[Clinical Considerations in the Surgical Management of Active Infective Endocarditis of the Mitral Valve].

In the surgical management of infective endocarditis (IE), the presence of circulatory failure from valve destruction and vegetation embolization are important factors in determining the timing of surgery. Emergency surgery carries certain risks, such as infection control problems due to the unknown portal of entry of bacteria and infection, and the possibility of worsening cerebral hemorrhage in patients with hemorrhagic cerebrovascular disease. In recent years, there has been a trend toward more aggressive attempts at mitral valve repair for mitral IE, with improved success rates and rates of recurrent mitral regurgitation, and some reports suggesting that valve repair for active IE has better longterm survival rates than valve replacement. One possible factor is that early surgical intervention to resect the lesion may have a significant impact on the cure rate by preventing progression of valve destruction and controlling infection. Based on our clinical experience, we discuss the optimal timing of surgical intervention for mitral valve IE and present the postoperative remote survival rate, avoidance rate of reinfection, and avoidance rate of reoperation.

[Surgical Left Atrial Ablation Through the Left Atrial Appendage During Aortic Valve Replacement].

This is a 2-case report of concomitant left atrial( LA) surgical ablation through the left atrial appendage( LAA) for atrial fibrillation( AF) during aortic valve replacement( AVR). Case 1, a 74-year-old man, and Case 2, an 85-years-old woman, were presented for AVR and AF. Under the cardio-pulmonary bypass, right and left pulmonary vein isolations( PVIs) were performed with radiofrequency( RF) ablation devices. Through the opened LAA, an RF lesion was placed to connect the bilateral PVIs and the LAA, and another RF line was placed toward the mitral annulus. A right atrial( RA) isthmus ablation was also performed through a RA incision. Postoperatively, sinus rhythm and both RA and LA contraction were obtained, and have been maintained for 7.5 and 5 years without classⅠ/Ⅲ antiarrhythmic drugs in Case 1 and 2, respectively. This procedure is considered to be effective and safe, although further study is needed.

[Tricuspid Valve Ring Annuloplasty with Posterior Annular Plication for Functional Tricuspid Regurgitation].

This report presents a modified procedure of tricuspid valve ring annuloplasty (R-TAP) with posterior annular plication for functional tricuspid regurgitation (TR). Sutures on the native annulus were placed by a standard fashion in R-TAP, and those on the posterior annulus and its bilateral commissures were passed through in a narrow range between the 3 and 4 o'clock positions of the 26-mm ring. The other sutures were done with an usual manner and the ring was fixed to the annulus, resulting in the posterior annular plication( bicuspidization). Follow-up was performed for more than 5 years( mean: 7.9 years, range:5.5~11.5 years) by echocardiography in 13 cases. Postoperative TR reduced significantly to less than moderate, which was maintained during the entire follow-up period, even in the case with atrial fibrillation. There was no sign of tricuspid stenosis. R-TAP with posterior annular plication was feasible, reproducible, and effective, although further investigation is needed.

[Preservation of the Spinal Perfusion Artery during Descending Thoracic and Thoracoabdominal Aortic Surgery].

This is a 3-case report of successful descending thoracic and thoracoabdominal aortic surgery by preserving the spinal perfusion artery (SPA) identified preoperatively. In Case 1, an 85-year-old woman, computed tomography (CT) showed Crawford type Ⅴ thoracoabdominal aortic aneurysm (TAAA:60 mm) and a SPA originated from L2. In Case 2, a 76-year-old man, CT revealed type Ⅳ TAAA( 58 mm) and a SPA originated from Th11. In Case 3, a 74-year-old man, CT detected an infectious pseudoaneurysm(44 mm) in the descending thoracic aorta with 2 SPAs originating from Th10 and L2. The ranges of graft replacement were Th7-Th12, Th12-L4, and Th8-Th10, respectively, while preserving all SPAs. All patients recovered well without postoperative neurological deficits. Although the protective effect of the SPA preservation against the spinal cord ischemia is still controversial, preoperative identification of the SPA was useful for planning a surgical strategy for descending thoracic and thoracoabdominal aortic repair surgery.

[Mitral Valve Replacement with the On-X Valve].

This is a 3-case report of mitral valve replacement (MVR) with an On-X mechanical valve followed up to 10 years. Case 1(64-year-old man) and case 2 (66-year-old woman) experienced traffic accident and traumatic event, respectively, in their chronic phase after MVR. Case 1 had multiple bone fractures of the bilateral lower limbs, which was followed by systemic infection and pyogenic spondylitis. He needed long-term antibiotics therapy for more than 4 years. Case 2 fell down at home and severely hit her head, which resulted in a traumatic subarachnoid hemorrhage. She was in a deep coma, and needed discontinuation of anticoagulation therapy for 4 weeks. Case1, 2, and 3(54-year-old man) are doing well in New York Heart Association functional class I without any valve-related thromboembolic or hemorrhagic events at 10, 9 and 8 years after MVR, respectively. On-X valve performance has also been found well maintained in all cases by echocardiography, even after traumatic accident or discontinuation of anticoagulation in Case 1 and 2. In this report, the On-X mechanical valve demonstrated good midterm result of its valve performance in the mitral position and its potential advantages in antithrombogenicity.

