Minimally invasive transaortic mitral valve repair during aortic valve replacement

Herein, we report the case of a 77-year-old man who presented with congestive heart failure. Echocardiography and cardiac catheterization revealed severe aortic stenosis with severe mitral regurgitation and a left ventricular ejection fraction of 0.20. Because of comorbidities, the patient was considered to be at high risk for double-valve surgery. In order to reduce the operative risk, a minimally invasive aortic valve replacement was performed together with a transaortic edge-to-edge repair (Alfieri stitch) of the mitral valve. We discuss the surgical technique and note the positive outcome. To our knowledge, this is the 1st report of minimally invasive aortic valve replacement and transaortic mitral valve repair with use of the Alfieri stitch.     

Transcatheter mitral valve replacement

Transcatheter mitral valve (MV) repair, specifically the edge-to-edge leaflet repair, is a less invasive treatment of symptomatic mitral regurgitation (MR) in patients with high or prohibitive surgical risk. In cases with severe leaflet calcification, small mitral orifice area, and/or extremely wide regurgitation across the entire MV commissure, transcatheter MV repair may rather cause suboptimal or potentially hazardous outcomes. In these cases, MV replacement can be a more suitable option. Recently, percutaneous transcatheter MV replacement has emerged as an acceptable therapeutic option for the treatment of degenerated surgical bioprosthetic disease. Moreover, several transcatheter devices for native MV replacement are under evaluation with a hope to provide more complete and reproducible restoration of MV function. In this article, we will review current status, applications, clinical outcomes, and limitations that need to be overcome for transcatheter MV replacement for both degenerated surgical bioprosthetic disease and native MV disorders.     

Mitral valve repair versus mitral valve replacement

Zusammenfassung In den letzten 40 Jahren hat die Mitralklappenchirurgie einen grundlegenden Wandel erfahren. Der initialen Begeisterung nach der Einführung von Klappenprothesen in den 60er Jahren folgte eine Renaissance der Rekonstruktion der Mitralklappe mit der Vorstellung der Ringannuloplastie-Technik in den 70er Jahren. Die Rekonstruktion der Mitralklappe erhält die Integrität der subvalvluären Strukturen, die eine entscheidende Rolle für die linksventrikuläre Funktion spielen. Große Studien, die sowohl Früh- als auch Langzeitergebnisse nach Mitralklappenrekonstruktionen gegenüber prothetischem Klappenersatz betrachteten, zeigten eine geringere Operationsmortalität sowie eine deutlich höhere Langzeitüberlebensrate bei Patienten nach Mitralklappenrekonstruktion. Weiterhin sind spezifische Probleme, wie Thromboembolien oder Endokarditis, die bei Klappenersatzverfahren auftreten können, zu nennen. In Anbetracht dieser Tatsachen sind klappenerhaltende Rekonstruktionstechniken von Vorteil. Jedoch ist die Entscheidung für eine Mitralklappenrekonstruktion von unterschiedlichen Faktoren abhängig, wie der Ätiologie der Mitralklappenerkrankung und der daraus folgenden Pathomorphologie der Klappe, sowie patientenabhängigen Einflüssen, wie z.B. Alter oder Kontraindikationen für eine Antikoagulationstherapie und nicht zuletzt der Erfahrung des Chirurgen. Somit ist der Prozess der Wahl eines geeigneten Operationsverfahrens sehr komplex und individuell von jedem Patienten abhängig zu machen. Sowohl Studiendaten als auch Datenbanken großer Patientenkollektive reflektieren die Vorteile der Mitralklappenrekonstruktion mit einem Rekonstruktionsanteil von bis zu 75 % in der gesamten Mitralklappenchirurgie. In den letzten 5 Jahren wurde der videoassistierte Zugang zur Mitralklappe über eine rechtslaterale Minithorakotomie zu einem etablierten Verfahren entwickelt. Dieser minimalinvasive Zugang erlaubt sowohl komplexe Rekonstruktions- als auch Klappenersatzverfahren unter anderem mit gerüstfreien Bioprothesen. Zusätzliche chirurgische Verfahren, wie die linksatriale Hochfrequenzablation zur Herstellung eines Sinusrhythmus bei Patienten mit Vorhofflimmern, verbessern das Operationsergebnis nach Mitralklappenchirurgie sowohl hinsichtlich der kardialen Funktion als auch der Lebensqualität für den Patienten deutlich und können ebenfalls über den minimalinvasiven Zugang durchgeführt werden. Summary Over the past 40 years mitral valve surgery has changed dramatically. After initial enthusiasm with the introduction of valve prostheses in the 1960s, a renewed interest in repair techniques began in the 1970s with the introduction of annuloplasty rings. These repair techniques revealed that the integrity of the subvalvular apparatus plays an important role in left ventricular function. When considering the major series comparing early and late results of mitral valve repair versus prosthetic mitral valve replacement, operative mortality rate is lower for patients with mitral valve repair. Long-term results also show a superior survival rate after mitral valve reconstruction. In addition, several problems can occur with the prosthetic valve, such as thromboembolism and endocarditis. All of these factors favor valve repair over replacement. The success of mitral valve repair depends on many factors: etiology of the mitral valve disease and the resultant pathomorphology of the valve, patient's circumstances such as age or contraindication for anticoagulation, and the experience of the surgeon. The decision whether to repair or replace the mitral valve depends on these factors. Data in the literature and in large collective databases reflect the advantages of mitral valve repair, with over 75 % of current mitral valve surgeries being repairs. In the past 5 years the exposure of the mitral valve through a right lateral minithoracotomy using video assistance has developed into a widespread technique. This approach allows complex mitral valve repair as well as mitral valve replacement even with biological stentless prostheses, with decreased morbidity. The addition of radiofrequency ablation for restoration of sinus rhythm enhances the outcome after mitral valve surgery, and can also be easily performed through a minithoracotomy technique.     

