Biological Mitral Valve Replacement Research Articles

Lingual artery thrombosis as a presentation of infective endocarditis in a pregnant patient; a case report

Abstract Background Infective endocarditis during pregnancy is a rare condition that compromises the health of both the mother and the fetus, presenting high rates of morbidity and mortality. The clinical manifestations of this disease are varied, with embolic phenomena being a frequent presentation. Case summary We report the case of a 37-year-old patient, at 29 weeks of pregnancy, with no known cardiovascular history, who presented with 48 hours of sudden mandibular and lingual pain. The study showed acute thrombosis of the right lingual artery and the rest of the right external carotid artery. In this context, searching for the origin of the embolism, acute mitral valve endocarditis was diagnosed, which was effectively treated with antibiotic therapy and biological mitral valve replacement, as well as early cesarean delivery. Discussion We report the first case where lingual artery thrombosis was the key diagnostic feature of infective endocarditis.

Comparison of mid-to-long term outcomes between mitral valve repair and biological valve replacement in patients over 60 with rheumatic mitral valve disease based on a propensity score matching study

Objective: To compare and discuss the mid-to-long-term outcomes of mitral valve repair (MVP) versus biological mitral valve replacement (bMVR) in patients over 60 years old with rheumatic mitral valve disease. Methods: This is a retrospective cohort study. A total of 765 patients aged 60 years and older, diagnosed with rheumatic mitral valve disease and who underwent MVP or bMVR at Beijing Anzhen Hospital from January 2010 to January 2023, were retrospectively included. Among them, 186 were male and 579 were female, with an age of (66.1±4.5) years (range: 60 to 82 years). Patients were divided into two groups based on the surgical method: the mitral valve repair group (MVP group, n=256) and the bioprosthetic mitral valve replacement group (bMVR group, n=509). A 1∶1 propensity score matching was performed using a caliper value of 0.2 based on preoperative data. Paired sample t-tests, χ² tests, or Fisher's exact tests were used for intergroup comparisons. Kaplan-Meier method was employed to plot survival curves and valve-related reoperation rate curves for both groups before and after matching, and Log-rank tests were used to compare the mid-to long-term survival rates and valve-related reoperation rates between the two groups. Results: A total of 765 patients who completed follow-up were ultimately included, with a follow-up period (M(IQR)) of 5.1(5.0) years (range: 1.0 to 12.9 years). After matching, each group consisted of 256 patients. The incidence of early postoperative atrial fibrillation (39.1% vs. 49.2%, χ2=4.95, P=0.026) and early mortality rates (2.0% vs. 6.2%, χ2=4.97, P=0.026) were lower in the MVP group. Unadjusted Kaplan-Meier analysis showed significantly higher 5-year and 10-year survival rates for the MVP group (92.54% vs. 83.02%, 86.22% vs. 70.19%, Log-rank P=0.001). After adjustment with propensity scores, the Kaplan-Meier analysis still indicated higher 5-year and 10-year survival rates in the MVP group compared to the bMVR group (92.54% vs. 85.89%, 86.22% vs. 74.83%, Log-rank P=0.024). There were no significant differences in the rates of valve-related reoperation between the two groups before and after matching (5-year and 10-year reoperation rates pre-matching: 1.75% vs. 0.57%, 5.39% vs. 7.54%, Log-rank P=0.207; post-matching: 1.75% vs. 0%, 5.39% vs. 9.27%, Log-rank P=0.157). Conclusion: For patients over 60 with rheumatic mitral valve disease, mitral valve repair offers better mid-to-long-term survival compared to biological valve replacement.

