[Early Structural Valve Deterioration of Third-generation Biological Prosthesis].

The third-generation Trifecta valve, Trifecta GT, has been used in Japan since 2012. The Trifecta GT is characterized by the external leaflet mounting, which increases the effective valve opening area and provide excellent hemodynamics. Lehmann et al. reported a good 8-year avoidance rate of 93.3% for structural valve deterioration( SVD) in 1,241 patients. There are three main causes of SVD after valve replacement using bioprostheses:pannus formation in the left ventricular outflow tract, calcification of the valve leaflets, and noncalcified leaflet tears. Goldman et al. reported 11 SVDs in 710 patients who underwent surgical implantation of Trifecta valve, 10 of which were due to calcification of the valve leaflets and only one of which was due to noncalcified leaflet tears. Herein, we report four cases of early SVD due to noncalcified leaflet tears after valve implantation using the Trifecta GT.

[Giant Anastomotic Aneurysm Associated with Albumin/Glutaraldehyde Sealant as a Late Complication after Acute Aortic Dissection Surgery:Report of a Case].

A 74-year-old woman was taken to our hospital with a chief complaint of chest and back pain. She was diagnosed with Stanford type A acute aortic dissection and underwent ascending aortic replacement. Fifteen months after surgery, a giant anastomotic aneurysm was found at the proximal and distal anastomoses on chest computed tomography (CT), and reoperation was indicated. Following sternal re-entry, anastomotic dehiscence was found where BioGlue, albumin/glutaraldehyde sealant, had been applied during the previous surgery, and caused aneurysm. Severe postoperative adhesion precluded extensive surgery, and redo replacement of the ascending aorta was carried out. Histopathological examination revealed extensive necrosis of smooth muscle cells in the aortic wall at the anastomotic site and a marked inflammatory cell infiltration around the aortic wall and the artificial graft, and association of BioGlue use was suggested. The use of appropriate tissue adhesives to reinforce the dissected aortic wall is important, as well as careful long-term follow-up.

[A Giant Papillary Fibroelastoma in the Right Ventricle].

Papillary fibroelastoma (PFE) accounts for approximately 8% of benign primary cardiac tumors. PFE frequently develops in the left heart system, such as the aortic valve and the mitral valve. We report a case of a giant PFE in the right ventricle. The patient was an 83-year-old woman with a history of chronic atrial fibrillation, diabetes, and hypertension. She had experienced palpitation and shortness of breath for several years. A giant mobile tumor was observed in the right ventricle by transthoracic echocardiography, and its extirpation was performed. Intraoperatively, a giant tumor of 3 cm in diameter was observed on the right ventricular side of the posterior tricuspid leaflet. As the tumor strongly adhered to the tendinous cords, it was unavoidable to resect the tendinous cords. Thus, a tricuspid valve repair was performed in addition to the tumor extirpation. The patient was diagnosed with papillary fibroelastoma by pathological examination.

Preservation of Mobility of the Posterior Mitral Leaflet After Mitral Valve Repair With Neochordae Using Loop Technique.

BACKGROUND: Recently, the loop technique has been standardized for mitral valve repair, with excellent long-term outcomes reported. This study thus analyzed whether the loop technique could preserve mitral leaflet mobility on trans-thoracic echocardiography. METHODS AND RESULTS: Among 367 concomitant patients who underwent mitral valve repair at Keio University Hospital between January 2007 and December 2014, 304 patients had a prolapse of the posterior leaflet. Of these, 84 cases assessed on echocardiography were retrospectively analyzed for this study. These patients were divided into 4 groups based on the procedure used: (1) group L1 (n=28), loop technique alone; (2) group L2 (n=14), loop technique with resection and suture; (3) group L3 (n=33), loop technique with plication of indentation; and (4) group R (n=9), resection and suture alone. The mean postoperative mobile posterior mitral leaflet (PML) angles in groups L1 and L2 (39.3±16.0°, 37.3±16.0°) were significantly larger than those in groups L3 and R (18.8±15.7°, 15.3±15.7°), respectively (P<0.01). Ring size, age, and mobile PML angle had a statistically significant correlation with the postoperative mean mitral valve pressure gradient (P<0.05). CONCLUSIONS: The loop technique preserved PML mobility and enabled implantation of a larger ring, resulting in a reduced mean mitral valve pressure gradient. (Circ J 2016; 80: 663-667).

Oral Nitrate Administration Ameliorates Cardiogenic Shock due to Eclipsed Mitral Regurgitation.

