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

PURPOSE OF REVIEW 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. RECENT FINDINGS 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. SUMMARY 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.

Localized amyloid light-chain amyloidosis and extramedullary plasmacytoma of the mitral valve

An unusual case of localized amyloid light-chain (AL) amyloidosis and extramedullary plasmacytoma of the mitral valve is described. The worsening of a mitral regurgitation led to investigations and surgery. The valve presented marked distortion and thickening by type AL amyloid associated with a monotypic CD138+ immunoglobulin lambda plasma cell proliferation. Systemic staging showed a normal bone marrow and no evidence of amyloid deposition in other localizations. The patient's outcome after mitral valve replacement was excellent. To our knowledge, this is the first description of a localized AL amyloidosis as well as of a primary extramedullary plasmacytoma of the mitral valve.

Quantitative multi-slice computed tomography assessment of the mitral valvular complex for transcatheter mitral valve interventions part 1: systematic measurement methodology and inter-observer variability

AIMS Transcatheter mitral valve replacement (TMVR) is an emerging technology with the potential to treat patients with severe mitral regurgitation at excessive risk for surgical mitral valve surgery. Multimodal imaging of the mitral valvular complex and surrounding structures will be an important component for patient selection for TMVR. Our aim was to describe and evaluate a systematic multi-slice computed tomography (MSCT) image analysis methodology that provides measurements relevant for transcatheter mitral valve replacement. METHODS AND RESULTS A systematic step-by-step measurement methodology is described for structures of the mitral valvular complex including: the mitral valve annulus, left ventricle, left atrium, papillary muscles and left ventricular outflow tract. To evaluate reproducibility, two observers applied this methodology to a retrospective series of 49 cardiac MSCT scans in patients with heart failure and significant mitral regurgitation. For each of 25 geometrical metrics, we evaluated inter-observer difference and intra-class correlation. The inter-observer difference was below 10% and the intra-class correlation was above 0.81 for measurements of critical importance in the sizing of TMVR devices: the mitral valve annulus diameters, area, perimeter, the inter-trigone distance, and the aorto-mitral angle. CONCLUSIONS MSCT can provide measurements that are important for patient selection and sizing of TMVR devices. These measurements have excellent inter-observer reproducibility in patients with functional mitral regurgitation.

The future of transcatheter mitral valve interventions: competitive or complementary role of repair vs. replacement?

Transcatheter mitral interventions has been developed to address an unmet clinical need and may be an alternative therapeutic option to surgery with the intent to provide symptomatic and prognostic benefit. Beyond MitraClip therapy, alternative repair technologies are being developed to expand the transcatheter intervention armamentarium. Recently, the feasibility of transcatheter mitral valve implantation in native non-calcified valves has been reported in very high-risk patients. Acknowledging the lack of scientific evidence to date, it is difficult to predict what the ultimate future role of transcatheter mitral valve interventions will be. The purpose of the present report is to review the current state-of-the-art of mitral valve intervention, and to identify the potential future scenarios, which might benefit most from the transcatheter repair and replacement devices under development.

A case of Kingella kingae endocarditis complicated by native mitral valve rupture

We report a case of Kingella kingae endocarditis in a patient with a history of recent respiratory tract infection and dental extraction. This case is remarkable for embolic and vasculitic phenomena in association with a large valve vegetation and valve perforation. Kingella kingae is an organism known to cause endocarditis, however early major complications are uncommon. Our case of Kingella endocarditis behaved in a virulent fashion necessitating a combined approach of intravenous antibiotic therapy and a valve replacement. It highlights the importance of expedited investigation for endocarditis in patients with Kingella bacteraemia.

Changes in Left Ventricular Torsion Early Postoperatively After Aortic Valve Replacement and at Long-Term Follow-up.