[Intraoperative Endoscopic Evaluation of the Aortic Valve in Aortic Valve Repair].

This report discusses intraoperative endoscopic evaluation of the aortic valve performed in 2 cases of aortic valve repair. The "direct" or real image by the endoscopy helped to confirm the preoperatively-known lesion and even to detect a new legion which was not detected preoperatively. The endoscopy also enabled the evaluation of the aortic valve under the pressure-loaded condition without releasing the aortic clamp. Postoperative aortic regurgitation was grade I or less in both cases, although it progressed to grade II at 1 year in case 2. Echocardiographic parameters demonstrated no change in the size of the aortic root configuration for 8 and 5 years in case 1 and case 2, respectively. Intraoperative aortic endoscopy was useful to define the pathogenesis of aortic regurgitation and to evaluate the cusp repair procedures, which may contribute to a good mid-term result of aortic valve repair.

[Bilateral congenital coronary-pulmonary artery fistulas; report of a case].

Bilateral coronary-pulmonary artery fistulas are very rare. We report a case of a 68-year-old woman without any previous medical history, who presented to our hospital after slow onset of chest heaviness on exertion. Coronary computed tomography (CT) and angiography revealed 2 fistulas:one arising from the left anterior descending artery accompanied by an aneurysm and the other from the right coronary artery. We opened the trunk of the pulmonary artery under cardio-pulmonary bypass and cardiac arrest. We recognized the outflow of the shunt just above the right pulmonary cusp, which was closed from the outside. We also closed the aneurysm of the shunt. Neither the fistulas nor the aneurysm was recognized by postoperative CT. The chest symptom disappeared.

[Clinical effects of tolvaptan for patients with stage 4-5 chronic kidney disease in cardiac surgery].

We report clinical effects of tolvaptan, a vasopressin V2 receptor antagonist, in cardiac surgery. Tolvaptan was administrated to 5 patients with non-dialysis dependent stage 4-5 chronic kidney disease (CKD) during an early postoperative stage. Tolvaptan increased urine output and improved respiratory function in all patients without causing hemodynamic deterioration. All patients were able to avoid initiating long-term hemodialysis during hospital stay. Tolvaptan was effective and safe after cardiac surgery for patients with severe CKD.

[Surgical treatment of coronary sinus orifice atresia; report of a case].

We report a case of a 69-year-old man with coronary sinus orifice atresia incidentally found during mitral and tricuspid valve operation in. Preoperatively, a patent left superior vena cava was noted. An abnormal opening of the coronary sinus was recognized in the inter-atrial septum of the left atrium near the postero-medial commissure of the mitral valve. The coronary sinus was absent in the right atrium. A coronary sinus was created by resecting the inter-atrial septum of the right atrium, and the abnormal opening of the coronary sinus at the left atrium was closed with an autologus pericardial patch. Tricuspid annuloplasty was performed with a 30 mm MC3 ring. Postoperative coronary sinus flow was confirmed normal by enhanced computed tomography (CT). Preoperative recognition of this rare disease is important, especially when the surgical candidate has a patent left superior vena cava.

Single patch technique for aortic annulus reconstruction in prosthetic valve endocarditis.

Aortic root reconstruction during aortic root replacement for a patient with prosthetic valve endocarditis and aortic root abscess can be a difficult procedure with many possible complications. In this video case report, we describe our novel technique using a single bovine pericardial patch that avoids deep stitches or external sutures to support the friable annulus. Compared with more standard methods, this approach has shorter cross-clamp and cardiopulmonary bypass times and is less demanding technically.

Correction: Fabrication of scaffold-free tubular cardiac constructs using a Bio-3D printer.

[This corrects the article DOI: 10.1371/journal.pone.0209162.].

Adult-onset primary Ewing's sarcoma of the right atrium: a case report.