Eclipsed mitral regurgitation (MR) has been reported as transient massive functional MR caused by a sudden coaptation defect in the absence of left ventricular remodeling or epicardial coronary artery stenosis. Coronary spasm or microvascular dysfunction has been suggested to be associated with the pathogenesis. Here, we present a 68-year-old woman with eclipsed MR with cardiogenic shock ameliorated by nitrate. She was admitted for transient shock with massive functional MR. Transient MR was associated with a complete absence of mitral leaflet coaptation owing to tethering of the lateral posterior mitral leaflet. The leaflet tethering was triggered by transient myocardial ischemia around the anterolateral papillary muscle, which could have been caused by coronary spasm and/or microvascular dysfunction. During admission, she experienced similar repeated episodes, which were ameliorated by oral nitrate administration. This is the first described case of eclipsed MR with shock ameliorated by nitrate. Although eclipsed MR, a cause of life-threatening shock, is uncommon, we need to keep in mind that nitrate administration could be a treatment option even in patients with cardiogenic shock.

Periodic Protrusion of Right Coronary Cusp into Left Ventricular Outflow Tract Due to Detachment from the Aortic Annulus Complicated with Infective Endocarditis.

We describe the imaging of unusual dislocation of right coronary cusp into left ventricular outflow tract (LVOT) due to the infective endocarditis. Although the two-dimensional echocardiography identified a protruding mass in LVOT, the three-dimensional echocardiography precisely demonstrated the spatial anatomy of the aortic root, which was confirmed by the surgical operation, implicating the usefulness of three-dimensional echocardiography in this rare anomaly.

[MINIMALLY INVASIVE CARDIAC SURGERY IN JAPAN: INTRODUCTION].

Minimally invasive cardiac surgery (MICS), first introduced in the 1990s, was originally performed via partial sternotomy, the subxyphoid approach, and right anterolateral thoracotomy. Over the past 20 years, MICS procedures have progressed from mere alternatives to standard full sternotomy to endoscope-assisted and then to totally endoscopic open-heart procedures. MICS has gained popularity among surgeons and patients; without sacrificing the safety level and durability of cardiac procedures equivalent to median sternotomy, refinement of MICS technologies has resulted in a decrease in length of hospital stay, less postoperative pain, faster patient recovery, and faster return to activities of normal daily living. Such refinements were achieved not only by the tireless efforts of surgical pioneers but also by the introduction of surgical instruments and endoscopic technologies as well as various, techniques for peripheral cardiopulmonary bypass. On the other hand, an increase in the number of interventions in structural heart diseases such as transcatheter aortic valve implantation, MitraClip percutaneous mitral valve repair therapy, and closure of atrial septal defect is a motivation for further improvement of MICS technologies to enhance safety, durability, and reproducibility.

[MITRAL VALVE REPAIR WITH MINIMALLY INVASIVE CARDIAC SURGERY APPROACH AS ROUTINE PRACTICE].

Although minimally invasive cardiac surgery (MICS) via right minithoracotomy is attracting attention as a minimally invasive approach in cardiac surgery, it has not become a standard, routine approach for mitral valve repair. Although it has spread rapidly in Germany (43%) and USA (20.4%), the proportion of MICS in isolated mitral valve repair still comprises only 15.6% of mitral valve repair surgeries in Japan. For safe, assured introduction of MICS as a routine approach under quality control for good surgical and mid- and long-term results, surgeons experienced in mitral valve repair who perform at least 10 mitral valve repairs per year are necessary. A team approach with surgeons, anesthesiologists, perfusionists, and nurses who are highly motivated is also important.

Safety and efficacy of linezolid in 16 infants and children in Japan.

Linezolid, an oxazolidinone antibiotic, exhibits a broad spectrum of activity against Gram-positive bacteria. It has been licensed for adult use in Japan since 2006 for MRSA infections, and has also been used off-label for pediatric patients. At our university hospital, a total of 16 infants and children (including one non-Japanese Asian) were administered linezolid owing to infection with multidrug-resistant Gram-positive bacteria, after consent had been provided. All patients had severe underlying diseases or indications for surgery. Eighty-eight percent of the causal microorganisms were methicillin-resistant Staphylococcus aureus (MRSA) or methicillin-resistant coagulase-negative Staphylococcus and all were sensitive to linezolid. Linezolid was administered because the antecedent anti-MRSA medications were ineffective or contraindicated, or intravenous-to-oral switch therapy was requested owing to cardiac or orthopedic surgical-site infections. The median duration of administration was 13 days (range 3-31 days). The overall efficacy was 91 % (10/11) in those for whom efficacy could be evaluated. Only two patients (both teen-aged) encountered linezolid-related adverse effects (13 %, 2/16). One patient showed elevation of liver enzymes (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]), requiring that administration be withdrawn, but enzyme levels returned to normal after the patient had been switched to vancomycin. The other patient showed transiently decreased platelet counts. Linezolid is considered generally safe and effective for children in Japan, especially for those who cannot use other anti-MRSA medications or those who require oral antibiotics for infections with multidrug-resistant Gram-positive bacteria.