Chylomediastinum following mitral valve replacement

Chylomediastinum is a rare but potentially serious complication. There is as yet no definitive treatment. We present an exceptional case of chylomediastinum due to mitral valve replacement. The patient was successfully treated using a conservative approach with total parenteral nutrition, nothing by mouth, and mediastinal tube drainage.     

Quadrileaflet stentless mitral valve replacement

BACKGROUND: The study evaluates clinical results and hemodynamic parameters one year after implantation of a stentless quadrileaflet mitral valve (QMV). METHODS: Since August 1997 28 patients received the QMV, patient age was 69 +/- 8 years; 13 had predominant mitral stenosis and 15 incompetence, preoperative NYHA functional class was III or IV and cardiac index 1.8 +/- 0.6 L/min/m2. RESULTS: Surgery was performed using a conventional (25) or a minimally invasive approach (3). 20 patients received a medium and 8 a large-size prosthesis, crossclamp time was 58 +/- 19 min. Additional procedures were myocardial revascularization in four, tricuspid repair in two, and left-atrial radiofrequency ablation to restore sinus rhythm in six patients. Perioperative mortality (1) was not valve-related. All other patients were discharged on time. At postoperative, 6-, and 12-months follow-up mean transvalvular pressure gradients were 4.2 +/- 1.5 / 4 +/- 0.9/ 3.8 +/- 1.4 mmHg and mitral valve orifice area index was 1.5 +/- 0.3 / 1.6 +/- 0.3 / 1.6 +/- 0.4, NYHA class was I or II. CONCLUSIONS: The QMV is well suited for mitral valve replacement. The anulo-ventricular continuity is preserved and the QMV function resembles native mitral valve function. If its performance is maintained in the long term the QMV may be the mitral prosthesis of choice.     

