2: Group 1 underwent a combined conventional SAVR and SMVR (n = 46), and Group 2 included combined SU-AVR with Perceval prosthesis and SMVR (n = 23). No significant differences in the preoperative characteristics were present. SU-AVR combined with SMVR demonstrated excellent haemodynamic performance, comparable to that of SAVR plus SMVR, with median postoperative gradients over the aortic valve of 4 mmHg (IQR 3.0-4.0) in Group 1 and 4 mmHg (IQR 3.0-4.0) in Group 2 (p = 0.67). There was no significant difference in the occurrence of postoperative major adverse events such as death, stroke, myocardial infarction and kidney failure between the groups. There was also no significant difference in the permanent pacemaker implantation rate, paravalvular leakage or valve dislocation. We also could not detect any significant difference in postoperative mortality between the groups. SU-AVR has proven to be a reliable alternative to conventional valve prostheses in patients with multivalve disease undergoing combined aortic and mitral valve replacement, offering shorter procedural time and outstanding hemodynamic performance compared to the conventional surgical method.

Contemporary prevalence and outcomes of rheumatic mitral valve surgery.

ObjectiveRheumatic mitral valve disease is often viewed as a historic disease in North America with limited contemporary data. We hypothesized that rheumatic pathology remains common and has worse short‐term outcomes and higher resource utilization compared to other mitral valve pathologies.MethodAll patients undergoing mitral valve repair or replacement (2011–2019) were extracted from a regional Society of Thoracic Surgeons database. Resource utilization metrics included inflation‐adjusted hospital costs. Patients were stratified by mitral valve pathology for univariate analysis.ResultOut of the 6625 mitral valve procedures, 835 (12.6%) were from rheumatic disease, a proportion that incrementally increased over time (+0.39% per year, p = .032). Among 19 hospitals, there was high variability in number of rheumatic mitral operations (median: 22, interquartile range [IQR]: 5–80) and rate of rheumatic repairs (median: 3%, IQR: 0%–6%). Rheumatic patients were younger (62 vs. 65, p < .0001), more often female (75% vs. 43%, p < .001) and with greater burden of heart failure, multi‐valve disease, and lung disease, but less coronary disease. There were no differences in operative mortality (5.2% vs. 5.0%, p = .85) or major morbidity (22.2% vs. 21.8%, p = .83). However, resource utilization was higher for rheumatic patients, including more frequent transfusions (43% vs. 39%, p = .012), longer ICU (73 vs. 64 h, p < .0001) and postoperative length of stay (8 vs. 7 days, p < .0001).ConclusionsRheumatic mitral disease accounts for a meaningful (12%) and rising percentage of mitral valve operations in the region, with high variability among hospitals. Rheumatic mitral surgery yielded similar short‐term outcomes compared to nonrheumatic pathology, but required greater resource utilization.

Impact of mitral annular calcification on hemodynamic effect in mitral stenosis in multiple valve disease: relevant or not

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Prevalence of mitral annulus calcification (MAC) and degenerative mitral stenosis thus elevated transmitral gradient (TMG) is increased with age and multivalve involvement. The management of degenerative multivalve disease is challenging, as is identification of the presence of multivalve involvement and its hemodynamic impact because of interaction between two or more valve lesions especially in degenerative valve disease. Hemodynamic interaction between significant aortic stenosis and mitral annular calcification is often combined with diastolic disfunction which can result in LA enlargement and abnormal atrioventricular coupling and left atrial and ventricular remodeling. Purpose Study aimed to assess the effect of MAC on mitral valve stenosis in patients with multiple valve disease of degenerative origin. Method We retrospectively analyzed 78 patients with elevated transmitral gradient defined as an elevated TMG &amp;gt;4mmHg, MAC in multivalve involvement, mainly degenerative significant aortic valve stenosis who were treated in our clinic from 2018 to 2021. We excluded patients with prior cardiac surgery, congenital heart disease, hypertrophic obstructive cardiomyopathy and with heart rate &amp;gt;100 bpm at time of study and significant mitral regurgitation. Baseline demographic data were extracted from the electronic medical record and echocardiographic data were analyzed from electronic saved data. Results Study identified a total of 78 patients (average age 71,89 years, 64% females). Of 57 analyzed patients 32% patients had severe MAC and calcification of chordae, and 68% patients had MAC and mild or no significant chordae calcification. Patients with aortic gradients, severe aortic stenosis (AVAi 0,80 cm/m2) were observed more often in patients with severe MAC and significant chordae calcification than in those with nonsevere MAC (p &amp;lt; 0.043).There was no significant difference in mitral annular distension between groups. Baseline mean MV gradients were 6,5+-1.5 mm Hg. Mean MVA (continuity equation) was 1,5+-0.4 cm2, and MVAi 0,8+-0,2 cm/m2, mean LA volume 70 ml/m2, mean E/e 35, mean EF LV 68% and mean GLS -14. Conclusion Result suggest that increasing transmitral gradient if superimposed on severe MAC with only modest mitral stenosis will result in a high mean transmitral gradient. The presence of elevated pressure transmitral gradient in patients with more severe aortic stenosis and more severe MAC combined with chordae calcification may imply hemodynamic effect or stress on mitral valve degeneration in multiple valve involvement. Other imaging modalities and further investigation for better understanding effect of hemodynamic stress in multiple valve disease are needed. These observations need to be evaluated on larger cohorts of patients during a longer period of time.