Mechanical versus biological mitral valve replacement: Insights from propensity score matching on survival and reoperation rates

ObjectivesPatients with symptomatic mitral valve disease unsuitable for repair can be sufficiently treated with surgical mitral valve replacement. The decision between biological and mechanical mitral valve replacement can be difficult, especially due to the question of the lesser of 2 evils: anticoagulation versus reoperation. MethodsThis single-center, retrospective study included all patients undergoing mitral valve replacement between 2001 and 2020. Thirty-day mortality and periprocedural complications were analyzed. Propensity score matching adjusted for age, gender, weight, height, endocarditis, diabetes, hypertension, peripheral arterial occlusive disease, atrial fibrillation, chronic kidney disease, cancer, and history of neurological disorders was performed. After propensity score matching, survival and cumulative incidence of reoperation at time of follow-up were analyzed. ResultsThe study included 2027 patients in 2 main groups: 1658 patients with biological mitral valve replacement and 369 patients with mechanical mitral valve replacement; 51.2% were male. Age at surgery was 65.9 ± 12.9 years. Median follow-up time was 6.83 years (interquartile range, 1.11-10.61 years). Concomitant procedures were performed in 1467 cases (72.4%). Propensity score matching yielded comparable groups of 339 pairs. Both groups showed comparable survival (P = .203). Survival after mechanical mitral valve replacement and biological mitral valve replacement was comparable for all analyzed time points over the course of 20 years. Patients with mechanical mitral valve replacement showed a significantly lower cumulative incidence for reoperation (20 years: 15% vs 59%, P < .001). ConclusionsFollow-up of 20 years at a high-volume center demonstrates comparable survival after mechanical or biological mitral valve replacement, whereas reoperation rates are significantly lower after mechanical mitral valve replacement.

Effects of mitral valve disease etiology on the outcomes of mechanical and biological valve replacement: retrospective cohort study.

The choice of an artificial mitral valve (MV) is a crucial clinical decision that affects the long-term survival and quality of life of patients. However, current guidelines recommend selecting MV based on patient age and life expectancy at the time of MV replacement (MVR), without considering the etiology of MV disease. This study aimed to investigate whether MV disease etiology should be considered when choosing a valve for MVR and to evaluate the impact of MV disease etiology on long-term patient survival. Using data (2002 to 2018) from Taiwan's National Health Insurance Research Database, we conducted a nationwide retrospective cohort study to compare the biological and mechanical valves in terms of all-cause mortality as the primary outcome. The inverse probability of the treatment weighting method was used to reduce the effects of the confounding factors. The following etiologies were assessed: infective endocarditis (IE), rheumatic heart disease (RHD), ischemic mitral regurgitation (IMR), and degenerative mitral regurgitation (DMR). In patients aged <70 years, it was observed that mechanical valves demonstrated an association with benefits compared to biological valves in the context of survival. In patients with IE aged <72 years, mechanical valves were associated with survival benefits, but not in those with stroke during hospitalization. These valves were also found to be linked with survival advantages for patients with RHD aged <60 years and for those with DMR aged < 72 years. However, no age-dependent effects of valve type on all-cause mortality were observed in patients with IMR. The etiology of MV disease appears to be important in the selection of a suitable MV and determination of a cutoff age for mechanical and biological MVR.

Long-Term Outcomes Stratified by Age in Patients with a Mechanical versus Biological Mitral Valve Replacement.

Objectives: Balancing anticoagulation and reoperation risks determines prostheses choice (mechanical/biological) for mitral valve replacement. We aimed to re-evaluate the outcomes after biological versus mechanical mitral valve replacement. Methods: We compared long-term benefits and risks of mechanical and biological prostheses in 2056 patients (52% men, 48% women; 65.4 ± 12.1 years) who underwent mitral valve replacements between 1993–2017, in a retrospective single-centre study. Data sources included prospective institutional database, social registry, general practitioner data and follow-up questionnaire. Patients were stratified by age: < = 39 y (n = 82), 40–49 y (n = 164), 50–59 y (n = 335), 60–69 y (n = 593), 70–79 y (n = 743) and > = 80 y (n = 139). Long-term outcomes (mortality, reoperations, bleeding) were analysed. Results: Altogether, 1308 mechanical (53% men, 47% women; 61.5 ± 11.7 years) and 748 biological (50% men, 50% women; 72.3 ± 9.6 years) valves were implanted. The reason for valve replacement was stenosis in 162, insufficiency in 823 and combined in 323 cases for mechanical, while it was 46, 567 and 135 for biological valves, respectively. Overall cumulative survival was higher with mechanical prosthesis (mean: 139 ± 4 vs. 102 ± 5 months, 10 y: 55% vs. 33%, p < 0.0001). Subgroup analysis revealed higher survival among patients receiving mechanical prosthesis up to 60 years (< = 39 y p = 0.047, 40–49 y p < 0.0001, 50–59 y p = 0.001). In patients 60–69 years, overall survival did not differ; however, in survivors beyond 8 years, mechanical prosthesis showed improved survival (p = 0.014). While between 70–79 years survival was nearly identical, for above 80 years, patients had a higher survival with biological prosthesis (p = 0.014). Conclusion: The present data demonstrated a higher survival of mechanical prosthesis in a wide range of patients after mitral valve replacement.