[Mitral valve repair with artificial chordal creation].

To achieve optimal long-term result of mitral valve repair, artificial chordae creation has got to be an important technique. Artificial chordae creation can preserve leaflet motion of the posterior mitral leaflet and soft coaptation area. Loop technique is suitable technique for creation of multiple artificial chordae, especially in minimally invasive minithoracotomy setting. Loop-in-loop technique is a new technique to realize easy adjusting of the length of the neochordae using slippery Gore-Tex suture. Loop-in-loop technique helps surgeons to afford variety of mitral valve repair techniques and manage complex mitral valve pathologies.

[Efficacy of surgical left ventricular restoration for the patients with ischemic cardiomyopathy; comparison with the surgical treatments for ischemic heart failure (STICH) trial].

The efficacy of surgical left ventricular restoration (LVR) for the patients with ischemic cardiomyopathy was denied by the surgical treatments for ischemic heart failure (STICH) trial. But the conclusion of the STICH trial is wrong and real message of the STICH trial is as follows. LVR is not effective procedure for the patients with poor left ventricular function and small left ventricular dilatation. In the STICH trial, volume reduction rate of the patients with LVR is too little. Based on the low of Laplace, little volume reduction rate do not contribute the improvement of the ventricular function. In our 33 cases of LVR, the survival rates at 5, 7, and 10 years after LVR were 80%, 76% and 76%. On the other hand, the corresponding cardiac event-free rates were 55%. 44%, and 44%. These discrepancies of the value suggest the importance of both the preoperative strategy and the intensive therapy during the postoperative period. We observed some cases that re-enlarged left ventricle after LVR induced heart failure or ventricular arrhythmia. The timing of operation, left ventricular reconstruction of appropriate size and shape considering the function of residual myocardium has significant effect on prognosis. Postoperative ventricular tachycardia (VT) was the major factor influenced the survival rate. After preoperative or intraoperative three-dimensional electrical mapping by CARTO system to detect focus of VT, endocardiectomy combined with cryoablation at the VT focus is performed and postoperative antiarrhythmic medication is added routinely. If LVR will be performed after appreciation of its concept, indication and method, excellent long term prognosis will be expected.

Feasibility of mitral valve repair using the loop technique.

PURPOSE: The most difficult aspect of chordal replacement in a mitral valve repair using expanded polytetrafluoroethylene (ePTFE) sutures, is determining the appropriate length of artificial chorda and ligation of the ePTFE sutures without the knot sliding. PATIENTS AND METHODS: We adopted a loop technique reported by Mohr et al. in 12 consecutive cases from October 2005. Nine cases were comparative broad-range prolapses of the posterior leaflet, 2 cases were anterior and the posterior leaflet and 1 case was vegetation of the anterior leaflet. Chordal replacement was done by 4 loops in 11 cases and by 8 loops in 1 case. RESULTS: Postoperative echocardiography showed more physiological movement of the posterior leaflet than by the resection suture method. When comparing of the peak pressure gradient across the mitral valve on echocardiography between the loop technique group and the non-loop technique group, the gradient in the loop technique group (n=11) was 1.8+/-0.7 mmHg and in the non-loop technique group (n=18) was 3.2+/-1.0 mm Hg. There was a significant statistical difference between 2 groups. The loop technique also seemed to be superior procedure hemodynamically. CONCLUSION: This technique may be useful through both port-access minimally invasive cardiac surgery (MICS) and a conventional approach to the mitral valve, and simplifying chordal replacement. We report on the feasibility of the loop technique based on our experience.

Successful management of severe unilateral re-expansion pulmonary edema after mitral valve repair with mini-thoracotomy using extracorporeal membrane oxygenation.