Abstract 17189: Radiation-induced Accelerated Multi-valve Disease In A Patient With Subaortic Membrane

A 69-year-old woman with history of right breast cancer status post lumpectomy and radiation (4.2 cGy) 18 months prior, presented with progressive NYHA class III dyspnea. TTE obtained prior to her cancer diagnosis was notable for normal LV size and wall thickness, a subaortic membrane with systolic mean Doppler gradient of 21 mmHg and a mildly thickened mitral valve without significant stenosis or regurgitation. On presentation, TTE was notable for severely increased concentric LV wall thickness (LV mass index 140 g/m 2 ), preserved ejection fraction, increased RV wall thickness, subaortic stenosis with systolic mean Doppler gradient 35 mmHg, moderate-severe aortic regurgitation, thickened mitral valve with posterior leaflet tethering and anterior leaflet override causing severe mitral regurgitation and moderate mitral stenosis (valve area 1.7 cm 2 by pressure half-time). She underwent a surgical intervention with septal myectomy, subaortic membrane resection, aortic root reconstruction, aortic and mitral valve replacement with bioprostheses. She did well post-operatively and had complete resolution of symptoms following cardiac rehabilitation. Radiation-induced valvular heart disease is linked to the total dose of radiation, use of sequential chemotherapy and time since irradiation, with a typical latency of 10-20 years. However, there is paucity of data regarding the influence of these variables in patients with pre-existing valve disease. This case illustrates dramatic acceleration of underlying aortic and mitral valve pathology in a patient with a subaortic membrane, 18 months after radiation. We also noted development of significant concentric LV hypertrophy that was disproportionate to the degree of obstruction across the sub-aortic membrane. Potential candidates for radiation therapy must be carefully screened for pre-existing valve disease, which should warrant increased vigilance and early screening for progressive valve disease.

Risk Associated With Valvular Regurgitation During Pregnancy

BackgroundPregnancies in women with regurgitant valve lesions are generally considered low risk, but this has not been well studied. ObjectivesThis study determined the frequency of adverse cardiac events (CEs) in pregnant women with moderate or severe regurgitant valve lesions. MethodsMaternal and fetal outcomes in women with moderate or severe chronic valve regurgitation enrolled in a prospective multicenter study on pregnancy outcomes were examined. Adverse CEs included heart failure, sustained arrhythmias, cardiac arrest, or death. A multivariate logistic regression model was used to identify determinants of CEs in women at the highest risk. ResultsOutcomes of 430 pregnancies in women with moderate or severe regurgitant lesions were examined: 145 with mitral regurgitation (MR), 101 with pulmonary regurgitation (PR), 71 with multivalve disease, 73 with tricuspid regurgitation (TR), and 40 with aortic regurgitation (AR). Most women had associated congenital or acquired heart disease. Adverse CEs occurred in 13% of pregnancies: 27% of pregnancies with multivalve disease; 15% with MR; 15% with TR; 5% with AR; and 3% with PR. Maternal mortality was rare. In women with MR, TR, or multivalve disease (n = 289), left ventricular systolic dysfunction (p = 0.001), pulmonary hypertension (p = 0.005), and cardiac events before pregnancy (p < 0.001) were important determinants of CEs during pregnancy. ConclusionsWomen with AR and PR are at low risk for cardiac complications during pregnancy. While many women with MR, TR, and multivalve regurgitation do well during pregnancy, additional clinical variables help stratify those at highest risk. This new information will enhance the quality and precision of preconception counseling and pregnancy planning.