Transillumination Rendering of a Prosthetic Mitral Valve Endocarditis

A 61-year-old man presented in mid-2019 to the emergency department complaining of high-grade fever, chills, and malaise 4 days before his visit. He had a history of hypertension and a biological mitral valve replacement in 2016 as treatment for a severe mitral regurgitation. Cardiac auscultation and physical examination were noncontributory. A late endocarditis of the prosthetic mitral valve was suspected. Hemocultures taken in the first hour were positive for Streptococcus viridans and S. pneumoniae.

Massa Valvar Mitral em Paciente com Suspeita de Lúpus Sistêmico: Tumor, Endocardite ou Ambos?

ResumoApresentamos o relato de caso de uma paciente com mixoma valvar mitral infectado e uma revisão da literatura sobre o assunto. Uma mulher de 33 anos apresentou histórico de febre e dispneia com evolução de alguns dias. Na hospitalização, ela apresentava uma síndrome semelhante ao lúpus, com hemoculturas positivas para Haemophilus spp . O ecocardiograma revelou uma massa gigante envolvendo ambos os folhetos mitrais associada à regurgitação grave, necessitando de troca valvar mitral biológica. A microscopia revelou mixoma infectado e a paciente recebeu alta assintomática após o término da antibioticoterapia. Ela apresentou bons resultados no seguimento. Este é o sexto caso de mixoma valvar mitral infectado relatado na literatura e o terceiro caso de mixoma cardíaco infectado pelo grupo HACEK. Devido à alta incidência de eventos embólicos, a antibioticoterapia precoce aliada à pronta intervenção cirúrgica são decisivos para a redução da morbimortalidade. O tempo para o diagnóstico foi muito mais breve do que o geralmente relatado em casos de endocardite por HACEK. A troca valvar foi a intervenção mais comum e todos os pacientes em relatos de caso anteriores apresentaram bons resultados no seguimento.

Bioprosthetic vs mechanical mitral valve replacement for infective endocarditis in patients aged 50 to 69 years

BackgroundThe optimal choice of the valve prosthesis in mitral valve replacement (MVR) for infective endocarditis (IE) is controversial and challenging, particularly for younger patients.HypothesisThe postoperative outcomes of mechanical and biological MVR in IE patients aged 50 to 69 years are different.MethodsAll IE patients aged 50 to 69 years with primary MVR in Hubei province hospitals from 2002 to 2018 were retrospectively reviewed. The median duration of follow‐up was 8.7 years (IQR, 6.8‐10.9 years). Propensity score matching (1:3 ratio) was used to yield 492 patients with comparable baseline features between bioprostheses and mechanical prosthetic valve groups. Outcomes were postoperative mid‐ to long‐ term survival, mitral valve reoperation, prosthetic valve endocarditis (PVE), stroke, and major bleeding events.ResultsFifteen‐year survival after MVR was 80.6% in the mechanical valve group and 69.3% in the bioprostheses group (HR 0.545, P = .040). The cumulative incidence of mitral valve reoperation was 8.8% with mechanical valves and 21.4% with bioprostheses (HR 0.260, P = .002). The cumulative incidence of PVE was 5.6% with mechanical valves and 7.2% with bioprostheses (HR 0.629, P = .435). The cumulative incidence of stroke was 12.9% with mechanical valves and 10.5% with bioprostheses (HR 1.217, P = .647). The cumulative incidence of major bleeding was 12.0% with mechanical valves and 6.75% with bioprostheses (HR 1.579, P = .268).ConclusionsMechanical valve prostheses were associated with better survival, lower rates of reoperation compared with bioprostheses within 15 years after MVR in IE patients aged 50 to 69. These findings suggest mechanical valve prostheses may be a more reasonable alternative to bioprostheses in this patient group.