黄芪预处理对心脏瓣膜置换术心肌保护作用的临床研究

目的探讨黄芪在心脏瓣膜置换术中对心肌缺血再灌注损伤的保护作用.方法将30例心脏瓣膜置换术患者随机分为试验组和对照组,两组灌注方法及体外循环方法相同.试验组在转机前于预充液中加入黄芪注射液20 ml.分别于主动脉阻断前、开放多时点采血检测心肌酶CK-MB、cTnI的水平;记录两组患者的体外循环时间、主动脉阻断时间及术中、术后各时点血管活性药物多巴胺的用量及心肌收缩能力(dp/dtmax)恢复情况;观察开放后心脏自动复跳率、室性心律失常发生率等心肌电生理指标;电镜观察手术前、后心肌超微结构变化.结果对照组术后室性心律失常发生率、除颤次数明显高于试验组;试验组缺血再灌注后心肌收缩能力(dp/dtmax)恢复情况优于对照组.开放后6 h、12 h血清心肌酶CK-MB水平对照组和试验组分别为(91.6±20.4)U/L和(52.7±17.3)U/L,(148.7±24.2)U/L和(94.3±16.3)U/L;开放后6 h、12 h血清cTnI水平对照组和试验组分别为(4.973±1.431)ng/ml和(2.622±1.024)ng/ml,(5.054±1.419)ng/ml和(1.908±0.984)ng/ml,对照组明显高于试验组(P＜0.05或P＜0.01).试验组心肌超微结构保存较好,损伤较对照组轻.结论黄芪对心脏瓣膜置换术患者心肌缺血再灌注损伤具有明显保护作用.     

Myocardial infarction caused by compression of anomalous circumflex coronary artery after mitral valve replacement

We report a case of myocardial infarction after mitral valve replacement occurring in a patient with the left cyrcumflex coronary artery arising from the right one. The patient underwent mitral valve replacement with a size 27 Carbomedics prosthesis and a tricuspidal annuloplasty was performed according to the De Vega technique. Patient died on the 20th postoperative day.     

Pregnancy after mechanical mitral valve replacement

BACKGROUND AND AIM OF THE STUDY: Forty-six pregnancies among 32 patients after mitral valve replacement (MVR) were reviewed. Prosthetic valve-related complications, and outcome of pregnancy including feto-maternal mortality and morbidity for different anticoagulation regimens are presented and discussed. METHODS: Among 521 women of fertile age undergoing MVR with a St. Jude Medical mechanical prosthesis, 32 patients developed a total of 46 pregnancies. Average patient follow up was 5 +/- 4 years (range: 10 months-17 years); total follow up was 155 patient years (pt-yr). Follow up commenced at onset of the first pregnancy. RESULTS: Ten-year Kaplan-Meier survival estimate was 94 +/- 6%; 10-year freedom from valve-related events was 33 +/- 14%. Rates for embolism, anticoagulation-related bleeding and mechanical valve thrombosis were 4.5%, 3.2% and 2.6% per pt-yr, respectively. Among 30 patients receiving uninterrupted low-dose oral warfarin plus aspirin throughout pregnancy, three had normal deliveries, two had premature births, one had a low birth weight, seven had spontaneous abortions, and 17 had therapeutic abortions. By contrast, among eight patients who discontinued anticoagulation despite medical advice, seven had normal-term deliveries without thromboembolic complications, and spontaneous abortion occurred in one patient. Of the five women taking low molecular-weight heparin regimen, three had normal deliveries, one had a premature birth, and one an abortion. Two patients taking warfarin replaced by heparin in the first trimester and in the last two weeks, had term deliveries. One of these women developed left atrial thrombus in the third trimester while receiving heparin; after switching back to warfarin, the thrombus dissolved spontaneously. Another patient on heparin throughout the gestation had an uneventful gestation period that resulted in term delivery. There were four cases of prosthetic valve thrombosis during the postpartum period; all of these developed in women who ceased anticoagulation during pregnancy. CONCLUSION: There were no congenital malformations or maternal mortality/morbidity during pregnancy in this series of 20 live births, probably due to the low-dose anticoagulation regimen used. However, anticoagulation cessation was associated with a high prosthetic valve thrombosis rate in the postpartum period, even when a new-generation prosthetic valve of unique design and expected low thrombogenicity was implanted.