STratification risk analysis in OPerative management (STOP score) for drug-induced endocarditis.

The opioid epidemic has seen a drastic increase in the incidence of drug-associated infective endocarditis (IE). No clinical tool exists to predict operative morbidity and mortality in patients undergoing surgery. A multi-institutional database was reviewed between 2011 and 2018. Multivariate logistic regression was fitted in an automated stepwise fashion. The STratification risk analysis in OPerative management of drug-associated IE (STOP) score was constructed. Morbidity was defined as reintubation, prolonged ventilation, pneumonia, renal failure, dialysis, stroke, reoperation for bleeding, and a permanent pacemaker. Cross-validation provided an unbiased estimate of out-of-sample performance. A total of 1181 patients underwent surgery for drug-associated IE (median age, 39; interquartile range [IQR], 30-54, 386 women [32.7%], 341 reoperations for prosthetic valve endocarditis [28.9%], 316 patients with multivalve disease [26.8%]). Operative morbidity and mortality were 41.1% and 5.9%, respectively. Predictors of morbidity were dialysis (95% confidence interval [CI], 1.16-2.82), emergent intervention (1.83-4.73), multivalve procedure (1.01-1.98), causative organisms other than Streptococcus (1.09-2.02), and type of valve procedure performed [aortic valve procedure (1.07-2.15), mitral valve replacement (1.03-2.05), tricuspid valve replacement (1.21-2.60)]. Predictors of mortality were dialysis (1.29-5.74), active endocarditis (1.32-83), lung disease (1.25-5.43), emergent intervention (1.69-6.60), prosthetic valve endocarditis (1.24-3.69), aortic valve procedure (1.49-5.92) and multivalve disease (1.00-2.95). Variables maximizing explanatory power were translated into a scoring system. Each point increased odds of morbidity and mortality by 22.0% and 22.4% with an accuracy of 94.0% and 94.1%, respectively. Drug-related IE is associated with significant morbidity and mortality. An easily-applied risk stratification score may aid in clinical decision-making.

COMBINED MITRAL AND TRICUSPID STENOSIS IN 47-YEAR OLD RHEUMATIC VALVULAR HEART DISEASE PATIENT: A CASE REPORT

Background: Rheumatic valvular heart disease is a common complication of rheumatic fever; however combined mitral and tricuspid stenosis is an extremely rare form of multi-valve disease presentation. Case Presentation: We report a case of combined mitral and tricuspid stenosis from rheumatic heart disease (RHD) in a 47-year-old woman who was being managed for hypertensive heart disease (HHDx) on anti-hypertensives for 2yrs prior to presentation. However, on further review with transthoracic echocardiography (TTE), she was found to have thickened mitral valve and hockey stick appearance with dilated left atrium (dimension of 60mm) and reduced left ventricular ejection fraction (LVEF) of 45%. A repeat TTE done 8 years after the first one showed a severely dilated left atrium (LAD 71mm) with estimated area of 55.4cm2; moderate mitral stenosis and severe tricuspid stenosis with moderate TR. The LVEF was 29% with a severe right ventricular (RV) systolic dysfunction (TAPSE of 9mm). Patient is being managed conservatively due to economic constraints and the likelihood of very poor surgical outcome due to severe biventricular dysfunction. Conclusion: The case is reported for its rarity as well as the importance of interval evaluation of unaffected valves in a setting of single valve disease for early detection and possible prompt treatment and intervention.