BACKGROUND: Primary cardiac tumors, which are only detected in 0.001-0.03% of autopsies, are rare. Only 25% of primary cardiac tumors are malignant, of which 95% are sarcomas. Ewing's sarcoma, one of the Ewing's sarcoma of family tumors, is thought to be derived from neural crest cells. While Ewing's sarcoma usually presents in the bone of children, Ewing's sarcoma of cardiac origin is rare, with only a few reports described in the literature. The prognosis is unpredictable because of the scarcity and unestablished treatment. We herein report an extremely rare case of primary cardiac Ewing's sarcoma in the right atrium of a 64-year-old man. CASE PRESENTATION: The patient is a 64-year-old Japanese male who was referred to our hospital to treat a floating mass of the right atrium (RA). Although the patient was asymptomatic, we performed an operation to urgently resect the floating mass on the next day of admission due to the risk of pulmonary embolism. The operation was performed under cardiopulmonary bypass and cardiac arrest. We resected the tumor with at least 1.5 cm of the RA wall as a margin. The postoperative pathological diagnosis of the mass was compatible with a primitive neuroectodermal tumor (PNET, a form of Ewing's sarcoma). The cells were positive for CD56, CD99, and Vimentin and negative for S-100 and Desmin. Although no malignant cells were observed in the margin of the resected RA wall and the sarcoma was completely resected, he was transferred to another hospital to receive adjuvant postoperative chemotherapy to improve the prognosis by preventing subclinical micrometastasis. CONCLUSIONS: We experienced an extremely rare case of primary cardiac Ewing's sarcoma in the right atrium of a 64-year-old man, which was successfully resected under cardiac arrest. Although the sarcoma was completely resected, postoperative chemotherapy and long-term follow-up are recommended for patients with primary cardiac sarcoma because of the high rates of metastasis and recurrence.

Aortic valve replacement and tricuspid valve annuloplasty via a left thoracotomy in an adult with left pulmonary agenesis.

We report a case of a 66-year-old man who was diagnosed with severe aortic regurgitation, moderate tricuspid regurgitation and chronic atrial fibrillation. Preoperative computed tomography showed left lung agenesis. We performed aortic valve replacement, tricuspid valve annuloplasty and right pulmonary vein isolation via a left thoracotomy. This approach provided an adequate field of view.

Publisher Correction: Development of an immunodeficient pig model allowing long-term accommodation of artificial human vascular tubes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Development of an immunodeficient pig model allowing long-term accommodation of artificial human vascular tubes.

Before they are used in the clinical setting, the effectiveness of artificially produced human-derived tissue-engineered medical products should be verified in an immunodeficient animal model, such as severe combined immunodeficient mice. However, small animal models are not sufficient to evaluate large-sized products for human use. Thus, an immunodeficient large animal model is necessary in order to properly evaluate the clinical efficacy of human-derived tissue-engineered products, such as artificial grafts. Here we report the development of an immunodeficient pig model, the operational immunodeficient pig (OIDP), by surgically removing the thymus and spleen, and creating a controlled immunosuppressive protocol using a combination of drugs commonly used in the clinical setting. We find that this model allows the long-term accommodation of artificial human vascular grafts. The development of the OIDP is an essential step towards a comprehensive and clinically relevant evaluation of human cell regeneration strategies at the preclinical stage.

Fabrication of scaffold-free tubular cardiac constructs using a Bio-3D printer.

A major challenge in cardiac tissue engineering is the host's immune response to artificial materials. To overcome this problem, we established a scaffold-free system for assembling cell constructs using an automated Bio-3D printer. This printer has previously been used to fabricate other three-dimensional (3D) constructs, including liver, blood vessels, and cartilage. In the present study, we tested the function in vivo of scaffold-free cardiac tubular construct fabricated using this system. Cardiomyocytes derived from induced pluripotent stem cells (iCells), endothelial cells, and fibroblasts were combined to make the spheroids. Subsequently, tubular cardiac constructs were fabricated by Bio-3D printer placing the spheroids on a needle array. Notably, the spheroid fusion and beat rate in the constructs were observed while still on the needle array. After removal from the needle array, electrical stimulation was used to test responsiveness of the constructs. An increased beat rate was observed during stimulation. Importantly, the constructs returned to their initial beat rate after stimulation was stopped. In addition, histological analysis shows cellular reorganization occurring in the cardiac constructs, which may mimic that observed during organ transplantation. Taken together, our results indicate that these engineered cardiac tubular constructs, which address both the limited supply of donor tissues as well as the immune-induced transplant rejection, has potential to be used for both clinical and drug testing applications. To our knowledge, this is the first time that cardiac tubular constructs have been produced using optimized Bio-3D printing technique and subsequently tested for their use as cardiac pumps.

The addition of human iPS cell-derived neural progenitors changes the contraction of human iPS cell-derived cardiac spheroids.