P1322 Role of echocardiography in the assessment of mechanical complications of acute myocardial infarction: case report series

Abstract INTRODUCTION The incidence of the mechanical complications of acute myocardial infarction (AMI) has noticeably decreased throughout the world after the era of primary percutaneous coronary intervention (PCI); nonetheless, when they present, the mortality rate continues being high, requiring for their diagnosis an adequate clinical suspicion, followed by intensive care therapy and in most cases, surgical treatment. In the current report we present 4 cases of mechanical complications using transthoracic echocardiography (TTE) as diagnostic tool: a ventricular septal defect, a papillary muscle rupture, a left ventricular (LV) free wall rupture and a ventricular aneurysm. PATIENT 1: A 71-year-old male who presented with inferior AMI and no reperfusion therapy, complicated with transitory AV block, ventricular fibrillation and severe mitral regurgitation secondary to posteromedial papillary muscle rupture (Panel A). He followed surgery with biological mitral valve replacement and PCI of the right coronary artery (RCA). PATIENT 2: A 71-year-old male who presented with anterior AMI and no reperfusion therapy, suddenly showed signs of cardiogenic shock. The TTE demonstrated pericardial effusion associated with an image of thrombus fixed to the antero-apical wall of the LV of 21 mm in dimension, apical segments akinesia and left ventricular ejection fraction (LVEF) of 40% (Panel B). These findings concluded LV free wall rupture, that required urgent surgical repair of the apical region with sphacelated myocardium. PATIENT 3: A68-year-old male, with history of hospitalization 2 months prior for an event of acute coronary syndrome. Admitted again for chest pain, with a TTE that demonstrated a ventricular septal defect associated with intramyocardial dissection, apical thrombus of 17x11 mm in dimension, apical dyskinesis and LVEF of 30% (Panel C). Coronary angiography documented critical obstruction of proximal left anterior descending coronary artery (LAD) and chronic total occlusion of the RCA. He was taken to surgical repair of the defect and coronary artery bypass (CABG). PATIENT 4: A 77-year-old male, with a history of PCI in 2009 (unknown coronary vessel), presented with inferior AMI and no reperfusion therapy. TTE demonstrated an aneurysm in the basal inferior segment of 55x44 mm in dimension, partially thrombosed, with a neck of 23 mm, severe mitral regurgitation and LVEF of 45% (Panel D). Coronary angiography documented multivessel disease with unsuitable coronary anatomy for CABG. CONCLUSIONS The incidence of AMI mechanical complications has decreased noticeably to less than 1% in the era of primary PCI. These include free wall rupture (0.17%), papillary muscle rupture (0.26%) and LV free wall rupture (0.17%). Immediate echocardiographic assessment is needed when clinical findings suggest such complications; urgent treatment is fundamental to improve short term prognosis. Abstract P1322 Figure. Bidimensional TTE images.

Transcatheter mitral valve replacement: current status

After aortic valve stenosis, mitral regurgitation (MR) is the second most common valvular disease, particulary affecting older patients. Optimal medical treatment within the context of heart failure therapy is the favored first-line therapy for secondary MR. If symptoms persist despite optimal medical therapy, surgical or transcatheter mitral valve repair is indicated (recommendation class IIb). In contrast, surgical treatment is essential for patients with symptomatic primary MR and left-ventricular ejection fraction (LVEF) >30% and justifiable perioperative risk (repair preferred over replacement, recommendation classI); for high-risk patients, interventional transcatheter mitral valve repair (especially by "edge-to-edge-reconstruction") is aviable option (recommendation class IIb).Recently, transcatheter mitral valve replacement (TMVR) has come into focus as another attractive treatment option and is currently under intensive research. At first, the TMVR was used both for patients with symptomatic insufficiency or stenosis after biological mitral valve replacement (Bio-MKE) or after reconstruction as a"valve-in-valve" or "valve-in-ring" procedure. Therefore, transcatheter aortic valve prostheses were used.In the past few years several dedicated TMVR prostheses were developed for the treatment of native MR. So far, no TMVR prosthesis is CE-certified. All of the following TMVR methods are under clinical evaluation in the scope of pivotal trials. The interdisciplinary heart team, consisting of experienced cardiologists and heart surgeons develops apatient-specific, individual treatment concept considering the particular MR etiology, pre-existing comorbidities, age, clinical symptoms, and status.