Pregnancy outcomes in women with mechanical heart valves

Abstract Background Mechanical heart valves (MHV) and their absolute need for adequate anticoagulation poses a challenge for pregnancy, either due to warfarin fetotoxicity or an increased risk of maternal thromboembolism. This represents a unique patient (P) group where data is scarce and maternal and fetal risks and benefits must be carefully weighed. Purpose To assess maternal and perinatal outcomes in women with MHV on different anticoagulant regimens and compare them with patients with other types of valvular heart disease (VHD). Methods A retrospective analysis of 131 pregnancies in 83 women with VHD (mean age 26.5±5.6 years) was carried out in a tertiary referral centre from 2000 to 2019. 92 pregnancies with VHD, including 11 with biological prosthetic valves, and 39 pregnancies in 22 P with MHV were identified. The main outcome measures were major maternal complications and perinatal outcome. Results MHV implanted were in mitral position (89.7%), aortic (2.6%), or both (7.7%). History of rheumatic heart disease was identified in 16 P (72.7%) and a congenital etiology was present in 2 P (9.1%). 9 P (40.9%) were on warfarine and 13 P (59.1%) on acenocumarol. Regarding anticoagulation strategy, 21 P (65.6%) remained on oral anticoagulation and 10 P (31.3%) had been switched to some form of heparin during part or the entire pregnancy. Mechanical valve thrombosis complicated pregnancy in 4 patients (10.2%), all cases on heparin, and resulted in maternal death in 1 P. MHV P had more hemorrhagic complications (15.4 vs 2.2%, p=0.004) requiring transfusion or surgical revision. MHV P tended to experience more NHYA class worsening demanding initiation or intensification of cardiac medication (17.9 vs 5.4%, p=0.023). Also in the MHV group there was a higher incidence of miscarriage (46.2 vs 12.0%, p≤0.0005), comprising spontaneous abortion (31.6 vs 7.6%, p&amp;lt;0.0005) and fetal malformations (18.4 vs 5.4%, p=0.028), including warfarin embryopathy (10.3 vs 1.1%, p=0.012). The live birth rate was higher in women on heparin compared with those on warfarin (85.9 vs 79.2%, p=0.002). The presence of multivalve disease (p=0.04), mechanical protheses (p&amp;lt;0.001), ACO (p&amp;lt;0.001) and previous impaired LVEF (p=0.02) were related to miscarriage. In multivariate analysis, ACO was the unique independent predictor of unsuccessful pregnancy (p=0.01). Only 29% of the patients with an MHV had a pregnancy free of serious adverse events compared with other types of VHD (81.5%, p&amp;lt;0.0005). Conclusions MHV remains a challenging condition for pregnancy with only 29% chance of experiencing an uncomplicated pregnancy with a live birth. The increased morbimortality warrant extensive prepregnancy counseling with prosthesis type discussion,centralization of care and further larger studies to come up with evidence-based recommendations. Funding Acknowledgement Type of funding source: None

Imaging Challenges in Secondary Mitral Regurgitation

Chronic secondary mitral regurgitation (SMR) is a complex entity that is often clinically underappreciated.1 It complicates either ischemic heart disease or dilated cardiomyopathy; its prevalence varies among series but may reach ≤50% in patients with heart failure.2 When present, SMR may exhibit a broad range of severity and confers an adverse prognosis, which is worse with increasing severity of mitral regurgitation (MR).3,4 The management of SMR poses a unique set of challenges, based partly on the complexity of the valve disorder and the still-evolving adoption of the optimal therapeutic approach.5 Noninvasive imaging and, in particular, echocardiography, plays a critical role for the initial and longitudinal assessment, for individual risk stratification and outcome prediction, and for guiding intervention in patients with chronic SMR.6 SMR develops because of a combination of mitral leaflet tethering secondary to left ventricular (LV) dilatation/deformation with papillary displacement/discoordination, annular dilatation/dysfunction, insufficient LV-generated closing forces attributable to reduction of LV contractility, and global LV/papillary muscle dyssynchrony.1,5 Tethering of the mitral leaflets is the principal lesion of SMR and results in restriction of systolic leaflet motion, namely type IIIb of Carpentier’s classification. SMR does not typically occur in global LV dysfunction without tethering. However, once tethering occurs, leaflet closure is further impaired by LV dysfunction because there is decreased force opposing tethering.6–9 The key event in the pathogenesis of SMR is the distortion of normal LV geometry—regional and global LV remodeling—with subsequent apical and lateral displacement of papillary muscles, which, in turn, draws the chordae tendineae away from the line of coaptation.7,8 The extent of LV systolic dysfunction and dilatation is weakly correlated to the degree of SMR unless accompanied by geometric distortion in the region of the papillary muscles.1,9 …