BACKGROUND: We havebeen attempting to use cardiac spheroids to construct three-dimensional contractilestructures for failed hearts. Recent studies have reported that neuralprogenitors (NPs) play significant roles in heart regeneration. However, theeffect of NPs on the cardiac spheroid has not yet been elucidated. OBJECTIVE: This studyaims to demonstrate the influence of NPs on the function of cardiac spheroids. METHODS: Thespheroids were constructed on a low-attachment-well plate by mixing humaninduced pluripotent stem (hiPS) cell-derived cardiomyocytes and hiPScell-derived NPs (hiPS-NPs). The ratio of hiPS-NPs was set at 0%, 10%, 20%,30%, and 40% of the total cell number of spheroids, which was 2500. The motionwas recorded, and the fractional shortening and the contraction velocity weremeasured. RESULTS: Spheroidswere formed within 48 h after mixing the cells, except for the spheroidscontaining 0% hiPS-NPs. Observation at day 7 revealed significant differencesin the fractional shortening (analysis of variance; p = 0.01). The bestfractional shortening was observed with the spheroids containing 30% hiPS-NPs.Neuronal cells were detected morphologically within the spheroids under aconfocal microscope. CONCLUSION: Theaddition of hiPS-NPs influenced the contractile function of the cardiacspheroids. Further studies are warranted to elucidate the underlying mechanism.

Should the annulus be fixed in aortic valve-sparing root replacement with remodeling?

OBJECTIVES: If the aortic root dilates after native aortic valve-sparing root reconstruction with remodeling, aortic regurgitation may recur. However, it has not been demonstrated clearly that the aortic root dilates after remodeling. METHODS: This study enrolled 15 patients who underwent an aortic valve-sparing operation with remodeling (2002-2014) but without any ventriculo-aortic junction (VAJ) fixation. Technically, special care was taken to pass the sutures through the fibrous annulus. The diameter of the aortic root (VAJ, neosinus of Valsalva, and sinotubular junction), degree of aortic regurgitation, and effective height of the aortic valve were measured in the patients. All patients had postoperative follow-up, and the median follow-up period was 7.3 (IQR: 3.1-8.3) years. RESULTS: The mean preoperative diameters of the VAJ, sinus of Valsalva, and sinotubular junction were 23.5 ± 2.3 (20-27) mm, 51.1 ± 7.2 (43-60) mm, and 42.4 ± 9.4 (29-58) mm, respectively. The postoperative diameters of the VAJ changed from 21.6 ± 2.6 (early) to 21.8 ± 2.9 mm (late) (p = 0.75). The diameters of the sinus of Valsalva and sinotubular junction changed from 26.5 ± 3.0 (early) to 28.5 ± 4.2 mm (late) (p = 0.0013), and 22.4 ± 3.0 (early) to 24.3 ± 3.3 mm (late) (p = 0.0003), respectively. The effective height of the aortic valve changed from 9.7 ± 1.3 (early) to 8.9 ± 2.0 mm (late) (p = 0.08). The degree of aortic regurgitation (grade: 0-4) changed from 0.3 ± 0.5 (early) to 1.2 ± 0.8 (late) (p = 01558). CONCLUSIONS: Significant VAJ dilation and changes in aortic valve configuration after our remodeling procedure were not observed. Therefore, fixation of the annulus with remodeling may not be needed for cases without preoperative dilation of the annulus.

Surgical treatment of valvular and supravalvular aortic stenosis in homozygous familial hypercholesterolemia.

A 61-year-old male with homozygous familial hypercholesterolemia presented with dyspnea and syncope. He had been treated with low-density lipoprotein apheresis for 26 years. Echocardiography and computed tomography showed severe valvular and supravalvular aortic stenosis. Computed tomography and cardiac catheterization revealed a severely calcified narrowed aortic root and an occlusion in the proximal right coronary artery. During surgery, the ascending aorta was replaced under deep hypothermic circulatory arrest without aortic cross-clamping. After that, the aortic root from the annulus to the sino-tubular junction was enlarged with a two-ply bovine pericardial patch. An aortic valve replacement with a 17 mm mechanical valve and coronary artery bypass grafting to the right coronary artery were performed. The patient recovered from the surgery without any cerebrovascular complications.

Real-time three-dimensional transesophageal echocardiography is useful for the localization of a small mitral paravalvular leak.

The use of multiplane transesophageal echocardiography (TEE) to reconstruct 3-dimensional (3D) images is limited by time-consuming, multiplane image acquisition and the need for offline processing. To overcome these limitations, a 3D fully sampled matrix array transducer was recently developed to allow real-time acquisition and online display of 3D images. In this case, real-time 3D transesophageal echocardiography produced clear image of a small paraprosthetic leak point. Although the surgical view from the left atrium was poor due to severe adhesions, we were able to perform optimal repair of the small leak after intraoperative confirmation of the location of the leak that was identified by preoperative real-time 3D transesophageal echocardiography.