Impact of valve type on outcomes after redo mitral valve replacement in patients aged 50 to 69 years

Little data are available with regard to valve selections in redo valvular surgery. We investigated the impact of valve types on late outcomes after redo mitral valve replacement (MVR). We retrospectively reviewed 66 patients aged 50-69 (mean age 62.2 ± 5.1) years who underwent redo MVR over the past 25 years. In redo MVR, 46 (69.7%) redo procedures were the 1st redo valvular surgeries, 16 (24.2%) were 2nd redos, 3 (4.5%) were 3rd redos and 1 was a 4th (1.5%) redo. We classified 66 patients into 2 groups: mechanical MVR group (M-MVR, n = 44) and biological MVR group (B-MVR, n = 22). The mean follow-up period was 8.2 ± 6.3 years. Hospital mortality rates were 3.3% in M-MVR and 9.7% in B-MVR (P = 0.3328). Survival rates in M-MVR and B-MVR at 5 and 10 years were 93.0 ± 4.8% vs 76.0 ± 10.5% and 77.6 ± 9.1% vs 51.3 ± 13.7%, respectively (log-rank test, P = 0.0072). Late death occurred in 7 patients in M-MVR and 9 in B-MVR. Freedom rates from valve-related events in M-MVR and B-MVR at 5 and 10 years were 100.0 ± 0.0% vs 76.5 ± 10.3% and 93.3 ± 6.4% vs 52.4 ± 13.6%, respectively (log-rank test, P < 0.0001). No bleeding and thromboembolic events were observed in M-MVR, whereas gastrointestinal bleeding (n = 1), subarachnoid haemorrhage (n = 1) and cerebral infarction (n = 2) were observed in B-MVR. A predictor of late death was a biological valve in redo MVR (P = 0.0206, hazard ratio = 3.402, 95% confidence interval 1.207-9.591). It would seem that redo MVR using a mechanical valve was associated with better early and late outcomes in this age group.

Is Surgical or Catheter-based Interventions an Option After an Unsuccessful Mitral Clip?

The objective of this study was to assess the results of catheter-based and surgical reinterventions in primary mitral regurgitation after failed MitraClip therapy. We report on 21 consecutive symptomatic patients with primary mitral regurgitation (median age 78 years) who underwent either repeat MitraClip therapy (n = 7) or mitral valve surgery (n = 14) after failure of the index procedure with 1-2 MitraClip implantations. At the time of reinterventions, 193 (interquartile range [IQR]: 32-622) days after the index procedure, patients had recurrent or persistent grade 3 mitral regurgitation. Early mortality at 30 days was 4.8%. Cardiac-related survival at 2 years was 85.4% (4 cardiac and 4 noncardiac deaths). Three of 7 patients with percutaneous reintervention were converted to surgery at 34, 52, and 56 days because repeat MitraClip therapy was ineffective because of pre-existing clip detachment or leaflet tear. Final therapy was biological mitral valve replacement in 14 of 21 patients (66.7%); 4 were treated with percutaneous repeat MitraClip repair (19%), and in 3 patients, surgical repairs were performed (14.3%). At follow-up with a median of 708 days, New York Heart Association class had improved significantly to class 2 (IQR: 1.0-2.5) (P = 0.0004), and the left ventricular end-diastolic diameter had decreased from 56 (IQR: 52-59) mm to 51 (48-58) mm (P = 0.0378), respectively. Recurrence of significant mitral regurgitation was absent in all but 1 patient with unsuccessful repeat MitraClip therapy who was deemed inoperable. Our data show that both repeat MitraClip and also mitral valve surgery are feasible and safe alternatives in patients without an excessively increased perioperative risk. We conclude that whenever leaflet insertion is not compromised, repeat catheter-based repair is a reasonable redo concept; in the remaining cases, surgery should be offered to the patient.