Management of multivalvular heart disease

Multivalvular heart valve disease is not an uncommon situation. Although many studies include only patients with regurgitation or stenosis involving only one heart valve, several scenarios in which patients present with regurgitation and/or stenosis involving two or more valves exist. Data on multivalve disease are scarce because of a large number of possible combinations and also owing to difficulties of exact quantification and an overlap in surgical indications. Therefore, many fields related to multiple valve disease are not encountered in the current valvular heart disease guidelines. This article aims to explain multi valvular heart disease from etiology and background definition to surgical outcome, with special emphasis on echocardiographic assessment.

To Study the Maternal and Neonatal Outcomes of Pregnancies complicated by Rheumatic Heart Disease

ABSTRACTObjectivesTo study the maternal and neonatal outcomes of pregnancies complicated by rheumatic heart disease (RHD).Materials and methodsA retrospective study was carried out in the obstetric and cardiology outpatients department of Sir Sunder Lal Hospital, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India over a period of 1 year (Dec 2011-2012) involving 96 pregnant patients with rheumatic heart disease. Their maternal and fetal outcomes were reviewed.ResultsA total of 96 pregnant mothers with heart disease presented to us during the period of 1 year (Dec 2011-2012). Majority of the pregnant mothers had mitral stenosis n = 46 (47%). Rest of the patients had multivalve disease. Pulmonary arterial hypertension was found to be in 28 patients (29%). Atrial thrombus was seen in the echocardiography of one patient. Mitral valve replacement was done before pregnancy in 16 mothers (16%); these gravid mothers were put on low-molecular weight hepanin (LMWH) and during the midtrimester on the Acitrom. There was one patient admitted with atrial fibrillation. New York Heart Association (NYHA) class I and II heart disease progressed in two patients to class III and IV. There was no maternal or fetal mortality in this study. There were 24 cesarean sections (25%) done out of which 8 were for intrauterine growth restriction (IUGR) (32%), rest were due to maternal reasons. There were 12 preterm deliveries. Four fetuses had intraventricular hemorrhage.ConclusionDespite no maternal and neonatal mortality, pregnancy in women with heart disease is associated with significant maternal and neonatal morbidities.How to cite this articlePandey U. To Study the Maternal and Neonatal Outcomes of Pregnancies complicated by Rheumatic Heart Disease. Int J Infertil Fetal Med 2014;5(3):92-94.

Percutaneous double-valve balloon valvotomy for multivalve stenosis: Immediate results and intermediate-term follow-up

Ten patients each with combined mitral and tricuspid stenosis (group 1) and with combined mitral and aortic stenosis (group 2) underwent double-valve balloon valvotomy as a single staged procedure. The aortic valve was dilated by the Mansfield balloon technique, whereas the mitral and tricuspid valves were dilated with either the Mansfield or Inoue balloon. The mitral valve area increased from 0.78 ± 0.21 cm 2 to 2.05 ± 0.56 cm 2 ( p < 0.0005) in group 1 and from 0.75 ± 0.20 cm 2 to 2.1 ± 0.59 cm 2 ( p < 0.05) in group 2. The tricuspid valve area increased from 1.11 ± 0.41 cm 2 to 2.52 ± 0.69 cm 2 ( p < 0.0005). In group 2, the transaortic gradient decreased from 93.56 ± 17.7 mm Hg to 28.56 ± 7.8 mm Hg ( p < 0.0005) and the valve area increased from 0.37 ± 0.05 cm 2 to 1.03 ± 0.25 cm 2 ( p < 0.005). The excellent symptomatic and hemodynamic results were sustained at 30.3 ± 9.8 months of follow-up in group 1 and at 23.5 ± 9.1 months in group 2. Double-valve balloon valvotomy is feasible and safe and provides excellent immediate and intermediate-term follow-up results in selected patients with multivalve disease. A longer follow-up in a larger number of cases is needed to define further the role of this therapy. (Am Heart J 1997;133:64-70.)