OBJECTIVE In patients with aortic stenosis, left ventricular systolic torsion (pT) is increased to overcome excessive afterload. This study assessed left ventricular torsion before and immediately after surgical valve replacement and tested the instant effect of fluid loading. DESIGN Prospective, clinical single-center study. SETTING Intensive care unit of a university hospital. PARTICIPANTS 12 patients undergoing elective aortic valve replacement for aortic stenosis. INTERVENTIONS Echocardiography was performed on the day before surgery, within 18 hours after surgery including a fluid challenge, and after 2.5 years. MEASUREMENTS AND MAIN RESULTS pT decreased early postoperatively by 21.2% (23.4° ± 5.6° to 18.4° ± 6.9°; p = 0.012) and reached preoperative values at 2.5 years follow-up (24 ± 7). Peak diastolic untwisting velocity occurred later early postoperatively (13% ± 8% to 21% ± 9.4%; p = 0.019) and returned toward preoperative values at follow-up (10.2 ± 4.7°). The fluid challenge increased central venous pressure (8 ± 4 mmHg to 11 ± 4 mmHg; p = 0.003) and reduced peak systolic torsion velocity (138.7 ± 37.6/s to 121.3 ± 32/s; p = 0.032). pT decreased in 3 and increased in 8 patients after fluid loading. Patients whose pT increased had higher early mitral inflow velocity postoperatively (p = 0.04) than those with decreasing pT. Patients with reduced pT after fluid loading received more fluids (p = 0.04) and had a higher positive fluid balance during the intensive care unit stay (p = 0.03). Torsion after fluid loading correlated with total fluid input (p = 0.001) and cumulative fluid balance (p = 0.002). CONCLUSIONS pT decreased early after aortic valve replacement but remained elevated despite elimination of aortic stenosis. After 2.5 years, torsion had returned to preoperative levels.

Mitral Valve Surgery for Rheumatic Lesions in Young Patients

BACKGROUND: The appropriateness of rheumatic mitral valve repair remains controversial due to the risks of recurrent mitral dysfunction and need for reoperation. The aims of this study were to determine the overall short- and long-term outcomes of pediatric rheumatic mitral valve surgery in our center. METHODS: Single-center, observational, retrospective study that analyzed the results of rheumatic mitral valve surgery in young patients, consecutively operated by the same team, between 1999 and 2014. RESULTS: We included 116 patients (mean age = 12.6 ± 3.5 years), of which 66 (57%) were females. A total of 116 primary surgical interventions and 22 reoperations were performed. Primary valve repair was possible in 86 (74%) patients and valve replacement occurred in 30 (26%). Sixty percent of the patients were followed up beyond three months after surgery (median follow-up time = 9.2 months [minimum = 10 days; maximum = 15 years]). Long-term clinical outcomes were favorable, with most patients in New York Heart Association functional class I (89.6%) and in sinus rhythm (85%). Freedom from reoperation for primary valve repair at six months, five years, and ten years was 96.4% ± 0.25%, 72% ± 0.72%, and 44.7% ± 1.34%, respectively. Freedom from reoperation for primary valve replacement at six months, five years, and ten years was 100%, 91.7% ± 0.86%, and 91.7% ± 0.86%, respectively. Mitral stenosis as the primary lesion dictated early reintervention. CONCLUSIONS: Despite the greater rate of reoperation, especially when the primary lesion was mitral stenosis, rheumatic mitral valve repair provides similar clinical outcomes as compared with replacement, with the advantage of avoiding anticoagulation.

Two Cases of Late Shone Syndrome With Pulmonary Hypertension: Heart-Lung Transplant or Valve Surgery?

Two cases of Shone syndrome with severe mitral and aortic valve problems and pulmonary hypertension were referred for heart-lung transplantation. Severely elevated pulmonary vascular resistance (PVR) was confirmed as was severe periprosthetic mitral and aortic regurgitation. Based on the severity of the valve lesions in both patients, surgery was decided upon and undertaken. Both experienced early pulmonary hypertensive crises, one more than the other, that gradually subsided, followed by excellent recovery and reversal of pulmonary hypertension and PVR. These cases illustrate Braunwald's concept that pulmonary hypertension secondary to left-sided valve disease is reversible.

Prosthetic Mitral Valve Thrombosis in Pregnancy: From Thrombolysis to Anticoagulation

INTRODUCTION: Pregnant women with mechanical prosthetic heart valves are at increased risk for valve thrombosis. Management decisions for this life-threatening complication are complex. Open-heart surgery has a very high risk of maternal mortality and fetal loss. Bleeding and embolic risks associated with thrombolytic agents, the limited efficacy of thrombolysis in certain subgroups, and a lack of experience in the setting of pregnancy raise important concerns. CASE REPORT: We report a case of mitral prosthetic valve thrombosis in early pregnancy, which was successfully treated with streptokinase. Ten years later, the same patient had an uneventful pregnancy, throughout which acenocoumarol was maintained. CONCLUSION: With this case we review the prevention (with oral anticoagulant therapy) and treatment of prosthetic valve thrombosis during pregnancy, which is important for both obstetrician and cardiologist.