The Use of Rapid Deployment Valves in Combined Aortic and Mitral Valve Surgery: One-Year Clinical and Echocardiographic Outcomes.

Patients undergoing multiple valve surgery represent a high-risk group who could potentially benefit from a reduction of cross-clamp and cardiopulmonary bypass times because prolonged bypass and cross-clamp times are considered independent risk factors for increased morbidity and mortality after cardiac surgery. Between July 2013 and November 2014, 16 patients underwent rapid deployment aortic valve replacement with the EDWARDS INTUITY valve system in the setting of concomitant mitral disease. Fifteen patients showed mitral regurgitation, whereas one patient had severe mitral stenosis. Fourteen patients received mitral valve repair and two patients received biological mitral valve replacement. Tricuspid valve repair was performed additionally in two patients. The mean ± SD age was 72.8 ± 8.4 years, and the mean ± SD logistic EuroSCORE II is 8.7% ± 3.4%. Within a 30-day perioperative period, no patient was lost (n = 0). The mean ± SD follow-up time was 11 ± 2 months. At 1 year, the overall survival was 81% (n = 13). A mean ± SD transaortic gradient of 10.7 ± 2.3 mm Hg and a mean ± SD effective orifice area of 1.7 ± 0.3 cm were measured echocardiographically. No higher-grade paravalvular leak (aortic insufficiency > 1+) occurred. Eight patients (61%) had no residual mitral regurgitation, four patients (30%) showed trivial regurgitation (1/4), and one patient (7.3%) had moderate mitral regurgitation (2/4). No interference of the subannular stent frame with the reconstructed valve or the biological mitral prosthesis was seen. Rapid deployment aortic valve replacement with the EDWARDS INTUITY valve system in combined aortic and mitral valve surgery can be performed safely with reproducible results. One-year follow-up data of this small series shows encouraging results potentially justifying the extension of the indication for rapid deployment valves to patients with concomitant mitral disease. Especially elderly patients undergoing multiple valve surgery may benefit from a reduction of cardiopulmonary bypass and myocardial ischemic times.

Mitral valve replacement in patients under 65 years of age: mechanical or biological valves?

There is controversy regarding the optimal choice of prosthetic valves in patients less than 65 years of age requiring mitral valve replacement (MVR). Recently, trends for valve replacement are moving towards biological prosthesis also in younger patients, which is justified by the fact that a later valve-in-valve procedure is feasible in the case of degeneration of the tissue valve. This strategy is increasingly recommended in aortic valve surgery but is questionable for MVR. The purpose of this review is to evaluate current guidelines and analyse evidence for biological MVR in patients under 65 years. There are differences between guidelines of the American Heart Association and those of the European Society of Cardiology concerning the choice of prostheses in patients undergoing MVR. Although the European Society of Cardiology recommends a mechanical mitral valve in patients under 65 years of age, the American Heart Association does not provide detailed advice for these patients. Mitral valve replacement with biological valves in patients under 65 years is associated with higher rates of reoperation due to structural valve deterioration. In addition, several studies showed a decreased survival after biological MVR. Evidence for biological MVR in patients less than 65 years without comorbidities or contraindication for oral anticoagulation does not exist. Recommendations for patients less than 65 years of age should not be blurred by current 'en-vogue' methods for promising but not yet proven valve-in-valve strategies.

Simultaneous mitral valve and lung surgery for complicated endocarditis

A 48-year-old man developed severe sepsis after a chest trauma. The patient suffered from presternal and cervical abscesses, mediastinitis, septic arthritis of the right shoulder, abscesses in the right lung lower lobe and severe infective endocarditis of the mitral valve. After subcutaneous and mediastinal abscess-drainage, hemodynamic stabilization, and control of sepsis, biological mitral valve replacement and concomitant resection of the right lower lobe were performed. Restoration of the shoulder could be performed 22 days later. The patient was discharged after 4 weeks and is well 1 year after surgery.