Rheumatic mitral stenosis

Rheumatic mitral stenosis remains an important cause of exertional dyspnea, pulmonary congestion, atrial fibrillation, and stroke. Detection rests on careful auscultatory examination and detailed review of chest films. Diagnosis is confirmed by echocardiographic examination; cardiac catheterization is important in symptomatic patients to evaluate the severity of stenosis and associated lesions. Treatment of pulmonary congestion and control of heart rate in patients with atrial fibrillation remain major medical goals. Percutaneous balloon commissurotomy is preferred for most patients with predominant mitral stenosis and for those with contraindications to valve replacement. Implantation of a prosthetic valve is best for patients with significant mitral regurgitation, multivalve disease, associated coronary artery disease that requires bypass, or mitral valve deformity too severe to allow adequate balloon commissurotomy.

Multicenter experience with balloon mitral commissurotomy. NHLBI Balloon Valvuloplasty Registry Report on immediate and 30-day follow-up results. The National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry Participants.

Balloon mitral commissurotomy can increase mitral valve areas and reduce symptoms in selected patients with mitral stenosis. The National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry was organized to address concerns regarding differences in patient selection and technique and to report the current clinical outcome. In 24 cooperating centers, 738 patients had balloon mitral commissurotomy. Baseline clinical, echo Doppler, and cardiac catheterization data, procedure details, and hemodynamic and 30-day clinical outcome were reported. Overall, 81% of the patients were women (mean age, 54 +/- 15 years), and 24% had moderate or severe other valvular lesions. When single- and double-balloon procedures were compared, the final mitral valve area was larger (1.7 +/- 0.7 versus 2.0 +/- 0.8 cm2, p = 0.0009), increase in mitral regurgitation was similar (4% versus 12%, p = 0.08), and interatrial shunts occurred more frequently (2% versus 12%, p = 0.04) after double-balloon procedures. Increase in mitral valve area was weakly related to mitral valve morphology as assessed by an echo score (r = -0.15). Multivariate predictors of improved clinical status at 30 days were cases performed in larger-volume centers, baseline mitral valve area greater than 0.5 cm2, and age less than 70 years. At 30-day follow-up, 4% of the patients with completed procedures had mitral valve surgery, 3% had died, and 83% had their overall condition improved. Patients with mixed mitral stenosis or regurgitation and isolated mitral stenosis had a similar course, but fewer patients with multivalve disease became asymptomatic. Balloon mitral commissurotomy, as practiced in a broad range of experienced centers, produced significant short-term hemodynamic and clinical improvements. Balloon mitral commissurotomy can be considered an effective treatment option in patients with symptomatic mitral stenosis.

Clinical, hemodynamic, and angiographic predictors of operative mortality in patients undergoing single valve replacement

Preoperative characteristics of 964 patients in the Veterans Administration Cooperative Study on Valvular Heart Disease undergoing single valve replacement were examined to determine predictors of operative mortality. The operative mortality rate was 8.3% in 661 patients having isolated aortic valve disease and 7.5% in 239 patients having isolated mitral valve disease, but 12.5% in 64 patients with multivalve disease undergoing single valve replacement. For the aortic valve replacement subgroup, three-vessel coronary artery disease, left ventricular systolic pressure, prior cardiac operation, body surface area, and cardiac index were related to operative mortality. In the mitral valve replacement group, there was a strong association of operative mortality with advanced age, exertional dizziness, reduced cardiac index, left ventricular contraction grade, ST segment depression on the resting electrocardiogram, and pleural effusion. The risk of operative death for an individual patient undergoing aortic or mitral valve replacement may be estimated with the use of independent risk factors.

Isolated replacement of the mitral valve with the Starr-Edwards prosthesis: An eleven-year review

Isolated mitral valve replacement with the Starr-Edwards prosthesis has been performed on 657 patients at the Mayo Clinic during the 11 year period ending January, 1972. The most recent subset of that series comprised patients who received the Model 6120 prosthesis. In this group, the operative mortality rate was 9 per cent and the actuarial late death rate at 5 years was 20 per cent. This survival rate is a significant improvement over the natural history of severe mitral valve disease. Factors associated with operative deaths are large left artrial size, advanced functional class, and previous heart surgery. Variables associated with higher incidence of late deaths are large left atrial size, patient age at operation, and multivalve disease. Risk of thromboembolism is increased with large left atrial size, presence of left atrial thrombus, and inadequate anticoagulant therapy.