Percutaneous Treatment of Mitral Valve Regurgitation: Initial Experience with the MitraClip Device

INTRODUCTION: Mitral regurgitation (MR) is the most common valvular disease and has recently become the target of a number of percutaneous approaches. The MitraClip is virtually the only device for which there is considerable experience, with more than 20,000 procedures performed worldwide. OBJECTIVE: To describe our initial experience of the percutaneous treatment of MR with the MitraClip device. METHODS: We describe the first six MitraClip cases performed in this institution (mean age 58.5 ± 13.1 years), with functional MR grade 4+ and New York Heart Association (NYHA) heart failure class III or IV (n=3), with a mean follow-up of 290 ± 145 days. RESULTS: Procedural success (MR ≤ 2+) was 100%. Total procedure time was 115.8 ± 23.7 min, with no in-hospital adverse events and discharge between the fourth and eighth day, and consistent improvement in the six-minute walk test (329.8 ± 98.42 vs. 385.33 ± 106.95 m) and in NYHA class (three patients improved by two NYHA classes). During follow-up there were two deaths, in two of the four patients who had been initially considered for heart transplantation. CONCLUSION: In patients with functional MR the MitraClip procedure is safe, with both a high implantation and immediate in-hospital success rate. A longer follow-up suggests that the clinical benefit decreases or disappears completely in patients with more advanced heart disease, namely those denied transplantation or on the heart transplant waiting list.

Use of a ventricular septal defect occluder for apical closure in transapical aortic valve replacement.

During transapical transcatheter aortic valve replacement (TA-TAVR), the apical closure remains a challenge for the surgeon, having the risk for ventricular tear and massive bleeding. Apical closure devices are already under clinical evaluation, but only a few can lead to a full percutaneous TA-TAVR. We describe the successful use of a 9-mm myocardial occluder (ventricular septal defect occluder) that was used to seal the apex after a standard TA-TAVR (using the Sapien XT 23-mm transcatheter valve and the Ascendra + delivery system). The placement of the nonmodified myocardial occluder was performed through the Ascendra + delivery system, with a very small amount of blood loss and an acceptable sealing of the apical tear. This approach is feasible and represents a further step toward true-percutaneous transapical heart valve procedures. Modified apical occluders are under evaluation in animal models.

Cost-effectiveness of Transcatheter Mitral Valve Leaflet Repair for the Treatment of Mitral Regurgitation in Heart Failure

Contexte: La régurgitation mitrale (RM) est une maladie valvulaire nécessitant une intervention dans les cas les plus grave. Une réparation percutanée de la valve mitrale avec le dispositif MitraClip est un traitement sécuritaire et efficace pour les patients à haut risque chirurgical. Nous voulons évaluer les résultats cliniques et l'impact économique de cette thérapie par rapport à la gestion médicale des patients en insuffisance cardiaque avec insuffisance mitrale symptomatique. Méthodes: L'étude a été composée de deux phases; une étude d'observation de patients souffrant d'insuffisance cardiaque et de régurgitation mitrale traitée avec une thérapie médicale ou le MitraClip, et un modèle économique. Les résultats de l'étude observationnelle ont été utilisés pour estimer les paramètres du modèle de décision, qui a estimé les coûts et les avantages d'une cohorte hypothétique de patients atteints d'insuffisance cardiaque et insuffisance mitrale sévère traitée avec soit un traitement médical standard ou MitraClip. Résultats: La cohorte de patients traités avec le système MitraClip était appariée par score de propension à une population de patients atteints d'insuffisance cardiaque, et leurs résultats ont été comparés. Avec un suivi moyen de 22 mois, la mortalité était de 21% dans la cohorte MitraClip et de 42% dans la cohorte de gestion médicale (p = 0,007). Le modèle de décision a démontré que MitraClip augmente l'espérance de vie de 1,87 à 3,60 années et des années de vie pondérées par la qualité (QALY) de 1,13 à 2,76 ans. Le coût marginal était 52.500 $ dollars canadiens, correspondant à un rapport coût-efficacité différentiel (RCED) de 32,300.00 $ par QALY gagné. Les résultats étaient sensibles à l'avantage de survie. Conclusion: Dans cette cohorte de patients atteints d'insuffisance cardiaque symptomatique et d insuffisance mitrale significative, la thérapie avec le MitraClip est associée à une survie supérieure et est rentable par rapport au traitement médical.