Thromboembolic Complications After Surgical Correction of Mitral Regurgitation: Incidence, Predictors, and Clinical Implications

We sought to define thromboembolic risk after surgery for mitral regurgitation (MR), particularly ischemic stroke (IS) compared with the general population. Guidelines recommend surgery in asymptomatic patients with MR, but IS risks are unknown. In 1,344 patients (age 65 +/- 12 years) consecutively operated for MR (procedures: 897 mitral valve repair [MRep] and 447 valve replacement: 231 mechanical mitral valve replacement [MVRm], 216 biological mitral valve replacement [MVRb]), thromboembolic complications, particularly IS (diagnosed by neurologists), during follow-up were assessed early (<30 days), midterm (30 to 180 days), and long-term (>or=180 days). Ischemic stroke occurred in 130 patients: 1.9 +/- 0.4% and 2.7 +/- 0.5% at 30 days and 180 days, respectively, and 8.1 +/- 0.8% at 5 years. We found that IS rates were lowest after MRep versus MVRb and MVRm (6.1 +/- 0.9% vs. 8 +/- 2.1%, and 16.1 +/- 2.7% at 5 years, respectively, p < 0.001). Comparison with population-expected IS showed high risk at <30 days (risk ratio 41, 95% confidence interval 26 to 60, p < 0.001 but p > 0.10 between procedures) and moderate risk at >30 days (risk ratio 1.7 overall; 1.3 for MRep; 0.98 for MVRb; 4.8 for MVRm). Beyond 180 days, IS risk declined further and was similar to the population for MRep (relative risk 1.2) and for MVRb (relative risk 0.9). Bleeding risk >30 days was lowest in MRep versus MVRb and MVRm (10-year risk 7 +/- 1%, 14 +/- 4%, and 16 +/- 3%, respectively). Thromboembolic complications after MR surgery are a reason for both concern and encouragement. The risk of IS is notable early, irrespective of procedure, but in the long term it is not greater than in the population after MRep and MVRb. Preference for MRep should be emphasized, and trials aiming at preventing IS should be conducted to reduce thromboembolic and hemorrhagic risk after surgery for MR.

Early Clinical Results After Stentless Mitral Valve Implantation and Comparison With Conventional Valve Repair or Replacement

Background —A new quadricusp stentless mitral bioprosthetic valve (QMV) is evaluated and compared with current standards. Methods and Results —Since August 1997, 67 patients were prospectively evaluated: 23 patients received a QMV, 23 had mitral valve repair (MVR), and 21 received conventional mitral valve replacement (MVP). Patient age was 69±8, 64±10, and 62±9 years for QMV, MVR, and MVP treatment, respectively. The underlying pathology was mitral stenosis, incompetence, and mixed disease in a corresponding 8, 9, and 6 patients for QMV, 1, 22, and 0 patients for MVR, and 2, 12, and 7 patients for MVP. The papillary muscles were sufficient in all QMV cases to suspend the valve. Cross-clamp time was 59±19 minutes for QMV implantation. In-hospital mortality for QMV, MVR, and MVP was 1, 0, and 0 patients, respectively, and thoracotomy had to be performed again in 1, 1, and 2 patients, respectively (these outcomes were not valve related). At baseline transthoracic echocardiography, respective maximum flow velocities were 1.6, 1.4, and 1.7 m/s, and valve orifice area was 2.6, 3.5, and 3.4 cm 2 . Mild transvalvular reflux was seen in 8, 7, and 2 patients; moderate reflux, in 1, 1, and 1 patients. Left ventricular ejection fraction was 52%, 54%, and 51% in the respective treatment groups. At follow-up, hemodynamic parameters had further improved in all groups. Conclusions —One year after clinical implantation, the QMV appears to function well and has no additional risks compared with MVR or MVP. The subvalvular apparatus is preserved by suspending the QMV at the papillary muscles; this arrangement is hemodynamically advantageous. Echocardiography reveals an excellent valve performance that resembles native mitral valve morphology and hemodynamic function. The QMV is a promising alternative for biological mitral valve replacement.