A 60-year-old man received mitral valve repair via right mini-thoracotomy, which was followed by unilateral re-expansion pulmonary edema on the right side and severe hemoptysis just after the surgery. Despite differential lung ventilation with unilateral high positive end expiratory pressure was initiated for the affected right lung, respiratory function did not improved and hemodynamics was collapsed in the next day. Veno-venous extracorporeal membrane oxygenation was initiated by cannulation of the right jugular and the left femoral vein. After pulmonary function recovered gradually, veno-venous extracorporeal membrane oxygenation was terminated on the fifth postoperative day. He was discharged in ambulatory condition on postoperative day 52.

[Minimally invasive cardiac surgery using port-access method].

From October 1997 to January 2006, we operated on 209 patients with port-access cardiac surgery. The patients were 116 with atrial septal defect (ASD), 85 with mitral valve disease, 2 with coronary artery bypass grafting (CABG), 10 with other (ventricular septal defect, partial endocardial fusion defect, myxoma). The average of postoperative hospital stay is 7 (shortest: 3) days. None of these patient have been readmitted, however, there was 1 mortality. The operative technique for ASD is established in this series. On the other hand, for mitral valve disease, a modification point such as prevention of a complication and shortening of cardiopulmonary bypass time were recognized. It seemed that careful determination of operative indication and establishment of security were important. Improvement and development of operative technology of port-access method will enable future safe total endoscopic or robotic cardiac surgery. In this paper, we report the latest surgical technique of port-access cardiac surgery.

Endoscopic-assisted minimally invasive resection of a papillary muscle blood cyst in an adult patient.

We describe endoscopic-assisted minimally invasive resection of a blood cyst originating from the papillary muscle that caused severe mitral regurgitation and necessitated mitral valve replacement in an active adult woman, as well as a review of the relevant literature. An endoscopic view increases the visibility of the surgical target and facilitates a precise observation of the tumour and dissection at the appropriate layer. The On-X mechanical valve was chosen for mitral valve repair to minimize thromboembolic risk. This patient additionally benefited from endoscopic-assisted right minithoracotomy in terms of both cosmetic and functional aspects.

Mitral Valve Repair via a Minithoracotomy in a Patient With Pectus Excavatum.

Cardiac surgery in patients with pectus excavatum is challenging because of the difficulty associated with achieving optimal surgical exposure and postoperative sternal fixation by using standard instruments. To solve these problems, mitral valve repair was performed via a right minithoracotomy in a 48-year-old man with severe mitral valve regurgitation and pectus excavatum. With the use of conventional median sternotomy, an optimal surgical field was difficult to achieve because of his thoracic deformity. Therefore, surgical fixation via right minithoracotomy using particular equipment was performed. Using right minithoracotomy, we could obtain an optimal surgical field better than that with median sternotomy, and the patient's mitral valve regurgitation was fixed properly. This approach provides mitral valve exposure advantages as well as cosmetic satisfaction.

Alternative peripheral perfusion strategies for safe cardiopulmonary bypass in atrial septal defect closure via a right minithoracotomy approach.

OBJECTIVES: In cases of cardiac surgery via a minimally invasive right minithoracotomy approach, cardiopulmonary bypass is established with peripheral arterial cannulation, frequently with a single femoral artery. Occasionally, alternative perfusion access is required to prevent perfusion site-related complications. In this study, the feasibility of alternative perfusion strategies was verified by comparing the postoperative outcomes and complications. METHODS: The records of 91 consecutive patients (68 women, 23 men; mean age 40.7 ± 16.5 years) who underwent atrial septal defect (ASD) closure via a right minithoracotomy approach between January 2009 and September 2014 were reviewed. Patients were divided into two groups: those with single femoral arterial access (SF group, n = 84), and those with alternative perfusion access (ALT group, n = 7, bilateral femoral arterial cannulation in 6, side-arm graft anastomosed to the femoral artery in 1). RESULTS: Femoral artery diameter was smaller in the ALT group than in the SF group (6.5 ± 0.5 vs. 7.3 ± 1.0 mm, P = 0.013). Operating time was longer in the ALT group than in the SF group (259.2 ± 54.0 vs. 208.3 ± 54.9 min, P = 0.031). One patient was converted to ascending aortic cannulation owing to high perfusion pressure. Postoperative major cardiac or cerebrovascular events, such as death, stroke, or myocardial infarction, did not occur in either group. CONCLUSIONS: Alternative perfusion access was safe in ASD closure via a right minithoracotomy approach. Precise preoperative evaluation of the iliofemoral artery is important for choosing the appropriate perfusion strategy.